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

Peripheral blood mononuclear cells (PBMC) and semen of 23 men infected with human immunodeficiency virus (HIV) were examined for the presence of HIV DNA and RNA using the polymerase chain reaction (PCR) and a nonisotopic detection assay. None of the men was receiving antiretroviral therapy at the time of collection. Semen samples were separated into cell-free seminal fluid, nonspermatozoal mononuclear cells (NSMC), and spermatozoa. All of the PBMC samples, 17 (74%) of 23 NSMC samples, and none of the spermatozoal samples were positive for HIV gag gene DNA. Of 23 cell-free seminal fluid samples, 15 (65%) were positive for HIV gag gene RNA by PCR. Cell-free HIV RNA was more likely to be present in the semen of men with less than 400 than in those with greater than or equal to 400 cells/mm3 (P less than .04) and was present in all patient with p24 antigen in serum. The presence of HIV DNA in NSMC samples was not related to CD4 cell count, disease status, or the presence of p24 antigen in the serum. This study shows that HIV nucleic acid can be detected by PCR in either the cell-free seminal fluid or NSMC of 87% of semen samples but not in the DNA of spermatozoa from HIV-infected men.
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PMID:Detection of human immunodeficiency virus DNA and RNA in semen by the polymerase chain reaction. 168 Jan 38

A recently recognized syndrome of acquired immunodeficiency (Acquired Immunodeficiency Syndrome-AIDS) has arisen since June 1981. It has received international attention. The clinical spectrum consists of repeated opportunistic infections, rare malignancies, and autoimmune phenomena, occurring in previously healthy adults with no history of an immunologic disorder. The population subset at risk for this syndrome appears to be predominantly homosexual American males and intravenous drug abusers with rare cases being reported in heterosexuals, hemophiliacs, and foreign patients, especially Haitians. The immunologic aberrancy in all patients described appears limited to T-lymphocyte hyporesponsiveness and imbalance of T-helper and suppressor cells. This disordered immunoregulation is a consistent finding in all reported cases and appears to predispose to the opportunistic infections and malignancies which have been associated with a 40 percent mortality. The underlying factor responsible for the immunoregulatory defect is unknown but possible etiologies include a transmissible infectious agent, drug use, chronic antigen stimulation, and spermatozoa exposure. Treatment of the associated infections and malignancies has been a frustrating endeavor as many patients respond incompletely or relapse soon after successful treatment course. Preventive measures, including patient education, physician awareness, and immunomodulating agents, are discussed.
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PMID:The Acquired Immunodeficiency Syndrome: current status. 613 99

Human cytomegalovirus (CMV) DNA was detected and quantitated in both blood and semen cells from human immunodeficiency virus (HIV)-infected men with 100-800 CD4 cell counts/mm3. None of the 35 patients studied had demonstrable CMV DNA in mononuclear cells isolated from blood. Blood samples from 8 of these patients were cultured for CMV and found to be negative. About 30% of HIV-seropositive patients in the study group had > 100 copies of CMV in semen (range, > 100 to >10(6); mean, approximately 100,000). Persistent CMV infection was detected for > 8 months in some patients with no obvious signs or symptoms of CMV disease. The CMV-infected cell in semen CD45+ and probably had Fc receptors. Mature spermatozoa were not a major reservoir of CMV infection.
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PMID:Human cytomegalovirus DNA is present in CD45+ cells in semen from human immunodeficiency virus-infected patients. 784 83

In order to investigate the role of germ cells in the sexual transmission of immunodeficiency virus (HIV), spermatozoa from healthy HIV-seronegative men were incubated in vitro with HIV1. After washing, they were cocultured with peripheral blood leukocytes from seronegative blood donors. Reverse transcriptase assays and p24 antigen tests were performed in culture supernatants. Electron microscopy examination of these HIV-incubated spermatozoa was carried out, as well as the search for CD4 molecules on their surface. Although virus bound to and seemed to enter spermatozoa despite the absence of detectable CD4 epitopes on their surface, no replication of HIV was apparent. However, HIV particles on the surface of spermatozoa were capable of infecting CD4 T lymphocytes. Present results would seem to preclude artificial insemination between an HIV-seropositive man and an HIV-seronegative woman.
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PMID:Spermatozoa as potential carriers of HIV. 814 Feb 92

