Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We searched for evidence that immunodeficiency in graft-versus-host disease (GVHD) is in part due to alloimmune damage to lymph nodes. We used immunoperoxidase techniques to stain T-cell subsets, pan-B cells, and follicular dendritic reticular cells (FDRC) in frozen sections of lymph nodes from 80 marrow graft recipients (56 with GVHD, 11 autografts, and 13 allografts without GVHD). We found that 46% of the GVHD patients had reversed CD4:CD8 ratios and only 13% of non-GVHD patients had such disturbed ratios (p = 0.006). Pan-B (CD22) cell labeling was present in the follicular regions of 73% of patients without GVHD and only 53% of patients with GVHD (p = 0.05). Focal FDRC staining was geographically concordant with clusters of B cells in 88% of cases (p less than 10(-7)). These data confirm that disturbed intranodal CD4:CD8 ratios are present more frequently in GVHD patients than in non-GVHD patients or in autografted patients. They suggest more delayed follicular B-cell reconstitution in GVHD patients. They show an extremely tight association of FDRC with clusters of B cells in the recovering lymph node, as in the developing fetal node. We hypothesize that the lack of follicular dendritic cells may contribute to dysfunctional B-cell maturation by ablating orderly antigen presentation and clonal expansion in the lymph node cortex.
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PMID:Abnormal CD4:CD8 ratios and delayed germinal center reconstitution in lymph nodes of human graft recipients with graft-versus-host disease (GVHD): an immunohistological study. 150 36

Immunodeficiency caused by HIV infection probably results from profound dysregulation of normal T lymphocyte properties by the virus. Despite description of the virus cytopathicity and numerous modifications in T cell functions, such as perturbation of antigen receptor signaling, CD4 downregulation, and induction of apoptosis, the precise mechanisms underlying the disruption of normal immune responses have not yet been elucidated. In the present study, we show that HIV-1-infected lymphocytes of the CEM cell line (either latent or virus-producing) and HIV-1-infected CD4+ lymphocytes have several membrane proteins with altered glycosylation patterns. Using lectins with specificity for different carbohydrate moieties, we could demonstrate the presence of two exposed nonsialylated disaccharides: a terminal Gal beta 1-->3GalNAc and a terminal Gal beta 1-->4GlcNAc. In particular, CD45, one of the major T cell glycoproteins, appeared to be partially sialylated on N- and O-linked carbohydrate moieties. Concerning the latter, PNA lectin which recognizes nonsialylated terminal Gal beta 1-->3GalNAc might precipitate up to 75% of the total tyrosine phosphatase activity displayed by CD45 molecules from one latently HIV-1-infected CEM cell line. Since CD45 glycoproteins are thought to play an important regulatory role in cell-to-cell interactions owing to their variable extracellular region and because they may regulate membrane signaling through their intracellular phosphatase domains, we suggest that these altered CD45 molecules may present an abnormal signal for natural ligands such as the B-cell-specific surface receptor CD22, thus perturbing the normal immune response in HIV-1-infected individuals.
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PMID:Altered sialylation of CD45 in HIV-1-infected T lymphocytes. 812 60

