Cloning Of Differentially-expressed Genes In Human Dental Pulp Cells And Sequence Analysis Of DPDP-2 And DPDP-3

With dental pulp tissue injured, infected by external factors, human dental pulp cells can proliferate, differentiate into odontoblast-like cells and secrete reparative dentin. This is biologically fundamental for the self-reparative potential of dental pulp tissue. Nowadays, the molecular mechanism of proliferation and differentiaton of dental pulp cells has been one of the focuses in the field of dental pulp biology.In the past several years, owing to the further development of modern cellular biology and molecular biology, there has been a great amount of research on molecular mechanism of dental pulp cellular differentiation. Subtractive hybridization is a technique used to clone differentially-expressed genes in cells. According to the principle of this technique, cDNA from different cells are hybridized to isolate unhybridized fragments, and the unhybridized fragments are cloned and analyzed. It has been established that human dental pulp cells are different from other fibroblasts, i.e. the former can differentiate into odontoblast-like cells, whereas human gingival fibroblasts (HGF) can't. In the present study, based on this principle, differentially-expressed genes were cloned from human dental pulp cells by using improved subtractive hybridization based on PCR (LPS). The objective of the study was to work out the molecular mechanism of the proliferation and differentiation of human dental pulp cells and to provide some data for further experiments and research.The study consists of 3 parts described as below.1. Primary culture of human dental pulp cells and human gingival fibroblastsHuman dental pulp cells and HGF were cultured by tissue explant culture technique. The success rates of the primarily-cultured cells were 16.7% and 40% respectively. The population doubling times of the cultured cells were 52.9h and 47.6h respectively. The cultured cells were shuttle-shaped, plump in form, homogenous in cytoplasma and their nuclei looked clear and round. There was no significant difference between the shapes of...