Characterization of trypsin extractable antigens of Leptospira interrogans serovars pomona, bataviae & L. biflexa serovar patoc.

Leptospira strains after treatment with trypsin released an antigen (Tx) which consisted of protein (4.2 mg/ml), carbohydrate (0.39 mg/ml) and hexosamine (0.025 mg/ml). Immunodiffusion, immunoelectrophoresis and indirect haemagglutination tests revealed serological cross reactions among the three strains used. Inhibition of microscopic agglutination reaction by the Tx antigen was observed in homologous system only. The antigen was partially sensitive to heat (80 degrees C for 10 min) as detected by immunodiffusion and microscopic agglutination inhibition. These data revealed the presence of serovar-specific and genus-specific antigens on Leptospira strains. It is suggested that this antigen could be useful in developing a serodiagnostic test for leptospirosis.