High-grade B-cell-type non-Hodgkin's lymphomas are observed in 5% to 8% of patients positive for the human immunodeficiency virus. Nearly all cases belong to one of the three major histologic types: centroblastic or large noncleaved cell, immunoblastic and Burkitt's lymphoma, or small noncleaved cell. Some cases that are polymorphic are termed high-grade B-cell, not otherwise specified (NOS). The authors determined the immunophenotype of each histologic category of acquired immunodeficiency syndrome (AIDS)-related non-Hodgkins' lymphoma and sought a relationship with the presence of the Epstein-Barr virus (EBV). B-cell differentiation antigens, activation marker expression (human leukocyte antigen-DR, CD10, CD19, CD20, CD21, CD22, CD23, CD25, CD30, CD38), and epithelial membrane antigen were analyzed. The clonality was determined by the detection of cytoplasmic immunoglobulin, surface immunoglobulin, and the analysis of joining region (JH) immunoglobulin gene configuration by Southern blot. Epstein-Barr virus was detected either by Southern blot analysis using BamHI W probe fragment or by in situ hybridization with EBV-encoded RNA transcripts-1 specific probe. The immunophenotypic and genotypic results were compared with the morphology results and with the presence or absence of EBV. Burkitt's lymphomas were associated with EBV in 50% of cases, were monoclonal, and expressed mostly immunoglobulin (Ig) MK, CD10, CD19, CD20, CD22, and CD38. This immunophenotypic profile closely resembled those of the centroblastic cases (large noncleaved cell), in which EBV was absent. Epstein-Barr virus was associated with 90% of immunoblastic cases, and only CD10, CD20, and CD38 were expressed. CD71 was expressed in all categories of non-Hodgkin's lymphoma, and CD21 and CD23 were rarely expressed. Two cases of immunoblastic lymphoma and one case of high-grade B-NOS were polyclonal regarding JH rearrangement, but EBV tested with 1.9-Kb Xhol fragment was clonal. No significant immunophenotypic changes were noted in relation to the presence of EBV. Such studies comparing morphology, immunophenotype, and genotype could help classify and better understand the pathogenesis of AIDS-related non-Hodgkin's lymphoma.
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PMID:Immunophenotypic and genotypic analysis of acquired immunodeficiency syndrome-related non-Hodgkin's lymphomas. Correlation with histologic features in 36 cases. French Study Group of Pathology for HIV-Associated Tumors. 820 68

From September 1984 through December 1991, of those with human immunodeficiency virus infection seen at the acquired immune deficiency syndrome unit of the Centro di Riferimento Oncologico, Aviano, Italy, 71 patients had systemic non-Hodgkin's lymphomas. The most frequent histotypes were small noncleaved cell, anaplastic large cell (ALC) CD30/BerH2+, and large cell immunoblastic. In 22 representative cases of these histotypes, including 9 of small noncleaved cell, 9 of ALC CD30/BerH2+, and 4 of immunoblastic non-Hodgkin's lymphomas, Epstein-Barr virus genetic information was assessed by in situ hybridization and correlated with histologic and immunophenotypic findings. Expression of B-cell associated markers, usually including CD19, CD20, CD22, CDw75, and CD74, was found in 17 of the 22 evaluated cases. All small noncleaved cell and immunoblastic cases and four cases of ALC lymphomas expressed B-cell immunophenotypes, whereas the remaining ALC cases were immunologically undetermined. In situ hybridization detected Epstein-Barr virus in 12 of 22 cases (54.5%). Seven of nine ALC lymphomas were positive, as were three of five small noncleaved cell type (Burkitt's lymphoma), one of four small noncleaved cell type (non-Burkitt's variant), and one of four large cell immunoblastic type. The results of this study indicate that Epstein-Barr virus genomes might be identified in more than 50% of the evaluated high grade non-Hodgkin's lymphomas; this association occurred significantly more often in the small noncleaved cell lymphomas resembling endemic Burkitt's lymphoma (60%) and with ALC CD30/BerH2+ lymphomas (77.8%). These findings support the notion that Epstein-Barr virus may play a role in the development of non-Hodgkin's lymphomas in a proportion of human immunodeficiency virus-infected patients.
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PMID:Demonstration of Epstein-Barr viral genomes by in situ hybridization in acquired immune deficiency syndrome-related high grade and anaplastic large cell CD30+ lymphomas. 838 22

Haptoglobin is an acute phase protein showing a genetic polymorphism with 3 major types: Hp 1-1, Hp 2-1, and Hp 2-2. In this study, flow cytometric analysis demonstrated that all three haptoglobin types bind to CD22 on human B-lymphocytes with equal affinity. Comparison of reference values for lymphocyte subsets in peripheral blood and bone marrow showed significant differences between haptoglobin types. Haptoglobin 2-2 is associated with higher peripheral B-lymphocyte counts (P < 0.001) and CD4+ T-lymphocyte counts (P < 0.05). In bone marrow, CD4+ T-cell percentages were highest (P < 0.001) but B-cell percentages were lowest (P < 0.001) in haptoglobin 2-2 type. A negative correlation between serum haptoglobin 1-1 concentration and peripheral B-cell counts was observed (r = -0.663). Our results suggest that haptoglobin is involved in lymphocyte distribution. The present findings are a potential cause of over- or underestimation of lymphocyte subset counts in the clinical staging of immunodeficiency diseases.
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PMID:Distribution of lymphocyte subsets in bone marrow and peripheral blood is associated with haptoglobin type. Binding of haptoglobin to the B-cell lectin CD22. 912 41

