CTLPF - Cytotoxic T-Lymphocyte Precursor Frequency. Looking for abbreviations of CTLPF? It is Cytotoxic T-Lymphocyte Precursor Frequency. Cytotoxic T-Lymphocyte Precursor Frequency listed as CTLPF
TY - JOUR. T1 - Peripheral burst of tumor-specific cytotoxic T lymphocytes and infiltration of metastatic lesions by memory CD8+ T cells in melanoma patients receiving interleukin 12. AU - Mortarini, Roberta. AU - Borri, Alessandra. AU - Tragni, Gabrina. AU - Bersani, Ilaria. AU - Vegetti, Claudia. AU - Bajetta, Emilio. AU - Pilotti, Silvana. AU - Cerundolo, Vincenzo. AU - Anichini, Andrea. PY - 2000/7/1. Y1 - 2000/7/1. N2 - Systemic effects on T-cell-mediated antitumor immunity, on expression of T-cell adhesion/homing receptors, and on the promotion of T-cell infiltration of neoplastic tissue may represent key steps for the efficacy of immunological therapies of cancer. In this study, we investigated whether these processes can be promoted by s.c. administration of low-dose (0.5 μg/kg) recombinant human interleukin-12 (rHuIL-12) to metastatic melanoma patients. A striking burst of HLA-restricted CTL precursors (CTLp) directed to autologous tumor was documented in peripheral blood by a ...
Class I MHC-restricted cytotoxic T lymphocyte recognition of cells infected with human cytomegalovirus does not require endogenous viral gene expression. ...
TY - JOUR. T1 - Human immunodeficiency virus type 1-specific cytotoxic T lymphocyte activity is inversely correlated with HIV type 1 viral load in HIV type 1- infected long-term survivors. AU - Betts, Michael R.. AU - Krowka, John F.. AU - Kepler, Thomas B.. AU - Davidian, Marie. AU - Christopherson, Cindy. AU - Kwok, Shirley. AU - Louie, Leslie. AU - Eron, Joseph. AU - Sheppard, Haynes. AU - Frelinger, Jeffrey A.. PY - 1999/9/1. Y1 - 1999/9/1. N2 - HIV-1-specific cytotoxic T cell (CTL) activity has been suggested to correlate with protection from progression to AIDS. We have examined the relationship between HIV-specific CTL activity and maintenance of peripheral blood CD4+ T lymphocyte counts and control of viral load in 17 long-term survivors (LTSs) of HIV-1 infection. Longitudinal analysis indicated that the LTS cohort demonstrated a decreased rate of CD4+ T cell loss (18 cells/mm3/year) compared with typical normal progressors (approximately 60 cells/mm3/year). The majority of the LTSs had ...
Little is known of the changes in human immunodeficiency virus type 1 (HIV-1)-specific effector cytotoxic T lymphocytes (CTL) after potent antiretroviral therapy. Using HLA/peptide tetrameric complexes, we show that after starting treatment, there are early rapid fluctuations in the HIV-1-specific CTL response which last 1 to 2 weeks. These fluctuations are followed by an exponential decay (median half-life, 45 days) of HIV-1-specific CTL which continues while viremia remains undetectable. These data have implications for the immunological control of drug-resistant virus.
Little is known of the changes in human immunodeficiency virus type 1 (HIV-1)-specific effector cytotoxic T lymphocytes (CTL) after potent antiretroviral therapy. Using HLA/peptide tetrameric complexes, we show that after starting treatment, there are early rapid fluctuations in the HIV-1-specific CTL response which last 1 to 2 weeks. These fluctuations are followed by an exponential decay (median half-life, 45 days) of HIV-1-specific CTL which continues while viremia remains undetectable. These data have implications for the immunological control of drug-resistant virus.
TY - JOUR. T1 - Effector cytotoxic T lymphocyte numbers induced by vaccination should exceed levels in chronic infection for protection from HIV. AU - Altes, H K. AU - Price, D A. AU - Jansen, Vincent A. A.. PY - 2001/10/12. Y1 - 2001/10/12. KW - AIDS Vaccines. KW - CD4-Positive T-Lymphocytes. KW - HIV Infections. KW - Humans. KW - Lymphocyte Count. KW - Models, Immunological. KW - T-Lymphocytes, Cytotoxic. KW - Vaccination. KW - Viremia. M3 - Article. C2 - 11567737. VL - 20. SP - 3. EP - 6. JO - Vaccine. JF - Vaccine. SN - 0264-410X. IS - 1-2. ER - ...
Virus-specific cytotoxic T-lymphocyte (CTL) responses are critical in the control of human immunodeficiency virus type 1 (HIV-1) infection and will play an important part in therapeutic and prophylactic HIV-1 vaccines. The identification of virus-specific epitopes that are efficiently recognized by CTL is the first step in the development of future vaccines. Here we describe the immunological characterization of a number of novel HIV-1-specific, HLA-A2-restricted CTL epitopes that share a high degree of conservation within HIV-1 and a strong binding to different alleles of the HLA-A2 superfamily. These novel epitopes include the first reported CTL epitope in the Vpr protein. Two of the novel epitopes were immunodominant among the HLA-A2-restricted CTL responses of individuals with acute and chronic HIV-1 infection. The novel CTL epitopes identified here should be included in future vaccines designed to induce HIV-1-specific CTL responses restricted by the HLA-A2 superfamily and will be important to
Virus-specific cytotoxic T-lymphocyte (CTL) responses are critical in the control of human immunodeficiency virus type 1 (HIV-1) infection and will play an important part in therapeutic and prophylactic HIV-1 vaccines. The identification of virus-specific epitopes that are efficiently recognized by CTL is the first step in the development of future vaccines. Here we describe the immunological characterization of a number of novel HIV-1-specific, HLA-A2-restricted CTL epitopes that share a high degree of conservation within HIV-1 and a strong binding to different alleles of the HLA-A2 superfamily. These novel epitopes include the first reported CTL epitope in the Vpr protein. Two of the novel epitopes were immunodominant among the HLA-A2-restricted CTL responses of individuals with acute and chronic HIV-1 infection. The novel CTL epitopes identified here should be included in future vaccines designed to induce HIV-1-specific CTL responses restricted by the HLA-A2 superfamily and will be important to
Keratinocytes expressing the human papillomavirus (HPV) type 16 E7 protein, as a transgene driven by the K14 promoter, form a murine model of HPV-mediated epithelial cancers in humans. Our previous studies have shown that K14E7 transgenic skin grafts onto syngeneic mice are not susceptible to immune destruction despite the demonstrated presence of a strong, systemic CTL response directed against the E7 protein. Consistent with this finding, we now show that cultured, E7 transgenic keratinocytes (KC) express comparable endogenous levels of E7 protein to a range of CTL-sensitive E7-expressing cell lines but are not susceptible to CTL-mediated lysis in vitro. E7 transgenic and non-transgenic KC are susceptible to conventional mechanisms of CTL-mediated lysis, including perforin and Fas/FasL interaction when an excess of exogenous peptide is provided. The concentration of exogenous peptide required to render a cell susceptible to lysis was similar between KC and other conventional CTL targets (e.g. ...
