OBJECTIVETo study the effects of recombinant human interleukin-11 (rhIL-11) on the proliferation and apoptosis of rat intestinal epithelial cell line (IEC-6).

METHODSIEC-6 cells were treated with LPS to establish necrotizing enterocolitis (NEC) model in vitro. rhIL-11 (100 ng/mL) was administered following LPS treatment and these cells were used as the IL-11 treatment group. The cells treated with normal saline only served as the control group. MTT assay was used to determine an optimal concentration (5-200 μg/mL) and time (1-24 h). MTT assay was used to measure the proliferation of IEC-6 cells at 3, 6, 9 and 12 hours after rhIL-11 treatment. Flow cytometry was used to evaluate the apoptosis of IEC-6 cells.

RESULTSIEC-6 cells treated with various concentrations of LPS at various time points showed a lower proliferation than the control group (P<0.05). After 9 hours of rhIL-11 treatment, the proliferation activity of IEC-6 cells in the IL-11 treatment group significantly increased compared with the NEC model group without rhIL-11 treatment (P<0.05), reaching to the level of the control group. The total apoptotic and necrotic rate of IEC-6 cells in the IL-11 treatment group decreased significantly compared with the NEC model group without rhIL-11 treatment (P<0.01), but were still higher than the control group (P<0.05).

CONCLUSIONSrhIL-11 can promote proliferation and reduce apoptotic and necrotic rates of IEC-6 cells treated with LPS.