Many B cell abnormalities have been reported in human immunodeficiency virus (HIV)-infected patients, including changes in the expression of mu, gamma, and CD22 molecules on the cell surface. Phenotypic changes in these markers on B cells isolated from HIV-seropositive patients with high or low levels of plasma viremia were measured. The phenotypic changes in B cells isolated from such patients were compared with the markers on B cells isolated from HIV-seronegative individuals using three-color flow cytometry. HIV patients showed a reduction in the proportion of mature B cells isolated from peripheral blood mononuclear cells compared with B cells isolated from HIV-seronegative individuals. An increase in the proportion of B cells expressing both mu and gamma molecules on the cell surface was also seen in association with high-HIV plasma viremia. A low plasma viral load was accompanied by a reduction in the proportion of B cells expressing both mu and gamma molecules to a level comparable to those seen in HIV-seronegative individuals. HIV-seropositive individuals demonstrated an increase in the proportion of committed B cells, as indicated by an increase in the proportion of B cells expressing gamma molecules. This observation may explain the poor humoral response of HIV seropositive patients to neo-antigens. Our results demonstrate that phenotypic changes indicative of in vivo B cell activation and an increase in immature cells are associated with HIV infection, particularly with a high plasma viral load. Phenotypic changes in B cell markers may correlate with functional deficits of B cells.
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PMID:Association of phenotypic changes in B cell lymphocytes and plasma viral load in human immunodeficiency virus-infected patients. 962 83

The phenotypic analysis of human umbilical cord blood (CB) mononuclear cells is important to study their maturity and differentiation regarding their transplantable capacity. In this work we have studied differential expression of B cell antigens on CD5-/HLA-DR+ B cells (B1b, B2) and CD5+/HLA-DR+ cells (Bla) from the CB (n=6) and adult peripheral blood (PB) (N=6). CD5-PE, HLA-DR-PerCP and FITC labelled anti-B cell MoAb panel of the 6th International Workshop on Human Differentiation Antigens were used for detection of B cell subpopulations. FacsCalibur (B-D) flow cytometer was used for evaluation of samples. CB Bla (CD5/HLA-DR++) cells proved to be positive with CD9, CD19, CD20, CD21, CD22, CD23, CD24, CD32, CD39, CD45RA, CD76, CD79, MHC-II, IgM and anti Ig light chains MoAbs. CB B1b (CD5-/HLA-DR+) cells reacted with CD9, CD19, CD20, CD21, CD22, CD23, CD24, CD32, CD39, CD45RA, CD79, MHC-II, and IgM MoAbs. PB B cells (B2) expressed CD19, CD20, CD21, CD22, CD24, CD32, CD37, CD39, MHC-II and CD79 Ags. Unlike to the PB the CB B lymphocytes proved to be predominantly B1 cells representing a new-born B cell repertoire. Besides expressing many B cell antigens both the CB Bla and B1b cells showed CD9+, CD45RA+, IgM+ immature, "naive" B cell phenotype. Functionally, B1 cells are capable producing polyreactive IgM and natural autoantibodies but not IgG. This antibody profile might be insufficient regarding the recipient humoral immune defense result in more severe immunodeficiency after CB transplantation.
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PMID:Immunophenotypic characterisation of cord blood B-lymphocytes. 991 47

