Influence of Challenge Strain on Potency of Pertussis Vaccines in Mice

Abstract

Eldering, Holwerda and Baker¹ have recently shown that, in mouse-protection tests with pertussis vaccines, the species-specific agglutinogen (factor 1) is more important than the type-specific agglutinogens (factors 2 and 3). This confirms my own findings² and those of Andersen and Bentzon³ with actively immunized mice, and emphasizes the limitation of the standard mouse-protection test in assessing the prophylactic potency of pertussis vaccines⁴. It is not, however, incompatible with the demonstration of type-specific immunity in mice by passive protection with mono-specific sera and subsequent challenge with selected strains of various different serological types^4,5. It does not, moreover, disprove the importance of factors 2 and 3 in human prophylaxis against strains of Bordetella pertussis which occur naturally^6–10.