Definition of homologous restriction factor in the Legal Dictionary - by Free online English dictionary and encyclopedia. What is homologous restriction factor? Meaning of homologous restriction factor as a legal term. What does homologous restriction factor mean in law?
RHEUMATOID ARTHRITIS. Rheumatoid arthritis (RA) is a chronic inflammatory disease that affects mainly diarthrodial joints and periarticular structures, and can acquire a systemic character. Rheumatoid arthritis affects approximately 1% of the world population, being two to three times more common in women.1. The etiology of RA has not been completely clarified. However, environmental and genetic factors have contributed to the development of the disease. In the early stages of RA, proliferation and edema of the synovial layer cells occur, with infiltration of B and T cells, macrophages, and granulocytes. The synovium thickens, and the joint becomes swollen and painful. With progression, synovial proliferation leads to the formation of pannus, a tissue that invades the articular cartilage and bone. Joint destruction is irreversible. Osteoclasts reabsorb bone, and there is release of proteolytic enzymes, such as metal-loproteinases, aggrecanases, and cathepsins, responsible for the destruction of ...
Results Brain pathological injury was the most serious at 24 h after reperfusion, The complement regulatory protein CD46 expression decreased gradually after local cerebral ischaemia-reperfusion injury, the lowest at 24 h after reperfusion, and returned to normal at 96 h after reperfusion.complement regulatory protein CD46 expression was negative correlated with brain pathological injury.. ...
Inherited deficiencies of several complement components strongly predispose to systemic lupus erythematosus (SLE) while deficiencies of complement inhibitors are found in kidney diseases such as atypical hemolytic uremic syndrome (aHUS). The exons of complement inhibitor genes CD46 and CFH (factor H) were fully sequenced using the Sanger method in SLE patients with nephritis originating from two cohorts from southern and mid Sweden (n = 196). All identified mutations and polymorphisms were then analyzed in SLE patients without nephritis (n = 326) and in healthy controls (n = 523). We found nonsynonymous, heterozygous mutations in CFH in 6.1% patients with nephritis, in comparison with 4.0% and 5.4% in patients without nephritis and controls, respectively. No associations of SLE or nephritis with common variants in CFH (V62I/Y402H/E936D) were found. Furthermore, we found two nonsynonymous heterozygous mutations in CD46 in SLE patients but not in controls. The A353V polymorphism, known to affect function
Background/Purpose: The influence of complement-mediated innate immune responses on cartilage and bone homeostasis in the ageing joint have not been studied. Inappropriate complement-mediated cell damage is prevented by membrane regulators such as CD59. Synovial tissue expression of CD59 is altered during inflammatory arthritis; elevated CD59 levels may be necessary to protect joint tissues. Roles of CD59 in maintaining tissue equilibrium and structural architecture within the synovial joint have not been described previously. Since CD59a is the primary regulator of membrane attack complex assembly in mice; we used CD59a-gene-deleted mice (CD59a-/-) as tools to unravel the function of CD59a in modulating age-related joint degeneration. Methods: Hind limbs were collected from C57BL/6J wild type (WT) and CD59a-/- mice at 8-, 20- and 50- weeks of age (6 to 10 mice/group). The Mankin score was used to classify the histopathological severity of osteoarthritic (OA) lesions. Three dimensional ...
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wistar complement wistar rat complement serum | order wistar complement wistar rat complement serum | How to use: wistar complement wistar rat complement serum | su
Simpson, R. J., Florida-James, G., Whyte, G. P., Middleton, N., Shave, R., George, K. & Guy, K. (2007). The effects of marathon running on expression of the complement regulatory proteins CD55 (DAF) and CD59 (MACIF) on red blood cells. European journal of applied physiology. 99, 201-204. doi:10.1007/s00421-006-0326-2. ISSN 1439-6327. ...