TY - JOUR. T1 - Rapid and long-term changes to host cytotoxic T lymphocyte precursors reactive to donor antigens caused by intravenous injection of histoincompatible lymphocytes. AU - Martin, Diego R.. AU - Sheng-Tanner, Xiaofang. AU - Miller, Richard G.. PY - 1992/7. Y1 - 1992/7. N2 - It has been shown previously that a single intravenous injection of mouse F, LNC into either parent results in a rapid reduction in the ability of the recipient to generate CTL reactive against donor antigens in an in vitro MLR. The underlying mechanism appears to be the in-activation of host CTL precursors that can recognize donor lymphocytes that have entered the recirculating pool. The donor lymphocytes may be acting as functionally deleting APC, or veto cells. Here, we have injected C57BL/6 (B6) mice with (C57BL/6XDBA/2) F, (FO LNC. The CTL response against donor LNC was maximally reduced by 2 days and stayed reduced for at least 6 weeks, but ultimately recovered to normal levels. The response reduction ...
OBJECTIVE: HIV-specific cytotoxic T lymphocytes (CTL) are believed to play an important role in containing viral replication throughout HIV-1 infection. Previous studies have attempted to quantify the HIV-1-specific CTL precursor frequency during primary HIV infection by using limiting dilution analysis, which almost certainly underestimates the true CTL frequency. Here we use a relatively new technique to quantify HIV-specific CD8 T cells in primary HIV infection. METHODS: We have used soluble tetrameric complexes of HLA class I molecules complexed with HIV epitope peptides to study the dynamics and frequency of HIV-specific CD8 T cells in relation to plasma viral load in early HIV infection, in three patients with a highly focused HIV-specific CTL response. RESULTS: We show that the frequencies of HIV-1-specific CD8 T cells in acute infection are significantly higher than previously documented and can be demonstrated well before full seroconversion. These studies also confirm the immunodominance of
Vaccinia virus (VV) inhibits the presentation of certain epitopes from influenza virus nucleoprotein (NP), haemagglutinin (HA) and non-structural 1 (NS1) proteins to CD8+ cytotoxic T lymphocytes (CTL) by an unknown mechanism. We have investigated whether VV genes B13R and B22R, which encode proteins with amino acid similarity to serine protease inhibitors (serpins), are involved in this process. Recombinant VVs were constructed which express influenza virus proteins HA, NP or NS1 and which lack serpin gene B13R or both B13R and B22R. The lysis of cells infected with these viruses by influenza virus-specific CD8+ CTL was compared to the lysis of cells infected with viruses expressing both the influenza proteins and the serpin genes. Cytotoxicity assays showed that deletion of the VV serpin genes B13R and B22R and other genes between B13R and B24R did not increase the level of lysis, indicating that these genes are not involved in inhibition of antigen presentation of the epitopes tested.
TIL from metastatic melanoma proliferated by greater than 1,000-fold (840-3,675, mean 1,543) after 6 wk in culture of mixtures of TIL and tumor cells with rIL-2 alone. Cytolysis was restricted to autologous tumor cells. CD8+ T cells were the predominant population of TIL before and after expansion, and were primarily responsible for autologous tumor-specific CTL activity. No other rIL-2-activated lymphocytes from peripheral blood, lymph nodes with melanoma metastasis, or TIL from sarcoma or renal cell carcinoma had autologous tumor-specific CTL activity. There were few or no CD16+ NK cells in TIL from metastatic melanoma before or after incubation with rIL-2, respectively. However, TIL from sarcoma or renal cell carcinoma contained a substantial proportion of CD3-CD16+ NK cells, which increased in number in culture with rIL-2. Purified CD16+ NK cells as well as CD3+CD16- T cells from rIL-2-activated TIL of renal cell carcinoma displayed MHC-nonrestricted cytotoxicity. At the clonal level as ...
The propensity of HIV-1 for genetic variation, a consequence of error-prone reverse transcription combined with high rates of replication, is thought to contribute to the establishment of persistent infection in the host despite the presence of a vigorous antiviral immune response. Protective immunity to viruses is mediated primarily by cytotoxic T lymphocytes, which recognize viral peptides of 8-11 amino acids bound to major histocompatibility complex class I molecules on the surface of infected cells. In this review we examine the mechanisms by which mutation within peptide antigen-encoding regions of the viral genome enables HIV-1 to evade recognition by virus-specific cytotoxic T lymphocytes. The discussion is relevant to other genetically unstable viruses and more generally to intracellular pathogens of variable antigenicity.
|jats:p|The highly sensitive quantitation of virus-specific CD8+ T cells using major histocompatibility complex-peptide tetramer assays has revealed higher levels of cytotoxic T lymphocytes (CTLs) in acute and chronic virus infections than were recognized previously. However, studies in lymphocytic choriomeningitis virus infection have shown that tetramer assays may include measurement of a substantial number of tetramer-binding cells that are functionally inert. Such phenotypically silent CTLs, which lack cytolytic function and do not produce interferon (IFN)-γ, have been hypothesized to explain the persistence of virus in the face of a quantitatively large immune response, particularly when CD4 help is impaired. In this study, we examined the role of functionally inert CTLs in chronic HIV infection. Subjects studied included children and adults (n = 42) whose viral loads ranged from <50 to >100,000 RNA copies/ml plasma. Tetramer assays were compared with three functional assays: enzyme
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The precise role played by HIV-specific cytotoxic T lymphocytes (CTL) in HIV infection remains controversial. Despite strong CTL responses being generated during the asymptomatic phase, the virus persists and AIDS ultimately develops. It has been argued that the virus is so variable, and the virus turnover so great that escape from CTL recognition would occur continually, but so far there is limited evidence for CTL escape. The opposing argument is that evidence for CTL escape is present but hard to find because multiple anti-HIV immune responses are acting simultaneously during the asymptomatic phase of infection. We describe six donors who make a strong CTL response to an immunodominant HLA-B27-restricted epitope. In the two donors who progressed to AIDS, CTL escape to fixation by the same mutation was observed, but only after 9-12 years of epitope stability. CTL escape may play an important role in the pathogenesis of HIV infection.
