Zhang Y, Feng ZP, Naselli G, Bell F, Wettenhall J, Auyeung P, Ellis JA, Ponsonby AL, Speed TP, Chong MM, Harrison LC. MicroRNAs in CD4(+) T cell subsets are markers of disease risk and T cell dysfunction in individuals at risk for type 1 diabetes. Journal of autoimmunity 68 : 52 - 61(2016) PubMed (Grant IDs: 637338, 1004541, 1037321, 1026349 ...
A broad T cell receptor (TCR-) repertoire is required for an effective immune response. TCR-repertoire diversity declines with age. End-stage renal disease (ESRD) patients have a prematurely aged T cell system which is associated with defective T cell- mediated immunity. Recently, we showed that ESRD may significantly skew the TCR Vb-repertoire. Here we assessed the impact of ESRD on the TCR Vb-repertoire within different T cell subsets using a multi-parameter flow-cytometry-based assay, controlling for effects of ageing and CMV latency. Percentages of 24 different TCR Vb-families were tested in circulating naïve and memory T cell subsets of 10 ESRD patients and 10 age- and CMV-serostatus-matched healthy individuals (HI). The Gini-index, a parameter used in economics to describe the distribution of income, was calculated to determine the extent of skewing at the subset level taking into account frequencies of all 24 TCR Vb-families. In addition, using HI as reference population, the differential impact
Richard Jefferys, TAG. Recent research involving SIV-infected macaques has suggested that the early loss of a particular type of memory CD4 T cell (known as a "central memory" T cell or Tcm) may be a key predictor of the subsequent pace of disease progression. Tcm are a long-lived subset of memory T cells that can proliferate robustly in response to antigen. Tcm proliferation generates a fleet of T cells belonging to a shorter-lived subset called "effector memory" (Tem) cells. Tem are generally viewed as first-responders that can rapidly execute anti-pathogen functions, while Tcm provide a stem-cell like renewal source for new Tem if their numbers need to be bolstered. Studies in HIV-infected people have consistently shown a loss of Tcm and increase in Tem (which equates to a decrease in long-lived resting T cells and an increase in short-lived activated T cells), but whether changes in the numbers of different T cell subsets during early infection can predict disease progression has not been ...
Virgin and memory T cells reciprocally express high levels of the RA or the RO isoforms of CD45, respectively. In an examination of T cell expression of these two CD45 isoforms during human development, the RO+RA- "memory" T cells were infrequent in the newborn blood and spleen, but comprised approximately half of the T cells in adult tissues. These anticipated findings probably reflect the immunologic naivete of the newborn. Surprisingly, however, RO+RA- T cells were relatively abundant in fetal spleen and in cord blood samples from premature births, comprising approximately 25% and 10% of the T cells in these tissues, respectively. This early peripheral wave of RO+RA- T cells was composed of polyclonal T cells in both the CD4 and CD8 subpopulations. The fetal RO+ cells of CD4+ phenotype frequently expressed the CD25-alpha chain subunits that characterize high affinity IL-2 receptors, and were able to proliferate in response to exogenous IL-2. In further contrast with their RO+ memory T cell ...
A set of non-volatile storage elements is divided into subsets for erasing in order to avoid over-erasing faster erasing storage elements. The entire set of elements is erased until a first subset of the set of elements is verified as erased. The first subset can include the faster erasing cells. Verifying the first subset includes excluding a second subset from verification. After the first subset is verified as erased, they are inhibited from erasing while the second subset is further erased. The set of elements is verified as erased when the second subset is verified as erased. Verifying that the set of elements is erased can include excluding the first subset from verification or verifying both the first and second subsets together. Different step sizes are used, depending on which subset is being erased and verified in order to more efficiently and accurately erase the set of elements.
The C-type lectin CD161 is expressed by a large proportion of human T lymphocytes of all lineages, including a population known as mucosal-associated invariant T (MAIT) cells. To understand whether different T cell subsets expressing CD161 have similar properties, we examined these populations in parallel using mass cytometry and mRNA microarray approaches. The analysis identified a conserved CD161++/MAIT cell transcriptional signature enriched in CD161+CD8+ T cells, which can be extended to CD161+ CD4+ and CD161+TCR gamma delta+ T cells. Furthermore, this led to the identification of a shared innate-like, TCR-independent response to interleukin (IL)-12 plus IL-18 by different CD161-expressing T cell populations. This response was independent of regulation by CD161, which acted as a costimulatory molecule in the context of T cell receptor stimulation. Expression of CD161 hence identifies a transcriptional and functional phenotype, shared across human T lymphocytes and independent of both T cell ...