Simpson, R. J., Florida-James, G., Whyte, G. P., Middleton, N., Shave, R., George, K. & Guy, K. (2007). The effects of marathon running on expression of the complement regulatory proteins CD55 (DAF) and CD59 (MACIF) on red blood cells. European journal of applied physiology. 99, 201-204. doi:10.1007/s00421-006-0326-2. ISSN 1439-6327. ...
CRP seems to be not only a biomarker for atherosclerosis but also a mediator of plaque formation.3 By binding to enzymatically degraded low-density lipoprotein, CRP is able to activate the classical pathway of complement,13 serving as a potential link between complement activation and atherosclerosis.9,10 To protect against complement-mediated cell lysis, nucleated cells express complement inhibitor proteins on their surface. By upregulating the expression of these proteins in endothelial cells, CRP may serve to protect ECs from complement-mediated injury.. The ability of CRP to bind to nucleated cells and cause complement activation without cytolysis14 has been largely attributed to its ability to recruit the inhibitory plasma protein factor H.15 However, our results indicate that CRP may play a more active, protective role by stimulating the expression of DAF, CD46, and CD59 in endothelial cells. The kinetics of DAF expression were analyzed in greater detail because DAF seems to be the most ...
The complement system is a crucial mediator of inflammation and cell lysis after cerebral ischemia. However, there is little information about the exact contribution of the membrane attack complex (MAC) and its inhibitor-protein CD59. Transient focal cerebral ischemia was induced by middle cerebral artery occlusion (MCAO) in young male and female CD59a knockout and wild-type mice. Two models of MCAO were applied: 60 min MCAO and 48 h reperfusion, as well as 30 min MCAO and 72 h reperfusion. CD59a knockout animals were compared to wild-type animals in terms of infarct size, edema, neurological deficit, and cell death. CD59a-deficiency in male mice caused significantly increased infarct volumes and brain swelling when compared to wild-type mice at 72 h after 30 min-occlusion time, whereas no significant difference was observed after 1 h-MCAO. Moreover, CD59a-deficient mice had impaired neurological function when compared to wild-type mice after 30 min MCAO. We conclude that CD59a protects against ischemic
CD59 / Complement Regulatory Protein / Protectin Antibody - Without BSA and Azide, Mouse Monoclonal Antibody [Clone SPM616 ] validated in IHC, IF, FC (AH12772-100), Abgent
Scientists have discovered when a cancer-killing virus is injected in the bloodstream it hitches a ride on blood cells and evades attack from the immune sy
The group of cells in the body that are affected by the genetic defect that causes PNH. These cells all come from the same parent cell in the bone marrow. Since the genetic defect lies in the parent cell, all cells which come from the parent cell, (including red blood cells, white blood cells and platelets) are affected. The size of a PNH clone depends on the number of cells affected by PNH. A PNH clone is tested on a regular basis in order to identify whether a PNH clone has increased, decreased or is stable. ...
CD59, 50 µg. CD59 (also known as HRF20, protectin) is a 20 kDa glycoprotein attached to the plasma membrane by a glycosylphosphatidylinositol (GPI) anchor.
Mohamed Kharfan-Dabaja, MD, discusses the future of PNH treatment, the various symptoms that can present in PNH, and the challenges that still remain for further improving outcomes.
Studies confirm the prognostic value of ENoG testing performed between 3 and 14 days after onset of complete facial paralysis. ...
TY - JOUR. T1 - Assessing donor chimerism using flow cytometry in paroxysmal nocturnal haemoglobinuria after stem cell transplantation--a case report.. AU - Raja Sabudin, Raja Zahratul Azma. AU - Hussin, Noor Hamidah. AU - Chooi Fun, Leong. AU - Ainoon, O.. AU - Cheong, S. K.. PY - 2006/12. Y1 - 2006/12. N2 - Paroxysmal nocturnal haemoglobinuria (PNH) is an acquired haemopoietic stem cell disorder arising from somatic mutation of the X-linked PIG-A gene which leads to deficiency of the glycosylphosphatidylinositol (GP1) membrane anchor proteins such as CD 59 (MIRL: membrane inhibitor of reactive lysis) and CD 55 (DAF: decay accelerating factor). Allogeneic peripheral blood stem cell transplant (PBSCT) is a curative mode of treatment in symptomatic PNH patients. Assessment of donor chimerism for PBSCT can be performed by various methods including short tandem repeat loci (STR) and variable number of tandem repeats (VNTR). Flow cytometry, which is much cheaper and faster, also can be used to ...