Infection of genetically susceptible mice with the LP-BM5 mixture of murine leukemia viruses including an etiologic defective virus (BM5def) causes an immunodeficiency syndrome called murine AIDS (MAIDS). The disease is characterized by interactions between B cells and CD4(+) T cells resulting in polyclonal activation of both cell types. It is known that BM5def is expressed at highest levels in B cells and that B cells serve as viral APC. The CD19-CD21 complex and CD22 on the surface of B cells play critical roles as regulators of B cell responses to a variety of stimuli, influencing cell activation, differentiation, and survival. CD19 integrates positive signals induced by B cell receptor ligation by interacting with the protooncogene Vav, which leads to subsequent tyrosine phosphorylation of this molecule. In contrast, CD22 negatively regulates Vav phosphorylation. To analyze the role of CD19, CD21, Vav, and CD22 in MAIDS, we infected mice deficient in CD19, CD21 (CR2), Vav-1, or CD22 with LP-BM5 murine leukemia viruses. Infected CR2(-/-) mice developed MAIDS with a time course and severity indistinguishable from that of wild-type mice. In contrast, CD19 as well as Vav-1 deficiency restricted viral replication and suppressed the development of typical signs of MAIDS including splenomegaly, lymphadenopathy, and hypergammaglobulinemia. Finally, CD22 deficiency was found to accelerate MAIDS development. These results provide novel insights into the B cell signaling pathways required for normal induction and progression of MAIDS.
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PMID:CD19 signaling pathways play a major role for murine AIDS induction and progression. 1242 39

Primary effusion lymphoma (PEL) or body cavity-based lymphoma (BCBL) is a unique subgroup of B-cell lymphomas that exhibits exclusive or dominant involvement of serous body cavities without a detectable tumor mass. We present a case of a PEL/BCBL that exclusively involved the peritoneal cavity of a 58-year-old immunocompetent male with hepatitis C virus (HCV)-related liver cirrhosis. The lymphoma cells were large, highly atypical and expressed CD19, CD20, CD22, CD10, HLA-DR, and CD45 with kappa light chain restriction. Unlike typical PEL/BCBL, human herpesvirus type 8/Kaposi sarcoma herpes virus (HHV-8/KSHV) genomic sequence was not present in the lymphoma cells and there was no serologic evidence of human immunodeficiency virus (HIV) infection. This is the fourth reported case of HHV-8 negative, HIV negative PEL/BCBL in a patient with associated HCV-related cirrhosis and review of these cases showed some consistent clinicopathological features, i.e. exclusive involvement of the peritoneal cavity and phenotypic expression of B-cell associated antigens in contrast to the generally null phenotype PEL/BCBL. The occurrence of these cases suggests that HCV may play an etiological role in a subcategory of PEL/BCBL not associated with HHV-8.
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PMID:HIV and HHV-8 negative primary effusion lymphoma in a patient with hepatitis C virus-related liver cirrhosis. 1469 39

Primary effusion lymphoma (PEL) is recognized as a unique clinicopathological entity associated with human herpesvirus 8 (HHV-8), and it occurs almost exclusively in human immunodeficiency virus (HIV)-infected individuals. In the majority of PEL cases, Epstein-Barr virus (EBV) has been found in the tumor cells as well. We describe here an elderly HIV seronegative female patient with PEL in the pleura and pericardium not associated with HHV-8 or EBV. Cytologic examinations of the pleural effusion revealed large lymphoma cells with immunophenotypes positive for CD8, CD10, CD19, CD20, CD22, CD24, CD45, and HLA-DR but negative for CD30 and surface immunoglobulin. Chromosome analysis showed complicated abnormalities including add(3)(q27). Immunoglobulin gene rearrangement was detected by Southern blotting; however, c-myc, Bcl-2, and Bcl-6 genes were not rearranged. The patient was treated with a modified CHOP (cyclophosphamide, hydroxydoxorubicin, oncovine, and prednisolone) regimen, and achieved remission. Recurrence of PEL in the pericardium as effusion lymphoma was found 3 months after the discontinuation of CHOP. After approximately 1 year of intermittent multiagent salvage therapy for pericardial recurrences, a treatment that resulted in a partial response, 3 cycles of monotherapy with sobuzoxane were administered. At the time of this report the patient had been free from PEL for more than 18 months without chemotherapy.
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PMID:Durable remission by sobuzoxane in an HIV-seronegative patient with human herpesvirus 8-negative primary effusion lymphoma. 1516 97


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