Protein and antigenic analysis of Borrelia burgdorferi isolated in northern Italy: computerized analysis of phenotypic characteristics.

Four Borrelia burgdorferi strains isolated in the same restricted geographic area share different protein patterns on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The use of polyclonal rabbit antisera and a battery of monoclonal antibodies directed toward the immunodominant proteins OspA, OspB, and pC also revealed different epitope distributions and specificities of these antigens on the strains examined. For the first time, a computerized analysis of these phenotypic characters was done mainly by cluster analysis. The computerized analysis revealed the levels of similarities among the strains and indicated, on a quantitative basis, that one of them is much closer to the American strain B31 than to the other strains.