Identification of Leptospira interrogans strains by monoclonal antibodies and genomic analysis.

A recombinant probe derived from a genomic library of serovar hardjo strain Hardjoprajitno, and a panel of serovar specific Monoclonal Antibodies (MAbs) were used for the characterization of 31 Leptospira isolates from cattle and swine. The two methods performed equally well in serovar identification except for the distinction of the genotypes hardjoprajitno and hardjobovis within serovar hardjo which could only be obtained by genomic analysis. The combination of immunological and genetic information was also useful to evaluate the degree of variability of Leptospira strains. The quality of the patterns and the sensitivity provided by a digoxigenin labelled probe were comparable to those obtained with a radioactive reagent.