Application of two in vitro methods for the toxicity test of autogenous vaccines

According to the 3Rs principle (Replacement, Refinement, Reduction), this study aims to find alternative methods to evaluate the toxicity of autogenous vaccines. Currently in Italy the Istituti Zooprofilattici Sperimentali (II.ZZ.SS.) must perform the in vivo toxicity test for each lot of autogenous vaccine produced as laid down in the Decree of 17 March 1994. This paper describes two in vitro methods for assessing the toxicity of autogenous vaccines. The first is the MTT test based on the metabolic reaction of tetrazolium salt in vital cells. The second method is the test for measurement of IL-1ß production by macrophages, obtained after in vitro differentiation from pig monocytes in peripheral blood mononuclear cells. The two tests were performed on different vaccine antigens dilution: 1:20, 1:100 and 1:500. The results show a positive tendency between the two methods pointing out the potential of these methodologies combined for the replacement of the current in vivo test.