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A Gessain

Publications and source records attributed to A Gessain.

At least 145 records · Page 8Linked to original sources

[HTLV-I retroviral variant in Zaire in patient with chronic neuromyelopathy. Nucleotidic sequence of the envelope gene].

The oncoretrovirus HTLV-I is the etiological agent of adult T cell leukemia (ATL) and tropical spastic paraparesis/HLTV-I associated myelopathy (TSP/HAM). In contrast to the human lentiretroviruses, HIV-I and HIV-2, the causative agents of AIDS, HTLV-I is genetically very stable. We report here the molecular characterization of the envelope gene of an HTLV-I variant present in a TSP/HAM patient from Zaïre, raising the question of its relevance to disease or the ethnic and/or geographical origin of the patient.

Base Sequence↗

[Investigation of a transfusion contaminated by HTLV-I virus].

In front of the successive development of an HTLV-I seroconversion and a neuromyelopathy in a French Caucasian following a cardiac transplantation, an ascendant epidemiologic investigation must be manage to search a risk factor or a possible blood donor contaminated with HTLV-I virus. We selected an HTLV-I seropositive donor whose RBC participated to the patient's transfusion. This woman from Martinique island was a regular donor in our blood center and a second investigation was initiated to examine the patients transfused with the blood products issued from her previous donation. Nine were identified and controlled among them a patient who has received a RBC was found HTLV-I seropositive. An evaluation of the infectivity of the different blood products according to their type and specificity has been done. These data confirm that transmission of the HTLV-I is possible through donation of healthy seropositive donor and can induce the development of associated pathology, and prove the importance of screening blood donors for HTLV-I antibodies.

Adult↗

Human T-cell leukemia-lymphoma virus type I (HTLV-I) expression in fresh peripheral blood mononuclear cells from patients with tropical spastic paraparesis/HTLV-I-associated myelopathy.

Tropical spastic paraparesis/human T-cell leukemia-lymphoma virus type I (HTLV-I)-associated myelopathy (TSP/HAM) is a chronic neurological illness epidemiologically associated with HTLV-I infection. We investigated the role of HTLV-I in the pathogenesis of this disease by studying viral expression in fresh uncultured peripheral blood mononuclear cells (PBMCs) of six patients of Caribbean origin with TSP/HAM. The PBMC genomic DNA of all the patients studied carried HTLV-I provirus, but viral expression was not detected by Northern (RNA) blot analysis of total cellular PBMC RNA. When the reverse transcriptase polymerase chain reaction technique was used with primers specific for the tax-rex mRNA, all of the samples were positive for this viral mRNA species, regardless of the duration of the illness (range, 2 to 13 years). The splice junctions for the tax-rex mRNA described in cases of HTLV-I-induced adult T-cell leukemia (position 5183 of the envelope and position 7302 of the pX region) were identical in three TSP/HAM cases studied. To ascertain whether viral expression occurred at a low level in many cells or at a high level in a few permissive cells, we performed in situ hybridization on fresh PBMCs from two patients (2 and 7 years after clinical diagnosis), seeking HTLV-I RNA sequences. Our finding indicated that in vivo HTLV-I expression occurred at a high level in a few cells (1 of every 5,000 PBMCs) in both cases studied. The fact that cells of all six patients with TSP/HAM were positive for viral expression, regardless of the time lag from diagnosis, suggests that persistent expression of a viral product(s) may be pivotal in the pathogenesis of TSP/HAM.

Adult↗

Antibodies to gag gene coded polypeptides of type D retroviruses in healthy people from Guinea-Bissau.

Antibodies to proteins of Mason-Pfizer monkey virus (M-PMV) were screened in sera from 61 healthy donors living in Guinea-Bissau (4 HIV-1 and HIV-2 antibody positive HIV = human immunodeficiency virus), from 19 healthy French European blood donors, and from 9 French patients with induced immunodeficiency prior to bone marrow transplantation (all HIV-1 antibody negative). In 30 (49%) of the African sera tested, antibodies reacting against p27 and/or p14 were detected by western blot. Some of these cases were confirmed to be positive using radioimmuno precipitation assay. Only one serum from a French blood donor was detected by western blot to be slightly positive against p27 M-PMV. Thirty-two sera screened for M-PMV were also tested for squirrel monkey retrovirus by western blot. In eight (25%) sera antibodies at least against p36 were detected. Among squirrel monkey retrovirus positive sera, three were also positive with p27 M-PMV. The other five were found to be M-PMV negative.

Adolescent↗

MS and HTLV-I.

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Diagnosis, Differential↗

No evidence for HTLV-I infection in 24 cases of French and Portuguese mycosis fungoïdes and Sezary syndrome (as seen in France).

A survey in search of evidence for HTLV-I infection was conducted on French and Portuguese patients residing in France with a diagnosis of mycosis fungoïdes or Sezary syndrome. Methods used in this investigation included serological assays (ELISA, Western blot, particle agglutination, indirect immunofluorescence) and DNA molecular studies (Southern blot and polymerase chain reaction). Cultures of peripheral blood mononuclear cells were performed and checked by electron microscopy and reverse transcriptase assay. The results indicate that neither HTLV-I nor a closely related retrovirus are associated with mycosis fungoïde or Sezary syndrome in the cases studied.