This study demonstrates that use of structural information improves the definition and optimization of cytotoxic T lymphocyte (CTL) epitopes. Epitope optimization usually requires numerous truncated peptides or a reverse immunogenetic approach, where the peptide binding motif is used to predict epitopes. These binding motifs do not reliably predict all peptides which are CTL epitopes. Comparison of 24 peptides eluted from HLA-B8 with 10 HLA-B8-restricted defined CTL epitopes demonstrated that known epitopes varied considerably at anchor positions. We used structural information based on determination of the crystal structure of the HLA-B8-GGKKKYKL complex to reassess previously described CTL epitopes, to predict new epitopes, and to predict the consequences of naturally occurring variation within epitopes. These predictions were confirmed by cytotoxicity and binding assays. Use of combined structural and immunological data more accurately defines the true peptide-binding motif of a restriction element
Major histocompatibility (MHC)-restricted, human immunodeficiency virus type one (HIV-1)-specific, cytotoxic T lymphocytes (CTLs) were detected in the peripheral blood mononuclear cells (PBMCs) of HIV-1-infected individuals. Using a system of autologous B and T lymphoblastoid cell lines infected with recombinant vaccinia vectors (VVs) expressing HIV-1 gene products, we were able to detect HIV-1-specific cytolytic responses in the PBMCs of 88% of HIV-1-seropositive hemophiliac patients in the absence of in vitro stimulation. These cytolytic responses were directed against both HIV-1 envelope and gag gene products. The responses were resistant to natural killer (NK) cell depletion and were inhibited by monoclonal antibodies (MoAbs) to the T cell receptor, CD8 surface antigens, and MHC class I antigens, suggesting a classical MHC class I restricted, virus-specific CTL response.
Swine leukocyte antigen (SLA) class I molecules play a crucial role in generating specific cellular immune responses against viruses and other intracellular pathogens. They mainly bind and present antigens of intracellular origin to circulating MHC I-restricted cytotoxic T lymphocytes (CTLs). Binding of an appropriate epitope to an SLA class I molecule is the single most selective event in antigen presentation and the first step in the killing of infected cells by CD8+ CTLs. Moreover, the antigen epitopes are strictly restricted to specific SLA molecules. In this study, we constructed SLA class I complexes in vitro comprising viral epitope peptides, the extracellular region of the SLA-1 molecules, and β2-microglobulin (β2m) using splicing overlap extension polymerase chain reaction (SOE-PCR). The protein complexes were induced and expressed in an Escherichia coli prokaryotic expression system and subsequently purified and refolded. Specific binding of seven SLA-1 proteins to one classical swine fever
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[134 Pages Report] Check for Discount on Cytotoxic T Lymphocyte Protein 4 (Cytotoxic T Lymphocyte Associated Antigen 4 or CD152 or CTLA4) - Pipeline Review, H2 2017 report by Global Markets Direct. Cytotoxic T Lymphocyte Protein 4 (Cytotoxic T Lymphocyte Associated Antigen...
The evolution of the HIV-specific CD8+ T cell response in patients receiving potent combination therapy has been well documented in adult patients. However, no study reported whether baseline HIV-specific CD8+ T cell response is linked to treatment outcome. The aims of this study were to investigate both the impact of baseline memory cytotoxic T lymphocytes (CTL) on treatment outcome and the effect of potent therapy on memory HIV-specific CTL in HIV-1-infected pediatric patients. The study group comprised 30 children who started a first-line combination treatment including at least three drugs from two different classes and were longitudinally followed during treatment. Their memory HIV-specific responses were measured at baseline and during treatment, as well as their plasma viremia and CD4+ levels. The intensity of memory Gag-specific CTL and the breadth of the CTL response at the beginning of treatment were significantly correlated with lower plasma viral load during treatment, independently of
The composition of tumor-targeted T cell infiltrates is a major prognostic factor in colorectal cancer (CRC) outcome; however, the functional role of these populations in prolonging patient survival remains unclear. Here, we evaluated 190 patients with CRC for the presence of functionally active tumor-infiltrating lymphocytes (TILs), the tumor specificity of these TILs, and the correlation between patient TILs and long-term survival. Using intracytoplasmic cytokine staining in conjunction with HLA multimers loaded with tumor peptide and antigen-specific cytokine secretion assays, we determined that TNF-α expression delineates a population of tumor antigen-specific (TA-specific) cytotoxic T lymphocytes (CTLs) present within tumors from patients with CRC. Upregulation of TNF-α expression in TILs strongly correlated with an increase in the total amount of intratumoral TNF-α, which is indicative of tumor-specific CTL activity. Moreover, a retrospective multivariate analysis of 102 patients with ...
The composition of tumor-targeted T cell infiltrates is a major prognostic factor in colorectal cancer (CRC) outcome; however, the functional role of these populations in prolonging patient survival remains unclear. Here, we evaluated 190 patients with CRC for the presence of functionally active tumor-infiltrating lymphocytes (TILs), the tumor specificity of these TILs, and the correlation between patient TILs and long-term survival. Using intracytoplasmic cytokine staining in conjunction with HLA multimers loaded with tumor peptide and antigen-specific cytokine secretion assays, we determined that TNF-α expression delineates a population of tumor antigen-specific (TA-specific) cytotoxic T lymphocytes (CTLs) present within tumors from patients with CRC. Upregulation of TNF-α expression in TILs strongly correlated with an increase in the total amount of intratumoral TNF-α, which is indicative of tumor-specific CTL activity. Moreover, a retrospective multivariate analysis of 102 patients with ...
