Evaluation of monoclonal antibodies with specificity for human IgA, IgA subclasses and allotypes and secretory component. Results of an IUIS/WHO collaborative study.

51 monoclonal antibodies (McAb) with putative specificity for human IgA, the IgA subclasses, Am allotypes or secretory component (SC) were evaluated for immunoreactivity and specificity by nine laboratories employing immunodiffusion, agglutination, immunohistological assays, immunoblotting and direct binding and competitive inhibition enzyme immunoassays. McAbs specific for IgA PAN (n = 24), IgA1 (n = 7), IgA2 (n = 3), IgA2m(2) (n = 2), non-IgA2m(2) (n = 4) and SC or secretory IgA (n = 5) were identified that were immunoreactive and specific in the assays employed. The McAbs identified as IgA- or SC-reactive were shown to be non-reactive to human IgG, IgM, IgD, IgE, kappa and lambda by direct binding and competitive inhibition immunoassays.

Evaluation of monoclonal antibodies having specificity for human IgG subclasses: results of the 2nd IUIS/WHO collaborative study.

Following the 1st IUIS/WHO Collaborative Study of monoclonal anti-IgG subclass antibodies, a panel of WHO Specificity Reference Reagents (SRR) was established [Jefferis, R., et al. (1985) Immunol.

Analysis of antibody profiles in children with whooping cough.

Development of antibody titres in non-vaccinated children with whooping cough of different duration (all confirmed by positive culture) were investigated by ELISA using lymphocytosis promoting factor (LPF, pertussis toxin), filamentous haemagglutinin (FHA), 69 kDa protein and lipopolysaccharide (LPS) as antigens. The antibody responses occur in three different patterns: Firstly, the LPF antibody response develops very quickly starting with the first day of clinical cough with all three classes, IgG, IgM and IgA appearing simultaneously; LPF antibody appears to be a dominant feature. Secondly, FHA and 69 kDa antibodies appear, starting as IgM with the shift to IgG and IgA later.

Evaluation of immunotherapy-induced changes in specific IgE, IgG and IgG subclasses in birch pollen allergic patients by means of immunoblotting. Correlation with clinical response.

Sera from 27 birch pollen-allergic patients who had undergone hyposensitization treatment for 22-41 months were studied by immunoblotting before and after therapy, whereby the levels of IgE, IgG and IgG1-4 antibodies directed against the major allergen Bet v I and minor allergens of birch pollen were monitored. The clinical benefit of immunotherapy (IT) was evaluated using a symptom specific questionnaire. In patients with good clinical response (responders, n = 18), as defined by improvement of symptoms, anti-Bet v I IgE antibodies were found to decrease in 10/18 patients (55.

Ontogeny of the humoral response to group A streptococcal carbohydrate: class and IgG subclass composition of antibodies in children.

We determined isotypes of natural antibodies to streptococcal group A carbohydrate (A-CHO) in sera from 101 children between 1 and 16 years of age, using a calibrated enzyme-linked immunosorbent assay system. Anti-A-CHO IgM could be detected in all but one sera. Median levels increased with age and were highest between 8 and 12 years.