[Detection of antibodies against Pasteurella multocida toxin with a cell culture method and an enzyme immunoassay]
Pasteurella multocida toxoid is the most important antigen in vaccines against progressive atrophic rhinitis in pigs. Testing antibodies against Pasteurella multocida toxin in a cell culture neutralisation assay on embryonic bovine lung cells and a modified, commercially available enzyme-linked immunosorbent assay (DAKO, Denmark) is sensitive and gives good reproducible results. Determination of antitoxin antibodies in swine and guinea pigs simultaneously in both methods resulted in good coefficients of correlation (r = 0.88 and 0.93). Induction of antibodies to Pasteurella multocida toxin by thirty batches of ten toxoid containing vaccines was tested by subcutaneous application of one fifth pigdose (0.4-1 ml) twice in intervals of three weeks. The animals showed neither signs if illness nor significant local or systemic reactions. Three weeks after the second immunisation 25 batches induced titres being at least 2 log2 dilutions higher than a parallel titrated reference serum (mean titre of reference serum was 1:23.26</superior). Five batches belonging to one vaccine induced no detectable antibodies to the toxin. Additional testing of two negative and one positive batch of this vaccine in the target species by immunising them twice according to the manufacturers scheme, gave identical results. Therefore it is concluded that immunisation of guinea pigs and determination of humoural immune response in vitro, is a potent and ethical justifiable method to judge the quality of the Pasteurella multocida toxoid component of vaccines against progressive atrophic rhinitis in pigs.
Öppling
Volker
Paul-Ehrlich-Institut, Abteilung Veterinärmedizin, D-Langen.
Kusch
Manuela
M
Rübmann
Petra
P
Cussler
Klaus
K