NONSPECIFIC RESISTANCE TO TUBERCULOSIS

Abstract

It was found that methanol extracts of tubercle bacilli were capable of increasing the survival time of mice challenged with virulent tubercle bacilli. These extracts did not account for the total activity of lyophilized (living) suspensions. The tremendous difference in the protective activity of the lyophilized suspensions as compared with that of the extracts suggested that some substance(s) present in lyophilized cells were labile to methanol treatment. An alternate possibility (masking substances to account for the low protective activity of extracts) was excluded by an analysis of the quantitative distribution of fractions after chromatography of the crude extracts. Waxes C and D and Anderson''s purified wax were ineffective in protecting mice against tuberculosis, while lipopolysaccharides from Escherichia coli, Salmonella, and a methanol extract of E. coli proved as effective as methanol extracts and subtractions of tubercle bacilli. Mice treated with methanol extracts were able to resist, to a certain degree, infection by Klebslella pneumoniae, Diplococcus pneumoniae, and 2 strains of Salmonella.