OBJECTIVETo observe the effect of intestinal trefoil factor (ITF) combined with mucin on the ability of proliferation and migration of intestinal epithelial cells (IEC) after being treated by burn rat serum.

METHODSThe rat IEC-6 cell lines were subcultured and divided into control group (C, cultured with DMEM medium containing 10% calf serum), burn serum group (BS, cultured with DMEM medium containing 10% burn rat serum), burn serum + ITF group (B + I, cultured with DMEM medium containing 10% burn rat serum and 25 microg/mL ITF), burn serum + mucin group (B + M, cultured with DMEM medium containing 10% burn rat serum and 250 microg/mL mucin), and burn serum + ITF + mucin group (B + I + M, cultured with DMEM medium containing 10% burn rat serum, 25 microg/mL ITF, and 250 microg/mL mucin) according to the random number table. Cells were counted on post culture day (PCD) 0, 1, 2, 3, 4, reflecting cell proliferation ability. Cell migration distance was measured at post scratch hour (PSH) 12, 24, 36, 48, 72. Then, cells of each group were placed in upper compartment of Transwell chamber while the corresponding medium was respectively added into lower compartment of Transwell chamber. Cells in lower compartment of Transwell chamber were counted at post culture hour (PCH) 4, 6, 8, 10, 12, reflecting cytomorphosis ability. Data were processed with t test.

RESULTS(1) Cell proliferation ability. The cell numbers in BS group on PCD 0, 1, 2, 3, 4 were significantly less than those in C group (with t values from -16.569 to -2.613, P < 0.05 or P < 0.01). The cell number showed no statistical difference between B + I and BS groups, and between B + M and BS groups at each time point (with t values respectively from 0.037 to 0.740 and 0.116 to 0.429, P values all above 0.05). The cell number in B + I + M group on PCD 2 was respectively larger than that in BS group (t = 6.484, P < 0.01) and B + I group ( t = 3.838, P < 0.01). (2) Cell migration distance in BS group at PSH 12, 24, 36, 48, 72 was significantly shorter than that in C group (with t values from -37.594 to -6.727, P values all below 0.01). There was no obvious difference in cell migration distance between BS and B + M groups at each time point (with t values from 0.055 to 0.589, P values all above 0.05). Cell migration distance in B + I group at PSH 12, 24, 36 was respectively (47 +/- 6), (126 +/- 13), (170 +/- 11) microm, all longer than those in BS group [(42 +/- 7), (98 +/- 14), (154 +/- 22) microm, with t values from 2.230 to 4.817, P < 0.05 or P < 0.01]. Cell migration distance in BS group at PSH 12, 24, 36, 48, 72 and B + I group at PSH 12, 24, 36, 48 was respectively shorter than that in B + I + M group (with t values respectively from 2.982 to 7.390 and 2.707 to 2.918, P < 0.05 or P < 0.01). (3) Cytomorphosis ability. Compared with those of C group, cell counts in lower compartment of BS group at PCH 4, 6, 8, 10, 12 were significantly decreased (with t values from -23.965 to -6.436, P values all below 0.01). Cell count in lower compartment of BS group at PCH 4, 6, 8, 10, 12 was respectively less than that of B + I group (with t values from 3.650 to 10.028, P values all below 0.01) and similar to that of B + M group (with t values from 0.199 to 0.797, P values all above 0.05). Cell counts in lower compartment of B + I + M group at PCH 4, 6, 8, 10, 12 were significantly larger than those of BS group (with t values from 4.313 to 15.100, P values all below 0.01). Cell count in lower compartment of B + I + M group at PCH 10 (328 +/- 47) and PCH 12 (465 +/- 37) was respectively larger than that in B + I group (277 +/- 25, 353 +/- 34, with t value respectively 3.051, 6.945, P values all below 0.01).

CONCLUSIONSITF can improve cytomorphosis ability for promoting cell migration with limited effect on cell proliferation, which can be enhanced with addition of mucin. The main mechanism of ITF in maintaining intestinal mucosal barrier may be attributed to acceleration of cell migration.