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Biomedical subjects

G Hunsmann

Publications and source records attributed to G Hunsmann.

At least 163 records · Page 9Linked to original sources
PubMed1989

Urinary neopterin concentrations in rhesus monkeys after infection with simian immunodeficiency virus (SIVmac 251).

Two rhesus monkeys were infected with SIVmac 251. Elevated urinary neopterin concentrations were observed as the first sign of infection. Virus-specific antibodies were detected 14 days after infection, when neopterin concentrations were already decreasing. The neopterin levels of one animal remained elevated and the virus was repeatedly isolated. Urinary or serum neopterin concentrations appear to be early markers for SIV infection and viremia in rhesus monkeys.

Animals↗
PubMed1989

In vitro anti-HIV-1 activity of chondroitin polysulphate.

Three chondroitin sulphates and five chondroitin polysulphates, with molecular weights ranging from 3000 to 30,000 daltons, were evaluated applying the MT-4 cell-culture assay for inhibition of HIV-1 replication. These results were compared with those obtained with compounds of known in vitro antiretroviral activity, namely, dermatan sulphate, heparin, dextran sulphate, pentosan polysulphate, zidovudine (AZT) and suramin. Chondroitin polysulphate with a molecular weight (MW) of 9000 daltons (CPS 9000) was the most effective polyanionic compound studied. In contrast with zidovudine, this CPS 9000 was not toxic for MT-4 cells up to a concentration of 500 micrograms/ml. Moreover, CPS 9000 is highly specific for inhibition of HIV-1 reverse transcriptase.

Cells, Cultured↗
PubMed1989

Structural variability of the external glycoprotein of simian immunodeficiency virus propagated in cell cultures.

We examined the structural variability of the external glycoprotein (gp130) of a cloned simian immunodeficiency virus (SIV) in culture. Cloned SIVmac142 was either permanently propagated in HUT-78 cells or sequentially passaged in MT-2 cells. After 12, 24 and 60 passages of permanent or lytic cell-culture systems, virus was harvested, gp130 was isolated and peptide mapped. Comparison of gp130 peptide maps of SIVmac142 by computer graphic analysis revealed a variation in relative spot intensity of up to 20%. No major variability of gp130 was observed in SIVmac142 propagated in HUT-78 cells (i.e. without cytopathic effect induction) in up to 60 passages. However, in MT-2 cells, which are lysed by this virus, gp130 exhibited significant variability and displayed six additional fragments in peptide maps after 24 passages. Peptide map of SIVmac142 gp130 obtained after 60 passages in MT-2 cells was comparable to that after 24 passages. Alterations in the intensity of certain spots indicated changes in the composition of the replicating virus population.

Genetic Variation↗
PubMed1988

Carbohydrates of human immunodeficiency virus. Structures of oligosaccharides linked to the envelope glycoprotein 120.

Human T-cells (H9), persistently infected with the HTLV-III strain of human immunodeficiency virus, were metabolically labeled with D-[2-3H]mannose or D-[6-3H]glucosamine. The viral envelope glycoprotein, gp120, was isolated either from cell lysates or from cell-free culture supernatant. After proteolytic digestion, the radiolabeled oligosaccharides were sequentially liberated from glycopeptides by treatment with endo-beta-N-acetylhexosaminidase H and peptide:N-glycosidase F. Oligosaccharides released were separated from residual (glyco)peptides and fractionated according to size, charge, and fucose content. The individual oligosaccharide species obtained were characterized by digestion with exoglycosidases and by chromatographic comparison with standard oligosaccharides. Our results demonstrate that the intracellular gp120 carries predominantly oligomannosidic glycans comprising nine or eight mannose residues. The secreted glycoprotein is equally substituted by oligomannosidic species, containing seven to nine mannose residues, and by fucosylated, partially sialylated bi- and triantennary complex-type oligosaccharides.

Carbohydrate Conformation↗
PubMed1988

Enhanced in vitro inhibition of HIV-1 replication by 3'-fluoro-3'-deoxythymidine compared to several other nucleoside analogs.

Nucleoside analogs were synthesized and tested for anti-HIV-1 activity in two in vitro test systems using MT-4 cells and peripheral blood lymphocytes. Cytotoxicity was assessed in both assays and additionally in several human lymphoblastoid cell lines. One analog, 3'-fluoro-3'-deoxythymidine, exhibited higher antiviral potency and slightly higher cytotoxicity than 3'-azido-3'-deoxythymidine. Analogs showing lower cytotoxicity than 3'-azido-3'-deoxythymidine demonstrated reduced antiviral activity. 3'-fluoro-3'-deoxythymidine may become an alternative chemotherapeutic agent because of its high antiretroviral potency. Its toxicity, however, deserves further investigation.

