T cell expansion is regulated by activated Gr-1+ splenocytes.
CD4+ T cell proliferation depends on the balance between NO and extra-cellular superoxide (O2-). By reducing NO bio-availability, O2- promotes splenic T cell proliferation and immune response intensity. Here, we show that spleen cells from naïve mice produced neither NO nor O2- during T cell activation, but Gr-1+ splenocytes from primed mice regulated Ag-specific T cell expansion via production of both molecules. Purified splenic Gr-1+ cells included mostly granulocytes at various stages of maturation, as well as monocytes. Activation or recruitment of regulatory Gr-1+ cells was dependent on immunization with CFA. Importantly, these regulatory cells were not detected in draining lymph nodes. These data suggest that innate Gr-1+ splenic cells regulate adaptive immunity.
Dietlin
T A
TA
Department of Neurology, University of Southern California Keck School of Medicine, Los Angeles, CA, USA.
Hofman
F M
FM
Gilmore
W
W
Stohlman
S A
SA
van der Veen
R C
RC
D000818:Animals; D049109:Cell Proliferation; D005620:Freund's Adjuvant; D007155:Immunologic Factors / Q000096:biosynthesis / Q000502:physiology; D008055:Lipids; D008213:Lymphocyte Activation / Q000276:immunology; D008285:Major Histocompatibility Complex / Q000502:physiology; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009169:Mycobacterium tuberculosis / Q000276:immunology; D009569:Nitric Oxide / Q000096:biosynthesis / Q000502:physiology; D019707:Receptors, Chemokine / Q000096:biosynthesis*; D016192:Resting Phase, Cell Cycle / Q000276:immunology; D013154:Spleen / Q000166:cytology* / Q000276:immunology / Q000378:metabolism; D013481:Superoxides / Q000378:metabolism / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology* / Q000276:immunology* / Q000378:metabolism
C503133:Gr-1 protein, mouse; D007155:Immunologic Factors; D008055:Lipids; D019707:Receptors, Chemokine; C114843:incomplete Freund's adjuvant; D013481:Superoxides; D009569:Nitric Oxide; D005620:Freund's Adjuvant