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J D Bignon

Publications and source records attributed to J D Bignon.

At least 37 records · Page 2Linked to original sources
PubMed1993

Specificity of T cells invading the skin during acute graft-vs.-host disease after semiallogeneic bone marrow transplantation.

The mechanisms responsible for skin lesions during acute graft-vs.-host disease (aGVHD) after allogeneic bone marrow transplantation (BMT) are poorly understood. The exact role of various effector cell populations and "major" (particularly HLA-DP) or "minor" antigens as target molecules is not known. To investigate the nature of cells responsible for tissue injury, we cultured T cells from skin biopsy first with interleukin 2 (IL-2) alone and then in polyclonal activation conditions to avoid in vitro antigenic sensitization before specificity testing. We applied this method to two biopsies performed during aGVHD after semiallogeneic BMT and obtained cytotoxic T cells against four graft mismatches: CD8+ T cells against HLA-A2.2 and HLA-B27 and CD4+ T cells against HLA-DP101 and HLA-DP401. This demonstrates that T cells with documented specificity can be obtained from an aGVHD lesion without antigenic selection. Moreover, these data directly implicate DP as a potential target antigen for aGVHD.

Adult↗
PubMed1993

[Immunological treatment of spontaneous repeated abortions. The value of transfusing the partner's leukocytes in the third week of gestation].

Twenty-two nulli- all primipara who had had previous repeated spontaneous abortions and who did not have anti-HLA antibodies for the partner, received immunological treatment consisting of a single transfusion of the partner's lymphocytes in the third week of pregnancy, and giving natural progesterone supplements after the kinetic of Beta-HCG in the plasma had been assessed. The number of pregnancies which went to terme (94% success) was significantly better than those obtained in our first protocol which was to give one to three transfusions of the partner's lymphocytes before the pregnancy started (58% success rare after 24 treatments). Apart from obtaining much better results the second protocol made it possible to avoid giving a significant number of useless transfusions (22% of pre-conceptual transfusions were not followed by a pregnancy at all).

Abortion, Habitual↗
PubMed1992

DNA typing: an important step forward? Collaborative Transplant Study.

In a collaborative project which was supported by 96 transplant centers, DNA typing of HLA-DR antigens was carried out on over 7,000 transplant donors and recipients at 8 participating laboratories. Approximately 25% of the individuals were found to have been typed incorrectly by serological means. An analysis of over 2,500 first cadaver kidney transplants showed a significant correlation of matching for the HLA-DR antigens in transplants where the serological typing was confirmed by DNA typing. In transplants where the serological typing was found to be incorrect, the analysis of serological HLA-DR mismatches resulted in no correlation with graft outcome whereas a significant correlation was found when the corrected DNA typed HLA-DR antigens were analyzed. Transplants which had been reported to the Collaborative Transplant Study based on serological typing as matched for HLA-A, -B, -DR or HLA-B, -DR were found to have a superior graft survival rate only if HLA-DR compatibility was confirmed by DNA typing.

DNA Fingerprinting↗
PubMed1992

Multifactorial analysis of the outcome of 6430 cadaver kidney grafts.

A total of 6430 cadaver kidney grafts performed within the network of France-Transplant between 1 January 1978 and 1 January 1989 were analyzed. Each case was examined comprehensively in regard to 12 variables. A multifactorial analysis (Cox regression) was used to determine the degree of association between each covariate and the outcome of the graft. The results were evaluated by calculating relative risks of graft failure for each variable. A total of seven covariates appeared to influence graft survival significantly: the period of transplantation (P = 10(-8)), retransplantations (P = 0.003), age and sex of the donor (P = 0.003 and 0.009 respectively), duration of pretransplant dialysis (P = 0.03), pretransplant sensitization to HLA antigens (P = 0.05), and matching for HLA-A, -B, and -DR loci (P = 0.03). This last parameter has previously been reported as influencing the outcome of the graft in seven out of eight international studies carried out using similar methodology.

Adolescent↗
PubMed1992

Crucial role of the third and fourth hypervariable regions of HLA-DPB1 allelic sequences in the mixed lymphocyte reaction.

Since HLA-DP mismatches are known to induce proliferative response in MLR I, we investigated the real impact of the different DP alleles and the possible role of one or several hypervariable regions of the DPB allelic sequences. Accordingly, we performed MLR I between HLA-A, B, DR, DQ, and Dw identical individuals DP oligotyped after DNA amplification. A total of 23 one-DP-mismatched healthy stimulator and responder cells displaying nine different DP specificities were thus evaluated in 52 MLRs I. This allowed us to analyze the impact of amino acid composition of each of the six hypervariable regions independently of the amino acid matching or mismatching in the five others. We show here that DP combinations sharing the same amino acid sequence in the third (C) and fourth (D) hypervariable regions are associated with a low proliferative response in vitro (p less than 0.01). These data imply that a perfect HLA-DP matching may not be requisite in selecting bone marrow donors. Indeed, the choice of donors may rely on determination of these particular mismatched HVRs between the DP alleles involved especially in GvHD direction. This policy including prospective DP oligotyping should be of great interest, especially when MLRs I are false negative or nonevaluable. It will enable a better definition of which DP mismatches are acceptable in BMT.

