Fig. 5From: In vitro immune responses of porcine alveolar macrophages reflect host immune responses against porcine reproductive and respiratory syndrome virusesSerum cytokine levels in PRRSV-infected pigs. Sera collected from pigs (n = 5) at 0, 3, 7, 14, 21 and 28 dpc were analysed for a IFN-α; b TNF-α; c IL-12; d IL-10; and e IL-4 by ELISA. Each bar represents the average cytokine amount from 5 pigs ± SEM. Bars showing different letters represent values that differ significantly from each other (p < 0.05)Back to article page