CD4+ T cells are critical for host defense but are also major drivers of immune-mediated disease. These T cells specialize to become distinct subsets and produce restricted patterns of cytokines, which are tailored to combat various microbial pathogens. Although classically viewed as distinct lineages, recent work calls into question whether helper CD4+ T cell subsets are more appropriately viewed as terminally differentiated cells or works in progress. Herein, we review recent advances that pertain to this topic and the mechanisms that contribute to helper CD4+ T cell commitment and plasticity. The therapeutic implications of these new findings are also considered.. ...
Immune cells act as TSA screeners in the intestine-tolerating commensal microbes and food antigens but remaining vigilant against attack. However, it has remained unclear how T cell precursors differentiate into the different cell types required to perform this balancing act. Now, Bilate et al. report that the T cell receptor (TCR) itself does not limit T cell fate to a single identity. The authors found that cells expressing a single TCR derived from a peripheral regulatory T cell (Treg) developed into either Tregs or CD4+CD8αα+ intraepithelial lymphocytes (CD4IELs) in the gut. This differentiation depended on cues from both the microbiota and the surrounding environment. ...
In contrast to the predetermination model, TCR-dependent models of effector fate specification have been advanced, which posit that a gradient of TCR signaling from weakest to strongest is involved in the generation of IL-17, IFN-γ, and innate γδ T cells, respectively (Fig. 1B, 1C). Efforts to test this model entailed manipulation of either the γδ TCR-selecting ligand or signaling molecules downstream from the TCR.. Although few γδ T cell ligands are known, one of the best-studied γδ T cell ligands is the nonclassical MHC class I molecule T10/T22, which requires β2-microglobulin (β2m) for its surface expression (43). To assess the role of T10/T22 ligand engagement in effector fate specification, B2m−/− mice were used, in which surface expression of T10/22 is indirectly attenuated. One caveat is that β2m deficiency does not completely eliminate the expression of T10/22 on the cell surface (22, 29), and the low levels of T10/T22 that remain might influence the development of ...
Citation: N/A Interpretive Summary: Technical Abstract: In order to identify cytokines with immunoregulatory functions in chickens, CD4+ hybridoma designated as P34 which spontaneously secretes various cytokines was developed. Rabbit antibody was developed against a P34 culture supernatant fraction with T-cell promoting activity and used to screen the P34 cDNA library. A cDNA encoding a 12kDa protein was identified and cloned into pBluescript vector. The amino acid sequence deduced from the cloned cDNA indicated a 143-amino acid precursor peptide. This 12kDa protein was expressed in many tissues including spleen, intestine and muscle using a reverse transcription-polymerase chain reaction (RT- PCR). Activation of spleen cells with concanavalin A enhanced the expression of this protein in a time dependent manner in Northern blot. Stable transfection of this gene in CHO and SF9 cells produced a biologically active protein which supported the growth of gamma delta T lymphocytes. In summary, a ...
Unconventional T cells Introduction T lymphocytes are characterized by the expression of the CD3 molecule and the associated T cell receptor for antigen
Description of disease T cell, peripheral. Treatment T cell, peripheral. Symptoms and causes T cell, peripheral Prophylaxis T cell, peripheral
These cells inhibit the activation phase of the immune response by suppressing the response of B cells (antibody producing cells) or of other T cells (killer T cells, helper T cells) to an antigen resulting in tolerance for the antigen by the host ...
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Looking for delta T lymphocyte? Find out information about delta T lymphocyte. a deposit of clay, silt, and sand formed at the mouth of a river where the stream loses velocity and drops part of its sediment load. No delta is formed if... Explanation of delta T lymphocyte
Gamma delta T cells (γδ T cells) are T cells that have a distinctive T-cell receptor (TCR) on their surface. Most T cells are αβ (alpha beta) T cells with TCR composed of two glycoprotein chains called α (alpha) and β (beta) TCR chains. In contrast, gamma delta (γδ) T cells have a TCR that is made up of one γ (gamma) chain and one δ (delta) chain. This group of T cells is usually much less common than αβ T cells, but are at their highest abundance in the gut mucosa, within a population of lymphocytes known as intraepithelial lymphocytes (IELs). The antigenic molecules that activate gamma delta T cells are still largely unknown. However, γδ T cells are peculiar in that they do not seem to require antigen processing and major-histocompatibility-complex (MHC) presentation of peptide epitopes, although some recognize MHC class Ib molecules. Furthermore, γδ T cells are believed to have a prominent role in recognition of lipid antigens. They are of an invariant nature and may be ...