Cell Line↗
PubMed1988

Antibodies to human immunodeficiency virus (HTLV-III/LAV) in people from Lagos and Cross River States of Nigeria.

Using enzyme-linked immunosorbent assay (ELISA) and confirmatory immunoprecipitation tests, sera from 640 Nigerians from Lagos and Cross River States were examined for antibodies against HIV. These comprised 570 blood donors and their family members, 56 patients with various haematological conditions and 14 patients with acute Plasmodium falciparum infection. None of the sera was positive for HTLV-III/LAV antibodies by immunoprecipitation, although 12 (1.9%) sera were positive by ELISA.

Acquired Immunodeficiency Syndrome↗
PubMed1987

A new ELISA test for HIV antibodies using a bacterially produced viral env gene product.

Screening tests for antibodies to the human immunodeficiency virus (HIV), based on the indirect ELISA principle using viral preparations as antigen, yield a substantial number of false-positive and false-negative results. These failures are due to the lack of certain viral polypeptides or contaminating cellular polypeptides in viral preparations. Therefore, the accuracy of the screening tests should be improved by using highly purified, synthetic viral antigens. With establishment of such an ELISA antigen in mind, we examined a bacterially synthesized polypeptide [ENV(80)] that corresponds to 80 conserved amino acids of the HIV gp41 transmembrane glycoprotein. ENV(80) was expressed as a DHFR fusion protein in Escherichia coli. Results obtained by HIV ELISA and immunoprecipitation with 497 serum samples from various groups at risk of AIDS were compared with those obtained with the ENV(80) ELISA. The ENV(80) ELISA was found to be superior to the H9/HTLV-III ELISA with respect to sensitivity and specificity and is almost equivalent in accuracy to immunoprecipitation.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Efficient replication of HTLV-III and STLV-IIImac in human Jurkat cells.

High producer cell lines were established by infecting Jurkat cells with either HTLV-IIIB from H9 cells or with STLV-IIImac from HUT-78 cells. The Jurkat cells produced both viruses at least 10 times more efficiently then the original cell lines; the pelleted virus from Jurkat cells was also less contaminated with non-virion proteins. Accordingly, a higher specificity was attained in an ELISA for antibodies to HTLV-III if the antigenic activity was derived from the virus from Jurkat cells, as opposed to that from H9 cells.

Acquired Immunodeficiency Syndrome↗
PubMed1987

Multiple sclerosis and human T-cell lymphotropic retroviruses: negative serological results in 135 German patients.

A total of 135 sera and 18 cerebrospinal fluid (CSF) samples from patients with multiple sclerosis (MS) were screened for antibodies to human T-cell lymphotropic virus type I (HTLV-I) and human immunodeficiency virus (HIV) by ELISA tests. None of the sera or CSF reacted with HIV antigens. Only 3 out of 135 MS sera but no MS CSF showed increased reactions in the ELISA test for HTLV-I. However, these positive reactions were classified as non-specific by immunoprecipitation. Thus no serological evidence for infection with HIV, HTLV-I, or a related retrovirus was found in the MS patients.

Antibodies, Viral↗
PubMed1987

Neutralizing antibodies and the course of HIV-induced disease.

The capacity to neutralize the human immunodeficiency virus (HIV) in vitro was examined in 52 sera obtained from 23 seropositive individuals in addition to 7 negative control sera. Neutralization was measured as the activity of a serum to protect MT-4 cells against the cytopathic effect of HTLV-IIIB. Virus neutralization depended on HIV antibodies. Some sera had HIV neutralizing antibody titers of several thousands. All serum samples had been titrated in two ELISAs based either on disrupted HTLV-IIIB or on a bacterially synthesized polypeptide (ENV-80) of gp41 as a test antigen. The correlation of neutralizing activity of the sera with ELISA titers was low. A correlation of serum neutralizing titers with the stage of the disease could not be observed. However, in a longitudinal study with 6 patients over up to 22 months an increase in neutralizing antibodies seemed to protect against progression of the disease. The implications of these findings for antibody treatment and vaccine development are discussed.

AIDS-Related Complex↗