Screening of the optimal CpG-oligodeoxynucleotide for anti-inflammatory responses in avian macrophage cell line HD11
CpG-oligodeoxynucleotides (CpG-ODN) has been shown to possess immunostimulatory features in both mammals and birds. However, compared to its pro-inflammatory effects, little is known about the anti-inflammatory responses triggered by CpG-ODN in avian cells. Hence, in this study, we aimed to characterize the anti-inflammatory response in the chick macrophage cell line HD11 under the stimulation of five kinds of CpG-ODN: CpG-A1585, CpG-AD35, CpG-B1555, CpG-BK3, and CpG-C2395. Single-stimulus CpG-B1555, CpG-BK3, and CpG-C2395 induced the interleukin (IL)-10 expression without causing cellular injury. The effects of pretreatment with each CpG-ODN before subsequent lipopolysaccharide stimulation were also evaluated. Interestingly, only CpG-C2395 maintained a high expression level in this situation. Finally, expression analysis of inflammation-related genes, such as the tumor necrosis factor-, IL-1{beta}, IL-6, and Toll-like receptor 4, was conducted, and pretreatment with CpG-C2395 significantly reduced their expression. Overall, our results shed light on the anti-inflammatory responses triggered by CpG-C2395 stimulation using a comparative analysis of three major classes of CpG-ODN in chick macrophages.