Nonspecific inhibition of encephalomyocarditis virus replication by a type Ii interferon released from unstimulated cells of Mycobacterium tuberculosis-sensitized mice
Pusateri, A.M.; Ewalt, L.C.; Lodmell, D.L.
Journal of Immunology 124(3): 1277-1283
1980
ISSN/ISBN: 0022-1767 PMID: 6244349 Document Number: 166921
Unstimulated peritoneal cells (PC) from mice sensitized with nonviable Mycobacterium tuberculosis in an oil-droplet emulsion inhibit encephalomyocarditis virus (EMCV) replication in mouse embryo fibroblast monolayers. Concentrations of mycobacteria ranging from 50 to 500 microgram elicit PC that inhibit EMCV replication greater than 99%. PC collected 2 to 6 weeks post-inoculation of mycobacteria are most effective (greater than 99% inhibition), although cells harvested from mice 7 through 10 weeks inhibit viral replication greater than 90%. Inhibition of replication is not detected unless PC are in contact with infected monolayers for a minimum of 8 to 10 hr; nonviable PC are not effective. Optimal inhibition occurs in cultures infected with a low multiplicity of EMCV that are incubated at 37 degrees C. Inhibition of replication is not due to pH changes or depletion of nutrients in cultures, adsorption and/or inactivation of EMCV by macrophages, or killing of monolayers by the PC. Inhibition of viral replication by the unstimulated PC appears to be due to an interferon that is similar but not identical to classical mouse Type II interferon.