Usefulness of the cytotoxic test for testing levels of diphtheria antibodies in sera of immunized animals

: Vero cells method was used for determination of antibodies level in humans vaccinated with Td vaccine and also in animals immunized with Di, DiTe, Td and DTP vaccines. We have found quite high levels of antibodies in both groups of animals. There was also a significant increase of antibody level in the human sera after Td booster dose in the CCV and HA tests, but the correlation with antitoxin titre was low. CCV test could be useful for determination of immunogenicity of diphtheria toxid.