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|jats:p|For viruses to establish persistent infections in their hosts, they must possess some mechanism for evading clearance by the immune system. When inoculated into adult immunocompetent mice, wild-type lymphocytic choriomeningitis virus (LCMV ARM) induces a CD8(+)-mediated cytotoxic T lymphocyte (CTL) response that clears the infection within 7-14 d (CTL+ [P-]). By contrast, variant viruses isolated from lymphoid tissues of persistently infected mice fail to induce a CTL response and are thus able to establish a persistent infection in adult mice (CTL- [P+]). This report compares the interaction of CTL+ (P-) and CTL- (P+) viruses with cells of the immune system. Both types of virus initially bind to 2-4% of CD4+ and CD8+ T lymphocytes and replicate within cells of both subsets. The replication of CTL- (P+) and CTL+ (P-) viruses in lymphocytes in vivo is similar for the first 5 d after initiating infection. Thereafter, in mice infected with CTL- (P+) variants, lymphocytes retain viral genetic
Cytotoxic T lymphocytes (CTLs) are generated by immune activation of cytotoxic T cells (Tc cells). They are generally CD8+, which makes them MHC class I restricted. CTLs are able to eliminate most cells in the body since most nucleated cells express class I MHC molecules. The CTL-mediated immune system can be divided into two phases. In the first phase, functional effector CTLs are generated from naive Tc cells through activation and differentiation. In the second phase, affector CTLs destroy target cells by recognizing the antigen-MHC class I complex. In phase one, effector CTLs are generated from CTL precursors. The CTL precursors include naive Tc cells since they are incapable of killing target cells. After a precursor cell has been activated, it can then differentiate into a functional CTL with cytotoxic activity. There are three sequential signals that are required to complete this process. First, there is TCR recognition of the peptide-MHC class I complex. This step allows the cell to ...
Significant data support the hypothesis that HIV-specific cytotoxic T lymphocyte (CTL) responses contribute to the control and potential clearance of the virus. Vaccines designed specifically to induce CTL responses are likely to be well suited for treatment of HIV infection. The conceptual basis of the EP HIV-1090 vaccine is the use of highly defined CTL epitopes as the vaccine immunogen. The vaccine is formulated with a water-soluble polymer that stabilizes and protects the DNA and facilitates uptake by cells. Preclinical studies have shown that the vaccine induces strong CTL responses in animal models. This study will evaluate the safety and tolerability of the vaccine and the immune response to the vaccine in HIV-1-infected individuals who are being treated with highly active antiretroviral therapy (HAART) and have a CD4 count of 350 cells/mm3 or more and fully suppressed viral replication on stable HAART.. Each patient will receive a total of four immunizations to be given at Day 0 and at ...
Because tumor-specific cytotoxic T lymphocytes (CTL) recognize tumor antigen associated with MHC class I molecules expressed on the tumor surface, any alteration in the tumor antigen processing and presentation will greatly affect CTL immunity. In fact, downregulation or complete loss of MHC I molecules have been demonstrated in a wide array of tumors, particularly prostate, colon, lung, and breast cancers (5-12). Disruption or downregulation of antigen processing components, such as TAP (transporters associated with antigen processing) and LMP (components of the proteasome complex) genes have also been observed in several tumor types, including breast, prostate, and renal cancers (13-15). Another tactic tumors exploit is downregulation or alteration of tumor antigens. Several independent research groups described the loss of melanoma-associated antigen either during treatment by adoptive transfer of ex vivo expanded antigen-specific CTL (16) or during immune therapy by tumor vaccinations ...
The role of HIV-specific cytotoxic T-lymphocytes (CTL) in controlling viremia and protecting against disease progression following vertical infection may be dependent upon CTL functional responses as well as on the timing of detection, magnitude, and breadth of the responses. Novel and sensitive assay systems (MHC-peptide tetramers, ELISPOT assays, intracellular cytokine assays) have enhanced the detection and characterization of virus-specific CTL responses in the peripheral blood. This study will use these novel methods to examine the timing of detection, magnitude, specificity, and in vitro functional properties of HIV-specific CTL in infants; to evaluate the effects of potent combination antiretroviral therapy on HIV-specific CTL in infants; and to evaluate the immunogenicity of recombinant pox-based vaccines in HIV infected infants with prolonged viral suppression following early potent combination antiretroviral therapy.. Blood samples from infants born to HIV infected women will be ...
The interaction of T helper (Th) cells with syngeneic and allogeneic cytotoxic T lymphocyte precursors (CTL.P) has been investigated. Unprimed and mixed lymphocyte culture-primed peripheral T cells were used as a source of Th. Thymocytes, which depend upon exogenous Th cells for activation, were used as a source of cytotoxic precursors. Data is presented that demonstrates that at least two pathways of T-T interaction can lead to the activation of cytotoxic lymphocytes. The first is an allogeneic effect, in which Th cells recognize and respond to alloantigens expressed on CTL.P. The second is the interaction of Th cells with syngeneic CTL.P, in which both cell types are thought to respond to alloantigens on stimulator cells. The latter interaction can be shown to be restricted by H-2-linked determinants when primed Th cells are used and allogeneic effects against thymocytes are minimized. Restricted interactions between unprimed Th cells and thymocyte CTL.P have never been observed. Mechanisms ...
PubMed journal article Identification and characterization of a human agonist cytotoxic T-lymphocyte epitope of human prostate-specific antige were found in PRIME PubMed. Download Prime PubMed App to iPhone, iPad, or Android
Cytotoxic T-cell clones were raised in CBA mice that recognised both A/X31 and A/JAP/305/1957 influenza virus. Here, we describe one CTL clone that recognises target cells infected with a recombinant vaccinia virus expressing influenza PB1.
The present study focused on three Gag CTL epitopes restricted by three common HLA alleles in Japanese people (24). The Gag protein is most commonly targeted by CTL-inducing HIV/AIDS vaccines (15). In our endogenous expression system, three A*0201-restricted epitope variants and one B*5101-restricted epitope variant escaped from the wild-type CTL recognition, and four A24-restricted epitope variants escaped from the A24-restricted 3R mutant-reactive CTL recognition. Intriguingly, two A*0201-restricted variants and three A24-restricted variants escaped from CTL killing when the gag clones were expressed endogenously in the target cells by the HIV-1 vector, despite the fact that the synthetic variant peptides were well recognized by the CTLs when loaded onto the MHC class I molecule exogenously. The peptide titration experiments have revealed that the strength of these variant peptides recognition was almost equivalent to that of the A*0201-restricted wild-type peptide or the A24-restricted 3R ...
