Could OX40 agonist antibody promote activation of the anti‐tumor immune response in gastric cancer?

Background and Objectives OX40, a membrane‐bound molecule of the tumor‐necrosis‐factor‐receptor superfamily, is a critical costimulatory receptor during the immune response, especially to T cells, but studies described their presence of OX‐40 on neutrophils and monocytes, suggesting a potential role in the activation of immune response. Our aim was to characterize costimulatory receptors OX40 expression on circulating leukocytes in gastric cancer to identify novel targets for immunotherapy. Methods Peripheral blood mononuclear cells were isolated from 24 gastric cancer patients and 34 healthy controls and the expression of costimulatory (OX40) receptors were analyzed on T cells, neutrophil and monocyte using monoclonal antibodies by flow cytometry. Results We found that the higher levels of OX40 + T cells, monocytes/OX40+ and neutrophils/OX40+ from gastric cancer patients when compared to controls (P