Interleukin-6 monoclonal antibody suppressed hypertrophic scar induced by mechanical tension

Abstract

Objective To study the effect of interleukin-6 monoclonal antibody (IL-6 mAb) on rats hyperplastic scar induced by mechanical tension. Methods Fifty male C57/BL6 rats were divided into five groups according to random and equilibrium principles: normal control group, sham positive group, model group, IgG group, IL-6 mAb group. The latter 3 groups of rats were applied mechanical tension to build rats model of hyperplastic scar induced by mechanical tension, tension lasting for 2 weeks before dismantling device, rats in sham positive group were not applied mechanical tension. In the third, fourth and fifth week, rats in the latter 2 groups were injected with IgG and IL-6 mAb through tail intravenous, respectively. However, the ones in the other three groups were injected with the same volume saline instead. All rats were executed after 5 weeks, cut the scar tissue, and detection was made using the morphology, histology, molecular biology method. Results Compared with control group, the IgG had no obvious effect on hyperplasia scar, nevertheless, in IL-6 mAb group, scar area was significantly narrowed, histological tests showed the decrease in the contents of collagen in IL-6 mAb group (all P=0.000). Enzyme linked immunosorbent assay (ELISA) showed that IL-6 mAb reduced the expression of proinflammatory factor (all P=0.000); real-time quantitative PCR (RT-qPCR) and Western blotting indicated that IL-6 mAb could also knock down mRNA and protein expression of type Ⅰ collagen (Col Ⅰ) and Ⅲ collagen (Col Ⅲ) (all P=0.000). Conclusion IL-6 mAb could inhibit rats hyperplastic scar formation induced by mechanical tension, probably through inhibiting the secretion of proinflammatory factor and the synthesis of collagen. Key words: Interleukin-6 monoclonal antibody; Mechanical tension; Hyperplastic scar; Rats’ model