[Experimental study on the inhibition of fibroblast contraction by alpha smooth muscle actin fusion protein].
OBJECTIVE
To investigate the influence of alpha smooth muscle actin fusion protein (alpha-SMA-FP) on fibroblast contraction, in order to find a new way to control scar contracture.


METHODS
Three dimensional gel culture model of fibroblasts populated collagen lattices (FPCLs) was employed in the study. The fibroblasts were cultured in gel for 5 days. The cells in experimental group were processed by alpha-SMA-FP in dose of 5, 10, 50, 100 and 250 mg/L, respectively. The cells were therefore divided into E(1), E(2), E(3), E(4) and E(5) groups. Blank control was set to be C(1) group, and the cells processed by 250 mg/L of alpha-SMA-FP be C(2) group. The contraction rate was calculated by measuring the diameters of the gel before and after the procession. The change of contraction rate in E5 group was observed after the alpha-SMA-FP being rinsed out. Immunofluorescent staining of alpha-SMA-FP was carried out in fibroblasts.


RESULTS
The contraction rate in C1 and C2 groups showed no difference, being (58.6 +/- 3.1)% and (56.2 +/- 4.9)% respectively, while that in E1 to E5 groups was (45.56 +/- 4.1)%, (42.3 +/- 4.2)%, (41.8 +/- 3.6)%, (37.6 +/- 5.8)% and (26.4 +/- 4.7)%, respectively. However, the contraction rate in E5 was (53.3 +/- 5.6)% after the alpha-SMA-FP had been rinsed out. The difference of the rates among control group and experimental groups, especially in E5 after alpha-SMA-FP being rinsed out, was significant (P < 0.05 or 0.01). alpha-SMA-FP was located on the fibers of the fibroblasts as shown by staining, while the alpha-SMA was not stained. Nevertheless, the staining was obvious in control group.


CONCLUSIONS
alpha-SMA-FP could inhibit the contraction of fibroblasts specifically with dose dependent effect.
Jia
Chi-yu
CY
Centre of Burn and Rehabilitation, Peking Union Medical College Hospital, Beijing 100032, P.R. China.
D000199:Actins / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005347:Fibroblasts / Q000187:drug effects* / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar
D000199:Actins; C498862:Acta2 protein, rat