Two batches each of
diphtheria-tetanus-acellular pertussis vaccine (DTaP) and that combined with inactivated
polio vaccine purchased from foreign markets were tested by mouse
body weight decreasing (BWD) toxicity test and Limulus amaebocyte lysate (LAL) test. Three out of the four imported
vaccine batches showed the levels of BWD toxicity even comparable to that of DT-whole cell
pertussis vaccine. BWD toxicity test is based on
endotoxin dose-dependent
weight loss of mice and has been used for controlling
endotoxin in DTaP. Although of the strong BWD toxicity of the imported
vaccines, there was no marked difference in LAL test results between the imported
vaccines and Japanese DTaP. However, one imported DTaP batch showed very strong interference with LAL activity of spiked
lipopolysaccharide (LPS). The batch interfered not only with LAL activity but also with pyrogenicity and
prostaglandin E(2) induction activity. However, the pyrogenicity of the spiked LPS could be recovered from the precipitated fraction of the batch by treating with
phosphate buffer to suggest the possibility of recovering in vivo toxicity. As an adequate in vitro test method could not be identified for controlling the safety of the interfering batch, an appropriate in vivo test would be required for testing such
vaccines.