Mycobacterial antibodies after tuberculin testing, BCG- vaccination, BCG-immunotherapy and against cross-reacting antigens in a solid-phase radioimmunoassay.

A solid-phase radioimmunoassay (SPRIA) was used to investigate several factors influencing false positive and negative results in serodiagnostic test for tuberculosis, Unheated cytoplasmic fractions of mycobacteria, and other microorganisms were bound to polystyrol and antibody binding of sera from tuberculous, non tuberculous hospitalized patients and healthy adults was tested by the SPRIA-method. The level of antibody concentration in the SPRIA reflects roughly cross-reactivity between the antigens. Similar antibody binding occurred with M. tuberculosis, M. bovis, M. ulcerans and several "atyical" mycobacteria as test antigens, while other mycobacterial species and one of two tested tuberculin preparation (PPD) showed less antibody binding capacity. Significant cross-reactivity of fourty to sixty per cent was found between M. tuberculosis and N. asteroides but no cross-reaction was observed with C. parvum, S. typhi, S. paratyphi, C. Albicans or Aspergillus niger. Heating of mycobacterial cytoplasmic antigen resulted in a decrease of the test specifity. Tuberculin testing and intracutaneous BCG-vaccination in healthy adults had no distinct influence on the antibody response against several mycobacterial test antigens. However, a rapid increase of antibody levels was documented in melanoma patients after BCG-immunotherapy by sacrification with a more concentrated vaccine.