@article {542766,
	title = {ICOS is critical for CD40-mediated antibody class switching.},
	journal = {Nature},
	volume = {409},
	number = {6816},
	year = {2001},
	month = {2001 Jan 4},
	pages = {102-5},
	abstract = {The inducible co-stimulatory molecule (ICOS) is a CD28 homologue implicated in regulating T-cell differentiation. Because co-stimulatory signals are critical for regulating T-cell activation, an understanding of co-stimulatory signals may enable the design of rational therapies for immune-mediated diseases. According to the two-signal model for T-cell activation, T cells require an antigen-specific signal and a second, co-stimulatory, signal for optimal T-cell activation. The co-stimulatory signal promotes T-cell proliferation, lymphokine secretion and effector function. The B7-CD28 pathway provides essential signals for T-cell activation, but does not account for all co-stimulation. We have generated mice lacking ICOS (ICOS-/- ) to determine the essential functions of ICOS. Here we report that ICOS-/- mice exhibit profound deficits in immunoglobulin isotype class switching, accompanied by impaired germinal centre formation. Class switching was restored in ICOS-/- mice by CD40 stimulation, showing that ICOS promotes T-cell/B-cell collaboration through the CD40/CD40L pathway.},
	keywords = {Animals, Antibody Formation, Antigens, CD40, Antigens, Differentiation, T-Lymphocyte, B-Lymphocytes, CD4-Positive T-Lymphocytes, CD40 Ligand, Gene Targeting, Germinal Center, Hemocyanin, Immunoglobulin Class Switching, Immunoglobulin Isotypes, Inducible T-Cell Co-Stimulator Protein, Mice, T-Lymphocytes},
	issn = {0028-0836},
	doi = {10.1038/35051107},
	author = {McAdam, A J and Greenwald, R J and Levin, M A and Chernova, T and Malenkovich, N and Ling, V and Freeman, G. J. and Sharpe, A. H.}
}
