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J Y Muller

Publications and source records attributed to J Y Muller.

At least 73 records · Page 4Linked to original sources

HLA-associated susceptibility to acquired immune deficiency syndrome in HIV-1-seropositive subjects.

No difference in HLA-A, B or DR gene frequencies could be observed between 172 control subjects and 180 HIV-1-seropositive subjects of European ancestry diagnosed through the systematic screening of blood donations. In contrast, progression to acquired immune deficiency syndrome (AIDS; 21 patients) or CD4 lymphocyte loss equal or more than 20% over a 6-month period (37 subjects) was found to be associated with the B8DR3 haplotype (relative risk = 10.64, p less than 0.003, and 2.23, p less than 0.092, respectively). Other independently significant associations assessed through the multivariate Cox proportional-hazards model were B16, BW21 and B35 alleles as factors of bad prognosis. Conversely, A11 and DR4 alleles were factors favouring longer survival.

Acquired Immunodeficiency Syndrome↗

Influence of HLA-DP mismatches on primary MLR responses in unrelated HLA-A, B, DR, DQ, Dw identical pairs in allogeneic bone marrow transplantation.

The success of bone marrow transplantation relies on class I and class II HLA identity between donor and recipient but until now the impact of DP mismatches on primary mixed lymphocyte reaction (MLR I) responses has not yet been clearly established. HLA-DP typing has been performed by a RFLP method on 10 patients and their 22 selected potential donors (HLA-A, B, DR, DQ, Dw identical according to serological, RFLP and oligotyping methods). HLA-DP-matching was then correlated with MLR I responses obtained (1) in 22 HLA-A, B, DR, DQ, Dw identical donor-recipient pairs (patient series) and (2) in 30 HLA-A, B, DR, DQ, Dw identical donors pairs used as the control series. We showed that MLR I responses involving patients cells were always lower than those involving control cells (p less than 0.02 in case of two DP-mismatches and p less than 0.001 in the case of one DP-mismatch). Moreover, in the control series two or one DP mismatches influenced MLR I responses in 91% and 77% of the cases respectively; however, there was a greater scatter of response values which could be explained by the degree of sequence homology between the DP mismatched alleles. In cases with no DP mismatch, no proliferative response was observed. Overall, these results suggest that the conventional technical conditions of MLR I do not allow detection of mismatches other than the well known HLA specificities.

Bone Marrow Transplantation↗

[Lymphocyte surface antigens in the peripheral blood. Detection by flow cytometry. Applications to the immune system in clinical practice].

A flow cytometer enables observation of single cells providing morphological characterization of the cell and identification of cell markers. The cells pass a detection point where they are striked by a sharply focused beam. Light scattering by the cells gives informations about size and granularity. Detection of fluorescence emission permits identification of fluorescent tag such as antibodies. Flow cytometric analysis of immunologic phenotyping allows interpretation of weak fluorescence intensity and detection of two antigens on a single cell with dual fluorescence analysis. Evaluation of B and T cells and their subclasses from whole blood preparations, provides informations of immunological status. Immunophenotyping at the clinical level has been used in a variety of human diseases; immunophenotypic changes have been observed in congenital and acquired immunodeficiency syndromes and auto-immune disorders.

Antigens, Surface↗

[Early anomalies of CD4 and CD20 lymphocyte cycles in human immunodeficiency virus].

Circadian variations in the number of circulating lymphocytes and their subpopulations have been observed in healthy subjects. These cyclic changes are characterized by a trough at 8:00 a.m. and a peak at midnight. Using multiple peripheral blood samplings, we were able to confirm that this cycle applied to CD4 T-cells (helpers) and to B-cells (CD20). No cycle of CD8 lymphocytes was observed. In a second stage, for greater comfort of the patient the number of samplings was reduced to two: one at 8:00 a.m. (trough) and one at midnight (peak). This method enabled us to calculate the amplitude of lymphocytes cycles in 18 controls and 74 human immunodeficiency virus (HIV) seropositive patients. In asymptomatic HIV carriers the amplitude of CD4 cycles was normal in 6/26 cases and that of B-cell cycles in 2/17 cases. In the group of asymptomatic HIV carriers the mean amplitude of the cycles was much less reduced than in the other two groups. These results incite us to believe that the loss of the CD4 T-cell cycles is an early sign of HIV infection antedating the decrease observed in the number of these cells.

Adult↗

[Platelet phenotyping and study of alloantibodies using flow cytometry].

