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 total number of human immunodeficiency virus type 1 (HIV-1)-infected circulating CD4+ T lymphocytes is considered to be a reflection of the HIV burden at any given time during the course of HIV infection. However, the low frequency of HIV-infected circulating CD4+ T lymphocytes and the low level or absence of plasma viremia in the early stages of infection do not correlate with the progressive immune dysfunction characteristic of HIV infection. In this study, we have determined whether HIV-infected circulating CD4+ T lymphocytes are a correct reflection of the total pool of HIV-infected CD4+ T cells (i.e., HIV burden). To this end, HIV burden has been comparatively analyzed in peripheral blood and lymphoid tissues (lymph nodes, adenoids, and tonsils) from the same patients. The presence of HIV-1 DNA in mononuclear cells isolated simultaneously from peripheral blood and lymphoid tissues of the same patients was determined by polymerase chain reaction amplification. We found that the frequency of HIV-1-infected cells in unfractionated or sorted CD4+ cell populations isolated from lymphoid tissues was significantly higher (0.5-1 log10 unit) than the frequency in peripheral blood. Comparable results were obtained in five HIV seropositive patients in the early stages of disease and in one patient with AIDS. These results demonstrate that a heavy viral load does reside in the lymphoid organs, indicating that they may function as major reservoirs for HIV. In addition, the finding of a heavy viral load in the lymphoid organs of patients in the early stages of disease may explain the progressive depletion of CD4+ T lymphocytes and the immune dysfunction associated with the early stages of HIV infection.
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PMID:Lymphoid organs function as major reservoirs for human immunodeficiency virus. 168 22

HIV (human immunodeficiency virus) viraemia in serum or plasma of HIV-infected individuals was investigated by the polymerase chain reaction assay (PCR) in combination with reverse transcription to detect HIV-1 genomic RNA. Before PCR, plasma or serum was ultracentrifuged, precipitated virions were then treated with a RNase-free DNase, and a cDNA from the HIV-1 genomic RNA was synthesized. Thirty-three fresh plasma and seven sera from either HIV-1 antibody-positive individuals or patients treated with AZT were tested. Plasma from three patients were assayed 3 or 6 months apart. Twelve sera from HIV-1 antibody-negative individuals were used as negative control. PCR was performed with primers in LTR, gag and env regions: 11 of 40 samples were positive with three primer pairs, 16 with two primer pairs and 11 with only one primer pair. PCR on HIV-1 genomic cDNA was positive in 38 out of the 40 plasma or serum samples (95%), regardless of the clinical stage of the infection: HIV-1 was detected in 14 of the 15 untreated subjects and in 24 of the 25 AZT-treated patients. HIV p24 antigen was detected in the serum of 38% of subjects (15 of 40). The results suggest that this method is suitable for the detection of viral particles in plasma or serum from HIV-1-infected individuals irrespective of antiviral treatment.
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PMID:The polymerase chain reaction for the detection of HIV-1 genomic RNA in plasma from infected individuals. 171 16

An application of the polymerase chain reaction (PCR) to the direct detection of human immunodeficiency virus type 1 (HIV-1) viremia is described. The amplification of specific HIV-1 sequences of gag and env viral genes was carried out after the reverse-transcription of plasma samples (plasma RT-PCR) from seropositive subjects. The assay is faster and cheaper than detection of specific HIV-1 transcripts from peripheral blood mononuclear cells by RT-PCR. The data suggest that HIV-1 viremia is detectable by plasma RT-PCR in a large proportion of seropositive individuals.
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PMID:Detection of human immunodeficiency virus type 1 genomic RNA in plasma samples by reverse-transcription polymerase chain reaction. 171 97

