Abstract
Macrophage inhibitory factor-A3 (MIF-A3), a fraction derived from
Mycobacterium avium serovar 2 inhibited candidacidal activity in macrophages from
C57BL
6
,
C57BL
10
,
C3H
HeJ
and
A
J
strains of mice. Inhibition of candidacidal activity was demonstrated at MIF-A3 concentrations ranging from 100–400 μg/ml in macrophages without additional stimulators (exception
C3H
HeJ
macrophages) and in macrophages additionally stimulated with 200 U/ml interferon-γ, 100 ng/ml phorbol myristate acetate and 0.4 ng/ml
E. coli lipopolysaccharide from all mouse strains tested. The decreased candidacidal effect produced by MIF-A3 was dose-dependent and appeared greatest in macrophages treated with phorbol myristate acetate and lipopolysaccharide. This effect was neutralized by the addition of goat anti-MIF-A3 antiserum. Macrophages from the
Bcg
s
mouse strains (
C57BL
6
and
C57BL
10
) were more sensitive to the effect(s) of MIF-A3 than macrophages from the
Bcg
r
mouse strains (
C3H
HeJ
and
A
J
).
