CD147 Plays Functional Role In The Differentiation Of HEL Cells

The development and maturation of hematopoietic cells are highly dependent on their interactions with stromal cells and extracellular matrix, and adhesion molecules play an important role in these interactions. CD147, also named Matrix metalloproteinase inducer , is considered an adhesion molecul that invovles in many pathological and physiological processes, such as cancer and haematopoiesis. It is expressed in various tissues, including brain, leukocytes, endothelial cells, and most tumor cell lines.Recent studies showed that CD147 was expressed on erythrocyte lineage cells throughout erythroid development, including in mature erythrocytes, Blockade of CD147 on the cell surface by treatment of anti-CD147 monoclonal antibody disrupts the circulation of erythrocytes, leading to their selective trapping in the spleen and consequent de novo erythropoietin-mediated erythropoiesis in the spleen.It's known that the development and maturation of platelet and red blood cells is closely related and they probably had the same progenitor cells. So this interests us to investigate the roles of CD147 in the differentiation and development of megakaryocytic cells.We found that CD147 was expressed on the surface of platelets and the expression was increased when platelets were activated by thrombin, and the expression and activity of MMPs were upregulated too . Then the expression of CD147 and MMPs in the differentiation of a human erythroleukemia (HEL) cell line which underwent megakaryocytic differentiation incubated with TPA, was also investigated. The results showed that the expression level of CD147 and MMP of HEL cell in the absence of TPA was low. TPA incubation of HEL cells resulted the upregulation of CD41, the biomarker of megakaryocytic cells, as well as the CD147. MMP inhibitor abolished the effects of TPA. This indicated that MMPs were involved in the TPA induced differentiation of HEL.In order to investigate the relation between CD147 and MMPs during the differentiation of HEL cells, CD147 gene was transduced into HEL cells by a lentiviral vector, and the CD147 expressing HEL cells were induced by TPA. The morphology of the cell , the expreesion of CD41 as well as the activity of MMP was detected. The results showed that the over-expression of CD147 promoted the differentiation of HEL cells and MMP inhibitor decreased the CD41 expression. This suggested that CD147 played functional role in HEL differentiation and was probably related with its function of induction of MMP activity.