CD4-CD8- (double negative [DN]) alpha/beta T cells are a largely uncharacterized subpopulation of unknown function. To investigate whether these cells are selected to recognize particular antigens or antigen-presenting molecules, DN alpha/beta T cells were purified from the peripheral blood of five normal donors and their T cell receptor (TCR) alpha and beta chains were examined. Random cloning of TCR alpha chains by single-sided polymerase chain reaction (PCR) amplification identified an invariant rearrangement between V alpha 24 and J alpha Q, with no N region diversity, which was expressed preferentially by DN alpha/beta T cells from all donors. Random cloning also identified a precise V alpha 7.2-J alpha (IGRJa14) rearrangement, with two variable amino acids encoded in the V-J junction, which was enriched in the DN alpha/beta T cell preparations from some, but not all, donors. Analysis of TCR beta chains by quantitative PCR amplification demonstrated that the expression of four V beta gene ...
TY - JOUR. T1 - Altered homeostasis and development of regulatory T cell subsets represent an IL-2R-dependent risk for diabetes in NOD mice. AU - Dwyer, Connor J.. AU - Bayer, Allison L. AU - Fotino, Carmen. AU - Yu, Liping. AU - Cabello-Kindelan, Cecilia. AU - Ward, Natasha C.. AU - Toomer, Kevin H.. AU - Chen, Zhibin. AU - Malek, Thomas. PY - 2017/12/19. Y1 - 2017/12/19. N2 - The cytokine interleukin-2 (IL-2) is critical for the functions of regulatory T cells (Tregs). The contribution of polymorphisms in the gene encoding the IL-2 receptor subunit (IL2RA), which are associated with type 1 diabetes, is difficult to determine because autoimmunity depends on variations in multiple genes, where the contribution of any one gene product is small. We investigated the mechanisms whereby a modest reduction in IL-2R signaling selectively in T lymphocytes influenced the development of diabetes in the NOD mouse model. The sensitivity of IL-2R signaling was reduced by about two- to threefold in Tregs from ...
CD4-CD8- (double negative [DN]) alpha/beta T cells are a largely uncharacterized subpopulation of unknown function. To investigate whether these cells are selected to recognize particular antigens or antigen-presenting molecules, DN alpha/beta T cells were purified from the peripheral blood of five normal donors and their T cell receptor (TCR) alpha and beta chains were examined. Random cloning of TCR alpha chains by single-sided polymerase chain reaction (PCR) amplification identified an invariant rearrangement between V alpha 24 and J alpha Q, with no N region diversity, which was expressed preferentially by DN alpha/beta T cells from all donors. Random cloning also identified a precise V alpha 7.2-J alpha (IGRJa14) rearrangement, with two variable amino acids encoded in the V-J junction, which was enriched in the DN alpha/beta T cell preparations from some, but not all, donors. Analysis of TCR beta chains by quantitative PCR amplification demonstrated that the expression of four V beta gene ...
Kakita, N., Kanto, T., Itose, I., Kuroda, S., Inoue, M., Matsubara, T., Higashitani, K., Miyazaki, M., Sakakibara, M., Hiramatsu, N., Takehara, T., Kasahara, A. and Hayashi, N. (2012), Comparative analyses of regulatory T cell subsets in patients with hepatocellular carcinoma: A crucial role of CD25−FOXP3− T cells. Int. J. Cancer, 131: 2573-2583. doi: 10.1002/ijc.27535 ...
Results Th17 cells were decreased in the peripheral blood of RA patients, while OA patients had surprisingly an altered ratio of CD25+Tregs and Tr1 cells in circulation. In synovial tissues Th17 cells, TFH and regulatory T cell subsets were enriched among CD4+ T cells in RA as compared to OA patients, while frequencies of Th1 cells were similar. RA patients had higher serum levels of IL-17, IL-10 and BAFF, while serum IL-21 was elevated in both RA and OA patients. Importantly, serum levels of IL-17, IL-10 and BAFF were enhanced only in patients with active RA or with detectable autoantibodies. Moreover, BAFF and IL-17 levels in synovial fluid were also higher in RA as compared to OA patients, while IL-10 concentrations were similar. B cells from synovial fluid spontaneously released high amounts of IgG in the absence of CD4+ helper T cells, and regulatory T cell subsets were unable to suppress B cell IgG production.. ...
