Biomedical subjects

J Peries

Publications and source records attributed to J Peries.

At least 19 recordsLinked to original sources

PubMed1997

Mycosis fungoides and Sezary syndrome are not associated with HTLV-I infection: an international study.

Association between mycosis fungoides (MF), its leukaemic variant Sezary syndrome (SS) and the human T-cell lymphotropic virus type-I (HTLV-I) has been controversial, with the reported incidence of infection varying between 0% and nearly 100%. We studied 127 patients (85 MF, 28 SS, five Sezary cell leukaemia, four lymphomatoid papulosis, and five unspecified cutaneous T-cell lymphomas (CTCL)) originating from Europe (France, Spain, U.K., Portugal) or from U.S.A. (California) for the presence of HTLV-I infection markers. HTLV-I and -II serology were performed on 78 patients using standard immunological methods. Reverse transcriptase (RT) assay was also performed in 26 cases using an RT-PCR-based method of high sensitivity. Molecular analyses were performed on 215 DNA samples (121 from fresh PBMCs, 26 from PBMCs after short-term culture and 68 from skin lesions) by PCR amplification using HTLV-I and -II gag, pol, env, pX and LTR specific primers. Immunological tests were negative except for two sera which were indeterminate. PCR with all HTLV-I and -II primer pairs showed negative results in all 215 samples investigated. No RT activity was detected in short-term PBMC cultures of any of the 26 cases studied. The results of this large study from five different countries clearly indicate that MF and SS are not associated with HTLV-I infection.

Blotting, Western↗

PubMed1996

Inhibition of the in vitro infectivity and cytopathic effect of human foamy virus by dideoxynucleosides.

Human foamy virus (HFV) is a human retrovirus that has not been clearly associated with human disease. In this study, we tested the capacity of nucleoside derivatives to inhibit the infectivity and cytopathic effect of HFV in T-lymphoblastoid cells in vitro. H9 cells showed a dramatic cytopathic effect 3 weeks after exposure to HFV. At this time, viral infection was demonstrated by detection of viral antigens by immunofluorescence staining, release of reverse transcriptase activity (RT) in the supernatant, detection of typical viral particles by electron microscopy, and presence of proviral DNA by Southern blot analysis. H9 cells were pretreated with dideoxycytidine (ddC), dideoxyinosine (ddI), or azidothymidine (AZT) at various concentrations before HFV infection. ddC could not completely suppress viral replication at low concentrations, and inhibited cell proliferation at higher concentrations. ddI partially inhibited the formation of giant cells at 10 microM, with 95% inhibition of RT in the supernatant. AZT induced a complete inhibition of cytopathic effect at concentrations > or = 1 microM, with more than 95% inhibition of RT in the supernatant. Moreover, the synthesis of proviral DNA was completely suppressed by 10 microM AZT. These results show that AZT and ddI can inhibit HFV replication in vitro.

Blotting, Southern↗

PubMed1995

Human T-cell-leukemia virus type I in post-transfusional spastic paraparesis: complete proviral sequence from uncultured blood cells.

Human T-cell-leukemia virus type I (HTLV-I) is the causative agent of adult T-cell leukemia/lymphoma (ATL) and tropical spastic paraparesis/HTLV-I-associated myelopathy (TSP/HAM). The different disease outcome may be attributable to subtle mutations leading to modification of viral tropism or infectivity. Initial attempts found a very high level of sequence conservation among all HTLV-I strains. However, only one complete proviral DNA sequence is reported from a TSP/HAM patient, with a provirus derived from immortalized lymphocytes, which might be expected to be a leukemogenic variant rather than a neurotropic one. We cloned and sequenced a complete HTLV-I provirus (HTLV-IBoi) derived from the uncultured lymphocytes of a sub-acute post-transfusional TSP/HAM patient with clonal integration of HTLV-I. HTLV-IBoi proviral genome is 9033 bp long, and its overall genetic organization is similar to that of the prototype HTLV-I(ATK), without major deletions or insertions. No premature termination codon was found in the 4 open reading frames of the pX region. Divergence at the nucleotide level of HTLV-IBoi from the reported full-length HTLV-I varies from 1 to 9.4%, and indicates that it corresponds to a cosmopolitan genotype. This study did not identify specific sequences associated with neurotropic strains.

Adult↗

PubMed1995

Biological and molecular studies on Syrian hamster intracisternal R-type particles.

