Abstract: Objective To investigate whether human bone marrow stroma stem cells（hMSCs）differentiate into conjunctival epithelium-like cells. Methods The hMSCs and human conjunctival epithelial cells(hCjEs) were isolaed and cultured. The morphological characteristics of the hMSCs and hCjEs were observed under a phase contrast microscope, and the cells were identified according to their morphology and cell-surface antigen profiles by immunocytochemical analysis. The hMSCs were co-cultured with hCjEs in Trans-well. The differentiated cells were identified according to their morphological characteristics,and the expression of cytokeratin13 (CK13) protein was detected by immunocytochemistry. The abundance of the mRNAs for CK13 in hCjEs，differentiated cells and hMSCs without co-cultured with hCjEs were determined by reverse transcriptasepolymerase chain reaction（RT-PCR）. BR> Results The hMSCs showed spindle-like morphology and the adherent cells showed whirlpool-like shape. The hCjEs were shown in shape of irregular round or polygon, and the adherent cells showed paving stones-like shape. The results of immunocytochemistry showed that there was positive expression of CD44 and CD29 in hMSCs. The hCjEs had positive expression of CK13 After induced by conjunctival epithelium, the shape of differentiated cells became wide and irregularly round accompanied by losing its spindle-shape. The results of immunocytochemistry showed that there was positive expression of CK13 in differentiated cells, and the expression of CK13 mRNA was detected by RT-PCR. No mRNA products were detected in the hMSCs without co-culturing with conjunctival epithelium. Conclusion The hMSCs and hCjEs are successfully cultured and expanded with high purity in vitro. Conjunctival epithe1ium-like cells

Key words: Stem cells, Differentiation, Cell culture, Epithelial cells, Immunohistochemistry