Quantitative culture of human immunodeficiency virus (HIV) was performed on 121 plasma samples from 76 HIV-infected individuals to determine the sensitivity of the assay at different stages of disease and to measure the effect of antiviral therapy on plasma viremia. Plasma virus was detected in 49 of 76 (64%) of patients, primarily those with AIDS and AIDS-related complex (36 of 38) versus asymptomatic subjects (13 of 38) (p less than 0.001, chi 2). Similarly, plasma cultures were more often positive in patients with less than 250 CD4+ T cells per microliter (38 of 40) than in those with greater than 250 CD4+ T cells per microliter (11 of 36) (p less than 0.001, chi 2). Plasma virus cultures were also more likely to be positive in patients with detectable serum p24 antigen (24 of 26) than in those without detectable p24 antigen (25 of 50) (p = 0.0023, chi 2). An effect of zidovudine (ZDV) treatment on plasma viremia was seen in a comparison of treated and untreated patients with less than 250 CD4+ T cells per microliter. Geometric mean titers of plasma viremia from 16 patients treated with ZDV for more than 3 months were significantly lower than titers from 24 untreated patients (10(1.3) versus 10(2.1), p less than 0.05, Student's t test. A comparison of pre- and posttherapy titers in 33 patients receiving antiviral treatment showed that plasma virus was not detectable at either time in 17 patients; there was a fall in plasma virus titer in 12; and titers were unchanged or increased in 4. In patients with advanced disease, plasma viremia is a potential marker of antiviral drug activity.
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PMID:Plasma viremia in human immunodeficiency virus infection: relationship to stage of disease and antiviral treatment. 173 1

Acquired immune deficiency syndrome (AIDS) is caused by infection with the human immunodeficiency virus (HIV), a human retrovirus. The virus infects cells of the immune system by attachment of a glycoprotein viral envelope (gp 120) to a molecule expressed on human helper T cells called CD4. The fusion of the virus envelope protein to its specific receptor allows HIV to penetrate the T cell. Once inside the cell viral RNA is transcribed into double-stranded DNA by an enzyme unique to retroviruses, reverse transcriptase. The double-stranded, proviral DNA travels to the nucleus of the cell and is integrated into the infected cell's chromosomal DNA where it may remain latent for years. As a result of triggers that are poorly understood, viral replication becomes activated and proviral DNA is transcribed back into genomic RNA and RNA that is translated into viral proteins, both of which are packaged and bud from the infected T cell as infectious virus. The viral life cycle orchestrates the natural history of clinical HIV infection. Three to four weeks following exposure to HIV there is a phase of rapid viral replication, high levels of plasma viremia, and development of a "flue like" illness. Four to six weeks after exposure, during this stage of acute infection, antibodies to HIV core (p24) and envelope (gp 160, gp 120, gp41) proteins appear. Six to eight weeks after exposure symptoms disappear and plasma viremia subsides, presumably due to clearance by the immune system.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pathogenesis and natural history of HIV infection. 175 33

To investigate the effect of human immunodeficiency virus type 1 (HIV-1) infection on subsequent hepatitis B virus (HBV) infection, HIV antibody was sought in homosexual men who developed HBV infection during a hepatitis B vaccine trial. Among 134 unvaccinated HIV-1-negative men, 7% became HBV carriers, 64% had viremia, and 42% had clinical illness. Among vaccinated HIV-1-negative men, HBV infection severity decreased with number of vaccine doses administered. When adjusted for prior hepatitis B vaccination status, persons with HIV-1 infection preceding HBV infection had a significantly higher risk of developing HBV carriage, viremia, prolonged ALT elevation, and clinical illness. Among HIV-1-infected men, the risk of HBV carriage was increased in unvaccinated persons (21%) and those who failed to respond to vaccination (31%) and further increased in those who received vaccine doses at the time they developed new HBV infection (56%-80%), suggesting inactivated hepatitis B vaccine may temporarily impair the immune response to HBV infection in HIV-1-infected persons. HIV-1 infection was also associated with reduced alanine aminotransferase elevations during the first 36 months of follow-up of men who became HBV carriers.
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PMID:Outcome of hepatitis B virus infection in homosexual men and its relation to prior human immunodeficiency virus infection. 182 15

