OBJECTIVETo investigate the influence of epidermis from different sources on the proliferation and metabolism of fibroblasts (Fb), and to explore its cause.

METHODSIn a co-culture system, normal Fb (A group) and cicatricial Fb(B group) from 10 patients with scar during proliferative stage were co-cultivated with own normal skin epidermis (NSE), respectively, without direct contact. In control groups (C group), cicatricial Fb was cultured alone. Normal Fb and cicatricial Fb from 10 patients with scar during maturation period were co-cultured with own normal skin epidermis as mentioned above, and divided into D, E and F groups. The cell number of FB, the amount of type I and III procollagen (PC I, PC III) in the supernatants and the PC I to PC III ratio were determined.

RESULTSTo compare the C with A group and the F with D group, Fb in C and F groups exhibited increased cell number and PC I , PC III amounts (P < 0.05), and decreased ratio of PC I to PC III (P < 0.05). To compare the B with C group, PC III contents in the cell supernatant was increased (P < 0.05), and the ratio of PCI to PC III decreased in B group (P < 0.05), there were no obvious difference in Fb cell number and the amount of PC I contents between B and C group. To compare the E with F group, the cell number of Fb, as well as PC I and PC III contents in cell supernatant were obviously decreased in E group (P < 0.05), but no obvious decrease was observed in the ratio of PC I and PC III. To compare the B with A group and the E with D group, the cell number and the PC I and PC III contents in B and E groups were evidently increased, while the ratio of PC I to PC III decreased markedly (2.20 +/- 0.27 vs 1.16 +/- 0.21 in A, B group, P < 0.05; 2.18 +/- 0.14 vs 1.93 +/- 0.26 in D, E group, P < 0.05).

CONCLUSIONNormal epidermis may play an important role in preventing hypertrophic scar by producing some bioactive substances.