Restriction Endonuclease DNA Analysis of Antigenic Variants of Leptospires Selected by Monoclonal Antibodies

The genome of antigenic variant CV (CT3)-1 derived from Leptospira inter rogans serovar canicola was compared by cleavage with restriction endonucleases with the parent and serovar bafani,to which the variant was serologically most closely related. No differences were observed between the parent and variant in DNA re strictionendonuclease patterns using eight restriction endonucleases. Serovar was different in the patterns from the parent and antigenic variant CV(CT3)-1. The two antigenic variants derived from serovar hebdomadis, HV(H16)-1 and HV(H19)-1 which belonged serologically to serovars jules and hebdomadis,respectively, were comparedby restriction endonuclease DNA analysis with the parent and serovar jules. No differences were observed between the parent and variants in DNA restriction endonuclease patterns using the same enzymes. But some differences were observed in DNA restriction endonuclease patterns between HV(H16)-1 and serovar jules. Thus, the antigenic variant selected from the parent by the anti-parent monoclonal antibody andserologically different from the parent, being identified either as a new serovar or as a known one, was found to be similar to the parent by the restriction endonuclease DNA analysis.