Bone marrow-derived mesencbymal progenitor cells are capable of chondrogenesis, making them a possible source of cells for carrtilano tisssee engineering. Because of this, we studied the effect of human transforming growth factor β2 (TGF-β2) on mesenehymal progenitor cell chondrogenesis in monolayer culture using gene transfecion technology. A recombinant pcDNA3.1 (+)/TGF-β2 construct containing a full-length TGF-β2 from a human placental cDNA library was created through gone cloning and DNA recombination. The construct was then lipofected into mesenchymal progenitor cells isolated from human bone marrow. RT-PCR, Western bthrtth, and immunohistochemistry analyses were performed to idemify the expression of TGF-β2 and earilage-associated genes and proteins. The results showed that TGF-β2 was expressed throughout the culture period. The transfected progenitor cells expressed and produced collagen type Ⅱ and aggrecan 48h after transfection, and the expression and synthesis were upregulated after 4 weeks. In contrast, the tested genes and proteins were not detected in non-transfected cells, This shows that transfection of pcDNA3.1(+)/TGF.β2 into mesenchymal progenitor cells is able to provide transient and peristent expression of cartilage-specific genes and proteins, and suggests that the differentiation of human marrow-derived mesenchymal progenitor cell into chondrocytes in monolayer culture is feasible and mky be induced by TGF-β2.