Lysosomes and the "toxicity" of Rickettsials. III. Response of L cells infected with egg-attenuated C. psittaci 6BC strain

Abstract

During the infection of L cells (clone 60 and 929) with egg-grown C. psittaci 6BC strain, lyosomes retained their integrity and L cells were not injured. Infected cells proliferated more intensely and showed higher mitotic indices from 24 h post infection than noninfected control cells. Chlamydial inclusions were released from the cytoplasm of infected L cells by pseudopodia-like extrusions. These events were in marked contrast to the effect of the L cell grown C. psittaci 6BC strain which caused activation of lysosomal acid phosphatase and damage of L cells. Previous comparative studies of the host lysosomal response to egg-grown as compared to cell culture grown C. psittaci 6BC strain in cultured macrophages and L cells are discussed.