Treatment for paroxysmal nocturnal hemoglobinuria in Richards Town, Bangalore, find doctors near you. Book Appointment Online, View Fees, Reviews Doctors for Paroxysmal Nocturnal Hemoglobinuria Treatment in Richards Town, Bangalore | Practo
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Paroxysmal nocturnal hemoglobinuria: Find the most comprehensive real-world symptom and treatment data on paroxysmal nocturnal hemoglobinuria at PatientsLikeMe. 9 patients with paroxysmal nocturnal hemoglobinuria experience fatigue, depressed mood, pain, anxious mood, and insomnia.
TY - JOUR. T1 - Molecular organization of C9 within the membrane attack complex of complement. Induction of circular C9 polymerization by the C5b-8 assembly. AU - Podack, E. R.. AU - Tschoop, J.. AU - Muller-Eberhard, H. J.. PY - 1982. Y1 - 1982. N2 - Evidence has been presented suggesting that during assembly of the membrane attack complex (MAC) of complement, the C5b-8 complex induces polymerization of C9. The C9 polymer was detected by sodium dodecyl sulfate (SDS) gel electrophoresis of MAC isolated from complement-lysed erythrocytes. It resembled the previously described polymerized C9 (poly C9) produced from isolated monomeric C9 by prolonged incubation at 37° C in that it was resistant to dissociation by SDS and reducing agents and had an apparent molecular weight of ~1.1 million. The presence of poly C9 in the MAC was further supported by the expression of identical neoantigens by the MAC and poly C9 and by the high C9 content of the MAC relative to its other constituents. Isolated C8 in ...
NEW HAVEN, Conn.--(BUSINESS WIRE)--Alexion Pharmaceuticals, Inc. (NASDAQ:ALXN) today announced the initiation of two Phase 3 trials of ALXN1210, a highly innovative, longer-acting anti-C5 antibody that inhibits terminal complement. The first trial is a Phase 3 open-label, multinational, active-controlled study of ALXN1210 compared to eculizumab (Soliris®) in complement inhibitor treatment-naïve patients with paroxysmal nocturnal hemoglobinuria (PNH).
... is established by flow cytometric analysis of CD55 and CD59 on leukocytes and erythrocytes.
Paroxysmal nocturnal haemoglobinuria (PNH) is a unique disorder in which a substantial proportion of the patients red cells have an abnormal susceptibility to activated complement. This results from the presence of a clone that originates from a haematopoietic stem cell bearing an acquired somatic mutation in the X-linked gene ...
Learn about paroxysmal nocturnal hemoglobinuria. What are the symptoms, the causes and how to treat this condition? What can we do to cope...
Feldman L. Triiodothyronine (T3) toxicosis and paroxysmal nocturnal hemoglobinuria: report of case. J Am Osteopath Assoc 1981;80(7):491. doi: 10.7556/jaoa.1981.80.7.491.. Download citation file:. ...
Protectin D1 also known as neuroprotectin D1 (when it acts in the nervous system) and abbreviated most commonly as PD1 or NPD1 is a member of the class of specialized proresolving mediators. Like other members of this class of polyunsaturated fatty acid metabolites, it possesses strong anti-inflammatory, anti-apoptotic and neuroprotective activity. PD1 is an aliphatic acyclic alkene 22 carbons in length with two hydroxyl groups at the 10 and 17 carbon positions and one carboxylic acid group at the one carbon position. Specifically, PD1 is an endogenous stereoselective lipid mediator classified as an autocoid protectin. Autacoids are enzymatically derived chemical mediators with distinct biological activities and molecular structures. Protectins are signaling molecules that are produced enzymatically from unsaturated fatty acids. Their molecular structure is characterized by the presence of a conjugated system of double bonds. PD1, like other protectins, is produced by the oxygenation of the ω-3 ...
