Summary
Fraction IB (FIB) from Pasteurella pestis induced immediate protection of mice concomitantly infected with plague. Moreover, the serum withdrawn from mice 1 or 2 days after treatment with FIB passively protected mice against P. pestis. Both the serum β-globulin and leukocyte concentrations increased as protection increased during this time. Subsequently the concentrations of both β-globulin and leukocytes decreased. About 6 days after treatment there was a second period of increased resistance which was accompanied by an increase in serum γ-globulin. Leukocytosis was not accompanied by increased phagocytosis. An increase in β-globulin concentration was also induced by inoculating mice with protein from Escherichia coli, but these mice were not protected against plague. Either the β-globulin contained antibodies responsible for the early protection or the early increase in β-globulin was coincidental.
Footnotes
This work was sponsored by the Office of Naval Research and the Bureau of Medicine and Surgery, U. S. Navy, under the terms of a contract between the Office of Naval Research and the Regents of the University of California. Reproduction in whole or in part is permitted for any purposes of the United States Government.
