In the HLN, the absence of differential IL-10 expression among the UC group and the three infected groups agreed with the results of a previous study in sheep primoinfected with F. hepatica but contrasted with the increased IL-10 expression in reinfected sheep [22], and also contrasted with the higher expression of this cytokine in the HLN of buffaloes infected with F. gigantica during both acute and chronic states of infection [36]. Here, IL10 is linked to infection.