OBJECTIVETo research the effects of recombinant human beta-defensin-3 (hBD-3) on expression of interleukin-17A (IL-17A) and interleukin-22 (IL-22) in BEAS-2B cell.

METHODSThe BEAS-2B cells were stimulated with different concentrations of hBD-3 for 6 hours and 24 hours, respectively. Toll-like receptor 2 (TLR2), IL-17A and IL-22 mRNA expression levels were determined by real-time PCR, and the expression levels of IL-17A and IL-22 protein were examined by enzyme linked immune-sorbent assay.

RESULTSTLR2 mRNA in BEAS-2B cells were significantly increased in a concentration-and time-dependent manner after stimulating by hBD-3 for 24 hours compared to 6 hours. The IL-17A has significantly increased in mRNA and protein levels stimulated 24 hours in a concentration of 100 ng/ml, however, IL-17A mRNA expression has increased while protein didn't change stimulated 6 hours in a concentration of 50 ng/ml. The IL-22 mRNA and protein expression reached peak levels after stimulating in a concentration of 50 ng/ml of hBD-3 while IL-22 expression declined in mRNA and protein levels as the concentration of hBD-3 increased.

CONCLUSIONSRecombinant hBD-3 can up-regulated the expression of TLR2, IL-17A and IL-22, lower concentration of hBD-3 mainly increased the expression of IL-22 while higher concentration of hBD-3 mainly increased the expression of IL-17A. These results show that different concentrations of hBD-3 maybe activate different transcription factors which was mediated by TLR2, initiating host immune response.