ICOS (Inducible Costimulator) modulates cytokine responses in human tuberculosis.

GUSTAVO J. MARTÍNEZ; VIRGINIA PASQUINELLI; M. FLORENCIA QUIROGA; JAVIER O, JURADO; ROSA M. MUSELLA; LILIANA CASTRO ZORRILLA; MATÍAS BALDINI; EDUARDO ABBATE; VERÓNICA E. GARCÍA.

Cordoba, Argentina.

Congreso; VII Latinamerican Congress of Immunology; 2005

Latin American Association of Immunology (ALAI)

Effective host defense against Mycobacterium tuberculosis (Mtb) requires Th1 cytokine responses. ICOS, a trans-membrane protein expressed on lymphocytes, promotes T cell proliferation and cytokine production. We investigated the role of ICOS in patients with tuberculosis (TB). Peripheral blood mononuclear cells from TB patients were stimulated with Mtb antigen for 5 days and co-stimulation through ICOS was then performed using anti-ICOS agonistic antibody. Two days later, IFN-g production and T-bet and GATA-3 expression were measured by ELISA and Western blot respectively. In High Responder (HR) TB patients (individuals that display significant Mtb-dependent T cell responses), ICOS ligation in Mtb-stimulated T cells significantly up-regulated IFN-g production (p