The major limitation of organ transplantation is the shortage of available organs. Xenotransplantation is considered to be an effective way to resolve the problem. Immune rejection is a major hurdle for the successful survival of pig xenografts in primate recipients. Cytokines play important roles in inflammation and many diseases including allotransplantation, however, their roles in xenotransplantation have been less well investigated. We assessed the role of several cytokines in xenotransplantation using an in vitro model of human antibody-mediated complement-dependent cytotoxicity (CDC). Porcine aortic endothelial cells (PAECs) and porcine iliac endothelial cells (PIECs) were selected as target cells. The complement regulators (CD46, CD55 and CD59) and junction protein genes were assessed by real-time PCR, flow cytometry, or western-blotting assay. Flow cytometry assay was also used to evaluate C3 and C5b-9 deposition, as well as the extent of human IgM and IgG binding to PIECs. Gene silencing was
Severely anemic patients with PNH on treatment with Soliris™ can become transfusion-free with improved hemoglobin when switched to APL-2 monotherapy. Treatment-naïve patients with PNH show clinically meaningful improvements for all hematological parameters when treated with APL-2. CRESTWOOD, Ky. and WALTHAM, Mass., June 26, 2018 (GLOBE NEWSWIRE) -- Apellis Pharmaceuticals, Inc. (Nasdaq:APLS), a clinical-stage biopharmaceutical company focused on the development of novel therapeutic compounds to treat disease through the inhibition of the complement system, will provide clinical updates today on its two ongoing Phase Ib PNH studies during an R&D Day in New York between 2.00 pm and 5.00 pm.. Apellis is developing APL-2 for the treatment of PNH, a rare, acquired, potentially life-threatening disease characterized by complement-mediated thrombosis and hemolytic anemia. The Company believes that by targeting C3, APL-2 can improve hematological parameters in patients with PNH on treatment with C5 ...
陣發性夜間血紅素尿症(paroxysmal nocturnal haemoglobinuria, PNH)是一種罕見的造血幹細胞疾病,因後天基因突變而造成[1]。一般來說,正常紅血球的細胞膜上有幾種保護性蛋白質,例如:蛋白衰變加速因子(decay accelerating factor, CD55)以及溶解細胞膜抑制物(membrane inhibitor of reactive lysis, CD59),使紅血球不會因補體(免疫系統的一部分)的攻擊而破裂[1]。然而,PNH患者因為在X染色體上的phosphatidylinositol glycan A (PIG-A)基因發生突變,造成某些醣脂質,例如glycosylphosphatidylinositols (GPI)無法形成,而使紅血球上的保護性蛋白質無法藉著GPI結合在紅血球的細胞膜上[1]。紅血球沒有這些蛋白質的保護就容易因人體內補體系統的攻擊而破裂,引起持續、慢性的血管內溶血性疾病,這也是造成疾病症狀及後續嚴重併發症的原因[2-4 ...
Xenozoonosis, also known as zoonosis or xenosis, is the transmission of infectious agents between species via xenograft. Animal to human infection is normally rare, but has occurred in the past. An example of such is the avian influenza, when an influenza A virus was passed from birds to humans.[33] Xenotransplantation may increase the chance of disease transmission for 3 reasons: (1) implantation breaches the physical barrier that normally helps to prevent disease transmission, (2) the recipient of the transplant will be severely immunosuppressed, and (3) human complement regulators (CD46, CD55, and CD59) expressed in transgenic pigs have been shown to serve as virus receptors, and may also help to protect viruses from attack by the complement system.[34] Examples of viruses carried by pigs include porcine herpesvirus, rotavirus, parvovirus, and circovirus. Porcine herpesviruses and rotaviruses can be eliminated from the donor pool by screening, however others (such as parvovirus and ...
