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J C Chermann

Publications and source records attributed to J C Chermann.

At least 145 records · Page 8Linked to original sources
PubMed1984

Induction of cellular DNA polymerases in a Burkitt lymphoma-derived cell line by treatment with 5-iododeoxyuridine.

Cellular DNA polymerases of a Burkitt lymphoma-derived cell line (P3HR-1) were found to be greatly induced by treatment of the cells with 5-iododeoxyuridine (IUdR) at a concentration which induces Epstein-Barr virus (EBV) early antigen (EA) expression. The activities of all the DNA Polymerases alpha, beta and gamma in P3HR-1 cells increased 7-9 fold by exposure of the cells to IUdR (25 micrograms/ml) for 3 days, while the EBV-coded DNA polymerase activity in the cell remained undetectable under the assay conditions employed. Under the same culture conditions with IUdR, EA-positive P3HR-1 cells increased to 16.6% which was much higher than that of the non-treated control cells (0.32%). On the other hand, another Burkitt lymphoma cell line, Raji, had very low incidence (1.27%) of EA induction by IUdR-treatment and the level of DNA polymerase activities remained almost unchanged. From these results it seems that the increase in DNA polymerase activity during the treatment of P3HR-1 cells with IUdR is closely related to high incidence of EA expression in these Burkitt lymphoma cells. Also, the finding has revealed yet unknown effect of IUdR on cultured cells and provides a useful tool to obtain a large quantity of the induced cellular DNA polymerases from the P3HR-1 and KB cells.

Burkitt Lymphoma↗
PubMed1984

Antibodies to the core protein of lymphadenopathy-associated virus (LAV) in patients with AIDS.

Lymphadenopathy-associated virus ( LAV ), a human T- lymphotrophic retrovirus isolated from a homosexual man with lymphadenopathy, has been causally associated with acquired immunodeficiency syndrome (AIDS). A sensitive and specific radioimmunoprecipitation test was developed for the detection of antibodies to the major core protein of LAV , p25 (molecular weight 25,000). Antibody to LAV p25 was found in the serum of 51 of 125 AIDS patients, 81 of 113 patients with lymphadenopathy syndrome, 0 of 70 workers at the Centers for Disease Control (some of whom had handled specimens from AIDS patients), and 0 of 189 random blood donors. Of a group of 100 homosexual men from San Francisco whose serum was obtained in 1978, only one had antibody to LAV p25; in contrast, of a group of 50 homosexual men in the same community whose serum was obtained in 1984, 12 had antibodies to LAV p25.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Selective tropism of lymphadenopathy associated virus (LAV) for helper-inducer T lymphocytes.

Lymphadenopathy associated virus ( LAV ) has been isolated from patients with the acquired immunodeficiency syndrome (AIDS) or lymphadenopathy syndrome. Since the immune deficiency in AIDS seems to be primarily related to the defect of the helper-inducer T lymphocyte subset, the possibility that LAV is selectively tropic for this subset was investigated. Fractionation of T lymphocytes was achieved by cellular affinity chromatography with monoclonal antibodies. In a hemophilic patient who was a healthy carrier of LAV , reverse transcriptase activity and virus particles detected by electron microscopy were found only in cultures of helper-inducer lymphocytes. When infected with LAV in vitro, lymphocyte subsets from normal individuals yielded similar results. Virus production was associated with impaired proliferation, modulation of T3-T4 cell markers, and the appearance of cytopathic effects. The results provide evidence for the involvement of LAV in AIDS.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Adaptation of lymphadenopathy associated virus (LAV) to replication in EBV-transformed B lymphoblastoid cell lines.

A strain of lymphadenopathy associated retrovirus ( LAV ) passaged in vitro was used to infect a lymphoblastoid cell line obtained by transformation with Epstein-Barr virus of B lymphocytes from a healthy donor. The virus produced from this line (B- LAV ) was also able to grow at a high rate in some other lymphoblastoid lines and in a Burkitt lymphoma line. This adapted strain retained the biochemical, ultrastructural, and antigenic characteristics of the original strain, as well as its tropism for normal T4+ lymphocytes. It is thus possible to grow LAV in large quantities that can be used for the preparation of diagnostic reagents. The interaction between such a human retrovirus and Epstein-Barr virus, a DNA virus, may have some implication for the pathology of the acquired immunodeficiency syndrome and related diseases.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Lymphadenopathy associated virus infection of a blood donor--recipient pair with acquired immunodeficiency syndrome.

A retrovirus isolated from three patients with the acquired immunodeficiency syndrome (AIDS) in the United States was morphologically and antigenically identical to lymphadenopathy associated virus isolated in France. Two of these isolates were from a blood donor-recipient pair, each of whom developed AIDS. Lymphadenopathy associated virus was isolated from the blood donor's lymphocytes 12 months after his onset of AIDS symptoms and from the blood recipient's lymphocytes 1 month after her onset of AIDS symptoms. Two isolates from the blood donor-recipient pair and an isolate from an epidemiologically unrelated homosexual man were examined by competitive radioimmunoassay to determine their antigenic relatedness to each other and to other human retroviruses. The major core proteins (p25) of the isolates were antigenically identical and all three isolates were identical to prototype lymphadenopathy associated virus isolated in France.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Characterization of the RNA dependent DNA polymerase of a new human T-lymphotropic retrovirus (lymphadenopathy associated virus).

