Antibody levels to outer surface proteins C and F (OspC and OspF， respectively) in sera collected from laboratory Beagle dogs at 1， 2， and 4 months after challenge with infected black-legged ticks (Ixodes scapularis) were determined. Each dog was confirmed by culture to harbor Borrelia burgdorferi in the skin (n = 10) or the skin and joints (n = 14). Significant levels of immunoglobulin M (Ig)M or IgG anti-OspC antibodies were detected in single serum samples from only 3 (13%) dogs. Similarly， IgM anti-OspF antibodies were detected in only 1 (4%) serum sample collected from a dog with B. burgdorferi in the skin and joints. In contrast， 4 (29%) dogs with skin and joint infections produced IgG anti-OspF... More
Antibody levels to outer surface proteins C and F (OspC and OspF， respectively) in sera collected from laboratory Beagle dogs at 1， 2， and 4 months after challenge with infected black-legged ticks (Ixodes scapularis) were determined. Each dog was confirmed by culture to harbor Borrelia burgdorferi in the skin (n = 10) or the skin and joints (n = 14). Significant levels of immunoglobulin M (Ig)M or IgG anti-OspC antibodies were detected in single serum samples from only 3 (13%) dogs. Similarly， IgM anti-OspF antibodies were detected in only 1 (4%) serum sample collected from a dog with B. burgdorferi in the skin and joints. In contrast， 4 (29%) dogs with skin and joint infections produced IgG anti-OspF antibodies after 2 months， and the response expanded to include 2 (20%) dogs with skin infection and 4 additional dogs with skin and joint infections (overall sensitivity = 62%) after 4 months. The findings failed to support the utility of OspC-based antibody tests for diagnosing canine Lyme disease， but demonstrated that dogs with B. burgdorferi colonizing joint tissue most often produced significant levels of IgG anti-OspF antibodies. Therefore， additional studies to more thoroughly evaluate the clinical utility of OspF-based antibody tests are warranted.
