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)

B-CLL patients have a high prevalence of autoimmune phenomena due to polyclonal autoantibodies (Abs) restricted to blood cell self-antigens (Ag) and progressively develop a severe hypogammaglobulinemia. Autoimmunity and immunodeficiency have been related to B-CLL biological properties and cellular origin. Three major issues have emerged: 1) the relevance of B cell receptor abnormalities. More specifically, the importance of the defective expression of CD79b which may explain the faint to virtually undetectable amounts of monoclonal sig, the anomalous signal transduction and the failure to present antigens (Ag). 2) the possibility that the relentless accumulation of B-CLL cells is also under microenvironmental influences. These are brought about by the interplay of cytokines produced through cell/cell contacts among malignant B cells, macrophages and T cells. 3) the view that the very properties of accumulating anergic self-reactive CD5+ B lymphocytes may provide a bridge between autoimmunity and immune incompetence. CD5+ malignant B cells influence the cytokine production by T cells, but are inefficient Ag presenting cells (APC). As such they are a hurdle to the production of normal Ab. However, by stimulating in vitro the CD40 molecule on the membrane of CLL cell with the CD40 ligand the inefficient APC is turned into an efficient APC. In vivo, such an activation may conceivably occur in specific environments like the spleen and favour the production by normal residual B-cells of polyclonal autoAb against red cell or platelet self Ag.
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PMID:Relationship between autoimmunity and immunodeficiency in CLL. 947 Oct 57

There is evidence indicating that autoreactive B cells constitute a substantial part of the B cell repertoire. This autoreactive repertoire secretes the so-called natural autoantibodies characterized by their broad reactivity mainly directed against well-conserved public epitopes. Their germinal origin is suggested by their early appearance during ontogeny, their expression of cross-reactive idiotopes, and structural studies of their sequence. As for the physiological role of the repertoire, it may play a major role as a first barrier of defense. It is presently unknown whether these polyreactive B cells could constitute a pre-immune template which, through an antigen-driven process, may be involved in the production of immune high-affinity antibodies. This autoreactive B cell repertoire frequently undergoes malignant transformation, although there is controversy concerning the reasons accounting for this. It has been postulated that the continuous challenge of this autoreactive repertoire by self-antigens could create propitious conditions for malignant transformation to occur. However, this hypothesis still needs to be substantiated. Chronic lymphocytic leukemia (CLL), the most frequent form of leukemia in western countries, is characterized by constant expression of the CD5 marker and low expression of surface membrane immunoglobulin (Ig) in B lymphocytes. CLL B lymphocyte is frequently committed for natural autoantibody secretion. Despite expressing the Epstein-Barr virus (EBV) receptor CLL B cells cannot be infected by the EBV virus, they overexpress the bcl-2 protein and they are unable to adequately respond when stimulated through the B cell receptor pathway. Autoimmune-associated phenomena are frequently observed in B-cell CLL. These autotoxic manifestations are mainly directed against hematopoietic cells. In most cases, autoantibodies against red blood cells are warm reactive polyclonal IgG. Immune thrombocytopenia is observed in about 2% of cases, but higher frequencies of increased platelet associated Igs have been reported. Pure red cell aplasia and autoantibodies against neutrophils are only rarely observed. This pattern is similar to that observed in primary immunodeficiency syndromes, in which immune thrombocytopenia, autoimmune hemolytic anemia, and pure red cell aplasia are frequently observed. The potential role of T cell defects in inducing autoimmune complications in B-cell CLL has been stressed by recent publications showing increased frequency of autoimmune hemolytic anemia in patients treated with purine nucleoside analogues. However, evidence is presently scarce concerning a functional impairment of T cells after administration of these drugs.
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PMID:Basic biology of autoimmune phenomena in chronic lymphocytic leukemia. 948 25