Speaking with your healthcare team about your condition and finding out what you can about the disease can be empowering and can help you understand how best to move forward. OneSource is a complimentary, personalized patient support program offered by Alexion, and tailored to the specific needs of people living with aHUS, gMG, HPP, LAL-D, NMOSD and PNH. Were here to help you learn, and were here to help you understand the options available to you.. ...
Definition of Epidemic haemoglobinuria with photos and pictures, translations, sample usage, and additional links for more information.
MI Update - Volume 12, Issue 4 is centered on immunology of the liver. Including articles of vein tolerance and development of regulator CD4 T-cells, IL-27R, and T-cell Immunity
A novel cell surface antigen has been identified on a wide range of lymphoid cells and erythrocytes. A mAb YTH 53.1 (CD59) against this antigen enhanced the lysis of human red cells and lymphocytes by homologous complement. Studies of reactive lysis using different species of C56, and of whole serum used as a source of C7-9, indicated that the inhibitory activity of the CD59 antigen is directed towards the homologous membrane attack complex. CD59 antigen was purified from human urine and erythrocyte stroma by affinity chromatography using the mAb YTH 53.1 immobilized on Sepharose, and, following transient expression of a human T cell cDNA library in COS cells, the corresponding cDNA also identified using the antibody. It was found that the CD59 antigen is a small protein (approximately 20 kD as judged by SDS-PAGE, 11.5 kD predicted from the isolated cDNA) sometimes associated with larger components (45 and 80 kD) in urine. The sequence of CD59 antigen is unlike that of other complement ...
This volume reviews the fundamental understanding of this potentially life-threatening disease and the advances in treatment that have been achieved with the use of the monoclonal antibody eculizumab. Although the PIGA gene has been known for many years, the mechanism of clonal dominance in paroxysmal nocturnal hemoglobinuria is still largely unknown. This book, Paroxysmal Nocturnal Hemoglobinuria, discusses the direction of continuing research in this area, as well as the potential for the development of management guidelines. It serves as a valuable source of information for both basic scientists and physicians, especially immunologists targeting GPI-anchored proteins and complements, and hematologists specializing in bone marrow failure. ...
SUMMARY In contrast to all other intrinsic abnormalities of the erythrocyte, paroxysmal nocturnal hemoglobinuria (PNH) is an acquired, not an inherited, disorder. PNH arises as a consequence of somatic mutation, involving one or more hematopoietic stem cells, of PIGA, a gene located on the X chromosome that is required for synthesis of the glycosylphosphatidylinositol (GPI) moiety that anchors some proteins to the cell surface. Consequently, all GPI-anchored proteins (GPI-APs) that are normally expressed are deficient on the mutant hematopoietic stem cells and their progeny. The complement-mediated intravascular hemolytic anemia and the resulting hemoglobinuria that are the clinical hallmarks of PNH are a consequence of deficiency of the GPI-anchored complement regulatory proteins, CD55 and CD59. Although PNH is a neoplastic (clonal) disease, it is not a malignant disease in that there is no exaggerated proliferation of neoplastic cells and replacement of marrow or spread to other tissues, and ...
Paroxysmal nocturnal hemoglobinuria (PNH) is a clonal bone marrow disorder, resulting from an acquired, somatic X-linked mutation of the PIG-A gene in an hematopoietic stem cell. Absence of PIG-A function in a cell prevents synthesis of the glycosylphosphatidylinositol (GPI) moiety, which anchors many different types of proteins to the cell membrane. Intravascular red cell destruction, the hallmark of the disorder, is caused by susceptibility of the abnormal erythrocyte to complement-mediated lysis; this sensitivity is due to lack of CD59, a potent inhibitor of the late components of complement and reactive lysis. In vitro studies from this laboratory have demonstrated transfer of GPI-linked proteins, CD55 and CD59, from normal to deficient cells and transfer is associated with resistance to hemolysis. Patients with PNH frequently require transfusion as their standard care. In addition, patients with all blood groups requiring transfusion will often receive compatible group O blood. Group O ...
