Search PubMed⌕ Search

Biomedical subjects

G Opelz

Publications and source records attributed to G Opelz.

At least 235 records · Page 13Linked to original sources
PubMed1989

B lymphocyte response as an indicator of acute renal transplant rejection. II. Pretransplant and posttransplant B cell responses of m mitogen and donor cell-stimulated cultures.

In a prospective study we investigated the association of kidney graft rejection with pre- and posttransplant B cell responses in vitro after stimulation with pokeweed mitogen, Staphylococcus aureus Cowan I (SAC I), or donor lymphocytes. B cell differentiation was assessed in a reverse hemolytic plaque assay. Elevated pretransplant PWM- or SAC I-stimulated B cell responses were found to define patients with a high incidence of rejection episodes in the first 30 days posttransplant (P less than 0.005 and P less than 0.05, respectively). Elevated pretransplant donor cell-stimulated B cell responses were associated with a high risk of irreversible rejection (P less than 0.005). A posttransplant rise in donor cell-stimulated B cell responses was associated with an increase risk of a subsequent rejection crisis (P less than 0.05). Our data suggest that patients at risk of early rejection may identified by pretransplant testing of B cell responses.

Antibody-Producing Cells↗
PubMed1989

Lymphocyte autoantibodies and alloantibodies in HIV-positive haemophilia patients.

Immune parameters were studied in 86 haemophilia patients (six with AIDS) and 87 healthy controls. We found lymphocytotoxic alloantibodies in HIV-positive (HIV+) sera which reacted preferentially with B lymphocytes but also with T lymphocytes, and which reacted more frequently at 4 degrees C than at 37 degrees C. The antibodies were not directed against HIV-induced structures on T lymphocytes and they were reactive with both CD4+ and CD8+ lymphocytes. In addition to cytotoxic alloantibodies, cytotoxic autoantibodies were detected which coated patient lymphocytes in vivo. Increased proportions of in vivo-antibody-coated-cells were found in 37 of 86 haemophilia patients. Antibody binding was labile so that the immunoglobulins were partially removed from the lymphocyte surface by washing. The autoreactive antibodies were of IgG and IgM type, fixed complement as demonstrated by increased anti-C3d+ cells in the patients' blood, and reacted with CD4+ as well as CD8+ lymphocytes. There was a statistically significant correlation of increased Ig+ cells with HIV infection, decreased CD4/CD8 ratios, increased serum neopterin levels, and abnormal in-vitro responses to pooled allogeneic stimulator cells or CD3 monoclonal antibody. Patients with increased Ig+ cells were lymphopenic, had decreased absolute counts of CD4+, CD25+, CD21+ and OKM5+ cells, and higher percentages of CD8+ and OKIa1+ cells in their blood than patients with normal levels of Ig+ cells. Our data suggest a role of autoreactive anti-lymphocyte antibodies in the pathogenesis of acquired immunodeficiency.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Importance of HLA antigen splits for kidney transplant matching.

Whether matching for HLA antigen "splits" results in better transplant outcome than matching for "broad" HLA antigens was investigated in 30,000 first cadaver kidney transplants. At three years, there was an 18% difference between the survival rates of grafts with 0 or 4 mismatches among transplants typed for HLA-A and B antigen splits whereas the difference in transplants typed for broad antigens was only 2%. Analysis of HLA-A, B antigens together with HLA-DR antigens showed an even greater advantage of matching for antigen splits: the difference in survival at three years between grafts with 0 or 6 mismatches for HLA-A, B, DR was 31% when antigen splits were analysed, in contrast to a 6% difference with broad antigens. These results indicate that typing for HLA antigen splits is important in renal transplantation, that the potential benefit of HLA matching in renal transplantation is greater than currently accepted, and that HLA typing and kidney allocation routines must be refined in order to exploit this potential.

Cadaver↗
PubMed1988

The benefit of exchanging donor kidneys among transplant centers.

Whether kidneys from cadaver donors should be exchanged among transplant centers is controversial. We analyzed the effect of matching for HLA-B and HLA-DR antigens on graft survival in patients treated with cyclosporine. The results in 9369 recipients of kidneys obtained and transplanted in the same center were compared with those in 5553 recipients of kidneys shipped from one center to another. In both patient subgroups, the association of HLA matching with graft survival was statistically significant (P less than 0.0001). Moreover, well-matched exchanged kidneys survived better than poorly matched locally transplanted kidneys. Among patients receiving their first cadaver transplant, graft survival at one year was 13 percentage points higher (P less than 0.0001) in exchanged kidneys without mismatches than in local kidneys with four mismatches. Among patients receiving their second transplant, graft survival was 21 percentage points higher (P less than 0.001). Kidney preservation for up to 48 hours did not affect graft survival significantly. Transplantation of poorly matched local kidneys preserved with a short period of cold ischemia (less than 24 hours) had significantly lower rates of success than did transplantation of well-matched exchanged kidneys with a longer period of cold ischemia (up to 48 hours) (P less than 0.0001). Our data indicate that the exchange of cadaver kidneys among transplant centers to obtain grafts with better HLA matching can improve the success rate of renal transplantation.