Retrovirus-like intracisternal R-type particles (IRP) are structures present in Syrian hamster (Mesocricetus auratus) cells cultured in vitro where they appear either spontaneously or under chemical induction conditions. We have tested several chemical inducers and ten different cell lines, looking for the best IRP induction conditions. BHK21 cl. 13 showed the highest inducibility one day after a 24 h treatment with 1 microgram/ml of 5-aza-2'-deoxycytidine. Using detergent treatments and sucrose gradients, we obtained semi-purified IRP cores. A 7.2 kb RNA associated with the core fraction was revealed by hybridization with total Syrian hamster genomic DNA, but not with Syrian hamster intracisternal A particle (IAP) specific probes. This suggests that the IRP genes are distinct from IAP ones.

Animals↗

PubMed1995

Human foamy virus DNA forms and expression in persistently infected Dami megakaryocytic cells.

We have characterized human foamy virus (HFV) proviral DNA and determined HFV expression in a persistent infection model, the Dami megakaryocytic cell line. Molecular studies were performed on parental persistently infected cells (Dami-P), as well as on derived clones (Dami-Cl). We report that in these nonlytic and non-HFV producer cells, viral DNA was found to be integrated into the cellular genome and that the few free proviral forms detected in Dami-P cells were deleted in their 5' LTR. Our molecular analysis indicates the presence of undeleted 5' LTR forms in the integrated provirus within a proviral population mainly composed of deleted forms. In addition, the deletion in the bel1 trans-activator gene, previously described by Saïb et al., was found to be highly predominant. However, in 5-iodo-2'-deoxyuridine treated Dami-Cl cultures, virus production occurred, providing evidence for the presence of complete viral genome. Analysis of HFV expression in Dami-Cl cells, by Northern blot and immunoprecipitation, shows that the most striking difference between cytolytic and persistent HFV infection was the lack of expression of structural viral proteins, in contrast with Bet protein expression, which is maintained. Our data suggest that the Bet protein could be involved in the maintenance of viral persistency and that the persistently infected Dami system provides a suitable model for clarifying its function.

Blotting, Southern↗

PubMed1993

Human foamy virus polypeptides: identification of env and bel gene products.

Human foamy virus (HFV) proteins were identified in human cells cultured in vitro by immunoprecipitation and immunoblotting with specific antisera. Among several viral polypeptides, four glycoproteins of approximately 160, 130, 70, and 48 kDa were identified in HFV-infected cells. gp130 was shown to represent the intracellular env precursor, and gp70 and gp48 were shown to represent the external and transmembrane env proteins, respectively. The nature of gp160, which shares sequences with the env, bel1, and bel2 proteins, is not yet resolved. In addition, a p62 identified with bel1- and bel2-specific antisera likely corresponds to the bet gene product.

Antibodies, Viral↗

PubMed1992

Circulating interferon in cytomegalovirus infected bone-marrow-transplant recipients and in infants with congenital cytomegalovirus disease.

In a study concerning five CMV-infected bone-marrow-transplant recipients, five congenital CMV diseases and appropriate controls, presence of high levels of circulating interferon (IFN) was demonstrated exclusively during the course of CMV disease. This interferon was predominantly "immune" or gamma interferon (gamma-IFN). These results suggest that during CMV disease the interferon compartment of the immune response is modified.

Anemia, Aplastic↗

PubMed1992

The effects of poly(I).poly(C12U) and interferon on the multiplication of a mammalian type C retrovirus in human cells.

Poly(I).poly(C12U) or interferon treatment inhibited multiplication of the xenotropic baboon type C endogenous retrovirus M7 in chronically infected human AV3-M7 cells, as determined by a reverse transcriptase (RT) assay and electron microscopy. Furthermore, this polynucleotide induced 2'5' oligoadenylate (2'5'A) synthetase activity. In contrast to interferon (IFN), poly(I).poly(C12U) did not give rise to the appearance of a trapping phenomenon observable by electron microscopy. When AV3-M7 cells were treated simultaneously with poly(I).poly(C12U) and anti-IFN-beta/alpha antibodies, the induction of 2'5'A synthetase was abolished without any alteration of the inhibitory effect of RT activity. Taken together, these results suggest that different mechanisms are used by poly(I).poly(C12U) and IFN in blocking type C retrovirus multiplication.

2',5'-Oligoadenylate Synthetase↗

PubMed1991

Further characterization of the gapped DNA intermediates of human spumavirus: evidence for a dual initiation of plus-strand DNA synthesis.

We recently reported the presence of linear duplex DNA intermediates with a gap in the middle of the molecules in the replicative cycle of human (HSRV) and simian (SFV1) spumaviruses. The polypurine tract (PPT), at the 5' boundary of the 3' long terminal repeat, was found to be duplicated in the gap region. By molecular analysis of HSRV proviral DNA with region- and strand-specific probes, we have now determined that the gap is located on plus-strand DNA and that it is 120 bases long with the 3' end mapping at the duplicated PPT site. Kinetic analysis of proviral DNA provided evidence that the gap did not result from processing of a complete, full-length DNA molecule. These data strongly suggest that plus-strand DNA synthesis is initiated at both PPT sites.

