Use of monoclonal antibodies in an enzyme-linked inhibition assay for rapid detection of streptococcal antigen.

We have developed an enzyme-linked monoclonal antibody inhibition assay to detect bacterial antigens in cerebrospinal fluid. The monoclonal antibody used in this immunodiagnostic test was produced by continuous cultures of hybrid myeloma cell lines. Using this assay, type III GBS antigen was detected in CSF specimens from 11 culture-proven cases of GBS meningitis and in the knee aspirate from an infant with GBS septic arthritis. Five spinal fluid specimens from meningitis due to other bacterial pathogens and ten other control samples were negative. The ELMIA detected streptococcal antigen at a concentration of 10 ng/ml, and is more sensitive and specific than currently used immunodiagnostic tests.