[Study of the effects of integrin-linked kinase on proliferation and differentiation of fibroblast in hypertrophic scar].

Objective: To study the role of integrin-linked kinase (ILK) on the proliferation and differentiation of human fibroblast in hypertrophic scar and its effect on the scar formation.
Methods: The human scar fibroblasts were isolated and cultured in vitro. The cells were divided into 4 groups. (1) control group: only contains DMEM; (2) jetPRIME group: DMEM with 200 microl jetPRIME buffer and 4 microl jetPRIME; (3) ILK siRNA group: DMEM and ILK siRNA; (4) ILK cDNA group: DMEM and ILK cDNA. The cell proliferation was detected by XTT assay and the mRNA and protein expressions of ILK and alpha-SMA were detected by Real-time qPCR and Western blot.
Results: (1) XTT results showed that the cellular proliferation level after 48 h in four groups were 0.820 +/- 0.065, 0.873 +/- 0.041, 0.554 +/- 0.013 and 1.296 +/- 0.094, respectively. The cellular proliferation curve showed that the cellular proliferation level was very flat in ILK siRNA group while the cellular proliferation level gradually increased from 12 h. 48 h after transfection, the cellular proliferation level in ILK siRNA group was significant lower than those in other groups (P value were 0.021, 0.034, 0), while the cellular proliferation level in ILK cDNA group was the highest among all 4 groups (P value were 0.017, 0.009, 0). (2) The Real-time qPCR showed that the expressions of ILK mRNA and alpha-SMA mRNA were 0.693 +/- 0.412 and 0.422 +/- 0.037 in control group, were 0.621 +/- 0.183 and 0.388 +/- 0.005 in jetPRIME group, were 0.052 +/- 0.019 and 0.073 +/- 0.023 in ILK siRNA group, were 240.193 +/- 35.170 and 138.056 +/- 24.060 in ILK cDNA group. The expressions of ILK mRNA and alpha-SMA mRNA in ILK siRNA group were significantly lower than those in other three groups (P < 0.05). And the expressions of ILK mRNA and alpha-SMA mRNA in ILK cDNA group were significantly higher than those in other three groups (P < 0.05). (3) The Western blot also showed that the expression of ILK and alpha-SMA proteins were decreased in ILK siRNA group and increased in ILK cDNA group.
Conclusion: ILK may promote the proliferation and differentiation of human scar fibroblast. It may play an important role in scar formation and contracture.