Fig. 4
Indirect stimulation of canine ASCs and PMSCs in leukocyte suppression assay (LSAs) leads to production of IDO and PGE2. Canine adipose-derived MSCs (ASCs) and placenta-derived MSCs (PMSCs) produce similar secretory mediators when co-cultured in contact with activated peripheral blood mononuclear cells (PBMCs). a ASCs and PMSCs increase indoleamine 2,3 dioxygenase (IDO) activity in the presence of mitogen (ConA) activated PBMCs. Removal of direct cellular contact did not alter IDO activity by either ASCs or PMSCs. b Production of prostaglandin E2 (PGE2) occurred in both standard and transwell conditions. Canine PMSCs secrete significantly greater levels of PGE2; however, when direct contact was removed using transwells, only canine PMSCs drastically reduced PGE2 production. No observable changes occur when contact was removed in ASC co-cultures. Data presented as mean and standard error. *p < 0.05, **p < 0.01, ***p < 0.001. ConA, concanavalin A; IDO, indoleamine 2,3 dioxygenase; MSC, mesenchymal stem cell; PBMCs, peripheral blood mononuclear cells; PGE2, prostaglandin E2