IMMUNOGENICITY OF COXIELLA-BURNETII WHOLE CELLS AND THEIR OUTER-MEMBRANE COMPONENTS

The immunogenicity and protective efficacy of the phase I and phase II Coxiella burnetii whole cells (Cb I and Cb II) and their outer membra ne components (OMC), i.e. phase I trichloroacetic acid extract (TCAE), phase I 29 K protein (PRO), phase I and II lipopolysaccharides (LPS I , LPS II), polysaccharides (PS I, PS II), and lipid A (LA I, LA II), w ere compared. The highest immune response was observed in BALB/c mice by Cb I in both humoral immunity and lymphocyte transformation assays, and in the protective effect as well. The immune response was also si gnificant by Cb II, but their protective capacity was low. The OMC rea cted variously. Only TCAE and PRO gave a high value of humoral immunit y evaluated by the serological methods. All OMC reacted in the haemoly tic plaque assay giving different responses. Lymphoproliferation of sp lenocytes was positive with all OMC using both Cb I and Cb II antigens with the exception of PS I and PS II in the case of Cb II antigen. Th e induction of protection against infectious Cb I was demonstrated aft er immunization with TCAE, PRO, and LPS I. Other OMC did not induce pr otection against this agent.