Adult↗

Epidemiology and immunovirology of human T-cell leukemia/lymphoma virus type I-associated adult T-cell leukemia and chronic myelopathies as seen in France.

Seventeen patients with adult T-cell leukemia (ATL) and 21 with tropical spastic paraparesis/human T-cell leukemia/lymphoma virus type I (HTLV-I)-associated myelopathy (TSP/HAM) were observed during a 3-yr survey (1986-1988) in some hospitals in Paris, France. Most of them were black, originating from high-HTLV-I-endemic areas (West Indies or Africa), but two cases of TSP/HAM occurred in French Caucasians. In one case, the patient acquired the virus from a transfusion during a cardiac transplantation. Most of the ATL cases were diagnosed as acute leukemia or lymphoma, with a proliferation of CD2+, CD3+, CD4+, CD8-, DR+, and CD25+ lymphoid cells. Only three cases were diagnosed as a smoldering ATL. All of the TSP/HAM cases exhibited a spastic paraparesis with a chronic and slow evolution and high HTLV-I antibody titers in serum and cerebrospinal fluid, with a high HTLV-I antibody index and specific HTLV-I immunoglobulin = oligoclonal bands. In TSP/HAM, a high percentage of DR-expressing cells (15 to 40%) was found, with a slightly elevated CD4/CD8 ratio. This was associated with the presence of 1 to 10% abnormally shaped nuclei in lymphoid cells and a polyclonal integration of HTLV-I proviruses in these peripheral blood mononuclear cells. On the contrary, a clonal integration was always found in the ATL malignant cells (leukemic, lymph node, and cutaneous infiltrate). Long-term interleukin 2-dependent T-cell lines (CD2+, CD3+, CD4+, and WT31+) with activated T-cell markers (CD25+ and DR+) producing HTLV-I were established from ATL and TSP/HAM peripheral blood mononuclear cells.

Antigens, CD↗

[Adult T-cell leukemia and non-malignant adenopathies associated with HTLV I virus. Apropos of 17 patients born in the Caribbean region and Africa].

Adult T-cell leukaemia is the first blood disease caused by a retrovirus: HTLV-1. The authors report the first French series of 15 patients, of whom 9 came from the classical endemic areas--the Antilles and outer Caribbean Islands--and 6 from Africa where the serological prevalence of HTLV-1 is high but few cases of adult T-cell leukaemia have been reported. Emphasis is laid on the importance of immunodeficiency (refractory strongyloidiasis, Pneumocystis carinii pneumonia, polyclonal B lymphoproliferative syndrome) and of other pathologies associated with the retrovirus (polyarthritis, lymphocytic interstitial pneumonia). The authors also describe the presence of adenopathy in healthy carriers: either adenitis suggestive of retroviral infection, or Castelman's disease adenopathy. These clinical presentations are similar to those described in lymphadenopathy syndromes due to the human immunodeficiency viruses. Aggressive lymphomas require chemotherapy, but sooner or later resistance develops, and the prognosis is very poor. The indications for allogeneic bone marrow transplantation are still to be determined. The diagnosis of adult T-cell leukaemia must be considered in all patients with blood disease coming from the endemic areas.

Adult↗

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↗

Cutaneous type of adult T cell leukemia/lymphoma in a French West Indian woman. Clonal rearrangement of T-cell receptor beta and gamma genes and monoclonal integration of HTLV-I proviral DNA in the skin infiltrate.

A 45-year-old woman, a native of the French West Indies who had lived in France since 1973, developed multiple cutaneous plaques and nodules in 1987. Histopathologic studies revealed dermal infiltration with mature activated T cells (CD4+, CD25+, DR+) with nuclear convolutions and epidermatotropisim. High titers of specific human T lymphotropic virus (HTLV)-I antibodies were detected in the serum. Molecular analysis of DNA extracted from the skin tumor biopsy specimen showed a clonal integration of an HTLV-I provirus and a T-cell clonal population as demonstrated by T-cell receptor beta and gamma gene rearrangement studies. Neither HTLV-I provirus nor T-cell receptor rearrangements were detected in peripheral blood mononuclear cells DNA despite the presence of rare adult T cell leukemia cells (less than 1%) and a small excess of DR-expressing cells, and detection of HTLV-I Pol and Px sequences by in vitro gene amplification. In this case only gene analysis of the skin lesions made possible an early diagnosis of a cutaneous adult T cell leukemia. This illustrates the need for such molecular studies to differentiate, in HTLV-I seropositive patients from endemic areas, a HTLV-I-induced T cell lymphoma from HTLV-I-nonrelated cutaneous T cell lymphomas.

Antigens, CD↗

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↗

Rearrangements of the T cell receptor delta gene in T acute lymphoblastic leukemia cells are distinct from those occurring in B lineage acute lymphoblastic leukemia and preferentially involve one V delta gene segment.

