Distribution of immunoglobulin G (IgG) and A (IgA) subclasses following Q fever vaccination with soluble phase I Coxiella burnetii extract

High levels of IgG1, IgG3 and IgA2 antibodies have been observed in patient s with Q fever following Coxiella burnetii infection. This IgG subclass dis tribution is more typical of viral and autoimmune diseases than of bacteria l infections. It seemed, therefore, of interest to carry out a prospective study of the distribution of immunoglobulin subclasses after vaccination wi th phase I C. burnetii tricloroacetic soluble extracts to detect possible d ifferences with respect to natural infection. The antibody response found i n vaccinees was mainly restricted to the IgG1, IgG2 and IgA1 subclasses. Th ese findings confirm differences in isotype distribution when compared to t hose of patients with acute or chronic Coxiella infections and opens an are a of interest with respect to the role of IgA subclasses. (C) 2000 Elsevier Science Ltd. All rights reserved.