Open AccessLysis of human macrophages by cytolytic CD4 + T cells fails to affect survival of intracellular Mycobacterium bovis ‐bacille Calmette‐Guérin (BCG)
Author(s) -
FAZAL N.,
LAMMAS D. A.,
RAHELU M.,
PITHIE A. D.,
GASTON J. S. H.,
KUMARARATNE D. S.
Publication year - 1995
Publication title -
clinical & experimental immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.329
H-Index - 135
eISSN - 1365-2249
pISSN - 0009-9104
DOI - 10.1111/j.1365-2249.1995.tb03476.x
Subject(s) - cytolysis , microbiology and biotechnology , biology , lysis , intracellular parasite , intracellular , mycobacterium bovis , antigen , mycobacterium , bacteria , immunology , macrophage , virology , immune system , in vitro , cytotoxicity , mycobacterium tuberculosis , medicine , tuberculosis , biochemistry , genetics , pathology
SUMMARY Human CD4 + , mycobacteria‐specific, cytolytic T cell clones were used to lyse BCG‐infected macrophages. and the effect on the subsequent growth and viability of the organisms was examined. The survival of released bacteria following cell lysis was assessed by both 3 H‐uridine labelling and colony‐forming unit (CFU) estimation. The results indicate that even when effective antigen‐specific or lectin‐mediated cytolysis of the infected macrophages was achieved, there was no evidence for a direct mycobactericidal effect on the intracellular bacteria. This remained the case even if the period of co‐culture of T cells and macrophages was extended up to 48 h. Pretreatment of the macrophages with interferon‐gamma (IFN‐γ) was not able to act together with T cell‐mediated lysis to produce inhibition of mycobacterial growth.