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Query: UMLS:C0021051 (immunodeficiency)
 71,517 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using the S49 T-cell lymphoma system for the study of immunodeficiency diseases, we characterized several variants in purine salvage and transport pathways and studied their responses to the cytotoxic action of adenosine (5-20 micron) in the presence of adenosine deaminase (ADA) inhibitors. Both an adenosine transport deficient mutant and a mutant lacking adenosine (ado) kinase activity are resistant to the cytotoxic effects of adenosine up to 15 micron. Variants lacking hypoxanthine-guanine phosphoribosyl transferase or adenine phosphoribosyltransferase are sensitive to the killing action of adenosine. We monitored the intracellular concentrations of purine and pyrimidine nucleotides, orotate, and PPriboseP in mutant and wild-type cells following the addition of adenosine and an ADA inhibitor. We conclude that at low concentrations, adenosine must be phosphorylated to deplete the cell of pyrimidine nucleotides and PPriboseP and to promote the accumulation of orotate. These alterations account for one mechanism of adenosine toxicity.
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PMID:Analysis of adenosine-mediated pyrimidine starvation using cultured wild-type and mutant mouse T-lymphoma cells. 30 79

The Epstein-Barr virus (EBV) has been classically associated with nasopharyngeal carcinoma and Burkitt's lymphoma, a monoclonal B-cell non-Hodgkin's lymphoma. Since the EBV genome has also been found in post-transplant lymphomas and lymphomas arising in individuals infected with the human immunodeficiency virus, evidence has now accumulated that EBV might be the initiator of a multi-step process leading from polyclonal B-cell hyperplasias to monoclonal lymphoma. In a retrospective study of 60 T-cell lymphomas of various types, we found EBV DNA in 21 (35%) using Southern- and/or dot-blot techniques. Eight of 14 nodal samples of angio-immunoblastic lymphadenopathy (57%) were shown to harbour detectable EBV DNA. The tumour with the next highest frequency, 47% (7/15 cases analyzed) was pleomorphic T-cell lymphoma, medium- and large-cell type; EBV was found both in nodal and in extranodal lymphomas of this type. Lymphoepitheloid (Lennert's) lymphoma and large-cell anaplastic lymphoma were positive in 2/5 and 3/8, respectively, of the cases analyzed. No viral DNA could be demonstrated in 3 T-immunoblastic and 5 T-lymphoblastic lymphomas. Clonotypic analysis revealed monoclonal as well as oligoclonal virus populations. Our data suggest that, at least in some of these entities, the presence of the EBV genome might be due to secondary mechanisms such as escape from immune surveillance.
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PMID:Prevalence of Epstein-Barr virus DNA in different T-cell lymphoma entities in a European population. 131 68

Bovine leukemia virus (BLV) is the etiologic agent of leukemia in cattle and is believed to cause decreases in milk productivity, fertility, and life span in infected cows. BLV is a type C retrovirus in the Oncovirinae subfamily. It is most closely related to human T-cell lymphoma/leukemia virus type I (HTLV-I) and type II (HTLV-II). Since the polymerase chain reaction (PCR) provides rapid and efficient amplification of DNA sequences, primers were designed to amplify regions of the polymerase (pol) and pX genes specific for BLV targets. These sets of primers consistently amplified as few as 10 copies of BLV DNA contained in a plasmid in the background of 1 microgram of either human or bovine chromosomal DNA. In addition, no amplification products were detected from cell lines infected with HTLV-I, HTLV-II, or human immunodeficiency virus type 1 or 2 by the BLV PCR systems. Samples of peripheral blood mononuclear cells from 18 cows, previously determined to be serologically positive or negative, were correctly identified in a blind study as containing proviral DNA by use of the BLV primers and probes. Cloning and sequencing of amplified products revealed finite sequence variations among a previously cloned BLV isolate, the wild-type virus, and the published genome. Reverse transcriptase-directed PCR with the primers for both BLV pol and BLV pX was performed on plasma from a BLV-infected cow and detected in vivo BLV RNA expression. In summary, we have developed a specific and sensitive assay using PCR for the detection and identification of BLV infections; this assay can now be applied to clinical and basic research questions in veterinary medicine.
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PMID:Amplification and analysis of specific DNA and RNA sequences of bovine leukemia virus from infected cows by polymerase chain reaction. 137 Aug 47