Blood 1998 Dec 1;92(11):4439-45 Abstract quote Hemolytic anemia is a major feature of paroxysmal nocturnal hemoglobinuria (PNH). Intravascular red blood cell (RBC) destruction is caused by increased sensitivity of the abnormal erythrocyte to complement-mediated lysis, due to the GPI absence of a membrane-bound glycosylphosphatidylinositol (GPI)-linked protein, which functions as an inhibitor of reactive lysis (CD59). Both in vivo and in vitro models have suggested the feasibility of cell-to-cell transfer of GPI proteins, and patients with hemolysis could potentially benefit from transfer of CD59 to their deficient erythrocytes. We studied the ability of RBC components prepared from outdated packed RBC collections, as well as high-density lipoprotein (HDL) preparations, rich in CD55 and CD59, to promote protein transfer, as assessed by flow cytometry, immunoblotting, and susceptibility to complement-mediated lysis. By flow cytometry, CD55 and CD59 were present on RBC-derived microvesicles that ...
The kidney is particularly susceptible to complement-mediated injury in a number of clinical settings, and congenital deficiency or defects in the complement-regulatory proteins MCP and factor H are strongly associated with the development of renal disease. In the current study, we demonstrated that Crry (the murine homolog of MCP in the kidney) is the only membrane-bound regulator of complement expressed by murine TECs. Crry is expressed on the cell membrane, and its expression is concentrated in the basolateral portion of the cell. Polarized TECs regulate complement more efficiently on the basolateral surface of the cells than on the apical surface, in part because of Crry expression at this site. As with renal ischemia/reperfusion (I/R) (21), chemical hypoxia of the TECs causes a reduction in surface Crry levels, and the distribution within the cell is also altered.. Spontaneous complement activation on the surface of TECs is also controlled by endogenous factor H. When rH 19-20 was added to ...
Paroxysmal Nocturnal Haemoglobinuria (PNH) is an acquired hematopoietic stem-cell disorder related to the somatic mutation in PIG-A gene (X-chromosome). This genetic alteration results in partial or total deficiency of all proteins normally linked to the cell membrane by glycosylphosphatidyl-inositol (GPI). Flow cytometry provides an efficient diagnostic test in which the lack of GPI-anchored proteins is studied on the major blood cell populations ...
Paroxysmal Nocturnal Haemoglobinuria (PNH) is an acquired hematopoietic stem-cell disorder related to the somatic mutation in PIG-A gene (X-chromosome). This genetic alteration results in partial or total deficiency of all proteins normally linked to the cell membrane by glycosylphosphatidyl-inositol (GPI). Flow cytometry provides an efficient diagnostic test in which the lack of GPI-anchored proteins is studied on the major blood cell populations ...
... is a rare acquired, life-threatening disease of the blood. The disease is characterized by destruction of red blood cells (hemolytic anemia), blood clots (thrombosis), and impaired bone marrow function (not making enough of the three blood components). PNH affects 1-1.5 persons per million of the population and is primarily a disease of younger adults. The median age of diagnosis is 35-40 years of age, with occasional cases diagnosed in childhood or adolescence. PNH is closely related to aplastic anemia. In fact, up to 30% of newly diagnosed cases of PNH evolve from aplastic anemia. Similarly, the risk of developing PNH after treatment for aplastic anemia with immunosuppressive therapy (anti-thymocyte globulin and cyclosporine) is approximately 20-30%. The median survival after diagnosis is 10 years; however, some patients can survive for decades with only minor symptoms.. PNH occurs when mutations of a gene called PIG-A occur in a bone marrow stem cell. ...