The generation of T helper cells in vitro requires macrophages or macrophage-derived factors such as genetically related macrophage factor (GRF) or nonspecific macrophage factor (NMF). However, there is a basic difference of T helper cell induction when using particulate antigens. The present study demonstrates that this difference is based on the activation of two different T cell subsets. GRF activates short-lived T1 cells which amplify the induction of T2 cells, which are the helper cell precursors. Thus, the genetic restriction of T helper cell induction seen with soluble antigen or GRF lies on the level of macrophage or GRF interaction with T1 cells. NMF (or macrophages) and particulate antigens directly activate the helper cell precursor (T2) indicating no requirement for T1-T2 cooperation. The direct activation of the helper cell precursor with particulate antigens does not require histocompatible macrophages or NMF from histocompatible macrophages. The present results may explain some of the
Objectives Evaluate the number and distribution of circulating CD4+ T lymphocytes and their CD4+ naïve T cells (TN), central memory (TCM), non-terminated effector memory (TNTEM) and terminated effector memory (TTEM) T cells subsets in a population of recently diagnosed DMARD naive RA patients before and along the first 6 months of methotrexate (MTX) treatment. ...
Our lab studies the basic processes of T lymphocyte development and activation. We are interested in the concepts underlying lineage decisions that govern the the maturation of different T cell subsets as well as memory T cells. The information is important in understanding the balance between protective- vs. auto-immunity.. ...
TCR gamma/delta, PerCP-eFluor™ 710, clone: eBioGL3 (GL-3, GL3), eBioscience™ 100μg; PerCP-eFluor™ 710 TCR gamma/delta, PerCP-eFluor™ 710,...
alpha beta TCR Mouse anti-Human, FITC, Clone: WT31, eBioscience™ 25 tests; FITC alpha beta TCR Mouse anti-Human, FITC, Clone: WT31, eBioscience™ Primary...
Denne rapport beskriver en metode til at fremkalde kronisk eksperimentelt autoimmunt tørt øje i Lewis rotter gennem immunisering med...
Maloney began by explaining that CAR-T cells produced from distinct T-cell subsets differ in potency. NSG mice bearing Raji tumors (0.5x10 6tumor cell inoculation; day 0) were treated with human CAR-T cells manufactured from distinct T-cell subsets (on day 7). CAR-T cells produced from CD8 +T CMcells were highly potent ( Sommermeyer et al.2015).. Engineering selected T-cell subsets could enhance potency and allow delivery of the same cell product in all patients, potentially providing more uniform data on dose response and toxicity.. Pre-clinical studies have established that a defined composition of CD8 +T CMderived and CD4 +derived CAR T-cells provides optimal potency.. ...
Experimental work has shown that T cells of the immune system rapidly and specifically respond to antigenic molecules presented on the surface of antigen-presenting-cells and are able to discriminate between potential stimuli based on the kinetic parameters of the T cell receptor-antigen bond. These antigenic molecules are presented among thousands of chemically similar endogenous peptides, raising the question of how T cells can reliably make a decision to respond to certain antigens but not others within minutes of encountering an antigen presenting cell. In this theoretical study, we investigate the role of localized rebinding between a T cell receptor and an antigen. We show that by allowing the signaling state of individual receptors to persist during brief unbinding events, T cells are able to discriminate antigens based on both their unbinding and rebinding rates. We demonstrate that T cell receptor coreceptors, but not receptor clustering, are important in promoting localized rebinding, and show
يصف هذا التقرير طريقة للحث على جفاف المناعة الذاتية المزمن التجريبي العين في الفئران لويس من...
Chattopadhyay, P. K. and Roederer, M. 2005. Immunophenotyping of T Cell Subpopulations in HIV Disease. Current Protocols in Immunology. 65:12.12:12.12.1-12.12.15. ...
This patent search tool allows you not only to search the PCT database of about 2 million International Applications but also the worldwide patent collections. This search facility features: flexible search syntax; automatic word stemming and relevance ranking; as well as graphical results.
