TY - JOUR
T1 - Fcγ receptors regulate immune activation and susceptibility during Mycobacterium tuberculosis infection
AU - Maglione, Paul J.
AU - Xu, Jiayong
AU - Casadevall, Arturo
AU - Chan, John
PY - 2008/3/1
Y1 - 2008/3/1
N2 - The critical role of cellular immunity during tuberculosis (TB) has been extensively studied, but the impact of Abs upon this infection remains poorly defined. Previously, we demonstrated that B cells are required for optimal protection in Mycobacterium tuberculosis-infected mice. FcγR modulate immunity by engaging Igs produced by B cells. We report that C57BL/6 mice deficient in inhibitory FcγRIIB (RIIB-/-) manifested enhanced mycobacterial containment and diminished immunopathology compared with wild-type controls. These findings corresponded with enhanced pulmonary Th1 responses, evidenced by increased IFN-γ-producing CD4+ T cells, and elevated expression of MHC class II and costimulatory molecules B7-1 and B7-2 in the lungs. Upon M. tuberculosis infection and immune complex engagement, RIIB-/- macrophages produced more of the p40 component of the Th1-promoting cytokine IL-12. These data strongly suggest that FcγRIIB engagement can dampen the TB Th1 response by attenuating IL-12p40 production or activation of APCs. Conversely, C57BL/6 mice lacking the γ-chain shared by activating FcγR had enhanced susceptibility and exacerbated immunopathology upon M. tuberculosis challenge, associated with increased production of the immunosuppressive cytokine IL-10. Thus, engagement of distinct FcγR can divergently affect cytokine production and susceptibility during M. tuberculosis infection.
AB - The critical role of cellular immunity during tuberculosis (TB) has been extensively studied, but the impact of Abs upon this infection remains poorly defined. Previously, we demonstrated that B cells are required for optimal protection in Mycobacterium tuberculosis-infected mice. FcγR modulate immunity by engaging Igs produced by B cells. We report that C57BL/6 mice deficient in inhibitory FcγRIIB (RIIB-/-) manifested enhanced mycobacterial containment and diminished immunopathology compared with wild-type controls. These findings corresponded with enhanced pulmonary Th1 responses, evidenced by increased IFN-γ-producing CD4+ T cells, and elevated expression of MHC class II and costimulatory molecules B7-1 and B7-2 in the lungs. Upon M. tuberculosis infection and immune complex engagement, RIIB-/- macrophages produced more of the p40 component of the Th1-promoting cytokine IL-12. These data strongly suggest that FcγRIIB engagement can dampen the TB Th1 response by attenuating IL-12p40 production or activation of APCs. Conversely, C57BL/6 mice lacking the γ-chain shared by activating FcγR had enhanced susceptibility and exacerbated immunopathology upon M. tuberculosis challenge, associated with increased production of the immunosuppressive cytokine IL-10. Thus, engagement of distinct FcγR can divergently affect cytokine production and susceptibility during M. tuberculosis infection.
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U2 - 10.4049/jimmunol.180.5.3329
DO - 10.4049/jimmunol.180.5.3329
M3 - Article
C2 - 18292558
AN - SCOPUS:49149094065
SN - 0022-1767
VL - 180
SP - 3329
EP - 3338
JO - Journal of Immunology
JF - Journal of Immunology
IS - 5
ER -