Chronic kidney disease is considered to be most common in geriatric domestic cats. It has been reported that the feline viral rhinotracheitis, calicivirus, and panleukopenia (FVRCP) vaccine prepared from the Crandell-Rees feline kidney (CRFK) cell line can induce cross-reactions of antibodies with feline kidney tissues. As an anti-cat kidney antibody was not available commercially for this study of autoantibody in cats, the purpose of this study was to produce anti-cat kidney antibody in rabbits for further study of autoantibody in cats after FVRCP vaccination. Kidney proteins from cadaveric cats were extracted and immunized into rabbits using Montanide as the adjuvant. Based on enzyme-linked immunosorbent assay measurement, all immunized rabbits produced high levels of anti-cat kidney antibodies and some began to produce antibodies as early as 2 weeks after immunization. Immunofluorescence staining of rabbit sera showed kidney-bound antibodies in glomerulus, Bowman's capsule, apical surface of the proximal convoluted tubule, peritubular surface, and interstitial cells. Western blot analysis of cat kidney proteins revealed molecular weights (M.W.) of 72, 55, 47, and 31 kDa, while binding to the CRFK cell proteins was observed at M.W. of 43 and 26 kDa. The antibody that recognized the 47 kDa protein was similarly detected in cats with autoantibody presence after FVRCP vaccination. The kidney-bound antibody profile at different time points and its patterns in rabbits could be used as a model for the study of autoantibody to cat kidney in feline chronic kidney diseases.
Animals ; Antibodies ; Blotting, Western ; Bowman Capsule ; Cadaver ; Cats ; Cell Line ; Enzyme-Linked Immunosorbent Assay ; Fluorescent Antibody Technique ; Immunization ; Kidney ; Molecular Weight ; Rabbits ; Renal Insufficiency, Chronic ; Vaccination ; Vaccines

Background: The feline viral rhinotracheitis, calicivirus, and panleukopenia (FVRCP) vaccine, prepared from viruses grown in the Crandell-Rees feline kidney cell line, can induce antibodies to cross-react with feline kidney tissues. Objectives: This study surveyed the prevalence of autoantibodies to feline kidney tissues and their association with the frequency of FVRCP vaccination. Methods: Serum samples and kidneys were collected from 156 live and 26 cadaveric cats.Antibodies that bind to kidney tissues and antibodies to the FVRCP antigen were determined by enzyme-linked immunosorbent assay (ELISA), and kidney-bound antibody patterns were investigated by examining immunofluorescence. Proteins recognized by antibodies were identified by Western blot analysis. Results: The prevalences of autoantibodies that bind to kidney tissues in cats were 41% and 13% by ELISA and immunofluorescence, respectively. Kidney-bound antibodies were observed at interstitial cells, apical border, and cytoplasm of proximal and distal tubules; the antibodies were bound to proteins with molecular weights of 40, 47, 38, and 20 kDa. There was no direct link between vaccination and anti-kidney antibodies, but positive antibodies to kidney tissues were significantly associated with the anti-FVRCP antibody. The odds ratio or association in finding the autoantibody in cats with the antibody to FVRCP was 2.8 times higher than that in cats without the antibody to FVRCP. Conclusions These preliminary results demonstrate an association between anti-FVRCP and anti-cat kidney tissues. However, an increase in the risk of inducing kidney-bound antibodies by repeat vaccinations could not be shown directly. It will be interesting to expand the sample size and follow-up on whether these autoantibodies can lead to kidney function impairment.

Background: The feline viral rhinotracheitis, calicivirus, and panleukopenia (FVRCP) vaccine, prepared from viruses grown in the Crandell-Rees feline kidney cell line, can induce antibodies to cross-react with feline kidney tissues. Objectives: This study surveyed the prevalence of autoantibodies to feline kidney tissues and their association with the frequency of FVRCP vaccination. Methods: Serum samples and kidneys were collected from 156 live and 26 cadaveric cats.Antibodies that bind to kidney tissues and antibodies to the FVRCP antigen were determined by enzyme-linked immunosorbent assay (ELISA), and kidney-bound antibody patterns were investigated by examining immunofluorescence. Proteins recognized by antibodies were identified by Western blot analysis. Results: The prevalences of autoantibodies that bind to kidney tissues in cats were 41% and 13% by ELISA and immunofluorescence, respectively. Kidney-bound antibodies were observed at interstitial cells, apical border, and cytoplasm of proximal and distal tubules; the antibodies were bound to proteins with molecular weights of 40, 47, 38, and 20 kDa. There was no direct link between vaccination and anti-kidney antibodies, but positive antibodies to kidney tissues were significantly associated with the anti-FVRCP antibody. The odds ratio or association in finding the autoantibody in cats with the antibody to FVRCP was 2.8 times higher than that in cats without the antibody to FVRCP. Conclusions These preliminary results demonstrate an association between anti-FVRCP and anti-cat kidney tissues. However, an increase in the risk of inducing kidney-bound antibodies by repeat vaccinations could not be shown directly. It will be interesting to expand the sample size and follow-up on whether these autoantibodies can lead to kidney function impairment.