Sigma-Aldrich offers abstracts and full-text articles by [M Lahn, H Kalataradi, P Mittelstadt, E Pflum, M Vollmer, C Cady, A Mukasa, A T Vella, D Ikle, R Harbeck, R OBrien, W Born].
Induction of IFN-γ- and TNF-α-secreting CD8+ T cell subpopulations upon DC priming.PBMC from volunteer CVD4000#65 were co-cultured with DC alone (media), or p
T cell: Type of leukocyte (white blood cell) that is an essential part of the immune system. T cells are one of two primary types of lymphocytes - B cells being the second type-that determine...
In order to discuss all the subsets of a given set, let us introduce the following terminology. We shall call the original set the universal set, one-element subsets will be called unit sets, and the set which contains no members the empty set. We do not introduce special names for other kinds of subsets of the universal set. As an example, let the universal set U consist of the three elements {a, b, c}. The proper subsets of U are those sets containing some but not all of the elements of U. The proper subsets consist of three two-element sets namely, {a, b}, {a, c}, and {b,... ...
Gammadelta T cells are found largely within the epithelium and recognize antigens differently than their alphabeta T cell counterparts. TCR delta-/- knock out mice exhibit a rapid tumor onset, along with increased tumor incidence. Although limited, research demonstrates that nutrients and bioactive food components can influence gammadelta T cell cytotoxicity, cytokine secretion, and proliferative capacity, and the results are nonetheless intriguing. Among other functions, gammadelta T cells play a role in immunosurveillance against malignant cells, as shown by the T cell receptor (TCR)delta-/- knock out mice that exhibit a rapid tumor onset and increased tumor incidence. Some common dietary modifiers of gammadelta T cell numbers or activity are apple condensed tannins, dietary nucleotides, fatty acids, and dietary alkylamines. A recent clinical study demonstrated that ingesting a fruit and vegetable juice concentrate increased the number of circulating gammadelta T cells. Clinical studies also document
Thymic selection of natural killer-1+ natural T cells that express alpha beta T cell receptors requires a conserved beta 2-microglobulin-associated molecule, presumably CD1d, displayed by CD4+8+ thymocytes. Here we demonstrate that positive selection of natural T cells occurs independent of transporters associated with antigen presentation-1 (TAP-1) function. Moreover, natural T cells in TAP-1o/o mice are numerically expanded. Several H-2 class Ib molecules function in a TAP-independent manner, suggesting that if expressed in TAP-1o/o thymocytes, they could play a role in natural T cell development. Of these class Ib molecules, H-2TL is expressed by TAP-1o/o thymocytes. Moreover, we find that thymi of TL+ mice congenic or transgenic for H-2T18 also have a numerically expanded natural T cell repertoire compared with TL- mice. This expansion, as in TAP-1o/o thymi, is evident in each of the limited T cell receptor V beta chains expressed by natural T cells, suggesting that TL and CD1d impact ...
The authors have demonstrated compartment differences between T cell immunity in the bronchoalveolar space and the periphery. These include a predominant presence of effector memory T cells and regulatory CD4+ T cells in BAL, and a higher percentage frequency of antigen-specific CD4+ T cells against influenza virus, S pneumoniae and M tuberculosis in BAL compared to peripheral blood. Our data has also demonstrated that HIV-infected individuals have impaired pulmonary CD4+ T cell immunity, which is characterised by lower proportions of total CD4+ T cells and impaired antigen-specific BAL CD4+ T cell response to influenza virus and M tuberculosis antigens.. Consistent with previous observations,21 we noticed that BAL CD4+ and CD8+ T cells were predominantly of effector memory phenotype irrespective of HIV status, while peripheral blood T cell phenotypes were distributed among naive, central memory, effector memory and terminal effector. Effector memory T cells migrate to the lung following antigen ...
