Premium
Natural Killer Cell Activity and Macrophage‐Dependent Inhibition of Growth or Killing of Mycobacterium avium Complex in a Mouse Model
Author(s) -
Bermudez Luiz Eduardo M.,
Kolonoski Peter,
Young Lowell S.
Publication year - 1990
Publication title -
journal of leukocyte biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.819
H-Index - 191
eISSN - 1938-3673
pISSN - 0741-5400
DOI - 10.1002/jlb.47.2.135
Subject(s) - biology , intracellular , intracellular parasite , macrophage , microbiology and biotechnology , interleukin 12 , in vitro , immunology , cytotoxic t cell , biochemistry
Natural killer (NK) cells from spleens of normal and Mycobacterium avium complex (MAC)‐infected C57 black mice (C57 BL/6 bg/+) were examined for their capacity to activate splenic and peritoneal macrophages from beige mice to inhibit or kill intracellular MAC. Peritoneal and splenic macrophages from beige mice were exposed in vitro to NK cells obtained from MAC‐infected and uninfected black mice. NK cells from uninfected black mice were also treated in vitro with recombinant interleukin‐2 (IL‐2) for 48 h before incubation with macrophages. While control macrophages supported intracellular growth of MAC, macrophages exposed to unactivated NK cells inhibited growth of the intracellular bacteria, as determined 4 days after infection. IL‐2 stimulated NK cells, and NK cells obtained from MAC‐infected animals were able to activate murine macrophages in vitro to inhibit growth or kill 40.0 ± 5% and 61.3 ± 6% of the intracellular bacteria, respectively. In other experiments, beige mice (C57 BL/6 bg/bg) were treated intraperito‐neally with NK cells obtained from MAC‐infected and uninfected C57 black mice. Peritoneal macrophages harvested from beige mice treated with NK cells activated in vitro with IL‐2 killed 24.4 ± 4% of intracellular bacteria by day 4 after infection. Macrophages obtained from animals treated with NK cells harvested from MAC‐infected black mice killed 58.8 ± 7% of intracellular bacteria by 4 days after infection, in contrast with intracellular growth observed in macrophages obtained from untreated animals and from animals treated with Hanks' solution or unactivated NK cells. These crossover studies suggest that NK cells may be important in host defense against MAC.