The majority of lymphomas in the setting of acquired, iatrogenic, or congenital immunodeficiencies are B-cell lymphoproliferations. We describe a rare T-cell lymphoma in a fulminantly ill patient infected with human immunodeficiency virus type 1 (HIV-1). The T-cell nature of the process was defined genotypically (monoclonal T-cell receptor beta-chain [CT beta] rearrangement) and phenotypically (CD45RO+, CD4+, CD5+, CD25+, CD8-, CD3- and negative for a variety of B-cell and monocyte markers). The CD4+, CD25+ (interleukin-2 receptor [IL-2R]) phenotype with production of IL-2 and IL-2R RNA is analogous to human T-lymphotropic virus type I (HTLV-I)-associated adult T-cell leukemia/lymphoma (ATLL); however, no HTLV-1 could be detected. Southern blot analysis did demonstrate monoclonally integrated HIV-1 within the tumor genome. Furthermore, the tumor cells were producing HIV p24 antigen as shown by immunohistochemistry. This is the first case of acquired immunodeficiency syndrome (AIDS)-associated non-Hodgkin's lymphoma in which HIV-1 infection may have played a central role in the lymphocyte transformation process.
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PMID:Acquired immunodeficiency syndrome-associated T-cell lymphoma: evidence for human immunodeficiency virus type 1-associated T-cell transformation. 137 87

During 1987-1988, a seroprevalence study of the human immunodeficiency virus (HIV-1) and the human T-cell lymphoma/leukemia virus (HTLV-I/II) was performed among Detroit intravenous drug users unaffiliated with substance abuse programs. Seroprevalence data along with patient demographic information were compared to a similar study performed in 1985-1986. In the earlier study, 12 (12.5%) of 96 individuals tested positive for HIV-1. Of the 74 available negative samples retested in 1987-1988 for retroviruses, 7 (9.5%) tested positive for HTLV-I/II. Thus, the overall retroviral (HIV-1, HTLV-I/II) seropositive rate for 1985-1986 was 22%. In 1987-1988, 11 (15.7%) of 70 individuals tested positive for HIV-1 and 7 (10%) tested positive for HTLV-I/II. Concomitant infection with both viruses was found in 2 (2.9%) of the 70 individuals. Thus, retrovirus seroprevalence in 1987-1988 was 22.9%. In 1987-1988, significant differences between the retroviral-positive group and the retroviral-negative group consisted of intravenous drug use greater than 16 years (P = 0.059) for an odds ratio of 3.80 (CI 1.12-12.89) and sex with female prostitutes (P = 0.029) for an odds ratio of 5.38 (CI 1.38-20.95).
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PMID:The emerging role of HTLV-I/II and HIV-1 among intravenous drug users in Detroit. 142 66

Two hundred ninety-three serum samples from Ontario hemophiliacs and 200 samples from human immunodeficiency virus-positive blood donors were screened for the presence of antibodies to human T-lymphotropic virus type I (HTLV-I) by enzyme-linked immunosorbent assay, radioimmunoassay, and Western blot techniques. None of the serum samples provided unequivocal positive results, but several samples gave inconclusive results. Of the hemophiliacs with inconclusive serologic results from whom peripheral blood lymphocyte DNA could be obtained, all were negative for HTLV-I and HTLV type II (HTLV-II) sequences as determined by polymerase chain reaction (PCR). PCR was also performed on a lymph node biopsy sample taken from a hemophiliac who developed a rare T-cell lymphoma; the sample was negative for HTLV-I and -II sequences. These results indicate that Ontario hemophiliacs have not been exposed to HTLV-I or HTLV-II.
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PMID:Absence of human T-lymphotropic virus types I and II infection in an Ontario hemophilia population. 150 3