Bcl-3 is a proto-oncogene involved in the chromosomal translocation t(14;19) found in some patients with chronic lymphocytic leukemia. It shares structural similarities with and is a member of the IkappaB family of proteins. In this report, involvement of Bcl-3 in hematopoietic growth factor-stimulated erythroid proliferation and differentiation was examined. In TF-1 cells, an erythroleukemia cell line, granulocyte-macrophage colony-stimulating factor (GM-CSF) and erythropoietin (Epo) greatly enhanced Bcl-3 expression at both the protein and mRNA levels in association with stimulation of proliferation. Bcl-3 protein was also highly expressed in early burst-forming unit-erythroid (BFU-E)-derived erythroid precursors (day 7) and decreased during maturation (days 10 and 14), suggesting that Bcl-3 is involved in normal erythroid proliferation. In these hematopoietic cells, Bcl-3 was hyperphosphorylated. GM-CSF and Epo modulated the subcellular localization of Bcl-3. Upon stimulation of TF-1 cells with GM-CSF or Epo, the nuclear translocation of Bcl-3 was dramatically enhanced. Overexpression of Bcl-3 in TF-1 cells by transient transfection along with the NF-kappaB factors p50 or p52 resulted in significant induction of an human immunodeficiency virus-type 1 (HIV-1) kappaB-TATA-luceriferase reporter plasmid, demonstrating that Bcl-3 has a positive role in transactivation of kappaB-containing genes in erythroid cells. Stimulation with GM-CSF enhanced c-myb mRNA expression in these cells. Bcl-3 in nuclear extracts of TF-1 cells bound to a kappaB enhancer in the c-myb promoter together with NF-kappaB2/p52 and this binding activity was enhanced by GM-CSF stimulation. Furthermore, cotransfection of Bcl-3 with p52 or p50 in TF-1 cells resulted in significant activation of a c-myb kappaB-TATA-luceriferase reporter plasmid. These findings suggest that Bcl-3 may participate in the transcriptional regulation of certain kappaB-containing genes involved in hematopoiesis, including c-myb.
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PMID:Bcl-3 expression and nuclear translocation are induced by granulocyte-macrophage colony-stimulating factor and erythropoietin in proliferating human erythroid precursors. 969 11

Recent studies have improved our understanding of the cytogenesis, biology, and therapy of chronic lymphocytic leukemia (CLL). This review highlights this recent progress reported over the past year. We have improved our understanding of the cytogenetic abnormalities in CLL and soon may see identification of new tumor suppressor genes that may be deleted in the leukemia cells of a large number of patients with this disease. We have achieved a better understanding of the surface antigens that help govern the pattern of tissue-infiltration of leukemia cells in vivo. Studies on the immune pathophysiology of CLL are providing clues to potential mechanisms leading to the immunodeficiency associated with this disease. Combination chemotherapy with purine analogues is showing promise for improved efficacy in CLL. Finally, new therapies incorporating bone marrow transplantation, and possibly gene therapy, increasingly are being considered for the therapy of patients with this disease.
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PMID:Chronic lymphocytic leukemia. 974 30

Developing a secondary non Hodgkin's lymphoma (NHL) more than 12 months after treatment for first cancer, is uncommon. Secondary NHL occurs sometimes after chronic lymphatic leukemia or Hodgkin's disease. The 20 years cumulative incidence rate is 3-5% after Hodgkin's disease. Secondary NHL seems less frequent after any childhood cancer. Pertinent features of secondary NHL are a high percentage of patients with extranodal tumor sites (brain, digestive tractus), high grade histological subtype, phenotype B and advanced stage. But for identical histological type and stage, the prognosis of secondary NHL seems the same than de novo NHL ones. The incidence of secondary NHL is associated to individual parameters (age), first cancer (chronic lympho proliferative syndrome, Hodgkin's disease) and previous chemo- and/or radiotherapy. Immunodeficiency is probably the most important cofactor for the subsequent development of secondary NHL. However, secondary NHL differs from NHL of immunosuppressed patients (HIV+, posttransplant) because brain lymphoma are less frequent and immunodeficiency disorders unknown. Secondary NHL are also different of therapy-associated leukemias in the late occurrence after the first treatment and in the questionable role of cytotoxic agents given for the treatment of the first cancer.
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PMID:[Secondary non-Hodgkin's lymphomas]. 975 10

Over the past year, progress has been made in understanding of the physiology and disease associations of CD5+ (B1) B cells, although their exact role in pathogenesis remains unclear. Earlier studies on the negative function of CD5 within the B-cell receptor complex have been substantiated, and it seems likely that soon the signaling pathways used by this coreceptor will be elucidated. Progress in diagnosis, physiology, and etiopathogenesis of CD5+ malignancies has been made, particularly in B-cell chronic lymphocytic leukemia. The low-level expression of surface immunoglobulin has been explained by the mutations that occur in the associated CD79b. Two new potential tumor-suppressor genes have been identified in the hot spot of chromosome 13q, which provides an exciting step forward in understanding of the etiopathogenesis of some B-cell chronic lymphocytic leukemia. Activated signal transducers for activation of transcription factors molecules have been shown to be phosphorylated on different amino acids in B1 and chronic lymphocytic leukemia tumors, although the significance of this is, as yet, unclear. Finally, aberrant expression of CD40L by chronic lymphocytic leukemia T cells may contribute to the immunodeficiency that develops in these patients.
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PMID:CD5 B cells and B-cell malignancies. 991 51

