OX40 ligand
OX40L is the ligand for OX40 and is stably expressed on many antigen-presenting cells such as DC2s, macrophages, and activated B lymphocytes.
The OX40 molecule, on the other hand, is present on the surface of activated T lymphocytes, but also on NK cells, NKT cells, and neutrophils. The ligation of OX40-OX40L is a source of survival signal for T cells and enables the development of memory T cells. Signalization through these two molecules also leads to polarization towards Th2 immune response even in the environment with low levels of IL-4 cytokine.
OX40L is also present on the surface of many non-immune cells, for example on the endothelial cells and the smooth muscle cells.
The surface expression of OX40L is induced by many pro-inflammatory mediators, such as TNF-α, e.g. produced by mast cells, IFN-γ and PGE2.
OX40L has also been designated CD252.
Various single-nucleotide polymorphisms of the OX40L gene have been identified. For some of them association with systemic lupus erythematosus has been reported: No association with occurrence of atherosclerosis has been found.