NK and gammadelta T cells can eliminate tumor cells in many experimental models, but their effect on the development of tumors caused by virus infections in vivo is not known. Polyomavirus (PyV) induces tumors in neonatally infected mice of susceptible strains and in adult mice with certain immune deficiencies, and CD8+ alphabeta T cells are regarded as the main effectors in anti-tumor immunity. Here we report that adult TCRbeta knockout (KO) mice that lack alphabeta but have gammadelta T cells remain tumor-free after PyV infection, whereas TCRbeta x delta KO mice that lack all T cells develop tumors. In addition, E26 mice, which lack NK and T cells, develop the tumors earlier than TCRbeta x delta KO mice. These observations implicate gammadelta T and NK cells in the resistance to PyV-induced tumors. Cell lines established from PyV-induced tumors activate NK and gammadelta T cells both in culture and in vivo and express Rae-1, an NKG2D ligand. Moreover, these PyV tumor cells are killed by NK cells in
T cells, in particular CD4+ T cells, have been implicated in mediating many aspects of autoimmune inflammation. However, current evidence suggests that the role played by CD4+ T cells in the development of rheumatoid inflammation exceeds that of activated proinflammatory T-helper (Th)1 effector cells that drive the chronic autoimmune response. Subsets of CD4+ T cells with regulatory capacity, such as CD25+ regulatory T (Treg) cells and Th2 cells, have been identified, and recent observations suggest that in rheumatoid arthritis the function of these regulatory T cells is severely impaired. Thus, in rheumatoid arthritis, defective regulatory mechanisms might allow the breakdown of peripheral tolerance, after which the detrimental Th1-driven immune response evolves and proceeds to chronic inflammation. Here, we review the functional abnormalities and the contribution of different T cell subsets to rheumatoid inflammation.
Intellicyt Corporation®, Part of the Sartorius Group. 5700 Pasadena Ave. NE, Albuquerque, NM 87113. A critical process in bio-manufacturing of adoptive cell therapies such chimeric antigen receptor (CAR) T and tumor infiltrating lymphocyte (TIL) therapies is the ex vivo expansion of T cells. Recent clinical studies show a correlation between in vivo expansion and persistence of infused T cells and patient outcomes. Additional studies show that a subset of functional memory T cells including T memory stem cells (Tscm), central memory T cells (Tcm) and other less differentiated T cell subsets are responsible for the majority of in vivo expansion and persistence leading to increased anti-tumor responses. This suggests that ex vivo protocols generating higher percentages of Tscm and Tcm in the total cell product will lead to significant clinical improvements in adoptive cell therapies. To address the need to monitor T cell phenotype and function for improved ex vivo expansion protocols and other ...
by Barbara Stranger, Hu X, Kim H, Raj T, Brennan PJ, Trynka G, Teslovich N, Slowikowski K, Chen WM, Onengut S, Baecher-Allan C, De Jager PL, Rich SS, Stranger BE, Brenner MB, Raychaudhuri S. Genome-wide association studies (GWAS) and subsequent dense-genotyping of associated loci identified over a hundred single-nucleotide polymorphism (SNP) variants associated with the risk of rheumatoid arthritis (RA), type 1 diabetes (T1D), and celiac disease (CeD). Immunological and genetic studies suggest a role for CD4-positive effector memory T (CD+ TEM) cells in the pathogenesis of these diseases. To elucidate mechanisms of autoimmune disease alleles, we investigated molecular phenotypes in CD4+ effector memory T cells potentially affected by these variants. In a cohort of genotyped healthy individuals, we isolated high purity CD4+ TEM cells from peripheral blood, then assayed relative abundance, proliferation upon T cell receptor (TCR) stimulation, and the transcription of 215 genes within disease loci ...
TY - JOUR. T1 - CD161 (NKR-P1A) costimulation of CD1d-dependent activation of human T cells expressing invariant Vα24JαQT cell receptor α chains. AU - Exley, Mark. AU - Porcelli, Steven. AU - Furman, Margo. AU - Garcia, Jorge. AU - Balk, Steven. PY - 1998/9/7. Y1 - 1998/9/7. N2 - A population of human T cells expressing an invariant Vα24JαQ T cell antigen receptor (TCR) α chain and high levels of CD161 (NKR-P1A) appears to play an immunoregulatory role through production of both T helper (Th) type 1 and Th2 cytokines. Unlike other CD161+ T cells, the major histocompatibility complex-like nonpolymorphic CD1d molecule is the target for the TCR expressed by these T cells (Vα24(invt) T cells) and by the homologous murine NK1 (NKR- P1C)+ T cell population. In this report, CD161 was shown to act as a specific costimulatory molecule for TCR-mediated proliferation and cytokine secretion by Mα24(invt) T cells. However, in contrast to results in the mouse, ligation of CD161 in the absence of TCR ...