PURPOSE OF REVIEW: Much of the current HIV-1 vaccine research focuses on harnessing the cytotoxic T-lymphocyte arm of the immune response. However, HIV-1 appears to have an unerring ability to evade cytotoxic T-lymphocyte responses, through the process of escape mutation, and thus the potential benefit of a cytotoxic T-lymphocyte-based vaccine remains uncertain. This review focuses on several recent studies that question whether escape mutation is always detrimental to the host, and may provide new hope for the success of a cytotoxic T-lymphocyte-based vaccine against HIV. RECENT FINDINGS: Several recent studies, in both natural HIV-1 infection and the SIV model, have identified examples of cytotoxic T-lymphocyte escape mutants that revert on transmission to individuals lacking the selecting major histocompatibility complex alleles. The obvious implication of these data is that some cytotoxic T-lymphocyte responses can only be evaded through escape mutations that actually reduce the replicative fitness
Virus-associated hematologic malignancies (EBV lymphoproliferative disease) and opportunistic infections (CMV) represent a major cause of hematopoietic stem cell and solid organ transplantation failure. Adoptive transfer of antigen-specific T lymphocytes appears to be a major and successful immunoth
Townsend, A R. and Skehel, J J., Influenza a specific cytotoxic t-cell clones that do not recognize viral glycoproteins. (1982). Subject Strain Bibliography 1982. 1222 ...
This is a multicenter expanded access protocol to provide human leukocyte antigen (HLA) partially-matched third-party allogeneic EBV-CTLs for the treatment of
Cytotoxic T lymphocyte (CTL) responses have been associated with protection from HIV-1 infection in people with a high degree of exposure to HIV and who show no serological evidence of HIV infection (HEPS, highly exposed persistently seronegative). However, it remains unclear how protective CTL responses could apparently develop in a minority of people, whilst the great majority of HIV-infected people make strong CTL responses yet progress to AIDS and death. In this paper we review the data which supports the hypothesis that the quality of the T-cell response, rather than its magnitude, may be an important factor that merits further investigation.
Previous studies showed an inverse correlation between the plasma viral load (pVL) and the frequency of some HIV-1-specific CTLs in HIV-1-infected individuals, indicating that these CTLs control HIV-1 in vivo (5, 28, 33). However, this correlation was not found in the case of many other HIV-1-specific CTLs (16, 25, 26), suggesting the possibility that the quality of HIV-1-specific CTLs is a critical factor for the control of HIV-1 in vivo. However, it is not easy to assess the quality of HIV-1-specifc CTLs. An assay to directly measure the ability of the CTLs to suppress HIV-1 replication in vitro is a very useful method to evaluate the ability of the CTLs to control HIV-1. A previous study using this assay demonstrated that the ability of HLA-B*5101-restricted HIV-1-specific CTLs to suppress HIV-1 replication is dependent on the epitope recognized by these CTLs (43). In addition, a recent study showed that HLA-A*2402-restricted Nef138-specific CTLs have a strong ability to suppress HIV-1 ...
Jeggo, M H. and Wardley, R C., Generation of cross-reactive cytotoxic t lymphocytes following immunization of mice with various bluetongue virus types. (1982). Subject Strain Bibliography 1982. 3115 ...
TY - JOUR. T1 - Negative and positive selection of antigen-specific cytotoxic T lymphocytes affected by the α3 domain of MHC I molecules. AU - Aldrich, Caria J.. AU - Hammer, Robert E. AU - Jones-Youngblood, Sharon. AU - Koszinowski, Ulrich. AU - Hood, Lee. AU - Stroynowski, Iwona T. AU - Forman D.M.D/Ph.D., James Morse. N1 - Copyright: Copyright 2018 Elsevier B.V., All rights reserved.. PY - 1991. Y1 - 1991. N2 - THE α1 and α2 domains of major histocompatibility complex (MHC) class I molecules function in the binding and presentation of foreign peptides to the T-cell antigen receptor and control both negative and positive selection of the T-cell repertoire1-3. Although the α3 domain of class I is not involved in peptide binding, it does interact with the T-cell accessory molecule, CDS (refs 4, 5). CDS is important in the selection of T cells as anti-CDS antibody injected into perinatal mice interfers with this process6. We previously used a hybrid class I molecule with the α1/α2 domains ...
A successful T cell immune response has two major products: effector T cells which directly or indirectly remove the antigens, and memory T cells, which allow a faster and more efficient recall response when challenged by related antigens. An important issue is whether costimulatory molecules on the antigen-presenting cells are involved in determining whether T cells will differentiate into effector or memory cells after antigenic stimulation. To address this issue, we have produced mice with targeted mutations of either the heat-stable antigen (HSA), or both HSA and CD28. We show that CD28/B7 and HSA provide two alternative costimulatory pathways for induction of immunological memory to influenza virus. Furthermore, our results revealed that B7 is essential for the generation of effector T cells from either naive or memory T cells, while HSA is not necessary for the generation of effector T cells. Our results demonstrate that the induction of memory T cells and effector T cells can utilize ...
Looking for online definition of T cytotoxic cell in the Medical Dictionary? T cytotoxic cell explanation free. What is T cytotoxic cell? Meaning of T cytotoxic cell medical term. What does T cytotoxic cell mean?
article{628449, abstract = {We describe here a limiting dilution analysis to determine cytotoxic T lymphocyte precursor (CTLp) frequencies against individual HLA-A or -B antigens. This assay is reproducible and showed that the CTLp frequency of an individual remains stable with time. Significant variations in CTLp frequency against the same alloantigen were found in different individuals and even in monozygotic twins, showing that these differences were not (completely) genetically determined. Within an individual, a wide range of CTLp frequencies can be found against different allo-antigens. Serologically cross-reactivity seems not to interfere in this assay. This LDA is a practicable tool for a systematic analysis of CTLp response against selected individual HLA-A or -B antigens and can be used for the selection of HLA mismatched donors for transplantation patients.}, author = {Zhang, Li and Li, Shu Guang and Vandekerckhove, Bart and Termijtelen, Annemarie and Van Rood, Joh J and Claas, Frans ...
Dendritic cells (DC) play a key role in the initiation of T cell-mediated immune responses and may therefore be successfully used in antiviral and antitumor vaccination strategies. Because both strength and duration of an immune response determines the outcome of a vaccination protocol, we evaluated the life span of DC-induced antiviral CTL memory against systemic and peripheral challenge infections with lymphocytic choriomeningitis virus (LCMV). We found that expansion and activation of CTL by DC was transient. Protection against systemic LCMV infection after DC immunization was relatively long-lived (,60 days), whereas complete protection against peripheral infection via intracerebral infection or infection into the footpad with LCMV, where rapid recruitment of effector T cells to the site of infection and elimination of viral pathogen plays a major role, was short-lived (,30 days). Protective immunity was most efficiently restored by administration of antigenic peptides via DC, rather than in ...