Cadaver↗
PubMed1988

Priority allocation of cadaver kidneys to highly presensitized transplant recipients. Collaborative Transplant Study.

Within a prospective program of priority kidney allocation to highly presensitized recipients, 100 first and second cadaver transplants were performed from April 1985 to July 1987. The patient survival rate was 93% at 1 year. Graft survival at 1 year was 71% for first transplants and 68% for second transplants. There was a statistically significant correlation of graft outcome with matching for HLA-DR (P less than 0.02) and for HLA-B and -DR (P less than 0.02). The results demonstrate that multicenter cooperation is advantageous for the transplantation of highly presensitized recipients and that acceptable success rates can be obtained.

Antilymphocyte Serum↗
PubMed1988

Influence of recipient and donor age in pediatric renal transplantation. Collaborative Transplant Study.

The influence of recipient and donor age on the outcome of first cadaver kidney transplants was analyzed in a series of 1325 pediatric recipients and in 4230 transplants from pediatric kidney donors. Graft survival improved significantly with increasing recipient age (P less than 0.0001) and donor age (P less than 0.0001). Combined analysis of recipient and donor age groups revealed an overriding effect of donor age on graft outcome. Kidneys from donors younger than 3 years old consistently yielded poor results regardless of recipient age. Kidneys from adult donors gave the best results even in young recipients 0-5 years of age. With adult donor kidneys in cyclosporin-treated patients, high 1-year graft survival rates of 86 +/- 9% (SE) in 15 0- to 5-year-old recipients, 85 +/- 3% in 137 6- to 12-year-old recipients, and 83 +/- 1% in 6027 13- to 40-year-old recipients were observed.

Adolescent↗
PubMed1988

Probability of finding HLA-matched unrelated marrow donors.

Bone marrow transplantation has become the treatment of choice for certain hematologic diseases. However, only 30-40% of patients who might benefit from this procedure have a suitable family donor. Consequently, many centers have begun to explore the use of unrelated volunteer donors. Initial results have demonstrated the feasibility of this approach. As a result, a national effort has begun to recruit HLA-typed volunteers in order to establish a registry of individuals who would be willing to serve as bone marrow donors. This manuscript explores the potential impact of establishing such a registry. We find that a registry of attainable size could more than double the number of marrow transplants now being performed. However, even with a registry of enormous size, it will still not be possible to identify an HLA-matched donor for some patients.

Bone Marrow Transplantation↗
PubMed1988

Induction of a suppressive serum factor, prevention of sensitization, and prolongation of kidney graft survival in rats by transfusion with antibody-coated blood cells.

Transfusion with antibody-coated allogeneic blood cells suppresses the cytotoxic antidonor antibody response in a strongly incompatible rat combination (BN----LEW). Cell coating with homologous recipient antidonor antiserum, rat monoclonal antibodies against MHC class I donor antigens, or rabbit antirat lymphocyte serum all were effective. The suppression was not abrogated by repeated booster transfusions with untreated donor blood. Moreover, the suppression extended to antibody-uncoated antigens present on the same donor cell. Not only the antibody response but also the Graft-versus-host reaction against donor antigens was suppressed. The serum of pretreated animals contained suppressive activity. It suppressed the cytotoxic antibody response as well as the cellular immune response (GVH) when transferred into syngeneic recipients. A weaker suppression of antibody response was obtained by transferring spleen cells of pretreated animals into syngeneic recipients. The transfer data suggest that broadly reactive serum factor(s) were mainly responsible for the suppressive effect. Transfusion with LEW-anti-BN-coated donor cells before transplantation induced markedly prolonged kidney graft survival in the BN----LEW combination without additional immunosuppression (untreated controls: 8.4 +/- 0.4, pretreated recipients: 124 +/- 36 days, P less than 10(-4)).

Animals↗
PubMed1988

Correlation of in vitro immune defects with impaired gamma interferon response in human-immunodeficiency-virus-infected individuals.

65 patients belonging to known acquired-immune-deficiency-syndrome (AIDS) risk groups were tested for mitogen responsiveness to pokeweed mitogen, concanavalin A and phytohemagglutinin, percentages of peripheral blood CD4, CD8 and Leu7 lymphocyte subsets, serum neopterin levels, and gamma-interferon (gamma-IFN) concentrations in cell culture supernatants. Patients with clinical symptoms of human-immunodeficiency-virus infection showed reduced gamma-IFN production in vitro. The IFN concentrations were correlated significantly with mitogen-induced blastogenesis. High serum neopterin levels and decreased CD4/CD8 ratios were associated with diminished gamma-IFN levels. The percentage of Leu7 lymphocytes was increased in a group of patients with strikingly elevated gamma-IFN levels.

Acquired Immunodeficiency Syndrome↗
PubMed1988

Organ allocation.

Explore the source record for details and available documents.

Altruism↗