Using flow cytometry, we studied the expression of the CD4 antigen within the different cells present in human ejaculate, both in spermatozoa and round cells. In all, 20 samples of semen were obtained from fertile males; in 11 of these, we detected the presence of leukocytes, using the peroxidase test. Swim-up was performed for the analysis of the spermatozoa. From our results it may be concluded that there is no expression of the CD4 antigen on the surface of human spermatozoa or on CD45- ejaculate cells (epithelial and germinal cells). However, we did detect the presence of the CD4 antigen on the surface of the leukocyte cells (CD45+). A better characterization of these CD45+ cells made it apparent that the CD4+ cells of ejaculate are composed of T lymphocytes (helper/inducer T lymphocytes) and monocytes. Thus we may conclude that human spermatozoa do not express the CD4 antigen, the cell surface receptor for human immunodeficiency virus. However, we did detect CD4+ T lymphocytes and CD4+ monocytes in semen.
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PMID:CD4+ cells in human ejaculates. 874 46

The DNA sequences of a novel human gamma-herpesvirus type 8 (HHV-8) have recently been detected in Kaposi's sarcoma (KS) lesions obtained from different populations in whom this neoplasm occurs, suggesting that this virus may be implicated in the etiology and/or pathogenesis of KS. To study the distribution and possible means of transmission of the putative viral agent, specimens of KS skin lesions, matched uninvolved skin, peripheral blood mononuclear cells (PB-MCs), and semen were collected from 12 HIV-positive homosexual men with acquired immune deficiency syndrome (AIDS)-related KS (AIDS-KS) and 2 human immunodeficiency virus (HIV)-negative homosexual men with KS. HHV-8 virus DNA was detected by polymerase chain reaction (PCR) studies in all 14 of these KS specimens and in 6 of 14 biopsies of normal-appearing skin distant from any KS lesions including 1 uninvolved skin specimen from an HIV-negative homosexual male with KS. In addition, 3 of 12 PBMC samples and 3 of 12 semen samples from the AIDS-KS patients were positive for HHV-8. The DNA sequences of HHV-8 were not detected in the matched semen and PBMC specimens obtained from 2 HIV-negative homosexual men with KS, 4 HIV-positive homosexual patients without KS, 2 HIV-seronegative healthy homosexual men, 5 HIV-positive heterosexual male intravenous drug users, or 5 healthy HIV-negative heterosexual donors. Using PCR in situ, positive signals for HHV-8 were demonstrated in the B lymphocyte subsets of PBMCs and/or in spermatozoa and mononuclear cells in the semen from some of the PCR-positive specimens from the AIDS-KS patients examined. These data show that HHV-8 is present in and could possibly be transmitted via semen and/or blood from some homosexual men with AIDS-KS.
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PMID:Detection of the herpesvirus-like DNA sequences in matched specimens of semen and blood from patients with AIDS-related Kaposi's sarcoma by polymerase chain reaction in situ hybridization. 900 31

The primary molecular changes that lead to development of acquired immunodeficiency syndrome (AIDS) are very poorly understood, as are the mechanisms underlying the protection of the developing human from the maternal immune response. Recent data that the human immunodeficiency virus (HIV) may be using the glycosylation system of the T lymphocytes to acquire glycans for its glycoproteins that enable it to disrupt carbohydrate dependent immune cell interactions or induce aberrant immune reactions. Consistent with this hypothesis, gp120 from HIV infected human H9 lymphoblastoid cells expresses biantennary N-linked glycans with a bisecting GlcNAc sequence on 11% of their total oligosaccharides. This specific carbohydrate sequence has recently been shown to protect K562 erythroleukemic cells from natural killer (NK) cell responses when presented on the cell surface. We have recently demonstrated that bisecting biantennary type N-linked glycans are also expressed on the human zona pellucida (ZP); previous lectin binding studies indicate that is also expressed on human spermatozoa. Thus both the human gametes and HIV produced by H9 cells carry this same protective carbohydrate epitope on their outer surfaces. Human alpha-fetoprotein expressed in the developing human also carries the bisecting GlcNAc sequence, indicating that it may be suppressing the emerging fetal immune response by using its carbohydrate sequence as a functional group. We have suggested that the developing human and the gametes are also protected by soluble immunosuppressive glycoproteins found in the amniotic fluid and seminal plasma known as glycodelin-A (GdA) and glycodelin-S (GdS) respectively. Structural analysis of their N-linked oligosaccharides combined with other functional studies suggest that GdA and GdS employ their very unusual carbohydrate sequences as functional groups that enable them to manifest their immunosuppressive activities. GdA and GdS are significant components of our recently proposed model for the protection of the developing human and gametes designated the human fetoembryonic defence system hypothesis. A striking relationship now emerging is that the same unusual carbohydrate sequences associated with these immunosuppressive glycodelins are also specifically expressed on intravascular helminthic parasites, Helicobacter pylori, human tumour cells, and HIV infected T lymphocytes. The information presented in this review suggests that two new corollaries should be added to our recently proposed defence system hypothesis: (i) mimicry or acquisition of glycans that are used in this protective system by pathogens or tumour cells may enable them to either subvert or misdirect the human immune response, thereby greatly increasing their pathogenicity; and (ii) expression of glycoproteins used in this system by normal cells and tissues outside the reproductive system may protect them from immune responses, especially in those cases where major histocompatibility recognition is either absent or minimal. A better understanding of this hypothesis and its corollaries may enable us to address the molecular mechanisms underlying not only AIDS but also a host of other very serious pathological conditions in the human.
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PMID:Viewing AIDS from a glycobiological perspective: potential linkages to the human fetoembryonic defence system hypothesis. 923 3