CD7 co-expression by CD4 T cells has been reported to be higher in the Th1 compared with the Th2 functional subset. Clinical immunodeficiency and immune dysregulation are more prevalent in the advanced stages of B cell chronic lymphocytic leukaemia (B-CLL). To analyse this further 25 patients with B-CLL and 11 healthy subjects were examined for cell surface CD7 and intracellular IFN-gamma and IL-4 expression in the peripheral blood CD4+ T helper cell population. Significantly decreased CD7, IFN-gamma and IL-4 expression was observed in the patients with B-CLL (P < 0.001). While CD7 negativity and IL-4 expression were more frequent in the later stages of the disease, this did not attain statistical significance. These results suggest a possible explanation for the reduced cellular and humoral immunity in B-CLL.
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PMID:Reduced IL-4 and interferon-gamma (IFN-gamma) expression by CD4 T cells in patients with chronic lymphocytic leukaemia. 1040 9

Perianal infections caused by herpes simplex virus are common in immunocompromised patients. The cutaneous presentation in these patients is often atypical, overlaps with the clinical features of other diseases, poses a difficulty in diagnosis, and responds poorly to treatment. An immunocompromised patient with chronic lymphocytic leukemia, treated with oral corticosteroids, presented with chronic perianal ulcerations. This patient was referred for evaluation and treatment of "recalcitrant" pyoderma gangrenosum. Prompt diagnosis was possible when the clinical features were recognized and appropriate biopsy and cultures were obtained. We describe an atypical presentation of herpes simplex virus associated with both an endogenous and exogenous induced immunodeficiency, and stress the importance of routinely performing cultures on all perianal ulcerations and anal fissures to avoid the misdiagnosis, inappropriate treatment, and prolonged discomfort of these afflicted patients.
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PMID:Atypical presentation of herpes simplex virus in a patient with chronic lymphocytic leukemia. 1046 7

We report three cases of nodal peripheral T-cell lymphoma (PTCL) with Reed-Sternberg-like (RS-like) cells of B-cell pheno- and/or genotype. Histologic analysis in all cases revealed diffuse nodal effacement by atypical lymphoid cells of variable size. Two of the three cases had features of angioimmunoblastic T-cell lymphoma (AILT). Large mononuclear and binucleated cells with prominent eosinophilic nucleoli and abundant cytoplasm resembling classic RS cells and mononuclear variants were scattered throughout all biopsies. The lymphoma cells in the three cases were of T-cell lineage (CD3+, CD43+, and CD45RO+). The RS-like cells from all cases were CD30 and CD15 positive. In contrast to the neoplastic T cells, the RS-like cells lacked all T-cell markers and in two cases were positive for CD20. Epstein-Barr virus (EBV) latent membrane protein 1 (LMP1) and EBER 1 (2/2) were detected in the RS-like cells in all cases. The neoplastic T cells were negative for EBV. Polymerase chain reaction (PCR) analysis demonstrated clonal rearrangements of the T-cell receptor gamma chain gene in the three cases. PCR analysis of microdissected RS-like cells for immunoglobulin heavy chain gene rearrangements in cases 1 and 3 showed an oligoclonal pattern. The presence of RS-like cells in PTCL represents a diagnostic pitfall, because in one case this observation led to a misdiagnosis of Hodgkin's disease (HD). The oligoclonal expansion of EBV-infected cells may be related to underlying immunodeficiency associated with T-cell lymphomas and AILT in particular. This phenomenon may provide the basis for some cases of Hodgkin's disease after T-cell lymphomas and suggests that they are clonally unrelated neoplasms. The expression of LMP1 appears to be crucial for the immunophenotype and probably for the morphology of the RS and RS-like cells appearing in diverse lymphoid malignancies, including HD, chronic lymphocytic leukemia, and PTCL.
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PMID:Peripheral T-cell lymphoma with Reed-Sternberg-like cells of B-cell phenotype and genotype associated with Epstein-Barr virus infection. 1052 24

Since 1990 we have treated 60 patients with standard-dose fludarabine for chronic lymphocytic leukemia (B-CLL), on a compassionate basis. Three patients developed grade IV neurologic complications after treatment, with demyelination of white matter on magnetic resonance imaging (MRI) in patient # 1, diffuse demyelination, abnormal oligodendroglia and enlarged astrocytes at brain biopsy in patient no 2, and progressive multifocal leukoencephalitis (PML) with JC virus on brain biopsy in patient # 3. The neurotoxicity of fludarabine was often observed after administration of high doses (90-120 mg/m2). At standard doses (18-25 mg/m2) neurologic complications were observed in very few cases (0.2%). PML was observed in only 0.52% of patients with chronic lymphocytic leukemia (CLL), particularly those with advanced CLL. Our findings are consistent with the results of published studies and show an increase in neurologic complications in patients with advanced CLL treated with fludarabine. This increased vulnerability is probably multifactorial, but may be secondary to the immunodeficiency.
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PMID:Progressive multifocal leukoencephalitis (PML) in three patients treated with standard-dose fludarabine (FAMP). 1054 75


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