Monoclonal antibody to mouse OX40 (CD134) (Clone: OX-86)

The OX-86 monoclonal antibody reacts with mouse OX-40 also known as CD134. OX-40 is a 50 kDa type I membrane glycoprotein and a member of the TNF receptor superfamily. OX-40 is expressed on activated CD4 and CD8 T cells, but is not found on resting naive T cells or most resting memory T cells. Although it was originally thought that OX-40 expression was restricted to activated conventional T cells, it has now been visualized on activated regulatory T cells, NKT cells, NK cells, and neutrophils. OX-40 plays a major role in regulating both CD4 and CD8 T cell clonal expansion. It provides a costimulatory signal to an antigen-reacting naive T cells to prolong proliferation, as well as augment the production of several cytokines. This is demonstrated by OX-40 knockout mice which generate fewer primary effector CD4 T cells after immunization. Furthermore, in vivo treatment with an agonist antibody to OX-40 has been shown to strongly enhance the generation of antigen-specific effector T cells and prevent the induction of T cell tolerance. The OX-86 antibody is an agonistic antibody that has been shown to delay tumor growth in vivo.