ICOS-deficient and ICOS YF mutant mice fail to control Toxoplasma gondii infection of the brain

Th1 cytokine responses fail to effectively control Chlamydia lung infection in ICOS ligand knockout mice.

ICOS ligand (ICOSL) plays an important role in controlling specific aspects of T cell activation, differentiation, and function. Th1-type immune responses have been shown to be critical in host defense against chlamydial infections. To assess the role of ICOSL-ICOS interaction in host defense against chlamydial infection, we compared the immune responses and pathological reactions in ICOSL gene...

Ligand Knockout Mice Lung Infection in ICOS Chlamydia Control Th1 Cytokine Responses Fail to Effectively

Cooperation between 4-1BB and ICOS in the immune response to influenza virus revealed by studies of CD28/ICOS-deficient mice.

CD28, ICOS, and 4-1BB each play distinct roles in the CD8 T cell response to influenza virus. CD28-/- mice are severely impaired in primary CD8 T cell expansion and fail to mount a secondary response to influenza. Influenza-specific CD8 T cells expand normally in ICOS-/- mice, with only a small and transient defect late in the primary response and an unimpaired secondary response. Conversely, 4...

ICOS contributes to T cell expansion in CTLA-4 deficient mice.

Both CD28 and ICOS are important costimulatory molecules that promote Ag-specific cellular and humoral immune reactions. Whereas CD28 is generally thought to be the most important molecule in the initiation of a T cell response, ICOS is considered to act during the effector phase. We have investigated the contribution of ICOS to T cell responses in the absence of CTLA-4-mediated inhibition. Mic...

Abrogation of ICOS/ICOS ligand costimulation in NOD mice results in autoimmune deviation toward the neuromuscular system.

NOD mice spontaneously develop insulin-dependent diabetes around 10-40 wk of age. Numerous immune gene variants contribute to the autoimmune process. However, genes that direct the autoimmune response toward β cells remain ill defined. In this study, we provide evidence that the Icos and Icosl genes contribute to the diabetes process. Protection from diabetes in ICOS(-/-) and ICOSL(-/-) NOD mic...