CD80 and cancer: More specifically, increases in DC and macrophage levels were observed and may correspond to the presence of high GmCSF expression after pEEVGmCSF-b7.1 transfection, as previous studies have shown that GmCSF−/− mice have reduced DC and macrophage recruitment and survival.31, 32 Several studies have also indicated that B cells can respond to GmCSF. 33 Within cancer immunology, B cells are currently underinvestigated, but appear to have a complex role.