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)

The prevalence of IgG antibodies to human B19 parvovirus (anti-B19) is elevated in individuals infected with human immunodeficiency virus (HIV), especially during the later stages of HIV infection. In subjects with high titers of IgG anti-B19, 86% (19 of 22) had circulating B cells producing anti-B19. Immortalization of these cells with Epstein-Barr virus and generation of heterohybridomas by fusion with a mouse X human heteromyeloma resulted in the production of two cell lines producing IgG1 kappa monoclonal antibodies (MAbs). Both of these MAbs were specific for conformational epitopes on the VP2 capsid protein of B19 parvovirus and both were capable of neutralizing 50% of the viral infectivity in a human erythroid colony-forming unit assay at < or = 1 micrograms of MAb/mL. These human MAbs are potentially useful in the treatment of acute B19 parvovirus infection.
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PMID:Generation of neutralizing anti-B19 parvovirus human monoclonal antibodies from patients infected with human immunodeficiency virus. 835 99

Persistent parvovirus B19 infections in human immunodeficiency virus type 1 (HIV-1)-infected patients have been reported. The two viruses could share common target cells. The NS1 protein of B19 regulates B19 expression and we have investigated its possible effect on the long terminal repeat (LTR) of HIV-1. In transient transfection experiments, NS1 trans-activated the expression of reporter genes under the control of the HIV-1 LTR. The effect of NS1 was apparent only in the presence of the HIV-1 Tat protein, and required intact TAR and TATA box sequences.
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PMID:Trans-activation of the long terminal repeat of human immunodeficiency virus type 1 by the parvovirus B19 NS1 gene product. 837 75

Information concerning the most recently discovered infections with perinatal implications is constantly expanding. Hepatitis C virus is responsible for the majority of cases of sporadic and transfusion-related non-A, non-B hepatitis. Its prevalence in the general obstetric population is approximately 2%, but it is much higher in intravenous drug users and recipients of blood transfusions. The risk of vertical transmission is probably small (approximately 4.5%), but mothers coinfected with hepatitis C virus and human immunodeficiency virus type 1 are at higher risk of transmitting infection, possibly as a result of higher levels of viremia. Parvovirus B19 infection can jeopardize the fetus in approximately 9% of cases, leading to profound anemia, followed by hydrops and death. B19 has not been proven to be teratogenic, but survivors have a greater risk of in utero growth retardation. Cytomegalovirus remains the most common cause of congenital infections, and the fetal effects of primary maternal infection during gestation can be devastating. Recurrent infections carry a much lower risk of vertical transmission. Prenatal diagnosis is feasible and reliable. The factors affecting the vertical transmission of human immunodeficiency virus type 1 have been further delineated, and new avenues of research have been opened.
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PMID:Perinatal infections. 838 Oct 35

Persistent B19 parvovirus infection has been recognized in immunocompromised patients, often occurring with a low-titer viremia. In this study, nested polymerase chain reaction (PCR) for the detection of B19 parvovirus DNA was carried out on the sera of 49 human immunodeficiency virus (HIV)-1-seropositive patients, negative for the detection of B19 DNA at dot blot hybridization assay and with different values of serum anti-B19 IgM (27 patients proved positive and 22 negative). Of the 49 HIV-seropositive samples tested by nested PCR, seven were positive for the detection of B19 DNA. All seven belonged to the group of subjects seropositive for specific anti-B19 IgM. The study shows that, in the presence of specific B19 IgM, circulating virus may still be present but can be detected only by PCR. In that B19 infection can occur with low-titer viremia in immunocompromised patients, PCR may be the only method for virus detection.
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PMID:Nested polymerase chain reaction assay for the detection of B19 parvovirus DNA in human immunodeficiency virus patients. 839 55

Parvovirus B19 infection may cause chronic anemia in human immunodeficiency virus (HIV)-infected hosts. Small-scale studies and case reports have suggested that parvovirus B19 infection is a significant cause of anemia in HIV-infected patients. We studied single serum samples from 317 consecutive HIV-infected patients with use of parvovirus B19-specific serology and polymerase chain reaction for detection of viral DNA. Anemia was noted in 176 patients (55.5%); 126 (39.9%) had < 0.10 x 10(9) CD4+ cells/L. In this study group, 191 (60.3%) of the patients were positive for parvovirus B19 IgG. Seroprevalence rates did not differ between patients with low and higher CD4+ cell counts or between anemic and nonanemic patients. Parvovirus B19 DNA was detected in none of the sera. In a control group of 226 healthy male blood donors, the seroprevalence of parvovirus B19 IgG was 68.1%; two IgG-positive sera also contained parvovirus B19 DNA. This study demonstrates that chronic parvovirus B19 infection should not be considered a frequent cause of anemia in HIV-infected individuals.
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PMID:Prevalence of parvovirus B19 infection in patients infected with human immunodeficiency virus. 895 68