Looking for online definition of Cytotoxic T lymphocytes in the Medical Dictionary? Cytotoxic T lymphocytes explanation free. What is Cytotoxic T lymphocytes? Meaning of Cytotoxic T lymphocytes medical term. What does Cytotoxic T lymphocytes mean?
We have previously reported the establishment of cytotoxic T-cell lines from pancreatic cancer patients, by continuously stimulating tumor-draining lymph node cells with allogeneic pancreatic tumor cell lines. After the preliminary characterization of their phenotype and tumor specificity, detailed studies performed with one of the cell lines, W.D., show that it recognizes a specific antigen, a large and heavily glycosylated mucin molecule, expressed on pancreatic and breast tumors and tumor cell lines. Although this recognition appears major histocompatibility complex (MHC)-unrestricted, the antigen receptor used by the cytotoxic T cell is the alpha/beta heterodimer, typically found on MHC-restricted T cells. The target antigen is atypical, however, in its ability to directly bind and activate the T cells in the absence of self MHC, presumably by abundant and regularly repeated antigenic epitopes. These findings are important because they demonstrate a specific T-cell response against a human ...
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Few studies have examined longitudinal changes in human immunodeficiency virus type 1 (HIV)-specific cytotoxic T lymphocytes (CTL). To more closely define the natural history of HIV-specific CTL, we used HLA-peptide tetrameric complexes to study the longitudinal CD8(+) T-cell response evolution in 16 A*0201-positive untreated individuals followed clinically for up to 14 years. As early as 1 to 2 years after seroconversion, we found a significant association between high frequencies of A*0201-restricted p17(Gag/Pol) tetramer-binding cells and slower disease progression (P | 0.01). We observed that responses could remain stable over many months, but any longitudinal changes that occurred were typically accompanied by reciprocal changes in RNA viral load. Phenotypic analysis with markers CD45RO, CD45RA, and CD27 identified distinct subsets of antigen-specific cells and the preferential loss of CD27(+) CD45RO(+) cells during periods of rapid decline in the frequency of tetramer-binding cells. In addition we
Infection of genital epithelial cells with human papillomavirus (HPV) types 16 and 18 is closely associated with the development of cervical carcinoma. The transforming potential of these high-risk HPVs depends on the expression of the E6 and E7 early viral gene products. Since the expression of E6 and E7 is selectively maintained in premalignant and malignant cervical lesions these proteins are attractive candidates for immunotherapeutic and prophylactic strategies. This report describes the construction, characterization and the in vivo immunotherapeutic potential of recombinant Semliki Forest virus (SFV) expressing the HPV16 E6 and E7 proteins (SFV-E6E7). Western blot analysis and immunofluorescence staining demonstrated expression of E6 and E7 in BHK cells infected with SFV-E6E7. Immunization of mice with SFV-E6E7 resulted in an efficient in vivo priming of HPV-specific CTL activity. The induced CTL lysed murine tumor cells transformed with the HPV16 genome and EL4 cells loaded with an
OBJECTIVES: To investigate HLA class I allele frequencies in a Kenyan commercial sex worker (CSW) cohort, and to examine HIV-1 specific cytotoxic T lymphocyte (CTL) responses directed against epitopes derived from locally prevalent clade A virus. METHODS: PCR-single strand polymorphism HLA class I typing. Sequencing of novel alleles and examination of their distribution in the CSW cohort, and a low risk HIV uninfected cohort. The peptide-binding motif of a novel class I allele was predicted, and a panel of candidate CTL epitopes was synthesized whose functional significance was examined using ELISpot and Cr release assays. RESULTS: Class I HLA-A and B frequencies within the cohort are presented. Two novel class I alleles were found, HLA-B*4415 and HLA-Cw*0407. These two class I alleles were relatively common, both in the CSW cohort (2.1% and 3.3% respectively) and in a cohort of lower risk women (1.9% and 3.8% respectively). Allele HLA-B*4415 restricted CTL responses against a novel epitope (EEKAFSPEV)
TY - JOUR. T1 - Erratum. T2 - CD40 ligand-deficient mice generate a normal primary cytotoxic T-lymphocyte response but a defective humoral response to a viral infection (Journal of Virology 70:12 (8379)). AU - Whitmire, J. K.. AU - Slifka, M. K.. AU - Grewal, I. S.. AU - Flavell, R. A.. AU - Ahmed, R.. PY - 1997/1/1. Y1 - 1997/1/1. UR - http://www.scopus.com/inward/record.url?scp=0031033039&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0031033039&partnerID=8YFLogxK. M3 - Comment/debate. AN - SCOPUS:0031033039. VL - 71. JO - Journal of Virology. JF - Journal of Virology. SN - 0022-538X. IS - 2. ER - ...
In order to explore the potential of HLA-independent T cell therapy for human cytomegalovirus (HCMV) infections, we developed a chimeric antigen receptor (CAR) directed against the HCMV encoded glycoprotein B (gB), which is expressed at high levels on the surface of infected cells. T cells engineered with this anti-gB CAR recognized HCMV-infected cells and released cytokines and cytotoxic granules. Unexpectedly, and in contrast to analogous approaches for HIV, Hepatitis B or Hepatitis C virus, we found that HCMV-infected cells were resistant to killing by the CAR-modified T cells. In order to elucidate whether this phenomenon was restricted to the use of CARs, we extended our experiments to T cell receptor (TCR)-mediated recognition of infected cells. To this end we infected fibroblasts with HCMV-strains deficient in viral inhibitors of antigenic peptide presentation and targeted these HLA-class I expressing peptide-loaded infected cells with peptide-specific cytotoxic T cells (CTLs). Despite strong
Identification and characterization of antigen-specific T lymphocytes during the course of an immune response is tedious and indirect. To address this problem, the peptide-major histocompatability complex (MHC) ligand for a given population of T cells was multimerized to make soluble peptide-MHC tetramers. Tetramers of human lymphocyte antigen A2 that were complexed with two different human immunodeficiency virus (HIV)-derived peptides or with a peptide derived from influenza A matrix protein bound to peptide-specific cytotoxic T cells in vitro and to T cells from the blood of HIV-infected individuals. In general, tetramer binding correlated well with cytotoxicity assays. This approach should be useful in the analysis of T cells specific for infectious agents, tumors, and autoantigens. ...
