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Hepatitis B vaccination failure has been linked to the presence of certain human leukocyte antigen class II alleles. However, the functional background of these associations has remained unclear. Complement component C 4 is encoded within the major histocompatibility complex and is essential for classical pathway activation.Healthy individuals (n=4269) were vaccinated in a prospective trial with Engerix B. Nonresponse was classified as anti-HBs10 U/l after the last vaccination. Seventy-three nonresponders (NR) (1.7%) were identified. For comparison 53 responders (R) (anti-HBs10 IU/l) were drawn randomly from the same cohort. C4 allotyping was carried out by high-voltage agarose gel electrophoresis and C4alpha-chain typing using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. C4 gene deletions (C4Del) were studied by Southern blot.C4AQ0 alleles were observed in 45/73 (62%) NR compared to 17/53 (32%) R (P=0.001). C4ADel was observed in 24/73 (33%) NR and in 6/52 (12%) R (P=0.006). C4AQO alleles were present in 21/49 (43%) NR without C4Del compared to 10/46 (22%) in R without C4Del (P=0.031). In a logistic regression with DRB1*0301, DRB1*07, DRB1*1301 and C4AQ0 all except for DRB1*0301 showed a significant association.C4AQ0 shows a DRB1*0301 independent association with vaccine failure. C4AQ0 alleles probably contribute to inefficient complement activation and failure of B cells to secrete anti-HBs.

For mass cultivation of Candida albicans (serotype A), a fermenter dialysis culture technique is described and compared with shaking culture and fermenter batch culture techniques. Important growth parameters such as yeast dry weight and viable cell counts demonstrate the advantage of the fermenter dialysis culture. Mannan, the major antigen from Candida albicans prepared by phenol-water extraction followed by gel chromatography was tested with the monoclonal IgM antibody H5.

Nonresponsiveness to HBsAg vaccination is observed in 5-10% of vaccine recipients and is possibly caused by a defect in the T helper cell compartment. The immune response to HBsAg is influenced by genes of the major histocompatibility complex. We have investigated MHC class I and class II antigens in 53 adult responders and 73 nonresponders. Results obtained in this first study were tested in a second study with 56 responders and 62 nonresponders from an infant vaccination trial. In addition, the peripheral Vbeta-chain T-cell receptor repertoire was investigated using monoclonal antibodies and flow-cytometry in 26 adult responders and 38 nonresponders. As previously reported, nonresponsiveness to HBsAg vaccination was associated with DRB1*3 and DRB1*7. In addition, DRB1*13 was significantly increased among vaccine responders (35.2% vs 5.4%;p0.0001) suggesting an immune response promoting effect for this allele whereas the closely related allele DRB1*14 was associated with nonresponse in the infant study. There was no evidence for a hole in the T cell receptor Vbeta repertoire. In conclusion, in agreement with results obtained in mice there appears to be a hierarchy of DRB1* genes in the HBsAg immune response. The possible differential association of DRB1*13 and DRB1*14 may allow the identification of differences between responsiveness and nonresponsiveness to a few amino acid differences in the beta1-domain of the class II heterodimer.

Three human and three murine monoclonal antibodies were tested for their reactivity to tetanus toxin and toxoid and used to establish an enzyme immunoassay specific for tetanus toxin. The dissociation constants of the monoclonal antibodies were between 3.91 x 10(-9) and 8.48 x 10(-12). Two human monoclonal antibodies recognized conformation determinants on the toxin, whereas the others reacted to the heavy chain. Only a combination of antibodies of the two species allowed the development of an enzyme immunoassay for the detection of tetanus toxin with a lower detection limit of 1.2 micrograms/l.

Before screening monoclonal antibodies using enzyme immuno assays, it is necessary to prove that the coating of the solid phases occurs efficiently. The adhesion of whole cells of group B streptococci, Escherichia coli K1, Haemophilus influenzae type b and Candida albicans as well as B-Streptococcus group antigen, H. influenzae type b capsular antigen, and C. albicans cell wall antigen to polystyrene solid phases was studied and detected by the following methods:. Peroxidase competition procedure, scintillations measurement of 32phosphate-labelled germs, and reactions with monoclonal antibodies.

The group specific polysaccharide of Group B streptococci was isolated either by means of phenol-water extraction or by Lancefield extraction procedures. Two groups of rabbits were immunized with these substances to induce polyclonal antibodies. The phenol-water extract induced antisera had a significantly higher titer against B streptococci than against A-, D- and G streptococci in the agglutination reaction. The B-specific titers in rabbits immunized with phenol-water extract were significantly higher than those obtained in the rabbits immunized with Lancefield extract. In counter immunoelectrophoresis, only the antisera prepared by immunization with phenol-water extract reacted with standard antigen from group B streptococci. The serological specificity of the phenol-water extract antigen isolated from B streptococci was confirmed by counterimmunoelectrophoresis. The antigen was a heterologous fraction with a molecular mass of 8 x 10(4)-2 x 10(6) Dalton.