Due to the preparative regimen necessary, bone marrow transplantation (BMT) consistently results in severe immunodeficiency, often associated with anaemia, leukopenia and thrombocytopenia. Parvovirus B19 replicates in red blood cell precursors in the bone marrow and causes erythema infectiosum ('fifth disease'), anaemia, arthritis and foetal death. We assessed the significance of B19 infections as a cause of post-BMT complications. Over 900 serial serum samples from 201 allogeneic bone marrow recipients were studied by polymerase chain reaction (PCR) and by modern serodiagnostic methods. During the first 6 months after transplantation all BMT recipients remained B19 PCR-negative. Antibody screening for B19 infections was performed up to 36 months post-transplantation. Three cases of acute B19 infection were diagnosed during the second year post-BMT. To characterize the adoptively transferred immune system we measured subclasses and avidity of anti-VP1 IgG and epitope-type specificity (ETS) of anti-VP2 IgG, which allowed functional differentiation of primary and secondary B-cell responses long after BMT. The profile of the immune response was that of a primary infection in 1 and of reinfection in 2 of the 3 acute cases. Both types were clinically mild. Infection by human parvovirus B19 is not a frequent cause of post-BMT cytopenias. The findings with the new B19 antibody markers support the concept that the donated marrow determines the type of antiviral B-cell responses.
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PMID:Primary and secondary infections by human parvovirus B19 following bone marrow transplantation: characterization by PCR and B-cell molecular immunology. 918 47

Parvovirus B19 (B19) DNA was detected by dot blot hybridization in sera from 5 (17%) of 30 human immunodeficiency virus (HIV)-infected patients with hematocrits (HCT) of < or =24 and 4 (31%) of 13 HRV-infected patients with HCT of < or =20, suggesting that B19 is a reasonably common cause of severe anemia in HIV infection. The anemia promptly remitted after immunoglobulin therapy in 3 of 4 treated patients. The presence of IgM to B19, the clinical circumstance in which anemia developed, and the marrow morphology were poor predictors of chronic B19 infection. DNA hybridization studies of sera from 191 HIV-infected and 117 HIV-seronegative homosexual males attending a clinic in the Seattle area revealed that 1 (0.5%) and 2 (2%) samples, respectively, from the 2 groups contained B19. However, when assayed by polymerase chain reaction (PCR), 5% of the serum samples from HIV-infected persons and 9% from uninfected persons contained B19, although each had an HCT of > or =40. The data argue that anemia results from chronic high-titer B19 infection. Although a negative PCR assay excludes this diagnosis, DNA hybridization may be the more specific serum test.
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PMID:Clinical relevance of parvovirus B19 as a cause of anemia in patients with human immunodeficiency virus infection. 960 72

Human parvovirus B19, which infects and lyses erythroid precursors, can cause severe anemia in patients with immunodeficiency. The incidence of parvovirus infection in adult acquired immunodeficiency syndrome (AIDS) patients is unknown. Eighty-one archival formalin-fixed, paraffin-embedded (FFPE) bone marrow biopsies from 73 AIDS adults were immunostained with monoclonal R92F6 against B19 VP1 and VP2 capsid proteins using streptavidin peroxidase and streptavidin alkaline phosphatase techniques. In addition, the same tissues were hybridized in situ with a digoxigenin-labeled parvovirus B19 DNA probe. Five FFPE bone marrows, from 3 HIV-negative patients with positive immunoglobulin M (IgM) serology for parvovirus B19, and 1 parvovirus B19-infected fetal liver were positive controls. By immunoperoxidase, all tissues were negative with R92F6 except the fetal liver, which exhibited strong positivity predominantly in viral inclusions. With immunoalkaline phosphatase, all positive controls were immunoreactive with R92F6; however, the AIDS marrows were negative. With in situ hybridization (ISH), all positive controls and 7 of 81 (8.6%) of AIDS marrows were positive for B19 parvovirus DNA. We conclude that ISH is more sensitive than R92F6 immunohistochemistry in parvovirus B19 detection. A small but significant number of bone marrows from AIDS adults shows evidence of human parvovirus B19 infection.
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PMID:Human parvovirus B19 in bone marrows from adults with acquired immunodeficiency syndrome: a comparative study using in situ hybridization and immunohistochemistry. 922 41

To detect and characterize parvovirus B19 infection during the course of progressive immune deficiency from human immunodeficiency virus (HIV), ten subjects enrolled in the Multicenter Hemophilia Cohort Study were followed for 6.4 to 15 years from HIV seroconversion through extreme immune deficiency. Four to five sera or plasma samples from each subject, collected at predetermined CD4+ lymphocyte levels, were tested for immunoglobulin G (IgG) and M (IgM) B19 antibodies and DNA. All 42 samples were positive for B19 IgG antibodies, and three were weakly positive for IgM antibodies. Only one sample, collected coincident with HIV seroconversion, was unequivocally positive for B19 DNA. No persistent hematologic adverse effects of B19 infection were observed. Thus, although B19 IgG antibodies are highly prevalent among HIV-infected persons with hemophilia or related disorders, B19 viremia and its hematologic consequences were not detected, even with severe depletion of CD4+ lymphocytes. If primary B19 infection occurs after immune deficiency, however, the consequences may be more adverse.
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PMID:Parvovirus B19 quiescence during the course of human immunodeficiency virus infection in persons with hemophilia. 939 87

In a prospective study to determine the prevalence of parvovirus B19 in adult patients positive for the human immunodeficiency virus, a series of 55 consecutively presenting patients was tested for antibodies to parvovirus B19 and parvovirus B19 DNA. Specific IgG antibodies were detected in 96% of cases; specific IgM antibodies were present in 10%. Viral DNA was not detected in any of the sera analysed by polymerase chain reaction. Anemia could not be correlated with the presence of either IgG or IgM antibodies to parvovirus B19. Thus, no evidence of acute or chronic parvovirus B19 infection was found in the 55 patients. These findings suggest that active parvovirus B19 infection is uncommon in HIV-infected patients.
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PMID:Low prevalence of active parvovirus B19 infection in HIV-infected patients. 940 50


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