The hemophagocytic syndrome (HPS) was first described in immune-compromised patients with secondary viral infections. Immunodeficiency has not always been diagnosed before the onset of HPS, but most patients who develop HPS have known immune deficits. HPS has also been reported in association with lymphoreticular malignancies. In HPS the most prominent histologic change is phagocytosis of red blood cells and other bone marrow-derived elements by cytologically benign histiocytes. Considerable confusion exists about the similarities and differences between HPS and other conditions in which hemophagocytosis may occur, for example, histiocytic medullary reticulosis, T-gamma lymphoma, malignant histiocytic lymphoma, and cytophagic histiocytic panniculitis. We report a patient with HPS and cutaneous lesions of cytophagic histiocytic panniculitis who also had an active Epstein-Barr virus infection, and a CD8+ T-cell lymphoma.
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PMID:Cutaneous lesions of hemophagocytic syndrome in a patient with T-cell lymphoma and active Epstein-Barr infection. 166 40

The CD4 molecule is expressed on T-helper cells and serves as the cellular receptor for the human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) and for the simian immunodeficiency viruses SIVmac and SIVagm. HIV-1, HIV-2, and SIVmac infectivity can be blocked by monoclonal antibodies (MAbs) directed against the CD4 molecule and by soluble CD4 proteins (sCD4). In the present study, we demonstrated not only lack of inhibition, but 10- to 100-fold sCD4-dependent enhancement of SIVagm infectivity of human T-cell lymphoma lines, although SIVagm infection was blocked by MAbs OKT4a and Leu3a. SIVagm enhancement with sCD4 was suppressed by MAbs OKT4a and Leu3a to levels observed without addition of sCD4. The infectivity of all four tested SIVagm variants was enhanced by sCD4 on all tested lymphoma cell lines. These results suggest a second step (second or secondary receptor) required for enhancing virus entry into the cell and may have serious implications for approaches to the treatment of acquired immunodeficiency syndrome on the basis of modified sCD4 molecules.
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PMID:Soluble CD4 enhances simian immunodeficiency virus SIVagm infection. 170 Aug 34

We report the first case (to our knowledge) of a primary urethral T-cell lymphoma as the initial manifestation of the acquired immune deficiency syndrome. A 36-year-old white homosexual man with antibodies to human immunodeficiency virus type 1 was evaluated for a hemorrhagic urethral discharge. A 2-cm fleshy, polypoid mass in the bulbous urethra was removed, and the diagnosis of small non-cleaved cell (non-Burkitt's) lymphoma was made. Immunohistochemical analysis confirmed that the tumor was of T-cell lineage. Patients with the acquired immunodeficiency syndrome have an increased incidence of lymphomas, particularly extranodal high-grade non-Hodgkin's lymphomas. Primary urethral lymphomas are extremely rare, with only a handful of cases reported in the literature. This rare form and site of lymphoma should be considered in patients with the acquired immunodeficiency syndrome who have genitourinary symptoms.
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PMID:Urethral T-cell lymphoma as the initial manifestation of the acquired immune deficiency syndrome. 174 38

S100-positive T lymphocytes account for less than 3% of peripheral blood T cells. Rare cases of S100-positive T-cell lymphoma have been previously described. We report four such cases of S100-positive T-cell chronic lymphoproliferative disease. In all cases, hepatosplenomegaly was observed, without prominent lymphadenopathy. Central nervous system (CNS) involvement by the leukemic cells was suggested in three cases by physical symptoms and confirmed in two cases by cerebrospinal fluid studies. Despite treatment, three patients died at 3, 6, and 8 months after diagnosis. Although there was a leukemic presentation, only minimal bone marrow infiltration was evident. Splenectomy showed red pulp infiltration. Liver and lymph node biopsies showed sinusoidal leukemic involvement. In all cases, the leukemic cells expressed mature T-cell- and natural killer cell-associated antigens. Cytoplasmic S100 was detected in the leukemic cells in the blood, spleen, liver, and lymph node. Southern blot studies in two cases showed T-beta, T-gamma, and T-delta gene rearrangements. RNA Northern blots showed T-alpha and T-beta chain transcripts with no T-gamma or T-delta RNA identified. Southern blot analysis showed no hybridization to probes specific for Epstein-Barr virus, cytomegalovirus, human immunodeficiency virus-1, or human T-cell lymphotropic virus type-1. These findings show that S100-positive T-cell chronic lymphoproliferative disorder is an aggressive, extramedullary-based disease frequently associated with CNS involvement and characterized by short survivals.
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PMID:S100-positive, T-cell chronic lymphoproliferative disease: an aggressive disorder of an uncommon T-cell subset. 191 67


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