2007 Volume 30 Issue 8 Pages 1384-1389
Schizophyllan (SPG) is used to treat cervical cancer in combination with irradiation to enhance the immunological surveillance system. Dectin-1 is a cell surface receptor for 1,3-β-glucan. In this study, we prepared two anti-Dectin-1 monoclonal antibodies, 4B2 and SC30 having a KD of 7.04×10−8 M and 1.55×10−7 M, respectively, and evaluated the role of Dectin-1 in SPG-induced anti-tumor activity in mice. Expression of Dectin-1 on peritoneal macrophages and binding of SPG to the cells were decreased by administration of 4B2 and SC30. SPG-mediated anti-tumor activity was inhibited by 4B2 and SC30. 4B2 and SC30 inhibited the binding of SPG to splenocytes from mice. The binding of SPG-biotin to Dectin-1-transfected HEK293 cells was inhibited by 4B2, but not SC30. 4B2 and SC30 differ in their influence on Dectin-1 between primary cells and transduced cells, and Dectin-1 effects 1,3-β-glucan-mediated anti-tumor activity in mice by binding to SPG.