Ersatz von Tierversuchen bei der Wirksamkeitspruefung von Clostridien-Immunpraeparaten. Teilprojekt 3: Ersatzmethoden zur Pruefung von Rauschbrand-Impfstoffen (C.chauvoei) fuer Tiere Abschlussbericht

According to the German and European Pharmacopeia the quality control of blackleg vaccine is a challenge test done in guinea pigs. The challenge test includes, that vaccinated animals survive an artificial infection, while the control animals die with symptoms of a blackleg infection. The aim of the project 0310623 was to develop and standardize an in vitro method as an alternative to the challenge test in guinea pigs. In a first prevalidation study the in vitro method has to be tested of its suitability as an alternative method. A Double-Sandwich-ELISA was developed, based upon the verification of cellular and flagella antigens of C.chauvoei by determination of the antibodies in sera from guinea pigs, rabbits and sheep. Subsequent to the prevalidation study a 'standard operating procedure - SOP' for each species was reported. In all sera of the three animal species C.chauvoei antibodies were detected. Rabbit sera show a far lower antibody titer than guinea pig- and sheep sera. The results of the studies have shown, that the antigenetic variability of C.chauvoei hinders the usage of one special antigen for the control of all of the vaccines. The correlation between ELISA and animal test depends on the antigenetic homogeneity of the control- and vaccine strain. A differentiation between vaccines, which passed the animal challenge test and those which failed the animal challenge test is not possible up to now. The ELISA can replace the challenge test only in case of a validation between the in-vitro method and the animal test for each vaccine strain. Rabbits, which are used as a test animal for the quality control of all the other Clostridial vaccines, are not able to replace the guinea pig for serum production, which is needed for the ELISA test. It has to be mentioned, that no international standards of C.chauvoei antigen and antisera are available. It has to be clarified, if and how they can be produced. (orig.)SIGLEAvailable from TIB Hannover: F98B1216+a / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman