Papers by Author: Guang Dong Zhou

Abstract: Organ engineering remains a challenge to researchers. We tried to reconstruct kidney-like tissue using tissue engineering technique. Kidney fragments were isolated from rat E16 embryonic kidneys and seeded on either ECM gel or on polyglycolic acid (PGA) fibers, then implanted in vivo into the subcutaneous tissue of nude mice for 2 and 3 weeks, respectively. As a negative control, ECM alone was implanted. Results showed that kidney like tissue could be formed in ECMfragment constructs after 2 or 3 weeks of implantation, including the formation of glomeruli, tubules and collecting ducts. In addition, these structures seemed more mature in 3 weeks specimens than that of 2 weeks. Further development of this model may lay a solid foundation for kidney tissue engineering.

Abstract: Bone Marrow Stromal Cells (BMSCs) have chondrogenesis potential if chondrogenic environments or factors are provided. This study tests the hypothesis that chondrocytes can promote BMSC chondrogenesis at non-chondrogensis site. Porcine BMSCs and auricular chondrocytes were mixed at different ratios and 2.5×107 mixed cells were resuspended in 0.5 ml 30％ Pluronic, and then the mixture was injected into nude mice subcutaneously as experimental groups. Chondrocytes or BMSCs at the same cell number were mixed with 0.5 ml Pluronic and injected respectively as controls. 2.5×107 chondrocytes were mixed and injected as low concentration chondrocyte control. 8 weeks later, all specimens in experimental groups and chondrocyte group formed mature cartilage with abundant collagen II expression. Mature lacuna structures and metachromatic matrices were also observed in these specimens with the same level of GAG contents. Average wet weight of specimens in experimental groups was over 70% of that in chondrocyte group. In contrast, specimens in BMSC group showed mainly fibrous tissue. Only a small amount of cartilage was formed in specimens of low concentration chondrocyte group and the average wet weight was below 30% of that in chondrocyte group. These results demonstrate that chondrocytes can provide chondrogenic microenvironment and thus promote in vivo chondrogenesis of BMSCs at non-chondrogenesis sites. It also indicates that Pluronic is an ideal injectable biomaterial for cartilage tissue engineering.