An Australian group found that Tregs were elevated in thirty individuals with Fukuda for chronic fatigue syndrome (CFS).[4] The same group found elevated Tregs in a multiple sclerosis comparison study.[5]. However, a study that used the Revised Canadian Consensus Criteria (2010) criteria found Tregs were depleted in 76 people with ME/CFS.[6]. A second study in Japan also found decreased Tregs in 41 people who met both the Canadian Consensus Criteria and the International Consensus Criteria as compared to age- and gender-matched healthy controls.[7]. It is worth noting that such seemingly contradictory results are often found in the systemic autoimmune diseases in which T cell subsets are often studied. Even in illnesses with well-established biomarkers, age, gender, and time since onset lead to significant variability.[8]. ...
This research study is being carried out to study a new way to possibly treat HIV. T‐cells are one of the white blood cells used by the body to fight HIV. CD8 T‐cells are a type of T‐cell used by the body to detect and kill cells which have been infected by foreign viruses or organisms, including the HIV virus. CD8 T‐cells must identify the HIV virus in order to kill it. Because HIV is constantly changing the way it looks to the CD8 T‐cells, some of the HIV virus escapes detection and is not killed by the CD8 T‐cells.. This research study uses a T cell receptor (TCR) protein specific for HIV (SL9 TCR) and adds it to the CD8 T‐cells in the laboratory in order to help the CD8 T‐cells recognize the constantly changing HIV virus and make it able to fight HIV more efficiently. TCR stands for T cell receptor. TCRs are found on the surface of T cells and allow the T cells to recognize other cells. Laboratory studies have shown that when CD8 T‐cells are modified with SL9 TCRs, they ...
CD8hiCD57+ T cells have previously been described as effector memory T cells with minimal expansion capacity and high susceptibility to activation-induced cell death. In contrast, we demonstrate here that CD8hiCD57+ T cells are capable of rapid expansion using multiple techniques including [3H]thymidine uptake, flow cytometric bead-based enumeration and standard haemocytometer counting. Previous reports can be explained by marked inhibition of activation-induced expansion and increased 7-amino-actinomycin D uptake by CD8hiCD57+ T cells following treatment with CFSE, a dye previously used to measure their proliferation, combined with specific media requirements for the growth of this cell subset. The ability of CD8hiCD57+ T cells to further differentiate is highlighted by a distinct cytokine profile late after activation that includes the unexpected release of high levels of interleukin 5. These data indicate that CD8hiCD57+ T cells should not be considered as "end-stage" effector T cells ...
possible extrathymic T cells (i.e. CD56þ T cells and CD57þ T Therefore, we used adrenalectomized mice in an attempt to cells) [9,10]. It was found that cell populations could be classified identify possible influences on the circadian rhythm [17]. These into two groups: one group with daytime rhythm includes granu- mice lost such circadian rhythms, implying some hormonal reg- locytes, monocytes, NK cells, extrathymic T cells, gd T cells, and ulation. However, because of impaired mobility, they also lost the CD8þ cells. The other, with night rhythm, includes conventional T variation of their physical activity round the clock. Changes in the and B cells, ab T cells, and CD4þ cells. It is well known that NK activity of the autonomic nervous system might affect leucocyte cells, extrathymic T cells and gd T cells are involved in natural subsets, some of them carrying adrenergic or cholinergic receptors immunity and are more primitive than conventional T (and ab T) [11,12]. There are many reports ...
Maturation of T cells in the thymus involves input from a number of signaling pathways; their combined input determines whether thymic precursor cells will differentiate into mature αβ or γδ T cells. This Journal Club article highlights recent research showing that the role of Notch signaling in human T cell maturation differs from that in mice. In mice, reducing Notch gene dosage in vivo promotes γδ T cell differentiation. In humans, an increase in Notch activity early in development will trigger γδ T cell development. This research emphasizes how the molecular events controlling T cell development are fundamentally different in humans and mice.. ...
Cellular immune responses elicited by vaccination are complex and require polychromatic analysis to accurately characterize the phenotype and function of rare, responding cells. Technical challenges and a lack of instrument standardization between research sites have limited the application of polychromatic cytometry in multicenter clinical trials. Two previously developed six-color T cell subset immunophenotyping reagent panels deliberately designed to accommodate three additional low frequency functional measurements were compared for their reproducibility of staining across three different flow cytometers. We repeatedly measured similar T cell subset frequencies between the two reagent panels and across the three different cytometers. Spectral overlap reduced sensitivity in two of the three open measurement channels (PE [IL-2] and APC [IFN gamma]) for one reagent combination, particularly in subsets with low cytokine expression. There was no significant interassay variation for measurements ...