Base Sequence↗

PubMed1991

5' LTR complete nucleotide sequence of Chinese hamster intracisternal A-particle.

Retrovirus like sequences homologous to mouse IAP are present in Chinese hamster genome (Lueders K.K. and Kuff, E.L., 1981, 1983, Servenay et al., 1990). Murine IAP long terminal repeats (LTRs) can function as effective promoters in different cell types (Horowitz M. et al., 1984, Howe, C.C. et al., 1986). Thus CHO IAP sequences could act as retrotransposons in the cellular genome, and in this way affect the expression of other genes at the target sites. We had sequenced previously a Chinese hamster IAP genomic region corresponding mainly to the gag gene and including 57 nucleotides of U5 5' LTR (Servenay et al., 1988). In this paper, we present the 5' LTR complete nucleotide sequence of the Chinese hamster IAP element and its comparison with those of mouse and Syrian hamster.

Animals↗

PubMed1991

Biological and molecular studies of endogenous retrovirus-like genes in Chinese hamster cell lines.

Two types of endogenous retroviral-like sequences related to type C or Intracisternal A Particle (IAP) genes respectively were detected in the Chinese hamster (CH) genome. Their structure and expression were analysed by virological and molecular approaches in different CH cell lines. Several clones were isolated from a CHO genomic library by screening--in stringent conditions--with type C (Gross-MuLV) or IAP (pMIA1) specific probes. These clones were further characterized by restriction mapping and sequencing. Transcripts of type C and IAP-like retroviral sequences were revealed either by PCR or by Northern blot analysis and hybridization with the respective specific probes. However only a few retroviral-like type C particles and no IA particles were detectable by electron microscopy. Only weak activation of type C viral production by halogenated pyrimidines or other classical viral activation agents was observed. No replication of this virus could be obtained in rodent, canine, simian or human cell lines.

Animals↗

PubMed1990

Detection of IAP related transcripts in normal and transformed rat cells.

Intracisternal A-particles (IAP) genes in variable copy number exist in all rodent species studied. Expression is highly repressed in murine normal cells except in embryonic and transformed cells. We searched for IAP related sequences expression in another rodent species cells. Using the more conserved sequence of IAP gene between mouse, Syrian hamster, and rat species (0.4 kb HindIII-PstI fragment from PMIA14), we have been able to detect IAP related transcripts in rat cells. We found that, i) IAP related transcripts are poorly expressed in normal cells, since among 10 tissues tested, only the placenta shows IAP RNA. ii) IAPs are highly expressed in all the transformed cells tested. iii) the detected transcripts appear to have similar sizes in rat cells as in mouse cells (7.2 kb; 5.4 kb). None of the probes corresponding to other regions of the IAP gene nor the entire sequence of PMIA14 allowed us to detect such transcripts.

Animals↗

PubMed1990

High human T-cell lymphotropic virus type I proviral DNA load with polyclonal integration in peripheral blood mononuclear cells of French West Indian, Guianese, and African patients with tropical spastic paraparesis.

Human T-cell lymphotropic virus type I (HTLV-I) proviral integration status was examined by Southern blot analysis in peripheral blood mononuclear cell (PBMC) DNA from patients presenting a tropical spastic paraparesis (TSP) and serological evidence of HTLV-I infection. Surface phenotype and morphological aspects of PBMC were also studied. A polyclonal HTLV-I proviral integration was found in the PBMC of the 10 patients studied irrespective of their geographical origin (French West Indies, French Guiana, and Africa), the duration of their clinical illness, or the HTLV-I antibody titer. Furthermore, by dilution experiments and hypothesizing that only one copy of HTLV-I proviral DNA is present in one cell, we estimated that this HTLV-I integration is present in 3% to 15% of their PBMC. All 10 TSP/HTLV-I patients studied had an average of 10% of their lymphocytes abnormal, presenting either a misshapen nucleus or an adult T-cell leukemia/lymphoma (ATL)-like feature. Moreover, an elevated CD4/CD8 ratio associated with the presence of activated T cells with a high level of DR expression was observed in most patients. The significant frequency of viral-positive PBMC and the important load of HTLV-I proviral DNA that we observed in TSP/HTLV-I patients might play an important role in the pathogenesis of this recently identified clinico-virological entity.

Antibodies, Monoclonal↗

PubMed1990

Molecular cloning and characterization of retrovirus-like intracisternal type A particle genes (IAP) present in the Chinese hamster genome.

