Lethal pulmonary infection with Francisella novicida causes depletion of alphabeta T cells from lungs.
Respiratory Francisella infections induce a delayed innate immune response followed by a severe sepsis like condition. In this study, mice infected intranasally with Francisella novicida showed a depletion of alphabeta T cells in lungs while exhibiting large accumulations of other leukocytes correlating with disease severity. The depleted T cells were predominantly CD4(+). The alphabeta T cells in infected mice showed significantly higher levels of Annexin V binding than those in mock control mice suggesting increased apoptosis of T cells. These results suggest that lack of transition from an innate to adaptive host response is associated with lethality of respiratory tularemia.
Department of Biology, South Texas Center for Emerging Diseases, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX 78249-1644, USA.
Jyotika
J
Sharma
Qun
Q
Li
Bibhuti B
BB
Mishra
Judy M
JM
Teale
D000818:Animals; D017304:Annexin A5 / Q000276:immunology / Q000378:metabolism; D017209:Apoptosis / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000382:microbiology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000382:microbiology; D005260:Female; D005603:Francisella / Q000276:immunology*; D008168:Lung / Q000276:immunology / Q000382:microbiology; D008171:Lung Diseases / Q000276:immunology* / Q000382:microbiology; D008212:Lymphocyte Depletion; D051379:Mice; D008810:Mice, Inbred C57BL; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000276:immunology* / Q000378:metabolism; D014406:Tularemia / Q000276:immunology* / Q000382:microbiology
D017304:Annexin A5; D016693:Receptors, Antigen, T-Cell, alpha-beta