The status of human immunodeficiency virus type 1 (HIV-1) infection at the time of transmission to sexual contacts remains poorly defined. Transmission to nonsexual household contacts has appeared to be rare. A total of 505 sexual and nonsexual contacts of HIV-1-infected hemophiliacs in 349 households was observed. At entry, 10% of 201 sexual partners were anti-HIV-1-positive. Follow-up of 151 uninfected partners during a total of 351 person-years of observation showed no sero-conversions, although there were 13 pregnancies during that period. Eighty-seven percent of the seronegative respondents to a detailed questionnaire reported unprotected sexual contact at least occasionally. Among 304 other household members, including 108 parents who helped administer clotting factor concentrates to their children, none was seropositive at entry. Follow-up of 263 showed no seroconversions during a total of 605 person-years of observation. Thus, anti-HIV-1-positive hemophiliacs transmitted to their partners earlier in their course but were not found to do so when prospectively observed. No relationship to level of viremia as indicated by CD4 count, HIV-1 p24 antigenemia, or acquired immunodeficiency syndrome was found. Anti-HIV-1-positive hemophiliacs had not transmitted to their nonsexual household contacts before study entry and did not do so subsequently, indicating that the risk from even close nonsexual contact is extremely low.
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PMID:Risk of human immunodeficiency virus type 1 infection among sexual and nonsexual household contacts of persons with congenital clotting disorders. 186 21

A prospective multicenter study was undertaken to isolate human immunodeficiency virus type 1 (HIV-1) from 45 homosexual men for a period of 30 months after seroconversion. Efficiency of HIV-1 isolation from peripheral blood mononuclear cells was relatively stable over time, ranging from 64% at the time of seroconversion to more than 82% after 18 months of seroconversion. However, Kaplan-Meier analysis of HIV-1 culture data indicates that the cumulative proportion of HIV-1 culture positivity at 3, 6, 12, and 18 months after seroconversion was 62, 65, 84, and 92%, respectively. No significant correlation was observed between the presence of HIV-1 p24 antigen in serum, or numbers of CD4+ and CD8+ blood lymphocytes, and HIV-1 isolation within this period of time. These data suggest that HIV-1 viremia in homosexual men gradually increases to almost 100% culture positivity by 18 months after seroconversion.
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PMID:Prospective multicenter study on isolation of human immunodeficiency virus type 1 from homosexual men after seroconversion. 188 32

Human immunodeficiency virus infections complicating pregnancy have become a major public health problem worldwide. Infected women may transmit the virus to offspring and longitudinal studies have reported this risk to be from 13% to 40%. Differences in reported transmission risks are likely to be related to maternal plasma viremia, maternal immunologic responses, or both. Studies of antiretroviral therapy and immune based therapy to reduce the risk of perinatal transmission are needed. In addition to these fetal concerns, management in pregnancy needs to address maternal health-care needs and health care workers' concerns regarding the risk of occupational exposure. Appropriate maternal management includes serial assessments of maternal T-lymphocyte function and consideration of prophylactic and therapeutic treatment options proven effective in nonpregnant adults.
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PMID:Human immunodeficiency virus and the acquired immunodeficiency syndrome in obstetrics. 195 3

AZT inhibited replication of an immunodeficiency-inducing strain of feline leukemia virus (FeLV-FAIDS) in vitro at concentrations as low as 0.005 microgram/mL. This antiviral activity was augmented an additional 25-30% when AZT was combined with human recombinant alpha-interferon (2b) (IFN alpha). Administration of AZT alone or in combination with IFN alpha, beginning at the time of exposure to a 100% persistent viremia-inducing dose of FeLV-FAIDS, abrogated the progression of viral infection and protected treated animals from induction of persistent antigenemia and disease. Low levels of antigenemia were detected intermittently in some AZT-treated cats throughout the 6 week treatment and 40 week observation period. Combination of AZT with IFN alpha appeared even more effective than AZT alone. In this treatment group even transient antigenemia was undetectable throughout the therapy and posttherapy observation periods, and latent virus could not be reactivated from bone marrow cells of protected animals. These results provide additional evidence that early treatment with AZT or AZT/IFN alpha therapy can be effective in completely aborting retroviral infections.
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PMID:Therapy of presymptomatic FeLV-induced immunodeficiency syndrome with AZT in combination with alpha interferon. 196 30


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