Typing of serum-soluble HLA-B27 antigen by ELISA.

An ELISA using serum as soluble HLA antigen source was developed for HLA-B27 typing. Two sandwich assays were run in parallel. The first assay utilized a monoclonal antibody (mAb) reacting with a determinant expressed by both HLA-B7 and B27 antigens; the other assay utilized a mAb reactive with HLA-B7 antigens but not with HLA-B27 antigens. After incubation with serum samples, bound HLA antigen was detected using an anti-beta 2m antibody conjugated to peroxidase and a chromogenic substrate. Absorbance of each well was measured at 490 nm. Based on analysis of absorbances obtained with panels of specimens of known HLA phenotypes, a mathematical algorithm was developed to derive the specimen HLA-B27 phenotype from its ELISA absorbance values. Despite the lack of monospecific mAb, an accurate HLA-B27 typing was possible. 362 specimens (including 151 HLA-B27-positive) were tested. Agreement between microlymphocytotoxicity and ELISA was 99.2%. No correlation between the level of HLA-B27 antigen reactivity and the amount of total HLA class I antigen in serum was observed. This report demonstrates the possibility of using serum-soluble HLA antigen and ELISA technology for histocompatibility testing. The assay offers several significant advantages over microlymphocytotoxicity: no need for cell preparation, batch testing capabilities and objective, reproducible interpretation of results.

HLA-DR antigens in multiple sclerosis: two-dimensional gel electrophoresis.

Fifty to eighty percent of white patients with clinically definite MS express the DR2 antigen. In patients and normal controls who possess the DR2 antigens, analysis of the polymorphic light chain by two-dimensional polyacrylamide gel electrophoresis revealed no structural differences.

Segregation and mapping analysis of polymorphic HLA class I restriction fragments: detection of a novel fragment.

An HLA-B7 complementary DNA clone was used as a hybridization probe to analyze the segregation pattern of polymorphic class I restriction fragments in several families whose HLA types had been determined by serological techniques. In one family in which a crossover in the HLA region had occurred, a specific genomic fragment was mapped with respect to the crossover. In another family, a novel genomic fragment present in one child and absent in all other family members was observed. With the exception of this novel fragment, all polymorphic class I fragments observed in this study segregated with a serologically defined parental haplotype, a result consistent with HLA linkage.

Infections due to herpesviruses in cardiac transplant recipients: role of the donor heart and immunosuppressive therapy.

The role of the donor heart and immunosuppressive therapy on infection due to herpesviruses in 74 cardiac transplant recipients (CTRs) was determined. When cellular blood products from donors seronegative for antibody to cytomegalovirus (anti-CMV) were used, all primary CMV infections were attributable to transmission from donor heart. None of eight CTRs negative for anti-CMV before transplant and who received an anti-CMV donor heart and anti-CMV blood products developed CMV infection compared to one (20%) of five who received unscreened blood. A change from high-dosage anti-thymocyte globulin, azothioprine, and prednisone (ATG regimen) to low-dosage anti-thymocyte globulin, cyclosporin A, and prednisone (CsA regimen) significantly decreased the severity and prevalence of lesions due to herpes simplex virus and the duration of CMV shedding in patients with recurrent CMV infection. CTRs with recurrent CMV infection treated with the ATG regimen had significantly more fever, required more parenteral antibiotics, and were more likely to be infected with opportunistic pathogens than were CsA-treated patients.

Evaluation of a walking-donor blood transfusion program in an intensive care nursery.

A prospective study was carried out to identify the immediate and long-range advantages and disadvantages of a walking-donor transfusion program for an intensive care newborn nursery. The effect of heparin on coagulation of blood was evaluated and found to be minimal. There was no evidence of transmission of HBSAg. The prevalence of CMV infection at the time of follow-up was higher in infants who had received blood from donors seropositive for CMV than in infants who had been transfused from seronegative donors. In our experience, a walking-donor program has been a safe and effective method for the provision of small transfusions of blood to sick neonates.