Alleles↗
PubMed1992

The influence of HLA A-B-DR matching on cytomegalovirus disease after renal transplantation. Evidence that HLA-DR7-matched recipients are more susceptible to cytomegalovirus disease.

We examined the prevalence of cytomegalovirus infectious episodes, as defined by clinical, virological, and serological criteria (i.e., CMV disease), in 660 kidney graft recipients; 109 patients (16.5%) developed the disease, and 551 did not. No significant statistical link between CMV disease prevalence and a given HLA-A, -B, or -DR allele was observed. However, patients with HLA-DR7 matched grafts were statistically more frequently found (P < 0.01) in the group of recipients who developed CMV disease as compared with the group who did not develop CMV disease. Furthermore, among patients who developed CMV disease, a significant increase of HLA-DR7 matched over DR7 mismatched patients was noted, whereas no difference between matched and mismatched recipients for the other HLA-DR alleles was found. No difference in the severity of graft failure, often observed during, or immediately after, the CMV episode, was noted between patients matched or mismatched for HLA-DR7. Our data suggest that donor/recipient matching for HLA-DR7 is associated with increased CMV disease.

Alleles↗
PubMed1991

Survival of DNA HLA-DR typed and matched cadaver kidney transplants. The Collaborative Transplant Study.

The clinical value of serological HLA matching for cadaver kidney transplantation remains uncertain because the success rate for HLA-matched cadaver transplants is lower than that of HLA-matched sibling grafts. Up to 25% of serological HLA-DR typings may be incorrect when compared with a more accurate DNA-RFLP method, and we have now examined whether incorrect HLA-DR typings account for the lower than expected success rates of HLA-matched cadaver transplants. 58 transplant centres took part in this study and DNA was extracted from over 4000 samples of frozen tissue at the study centre. 8 laboratories then completed blind RFLP typing for HLA-DR. Serological typing data were reported by individual transplant laboratories. 29 of 107 transplants (27%) that were reported as HLA A, B, DR compatible and 76 of 273 (28%) transplants that were reported as HLA B, DR compatible according to serological typing were found to be HLA-DR mismatched by DNA typing. The one-year transplant success rate for DNA-matched HLA, A, B, DR grafts was 87% compared with 69% for mismatched grafts (p less than 0.02); the corresponding success rate for DNA-matched HLA B, DR grafts was 85% compared with 72% for mismatched grafts (p less than 0.01). Many transplants that were previously thought to be HLA matched are mismatched, and this finding may account for previously unexplained graft failures.

Cadaver↗
PubMed1991

Effect of the number of pregraft blood transfusions in kidney graft recipients treated with bioreagents and cyclosporin A.

The impact of a systematic, nondonor-specific, pregraft blood transfusion (BT) protocol was evaluated retrospectively in 446 consecutive, first renal transplant recipients with regard to graft survival rate, rejection, and incidence of infectious episodes. Cyclosporin A was the maintenance immunosuppressive treatment in all patients after a 2-week course of antithymocyte globulin or anti-IL-2 monoclonal antibody. Recipients were assigned to three groups according to the number of pregraft BT (one or two, three or four, or more than four). When nonimmunological failures were excluded from the study, patients receiving three or four BT had statistically better graft survival (P less than 0.02) and a lower incidence of rejection episodes (P less than 0.05) than those in the other groups. There were no significant differences between the three groups in the distribution of HLA mismatching (A, B and DR), time interval between the last BT and transplantation, DR6 recipient phenotype, or nonimmunological failures. Our results show that the number of pregraft BT is an important factor in transplantation.

ABO Blood-Group System↗
PubMed1991

[HLA class II DP antigens and bone marrow transplantation].

The biochemical structure of the HLA class II DP antigens is close to that of the remainder DR and DQ isotypes. Nevertheless, they may play a peculiar functional role. Their importance in bone marrow transplantation, where a complete HLA class II identity between graft donor and recipient is requested, is not yet known. The detection of a DP mismatch by using the mixed lymphocyte reaction is quite difficult. The role of such a mismatch in the incidence of graft versus host disease (GVHD) or graft rejection has to be defined. Studies on large series of recombinant families, using oligotyping, are necessary.

Bone Marrow Transplantation↗
PubMed1991

No evidence of HTLV-I infection in French patients with multiple sclerosis using the polymerase chain reaction.

The polymerase chain reaction (PCR), using three primer pairs in the pol, tax, and env regions of the HTLV-I genome, was unable to detect HTLV-I in the blood samples of 54 caucasian subjects with multiple sclerosis who were seronegative for HTLV-I/II. Seventeen HTLV-I/II seropositive (by ELISA and Western blot) subjects used as positive controls were positive with the three primer pairs. The PCR was negative in 47 healthy HTLV-I/II seronegative (by ELISA) subjects at low risk of HTLV-I infection used as negative controls. These results suggest that there is no association between the occurrence of HTLV-I sequences and the development of multiple sclerosis.

Adult↗