Paroxysmal nocturnal hemoglobinuria (PNH) In this condition, the bone marrow--the soft spongy tissue that act as the blood manufacturing system for the entire body--produces defective red blood cells. The bodys natural defense system then destroys these defective red blood cells in a process is known as hemolysis.
The term "nocturnal" refers to the belief that hemolysis is triggered by acidosis during sleep. However, this observation was later disproved. In individuals with paroxysmal nocturnal hemoglobinuria, hemolysis has been shown to occur throughout the day, but the urine concentrated overnight produces the dramatic change in color.[1] It is most noticeable in the morning, upon passing urine that has accumulated in the bladder during the night.[2] ...
Paroxysmal Nocturnal Hemoglobinuria - Epidemiology Insights to 2025 is a market research report available at US $2950 for a Single User PDF License from RnR Market Research Reports Library.
TY - JOUR. T1 - The membrane attack complex of complement. T2 - Relation of C7 to the metastable membrane binding site of the intermediate complex C5b-7. AU - Preissner, K. T.. AU - Podack, E. R.. AU - Muller-Eberhard, H. J.. PY - 1985/1/1. Y1 - 1985/1/1. N2 - Isolated C7 (m.w. 120,000) in 1% deoxycholate (DOC) forms dimers with an apparent m.w. of 230,000 and a DOC-binding capacity of 82 mol per mol of dimer. Dimerization of C7 also occurs in the presence of DOC-phospholipid mixed micelles and eventuates in the insertion of C7 dimers into the lipid bilayer upon the removal of the detergent, C5b-7 complex formation in the fluid phase or on lipid vesicles likewise involves polymerization, C5b-7 sedimented with 17-40S, which suggests a dimeric to hexameric composition. In avidin-biotin binding experiments in which two differentially labeled forms of C5b,6 (biotinyl 125I-C5b,6, and 131I-C5b,6) were used in equimolar amounts to assemble C5b-7, more than 50% of the biotinyl 125I-C5b,6-containing ...
Decay-accelerating factor (DAF) is a 70,000 Mr protein that has been isolated from the membrane of red cells. The function of DAF is to inhibit the assembly of amplifying enzymes of the complement cascade on the cell surface, thereby protecting them from damage by autologous complement. We raised monoclonal antibodies to DAF and used them to study its distribution in cells from the peripheral blood of normal individuals and of patients with paroxysmal nocturnal hemoglobinuria (PNH), a disease characterized by the unusual susceptibility of red cells to the hemolytic activity of complement. The results of immunoradiometric assays and of fluorescence-activated cell sorter analysis showed that DAF was present not only on red cells but was widely distributed on the surface membrane of platelets, neutrophils, monocytes, and B and T lymphocytes. By Western blotting, we observed small but consistent differences in the Mr of DAF from the membranes of various cell types. Quantitative studies showed that ...
GPI-Anchored Proteins. The majority of eukaryotic cell membrane proteins have hydrophobic amino acids stretches that consists of a transmembrane polypeptide chain, which embeds the proteins into phospholipids double layer of the membrane [18]. GPI anchored proteins are membrane bound proteins. Several proteins are linked to the outer cell membrane leaflet by GPI anchor. This structure involves three key elements: a core containing a phosphatidylinositol (PI) moiety, one glucosamine and three mannose molecules and one ethanolamine phosphate unit [19]. A peptide bond links the C-terminus of the protein polypeptide to the last moiety. The GPI-anchor is created in the endoplasmic reticulum and attached to the polypeptide post-translational by a transaminase enzyme [20-21]. Molecular Genetic Background. Until date, all PNH patients have had genetic mutations in an X-linked gene known as PIG-A [22, 23,9]. The PIG-A gene product is initially required in the assembly of GPI anchors [24]. Consequently, a ...