Serum levels of IL-1β, IL-6, TNF-α, and IL-10 following IP injection of saline, male MSCs, or female MSCs in rats pretreated with saline or LPS. Rats treated with MSCs of either sex had significantly decreased expression of IL-1β (A), TNF-α (B), and IL-6 (C) and significantly increased expression of IL-10 (D) compared with vehicle. *P < 0.05 vs. control; #P < 0.05 vs. vehicle; &P < 0.05 vs. vehicle.