Determination of Mycoplasma pneumoniae antibody titer in human sera by enzume-linked immunosorbent assay : I. examination of basic condetions

A method of an enzyme-linked immunosorbant assay (ELISA) was developed for detection of Mycoplasma pneumonisa (Mpn) antibody titers. 1. The optimal concentration of the wole cell antigen (62.5μg/ml) and the optimal dilution rati od serum samples(1 : 100) were determined. 2. Treatment of solid phase with BSA after antigen coating and addition of BSA to dilution buffers for serum samples and for enzyme-conjugated sera were effective to eliminate non-specific reactions. 3. Covering microplates with plastic film or placing them in a humid bos was effective to prevent ”edge-effects2 during incubation. 4. Sera from patients with Mpn infection as well as those with other infections contained LgM-RF (rheumatoid factor) detectable by ELISA for anti-Mpn IGM. To eliminate the false psditive reaction, removal of igM-RF in serum samples is necessary prior to IgM antibody determination. 5. The ELISA titers determined by a single serum dilution were well correlated with those determined by the serial dilution method. 6. ELISA by a single dilution method may be useful for estimating antibody titers of a large number of samples for seroepidemiological survey.