TY - JOUR. T1 - Identification of HLA-A24 epitope peptides of carcinoembryonic antigen which induce tumor-reactive cytotoxic T lymphocyte. AU - Nukaya, I.. AU - Yasumoto, M.. AU - Iwasaki, T.. AU - Ideno, M.. AU - Sette, A.. AU - Celis, E.. AU - Takesako, K.. AU - Kato, I.. PY - 1999/1/5. Y1 - 1999/1/5. N2 - Carcinoembryonic antigen (CEA), which is expressed in several cancer types, is a potential target for specific immunotherapy. HLA-A24 is the most frequent allele among Japanese and is also frequently present in Asians and Caucasians. We tested CEA-encoded HLA-A24 binding peptides for their capacity to elicit anti-tumor cytotoxic T lymphocytes (CTL) in vitro. For this purpose, we used CD8+ T lymphocytes from peripheral blood mononuclear cells (PBMC) of a healthy donor and autologous peptide-pulsed dendritic cells as antigen-presenting cells. This approach enabled us to identify 2 peptides, QYSWFVNGTF and TYACFVSNL, which were capable of eliciting CTL lines that lysed tumor cells expressing ...
Strain AS rats respond with two populations of cytotoxic T lymphocytes to stimulation in vitro by the major histocompatibility complex (MHC)-incompatible strain HL rat tumor (HL-A2T2). One is specific for MHC alloantigens present on both HL-A2T2 and normal HL targets, the other is tumor specific. The activation of these killer cells requires helper T lymphocytes. The tumor-specific helper cells depend on syngeneic radioresistant accessory cells to present the tumor antigens in an immunogenic form. The appropriate helper-accessory cell interaction results in the production of soluble factors which then induce the maturation of precursor cells into effective killer cells. Studies with a procedure for inducing negative selection of T cells in vivo showed that short-term exposure to HL-A2T2 tumor induced selection only for TH but not cytotoxic T lymphocyte precursors (CTLp). Simultaneous injection of supernatants from concanavalin A-activated spleen cell cultures, however, did produce selection of ...
A Phase I-II Trial to Examine the Toxicity of CMV- and EBV- Specific Cytotoxic T Lymphocytes When Used for Prophylaxis Against EBV and CMV Disease in Recipients of CD34-Selected/T Cell-Depleted Stem Cell ...
CD40 expression on human melanoma (MM) was described previously (17 , 18) , but little was known about its biological relevance. Here, we report the functional expression of CD40 on a subset of MM in situ as well as by some MM cell lines in vitro. Specifically, we demonstrate a gradual loss of CD40 expression during melanoma progression in situ. We also found human MM cell lines established from immunogenic MM but not from advanced-stage metastatic tissue positive for the CD40 antigen, thus paralleling the down-regulation of CD40 expression on MM metastases in situ. These results are in line with previous reports that 50% of MM cell lines generated from primary tumors, but only a minority of cell lines derived from metastases express CD40 (18) . In CD40-positive but not in CD40-negative MM, the expression of this antigen was increased after stimulation with IFN-γ or TNF-α but not with IL-1β or CD40L. By FACS analysis, we found none of the MMs positive for CD40L (CD154) using two different ...
We have examined requirements for antigen presentation to a panel of MHC class I-and class II-restricted, influenza virus-specific CTL clones by controlling the form of virus presented on the target cell surface. Both H-2K/D- and I region-restricted CTL recognize target cells exposed to infectious virus, but only the I region-restricted clones efficiently lysed histocompatible target cells pulsed with inactivated virus preparations. The isolated influenza hemagglutinin (HA) polypeptide also could sensitize target cells for recognition by class II-restricted, HA-specific CTL, but not by class I-restricted, HA-specific CTL. Inhibition of nascent viral protein synthesis abrogated the ability of target cells to present viral antigen relevant for class I-restricted CTL recognition. Significantly, presentation for class II-restricted recognition was unaffected in target cells exposed to preparations of either inactivated or infectious virus. This differential sensitivity suggested that these H-2I ...
A cytotoxic T cell (also known as TC, cytotoxic T lymphocyte, CTL, T-killer cell, cytolytic T cell, CD8+ T-cell or killer T cell) is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways. Most cytotoxic T cells express T-cell receptors (TCRs) that can recognize a specific antigen. An antigen is a molecule capable of stimulating an immune response, and is often produced by cancer cells or viruses. Antigens inside a cell are bound to class I MHC molecules, and brought to the surface of the cell by the class I MHC molecule, where they can be recognized by the T cell. If the TCR is specific for that antigen, it binds to the complex of the class I MHC molecule and the antigen, and the T cell destroys the cell. In order for the TCR to bind to the class I MHC molecule, the former must be accompanied by a glycoprotein called CD8, which binds to the constant portion of the class I MHC molecule. ...
TY - JOUR. T1 - Identification of HER2/neu-derived peptide epitopes recognized by gastric cancer-specific cytotoxic T lymphocytes. AU - Kono, Koji. AU - Rongcun, Yang. AU - Charo, Jehad. AU - Ichihara, Fumiko. AU - Celis, Esteban. AU - Sette, Alessandro. AU - Appella, Ettore. AU - Sekikawa, Takayoshi. AU - Matsumoto, Yoshiro. AU - Kiessung, Rolf. PY - 1998. Y1 - 1998. N2 - We have derived HLA-A2.1-restricted, gastric cancer-specific cytotoxic T lymphocyte (CTL) lines by repetitive in vitro stimulation of tumor- associated lymphocytes (TAL) with autologous tumor cells. The HER2/neu specificity of these gastric cancer-specific CTLs was demonstrated using HER2/neu-transfected cell lines and HER2/neu-expressing tumors, and with a set of HER2/neu-derived peptide epitopes. Gastric cancer-specific CTLs specifically lysed autologous and allogeneic HLA-A2.1 +, HER2/neu+ gastric cancer cells, HER2/neu-transfected CIR/A2 cell lines (HLA-A2.1+, HER2+) and HLA-A2.1-transfected SW626 tumor cell lines ...
