Detection of antibodies to decorin-binding protein A (DbpA) and DbpB after infection of dogs with Borrelia burgdorferi by tick challenge.

We characterized the antibody response to decorin-binding protein A (DbpA) or DbpB from immune serum samples collected from 27 dogs infected with Borrelia burgdorferi by Ixodes scapularis ticks. Immunoglobulin M (IgM) antibodies to DbpA or DbpB were rarely detected, but high levels of IgG antibodies to DbpA were detected in 16 of 27 of the immune sera collected 1 mo after infection, 20 of 25 of the sera collected after 2 mo, and each of the 23, 17, or 11 serum samples evaluated after 3, 4, or 5 mo, respectively. In addition, IgG antibodies to DbpB were detected in 22 of 27 (p = 0.005) tested dogs after 1 mo, and the frequency of detecting the antibodies thereafter closely mimicked the antibody responses to DbpA. Moreover, antibodies to DbpA or DbpB were not produced by dogs vaccinated with a whole-cell B. burgdorferi bacterin; removing the antibodies to DbpA by adsorption to recombinant DbpA (rDbpA) did not affect the reactivity detected by a rDbpB ELISA. Therefore, the findings from our preliminary study showed that antigenically distinct antibodies to DbpA or DbpB are produced reliably during canine infection with B. burgdorferi, and the response is not confounded by vaccination with a Lyme disease bacterin. Larger studies are warranted to more critically evaluate whether detecting the antibody responses can improve serodiagnostic confirmation of canine Lyme disease.

Vaccination with the ospA- and ospB-Negative Borrelia burgdorferi Strain 50772 Provides Significant Protection against Canine Lyme Disease.

Beagles received placebo or ospA- and ospB-negative Borrelia burgdorferi before a tick challenge. A total of 28 (41%) ticks and skin biopsy specimens from each control dog (n = 10) contained B. burgdorferi. In contrast, 12 (19%) ticks recovered from the vaccine recipients (n = 10) were infected (P = 0.0077), and 5 dogs yielded spirochetes from the skin biopsy specimens (P = 0.0325). In addition, 9 (90%) placebo recipients and 4 (40%) vaccine recipients developed joint abnormalities (P = 0.0573). Therefore, vaccination with the ospA- and ospB-negative spirochete provided significant protection against Lyme disease.

One-year duration of immunity induced by vaccination with a canine Lyme disease bacterin.

Laboratory-reared beagles were vaccinated with a placebo or a bacterin comprised of Borrelia burgdorferi S-1-10 and ospA-negative/ospB-negative B. burgdorferi 50772 and challenged after 1 year with B. burgdorferi-infected Ixodes scapularis ticks. For the placebo recipients, spirochetes were recovered from 9 (60%) skin biopsy specimens collected after 1 month, and the organisms persisted in the skin thereafter. Ten (67%) dogs also developed joint infection (3 dogs), lameness or synovitis (7 dogs), or B. burgdorferi-specific antibodies (8 dogs). For the vaccine recipients, spirochetes were recovered from 6 (40%) skin biopsy specimens collected after 1 month. However, subsequent biopsy specimens were negative, and the dogs failed to develop joint infection (P = 0.224), lameness/synovitis (P = 0.006), or Lyme disease-specific antibody responses (P = 0.002). The bacterin provided a high level of protection for 1 year after immunization, and the addition of the OspC-producing B. burgdorferi 50772 provided enhanced protection.

Bacterin that induces anti-OspA and anti-OspC borreliacidal antibodies provides a high level of protection against canine Lyme disease.

Groups of 15 laboratory-bred beagles were vaccinated and boosted with either a placebo or adjuvanted bivalent bacterin comprised of a traditional Borrelia burgdorferi strain and a unique ospA- and ospB-negative B. burgdorferi strain that expressed high levels of OspC and then challenged with B. burgdorferi-infected Ixodes scapularis ticks. The vaccinated dogs produced high titers of anti-OspA and anti-OspC borreliacidal antibodies, including borreliacidal antibodies specific for an epitope within the last seven amino acids at the OspC carboxy terminus (termed OspC7) that was conserved among pathogenic Borrelia genospecies. In addition, spirochetes were eliminated from the infected ticks that fed on the bacterin recipients, B. burgdorferi was not isolated from the skin or joints, and antibody responses associated specifically with canine infection with B. burgdorferi were not produced. In contrast, B. burgdorferi was recovered from engorged ticks that fed on 13 (87%) placebo-vaccinated dogs (P<0.0001), skin biopsy specimens from 14 (93%) dogs (P<0.0001), and joint tissue specimens from 8 (53%) dogs (P=0.0022). In addition, 14 (93%) dogs developed specific antibody responses against B. burgdorferi proteins, including 11 (73%) with C6 peptide antibodies (P<0.0001). Moreover, 10 (67%) dogs developed Lyme disease-associated joint abnormalities (P<0.0001), including 4 (27%) dogs that developed joint stiffness or lameness and 6 (40%) that developed chronic joint inflammation (synovitis). The results therefore confirmed that the bacterin provided a high level of protection against Lyme disease shortly after immunization.