Identity of the filterable hemolytic anemia agent of Sacks with Haemobartonella muris.

Moore, D. H. (The Rockefeller University, New York, N. Y.), R. N. Arison, H. Tanaka, W. T. Hall, and M. Chanowitz. Identity of the filterable hemolytic anemia agent of Sacks with Haemobartonella muris. J. Bacteriol. 90:1669-1674. 1965.-In 1960 a new hemolytic agent in rats was reported. It was thought to be a filterable, nonsedimentable, replicating infectious agent, different from Haemobartonella muris. Rats which recovered from the infection developed a resistance to several kinds of transplantable tumors. It is here shown that this agent has the same properties as those reported in the literature and reconfirmed by us for H. muris. The size of the agent is approximately 500 mmu as determined by correlating bioactivity with Gradocol membrane filtrates and fractions from a diffusion cell, and its density is about midway between that of whole serum and distilled water (approximately 1.020) as determined by the sedimentation of bioactivity in an ultracentrifuge. Diffusion at 30 C indicated a lack of motility by the agent bodies. Rats were found to be protected against infection with the agent by daily administration of chlortetracycline and by prior infection with H. muris. The agent bodies were indistinguishable from H. muris in both the light and the electron microscope.