In the course of constructing a recombinant vaccinia virus encoding the influenza A nucleoprotein (NP) gene preceded by the hemagglutinin leader sequence, we isolated a single base-pair deletion mutant which gave rise to L+NP(1-159) in which only the first 159 amino acids were in frame. Despite this, when we infected target cells, we found that the point mutant was able to sensitize them for lysis not only by cytotoxic T cells recognizing residues 50-58 (the in-frame portion), but also by CTL to epitopes which are downstream of the mutation (366-374 and 378-386). Furthermore, normal C57BL/6 mice can be primed with the frameshift NP to recognize the immunodominant Db-restricted epitope 366-374 (which is out of frame). Experiments in which the mutant gene product was processed in the endoplasmic reticulum of target cells suggested that the apparent suppression occurred during polypeptide extension.
Cell-based therapies have intriguing potential for the treatment of a variety of neurological disorders. One such example is genetically engineered cytotoxic T lymphocytes (CTLs) that are being investigated in brain tumor clinical trials. The development of methods for CTL delivery is critical to their use in the laboratory and clinical setting. In our study, we determined whether CTLs can migrate through fibrin matrices and if their migration, survival, and function could be modulated by adding chemokines to the matrix. Our results indicated that CTLs can freely migrate through fibrin matrices. As expected, the addition of the monocyte chemotactic protein-1 (MCP-1), also known as chemokine C-C motif ligand 2 (CCL2), to the surrounding media increased egress of the CTLs out of the fibrin clot. Interleukin (IL) -2 and/or IL-15 embedded in the matrix enhanced T cell survival and further promoted T cell migration. The interleukin-13 receptor alpha 2 specific (IL-13R alpha2) T cells that traveled out of the
Background: Many determinants for a sustained response to lamivudine therapy have been reported but the role of I cell responsiveness remains unclear. The finding that lyrosine-methionine-aspartate-aspartate (YMDD) motif of the reverse transcriptase domain of hepatitis B virus (HBV) DNA polymerase carries a HLA-A2 restricted cytotoxic T lymphocyte (CII) epitope makes quantitative measurement of the numbers of peptide specific CTLs feasible using MHC tetramer-peptide complex staining. Aim: To investigate the correlation between anti-YMDD motif CTL activity and the efficacy of lamivudine therapy in HLA-A2 positive patients with chronic hepatitis B (CH-B). Methods: The function and phenotype of peptide and interleukin 2 expanded peripheral blood mononuclear cells were quantified by cell lytic assay and immunocytochemical analysis by staining with HLA-A2-peptide tetramer complexes. Results: After in vitro expansion, sustained responders had more potent CL responses against YMDD, YVDD, and YIDD, as ...
ABSTRACT: Cytotoxic T lymphocytes (CTL) responses are required to fight many diseases such as viral infections and tumors. At the same time, they can cause disease when induced inappropriately. Which factors regulate CTL and decide whether they should remain silent or react is open to debate. The phenomenon called cross-priming has received attention in this respect. That is, CTL expansion occurs if antigen is recognized on the surface of professional antigen presenting cells (APCs). This is in contrast to direct presentation where antigen is seen on the surface of the target cells (e.g. infected cells or tumor cells). Here we introduce a mathematical model, which takes the phenomenon of cross-priming into account. We propose a new mechanism of regulation which is implicit in the dynamics of the CTL: According to the model, the ability of a CTL response to become established depends on the ratio of cross-presentation to direct presentation of the antigen. If this ratio is relatively high, CTL ...
BACKGROUND Adoptive transfer of donor-derived EBV-specific cytotoxic T-lymphocytes (EBV-CTLs) can eradicate EBV-associated lymphomas (EBV-PTLD) after transplantation of hematopoietic cell (HCT) or solid organ (SOT) but is unavailable for most patients.METHODS We developed a third-party, allogeneic, off-the-shelf bank of 330 GMP-grade EBV-CTL lines from specifically consented healthy HCT donors. We treated 46 recipients of HCT (n = 33) or SOT (n = 13) with established EBV-PTLD, who had failed rituximab therapy, with third-party EBV-CTLs. Treatment cycles consisted of 3 weekly infusions of EBV-CTLs and 3 weeks of observation.RESULTS EBV-CTLs did not induce significant toxicities. One patient developed grade I skin graft-versus-host disease. Complete remission (CR) or sustained partial remission (PR) was achieved in 68% of HCT recipients and 54% of SOT recipients. For patients who achieved CR/PR or stable disease after cycle 1, one year overall survival was 88.9% and 81.8%, respectively. In ...
BACKGROUND Adoptive transfer of donor-derived EBV-specific cytotoxic T-lymphocytes (EBV-CTLs) can eradicate EBV-associated lymphomas (EBV-PTLD) after transplantation of hematopoietic cell (HCT) or solid organ (SOT) but is unavailable for most patients.METHODS We developed a third-party, allogeneic, off-the-shelf bank of 330 GMP-grade EBV-CTL lines from specifically consented healthy HCT donors. We treated 46 recipients of HCT (n = 33) or SOT (n = 13) with established EBV-PTLD, who had failed rituximab therapy, with third-party EBV-CTLs. Treatment cycles consisted of 3 weekly infusions of EBV-CTLs and 3 weeks of observation.RESULTS EBV-CTLs did not induce significant toxicities. One patient developed grade I skin graft-versus-host disease. Complete remission (CR) or sustained partial remission (PR) was achieved in 68% of HCT recipients and 54% of SOT recipients. For patients who achieved CR/PR or stable disease after cycle 1, one year overall survival was 88.9% and 81.8%, respectively. In ...
In this study, we evaluated the efficacy of human adjuvant vector cells for use as cancer vaccines in dogs and immunodeficient mice using human materials. We used allogeneic human cells, the CD1d-HEK293 cell line loaded α-GalCer and transfected with mRNA-encoding tumor antigen as artificial adjuvant vector cells. Our approach uses antigen-expressing vector cells expressing 2 antigens, which allows for host DC cross-presentation of tumor antigens to naïve T cells while simultaneously presenting iNKT cell ligand to iNKT cells (34, 35). This strategy induces activation of tumor antigen-specific CTLs as well as iNKT cells. An additional benefit of this strategy is the flexibility of mRNA transduction, which uses mRNA derived from tumor cell lines or tumors from third party patients and encodes for tumor antigens without the need for HLA matching. Furthermore, we have found in other studies that transfer of allogeneic cells expressing cell-associated tumor antigen and iNKT cell ligand induces not ...