In this study, we describe a flow cytometric technic for the detection and characterization of platelet allo antibodies and for platelets grouping in the platelet group PLA. This new technique is a variant of the platelet suspension immuno fluorescence test. It is rapid, simple, sensitive and specific. So it is very useful in the cases of neonatal thrombocytopenia and posttransfusion purpura. Moreover, anti-HLA antibodies don't obstruct the detection of anti-PLA1 antibodies.

Antigens, Human Platelet↗

Disappearance of CD4-lymphocyte circadian cycles in HIV-infected patients: early event during asymptomatic infection.

Circadian variations have been observed in peripheral blood lymphocyte counts in normal subjects; they usually reflect variations in absolute CD4-cell count. For this population, nadir occurs around 0800 h (basal value) and the peak value occurs at midnight (1.6 times the 0800-h value). This cycle is thought to be of major importance in the efficacy of the immune response because it expresses the migration of lymphocytes into lymphoid organs.

Acquired Immunodeficiency Syndrome↗

Follow-up of subjects with isolated and persistent anti-core (anti-p24 or anti-p17) antibodies to HIV.

Systematic screening of blood donations by enzyme-linked immunosorbent assay (ELISA) for HIV antibodies carries a false-positive rate: the sera involved react in Western blot to core antigens (p24 or p17) but reactivity to envelope is absent. We studied 22 subjects with persistent and isolated anti-core reactivities; 75 HIV seropositive patients were controls. The epidemiological data and the follow-up and biological tests performed in these two populations argue that donors with persistent and isolated anti-core antibodies are not seroconverting for HIV. We conclude: (1) that verification of all anti-HIV ELISA-positive sera by Western blot is essential and that the presence of at least once anti-envelope (gp120 or gp41) antibody is indispensable for the diagnosis of HIV infection; (2) that the solitary anti-p24 or anti-p17 bands observed on Western blot are false-positive. There is no evidence that donors with such reactivities are HIV-infected.

Adult↗

Definition of DRw10 specificity by restriction fragment length polymorphism.

The purpose of this study was the RFLP characterization of the DRw10 specificity. Twenty-two DRw10 cells were tested: the DNAs were digested by seven restriction enzymes and hybridized with DR beta, DQ beta and DQ alpha probes. Hybridization with DR beta revealed a pattern particular to the DRw10 specificity, with a specific TaqI 12.5Kb fragment. Hybridization with both DQ-specific probes showed that DRw10 is always associated with a special DQw1 subtype: DQw5. Furthermore, at DR and DQ levels, the 22 DRw10 cells behaved homogeneously.

Alleles↗

HLA class II genes polymorphism in DR4 giant cell arteritis patients.

We have previously reported a significant increase of HLA-DR4 antigen frequency in giant cell arteritis (GCA). This finding suggested an important role of immunogenetic factors in this syndrome. Recent data suggest that inherited susceptibility to several autoimmune diseases was associated with specific DR4 associated DQ beta alleles. DNAs from 27 DR4 positive patients with GCA were digested with Taq I and Bam HI, analysed on 0.7% agarose gel and hybridized with DR beta, DQ alpha and DQ beta probes. DR beta hybridization produced no variant detectable within DR4. DQ beta probe confirmed two clusters among DR4 associated DQW3 alleles: DQW 3.1 (Bam HI 360 Kb) and DQw 3.2 (Taq I 1.9 Kb and Bam HI 11 Kb). Among our 27 DR4 positive patients, 34% were DQW 3.1 and 66% were DQW 3.2. These frequencies are the same as those observed in healthy controls.

DNA↗

Platelet antibodies in systemic lupus erythematosus.

In systemic lupus erythematosus (SLE), the precise cause of the thrombocytopenia is unknown. Since platelet associated IgG is increased in many patients, it has been suggested that the destruction of platelets might be dependent on specific antibodies. In nine patients with SLE, platelet associated immunoglobulins were found together with free serum antibody which bound to platelets from all normal subjects. Using an immunoblotting technique with membrane proteins from normal platelets incubated with patient sera, target antigens were localized on a band of mol wt 108,000 in two cases (B. and N.) and on a band of mol wt 66,000 in a third (M.). When the same technique was applied to autologous platelets of patient N., autoantibody binding to the protein of mol wt 108,000 was demonstrated. The antigenic determinants were not removed from the platelets by enzyme treatment or by disulphide bond reduction, and were localized in the cytoplasmic fraction of the platelets.

Autoantibodies↗