We described here the characteristics of the Reverse Transcriptase activity associated with the Lymphadenopathy Associated Virus ( LAV ). A critical concentration of non ionic detergent, all four deoxyribonucleosides triphosphates and the divalent cation Mg2+ are required for optimal endogenous enzyme activity. The endogenous reaction product is digested by DNase and not by RNase and its synthesis is only slightly inhibited by actinomycin D. Exogenous reactions are optimal using poly A oligo dT12 -18 or poly Cm oligo dG12 -18 as template primer and Mg2+ as divalent cation. This enzyme can be distinguished from other cellular DNA polymerases activities and from Terminal deoxynucleotidyl Transferase (TdT) by purification from LAV infected T lymphocytes using phosphocellulose column.

Chemical Phenomena↗
PubMed1984

Isolation of new lymphotropic retrovirus from two siblings with haemophilia B, one with AIDS.

A human T-lymphotropic retrovirus was isolated from cultured T lymphocytes from two siblings with haemophilia B. Patient 2 was healthy, but patient 1 had acquired immunodeficiency syndrome. The retrovirus differed from human T-cell leukaemia virus (HTLV) but it was similar to the lymphadenopathy-associated retrovirus (LAV) in its morphology and its major core protein (P25). Both patients had antibodies against LAV and patient 1's retrovirus, detected by an enzyme-linked immunosorbent assay or a radioimmunoprecipitation assay. Seroepidemiological data indicated the transmission of this retrovirus by plasma products.

Acquired Immunodeficiency Syndrome↗
PubMed1984

Sequences related to mouse mammary tumor virus genome in tumor cells and lymphocytes from patients with breast cancer.

Cloned murine mammary tumor virus (MuMTV) sequences allowed us to search for murine mammary tumor virus related sequences in the DNA of surgically removed human breast tumors. Out of 28 tumors so far examined two were found to contain an Eco RI DNA fragment homologous to the long terminal repeat-group antigen (LTR-Gag) and the Envelope (Env) sequences of MuMTV. We have taken the lymphocytes of these patients and cultured them. Rapid growth of lymphocytes, mostly of T origin, occurred in the presence of T cell growth factor (TCGF). Whereas DNA extracted from fresh lymphocytes is negative, that extracted from the 3-day cultured lymphocytes showed MuMTV related sequences. Long term cultures of T cells and a similar culture derived from a healthy person donor were negative at all stages. DNA extracted from the Ebstein Barr Virus-transformed B cells of the patient does not contain the MuMTV related sequences.

Breast Neoplasms↗
PubMed1984

Modulation by the polyoxotungstate HPA-23 of Epstein-Barr virus early antigen expression in Raji cells treated with iododeoxyuridine.

The polyoxotungstate HPA-23 was found to exert a differential effect on the induction of Epstein-Barr virus early antigen in Raji cells induced with 5-iodo-2'-deoxyuridine (IUdR). Thus, treatment of Raji cells concomitantly with IUdR and HPA-23 inhibited early antigen expression, and the extent of inhibition was proportional to the duration of treatment with HPA-23. In contrast, pretreatment of Raji cells with HPA-23 prior to induction with IUdR stimulated early antigen expression in exponentially multiplying but not in stationary-phase cells. HPA-23 alone had no effect on early antigen expression in Raji cells. Activation of the latent Epstein-Barr virus genome by IUdR is dependent upon incorporation of the thymidine analogue into cellular DNA during the S-phase of the cell cycle. Synthesis of Epstein-Barr virus DNA also takes place during S-phase, suggesting a possible participation in this process of cellular DNA polymerase alpha which is thought to be responsible for cellular DNA replication and the activity of which increases several-fold during S-phase. Treatment of Raji cells with HPA-23 caused a marked decrease in DNA polymerase alpha activity, which could result in an inhibition of IUdR incorporation leading to the observed reduction of early antigen expression in cells treated concomitantly with IUdR and HPA-23.

Antigens, Viral↗
PubMed1984

Inhibition of DNA polymerase alpha activity by ammonium 21-tungsto-9-antimoniate (HPA23).

Ammonium 21-tungsto-9-antimoniate (HPA23), an inorganic condensed ion, was shown to be a potent inhibitor for DNA polymerase alpha but not for beta. It inhibited the activity of mammalian DNA polymerase alpha in noncompetitive fashion with respect to either of deoxynucleotide substrate and template X primer, indicating the presence of a specific binding site for HPA23 on DNA polymerase alpha molecule. The Ki of the alpha polymerase for HPA23 was 24 nM. A possible interaction of HPA23 with DNA polymerase alpha is discussed.

Animals↗
PubMed1984

Lymphadenopathy associated virus and its etiological role in AIDS.

Lymphadenopathy associated virus (LAV) is a novel human retrovirus first reported in 1983. It was isolated from the lymph node lymphocytes of a French homosexual patient with generalized hyperplasic lymphadenopathy. Subsequently LAV was isolated from patients with frank acquired immune deficiency syndrome (AIDS) coming from all the different high-risk groups, while anti-LAV antibodies were detected equally in individuals from all "at-risk" groups. Such a profile is consistent with the virus being the major etiological agent of AIDS. Furthermore its biological properties, namely its cytopathic effect in vitro, its T4-cell tropism as well as the role of the T4 molecule in virus infection explain, at least in part, the pathophysiology of AIDS. The major core (gag) proteins are p18, p25, and p13 which are products of a Pr55 precursor. The major envelope (env) glycoprotein is unusually large (gp110) for a retrovirus and comparable to those of the lentiviruses. Recently the virus has been molecularly cloned. The genome is 9.2 kb long, longer than any other known replication competent retrovirus apart from the lentiviruses. The absence of molecular hybridization between cloned LAV and human T-cell leukemia/lymphoma virus (HTLV) genomes compounds the original and extensive differences noted between these viruses and demonstrates that LAV is a prototype of a new class of human retrovirus.

Acquired Immunodeficiency Syndrome↗