Markers of cell-mediated immunity after vaccination with an inactivated, whole-cell Q fever vaccine.
A clinical trial of Q fever vaccine in four South Australian abattoirs showed apparently complete protection against natural infection; however, only 50%-60% of vaccinees developed complement-fixing or immunofluorescent antibody after vaccination. Cell-mediated immunity to Coxiella burnetii antigens, as measured by an index of lymphoproliferative responses (LSI) of peripheral blood mononuclear cells, was therefore assessed. Eighty-five percent of 13 subjects with "low risk" of exposure to Q fever and with an initially negative LSI converted to a positive LSI after vaccination; conversion was noted nine to 13 days after vaccination, and positive values were obtained for at least 96 d. Only 35% of this group seroconverted. In a "high-risk" group (abattoir workers), higher rates of positive LSI (greater than 95%) and of antibody (50%-70%) were observed after vaccination; greater than 95% of vaccinees in this group, who had been vaccinated five years previously, had positive LSI values.
Izzo
A A
AA
Department of Pathology, University of Adelaide, Australia.
Marmion
B P
BP
Worswick
D A
DA
D000942:Antigens, Bacterial / Q000276:immunology; D001428:Bacterial Vaccines / Q000276:immunology*; D003381:Coxiella / Q000276:immunology*; D004306:Dose-Response Relationship, Immunologic; D006801:Humans; D007111:Immunity, Cellular; D066298:In Vitro Techniques; D008213:Lymphocyte Activation; D011778:Q Fever / Q000276:immunology / Q000517:prevention & control*; D012307:Risk Factors; D013997:Time Factors; D014611:Vaccination
D000942:Antigens, Bacterial; D001428:Bacterial Vaccines