Endogenous retrovirus-like sequences that are homologous to the multigenic murine and Syrian hamster intracisternal type A particle (IAP) genes can be detected in very few copies in the Chinese hamster (CH) genome. They were cloned from a CHO gene library and two recombinants, harboring the major IAP-like DNA genes characterized by Southern blot hybridization after DNA digestion with several restriction enzymes. The IAP DNA inserts of the two clones analyzed were 4.70 and 8.04 kb respectively, allowing us to construct a physical map of our Chinese hamster clone that represents an almost complete IAP element.

Animals↗

PubMed1990

In vitro induction of early mouse embryo intracisternal particles (epsilon particles) in cultured cell lines.

The experimental induction of epsilon particles, retrovirus-like structures corresponding to the small IA particles of the mouse, was studied by electron microscopy in rodent-cultured cell lines. Among the chemicals tested, only IdUr was shown to be an effective inducer, but not cycloheximide, puromycin , deoxy-fluorouracil or 5-azacytidine. However, only two mouse-derived cell lines: Ki-BALB and FG 10, among 27 cell lines of mouse, rat and mink origins tested, expressed epsilon particles upon IdUr treatment. Epsilon particles thus respond to chemical inducers very differently in comparison with large IAP. Moreover, the addition of interferon previously shown to attenuate IAP production, had no effect on that of epsilon particles.

Animals↗

PubMed1990

Cell surface phenotype and human T lymphotropic virus type 1 antigen expression in 12 T cell lines derived from peripheral blood and cerebrospinal fluid of West Indian, Guyanese and African patients with tropical spastic paraparesis.

Twelve long-term cell lines were established from peripheral blood mononuclear cells (PBMC) or cerebrospinal fluid cells of patients with human T lymphotropic virus type I (HTLV-1) seropositive tropical spastic paraparesis (TSP) originating from the French West Indies, French Guyana or the Central African Republic. Most of these long-term interleukin-2-dependent cell lines exhibited a pattern characteristic of CD4(+)-activated T cells with high expression of CD2, CD3 and CD4 antigens, associated with a strong density of TAC and DR molecules. Nevertheless, in five cases CD8 expression was present at a significant level. HTLV-I antigens were never detected in uncultured PBMC, but they were expressed in a few cells after short-term culture and after 4 months the majority of the cells were HTLV-I positive, as demonstrated by indirect immunofluorescence (IF) using polyclonal or monoclonal anti-p19 and anti-p24 antibodies. Low and variable levels of reverse transcriptase activity were detected in supernatant fluids of these cell lines only after 4 months of culture, when at least 50% of the cells exhibited HTLV-I antigens by IF. However, numerous type C HTLV-I-like viral particles were detected, mostly in the extracellular spaces, with rare budding particles. Similar findings were found in three T cell lines derived from West Indian and African patients with adult T-cell leukaemia/lymphoma (ATLL). Differences in high Mr polypeptides were detected by Western blot in cell lysates when comparing TSP- or ATLL-derived T cell lines. Thus a signal of 62K was easily detectable in all the TSP lines, but not in the ATLL lines. In all cell lines bands corresponding to p53, p24 and p19 viral core polypeptides were present, as was the env gene-coded protein p46.

Adult↗

PubMed1989

Electron microscopic characterisation of retrovirus and retrovirus-like particles induced by demethylating agents (5-azacytidine and 5-azadeoxycytidine) in Syrian hamster (Mesocricetus auratus) cells.

In a framework of a study on retrovirus expression in Syrian hamster (mesocricetus auratus), three cell lines were examined by electron microscopy. As we had previously demonstrated the efficacy of demethylating drug in activating the formation of retroviral particles, we used 5-azacytidine to activate endogenous retrovirus expression. Proceeding to a more detailed survey we were able to observe various types of retrovirions. All of them were present in the different activated cell lines. They were: intracisternal R-type particles (IRP), intracisternal A-type particles (IAP), intracytoplasmic A-type particle (ICAP), intramitochondrial A-type particle (IMAP) and M-432 virus-like particles. Some of these particles have never been described before in Syrian hamster cells. The significance of their presence is discussed here.

Animals↗

PubMed1989

In vitro growth properties and PCR ras gene analysis of a murine embryonal carcinoma cell line harboring an amplified c-Ki-ras gene.

Ras proto-oncogenes are thought to be involved in both proliferation and malignant processes. We examined some growth properties of a murine embryonal carcinoma cell line (ECC), PCC4, that have been shown previously to be amplified for the c-KI-ras gene. Our results show that doubling time and plating efficiency are not significantly affected by such amplification. To examine the possible link between malignant behavior and c-Ki-ras alteration, we investigated activating mutations in this PCC4 cell line as well as in other ECC. Analysis of the in vitro amplified Ki-ras gene by PCR technology has not revealed point mutations in any of the ECC examined.

Animals↗