CD95 signaling is not required for the down regulation of cellular responses to systemic Mycobacterium tuberculosis infection.
There is a tendency among tuberculosis patients to have reduced cellular responses to mycobacterial antigens and this loss has been associated with apoptosis of CD4 T cells. In order to determine the role of CD95 in mediating apoptosis of antigen-specific lymphocytes in tuberculosis, mice with a mutated CD95L molecule were infected systemically with virulent Mycobacterium tuberculosis. Both control and CD95L mutant mice exhibited the expected loss of response to mycobacterial antigens, with the only difference being a slight delay in the loss of the response in the mutant mice. The limited persistence of the response in the mutant mice suggests that, while antigen-specific cellular responses do decline in mice infected with mycobacteria, this decline is not dependent upon CD95L.
Pearl
J E
JE
Mycobacterial Research Laboratories, Department of Microbiology, Colorado State University, Fort Collins, CO 80523, USA.
Orme
I M
IM
Cooper
A M
AM
D000818:Animals; D017209:Apoptosis / Q000502:physiology; D015169:Colony Count, Microbial; D003124:Colorimetry; D015536:Down-Regulation / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay; D053222:Fas Ligand Protein; D005434:Flow Cytometry; D007111:Immunity, Cellular / Q000502:physiology; D008213:Lymphocyte Activation; D008562:Membrane Glycoproteins / Q000235:genetics*; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification; D016176:T-Lymphocyte Subsets / Q000276:immunology*; D014376:Tuberculosis / Q000276:immunology*; D019014:fas Receptor / Q000276:immunology*
D053222:Fas Ligand Protein; C505658:Fasl protein, mouse; D008562:Membrane Glycoproteins; D019014:fas Receptor