The levels of prostaglandins in human semen are many orders of magnitude higher than those found elsewhere in the body and semen contains 19-hydroxy PGE which has not been found in other tissues. The reason for the presence of these prostaglandins is now becoming apparent with the demonstration of powerful effects of PGE and 19-hydroxy PGE on the balance of cytokines (stimulating IL-10 and inhibiting IL-12) released by antigen presenting cells. The effects of the seminal prostaglandins will be two-fold. First, there will be cAMP mediated direct effect on T cells, inhibiting clonal proliferation, inhibiting natural killer cell function and biasing the CD4 cells to a T-helper-2 pattern of cytokine production away from one that would favour a cell-mediated response. Second, and perhaps the major effect, is at the level of the antigen presenting cell that will reinforce the direct effects and induce a tolerance of antigens that are presented together with the IL-10, or PGE. Such tolerance might be necessary for the survival of the spermatozoa under adverse conditions, for instance, in the presence of infection Viruses and other invading organisms would also benefit from this switch in cytokines and the inhibition of the cell-mediated defences. Particular concerns are human immunodeficiency virus (HIV) and human papilloma virus (HPV) which can be transmitted in semen. Not only will the initial immune response be affected, but also repeated exposure to semen will reduce immunesurveillance and the removal of virally infected cells.
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PMID:Prostaglandins in primate semen: biasing the immune system to benefit spermatozoa and virus? 925 Jun 93

The cellular fraction of semen contains spermatozoa, immature germ cells, leukocytes, and epithelial cells. Recent evidence implicates seminal cells as a major source of sexually transmitted human immunodeficiency virus (HIV) in semen, but the identity and infectious potential of infected cells remains poorly understood. HIV provirus was found in 75% of viable semen cell samples by polymerase chain reaction and in 88% of paired blood cell samples from HIV-seropositive men. When semen cell subpopulations were isolated by an immunomagnetic bead technique, T cells were found to be most commonly HIV-infected (75% of samples), followed by macrophages (38% of samples). Viral DNA was never detected in motile spermatozoa or immature germ cell populations. Semen leukocytes proliferated in response to mitogenic and antigenic challenge and produced p24 following stimulation with irradiated allogeneic cells. These data provide evidence that both T cells and macrophages, but not germ cells, are cellular vectors of HIV transmission in semen.
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PMID:T lymphocytes and macrophages, but not motile spermatozoa, are a significant source of human immunodeficiency virus in semen. 933 54

To select a source of lymphocytes for the generation of an anti-sperm-biased combinatorial phage display library, venous blood was obtained from 34 vasovasostomy (vasectomy reversal) patients approximately 3 mo after surgery. Using a variety of immunoassays, serum was analyzed for antibodies against human spermatozoa, and a patient was selected on the basis of high titer of antibodies that recognized the equatorial region of the sperm head and inhibited sperm fertilizing capacity in vitro. Total RNA isolated from the stored lymphocytes of this individual was reversed transcribed, and gamma1 (Fd) region and kappa chains were amplified by polymerase chain reaction for the successful construction of an antibody phage display library. The library was panned against human spermatozoa to isolate sperm-specific phage that recognized the equatorial region of the sperm head. Three preparations of Fab were tested via the hamster egg penetration test. Each preparation significantly (p < 0. 005) inhibited sperm-egg binding and fusion, with one preparation (designated Fab-G) causing complete inhibition. Sequence analysis of the kappa light gene encoding Fab-G revealed a 93% homology with the light chain of human anti-human immunodeficiency virus gp120 p35 variable region. This technology may have a practical application in characterization of the immune response to spermatozoa and for the design of sperm-based contraceptive vaccines.
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PMID:A combinatorial phage display library for the generation of specific Fab fragments recognizing human spermatozoa and inhibiting fertilizing capacity in vitro. 978 Mar 25


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