Rearrangement of the TCR-delta gene was studied using J delta, C delta, and V delta probes in 61 cases of acute lymphoblastic leukemia (ALL) and several cases of chronic lymphoid neoplasms to define the specificity and the diversity of rearrangements occurring at the delta locus. TCR-delta rearrangements or deletions were found in all T (33 cases) and B lineage (28 cases) ALL but not in any case of B cell chronic proliferations (13 cases). The restriction patterns of rearrangement were clearly distinct between T and B ALL and use of one V delta probe showed that rearrangement of the V delta IDP2 gene segment which is also productively rearranged in the Peer cell line, occurred frequently in T-ALL but never in B lineage ALL. Studies of WT31 and delta TCS1 antibody reactivity showed that at least 4 of 13 CD3+ T-ALL cases expressed the delta protein. CD4 and/or CD8 Ag expression were observed in some of the gamma delta expressing T-ALL. These data show that particular TCR-delta gene rearrangements occur in neoplastic early B cells and that the combinatorial diversity of TCR-delta rearrangements in T cells is higher than initially expected. In addition this study shows that an important proportion of CD3 positive T-ALL cases express the gamma delta heterodimer.

Antigens, Differentiation, T-Lymphocyte↗

Characterization of HTLV-I isolates and T lymphoid cell lines derived from French West Indian patients with tropical spastic paraparesis.

Lymphoid cell lines derived from the peripheral blood of French West Indian patients with HTLV-I sero-positive Tropical Spastic Paraparesis and HTLV-I isolates were characterized. While patients' peripheral blood lymphocytes did not express detectable HTLV-I antigens when uncultured, they did so after short-term culture. Established cell lines were of T-cell lineage: CD2+, CD3+, CD4+, CD7+, WT31+ with activated T-cell markers CD25+, DR+ and a clonal rearrangement of the beta and gamma genes of the T-cell receptor. HTLV-I antigens were detected in cell lines by indirect immunofluorescence, Western blot and radio-immunoprecipitation assays. After 4 months in culture, low levels of Mg2+ dependent reverse transcriptase activity were detected and electron microscopy revealed numerous type-C retroviral particles similar to HTLV-I virions. Western blot and radio-immunoprecipitation analysis of purified viruses revealed gp46, p24, p19 and Pr53gag proteins similar to those detected in HUT 102 and MT2 cell lines. Deep analysis of env-coded precursor of one TSP versus ATL isolates revealed minor differences in their molecular weights. Southern blot analysis using 32P HTLV-I env gene as a probe showed the presence of HTLV-I proviral fragments clonally integrated into the genome of the cell lines. Our data suggest that HTLV-I isolated from Tropical Spastic Paraparesis does not differ significantly from the leukemogenic prototypes. Does HTLV-I induce either acute lymphoproliferative diseases or chronic neuromyelopathies depending upon as yet unknown co-factors? This question remains to be determined.

Blotting, Southern↗

Chronic myelopathies associated with human T-lymphotropic virus type I. A clinical, serologic, and immunovirologic study of ten patients in France.

Chronic myelopathy associated with human T-lymphotropic virus type I (HTLV-I) has been described in HTLV-I endemic areas. In Paris, 167 neurologic patients were screened for HTLV-I by enzyme-linked immunosorbent, indirect immunofluorescent, and Western blot assays. Ten of the 11 patients with positive results had a chronic spastic paraparesis with IgG oligoclonal bands and elevated HTLV-I antibody index. Two of them had been born and were living in France, without HTLV-I risk factors. Evoked potentials were abnormal in the nine tested patients and brain magnetic resonance images in three of seven patients. No improvement was observed with steroid treatment. A retrovirus similar to HTLV-I was isolated in five cases at different periods of the disease. Hypotheses of limited endemic areas in western countries are discussed. Early presence and persistence of HTLV-I suggest that it is the etiologic agent.

Adult↗

Chronic progressive myelopathy associated with HTLV-I: oligoclonal IgG and anti-HTLV-I IgG antibodies in cerebrospinal fluid and serum.

Among 22 patients with human T-lymphotropic virus type I (HTLV-I)-associated chronic progressive myelopathy, agarose isoelectric focusing (AIF) revealed oligoclonal IgG bands in 21: in 3 in CSF only; in 11 in CSF and to some extent in serum; and in 7, identical patterns in CSF and serum. By immunoblot after AIF of CSF and serum, we observed bands of anti-HTLV-I IgG antibodies in 19 patients: in 5 in CSF only; in 9 in CSF and partly in serum; and in 5, identical in CSF and serum. Oligoclonal anti-HTLV-I IgG antibody bands could only partly be traced to oligoclonal IgG bands. If, prior to AIF, serum and CSF were absorbed with HTLV-I antigen, practically all oligoclonal HTLV-I-specific IgG antibody activity was abolished, while the oligoclonal pattern of total IgG was affected only to a minor extent. Alongside with HTLV-I-specific oligoclonal B cell response, HTLV-I myelopathy is regularly accompanied by production of oligoclonal IgG of unknown antibody specificities.

Adult↗