Experimental study on the compound culture of small intestinal submucosa with synovial mesenchymal stem cells

Abstract

Objective To investigate the biosecurity and biocompatibility of small intestinal submucosa （SIS） as scaffold for tissue engineering and to explore the possibility to induce synovial mesenchymal stem cells （SMSCs） differentiate into cartilage with SIS as the scaffold and SMSCs as the seed cells. Methods The SMSCs were isolated and cultured from the synovial mem-brane of knee joints of rabbits by a conventional method. The SIS was harvested from pigs according to the physical method and Abraham＇s method. 4 rabbits are divided into the experimental group and control group. The biosecurity of SIS as scaf-folds were investigated in pyrogen test, skin sensitization test and systemic toxicity test. The SMSCs and SIS were co-cultured in vitro and induced to differentiate into cartilage to explore the biocompatibility of SMSCs and SIS, the proliferation and differ-entiation ability of SMSCs on the scaffold of SIS. The varietyies were identified by the microscope. Results The SIS isolated with the physical method and Abraham＇s method is a milky and translucent membrane with a smooth surface. Under the electron microscope, SIS presented a porous Stereoscopic three-dimensional network structure, which is formed by fibrous tissues＇ intertex-ture. Its＇ porosity was about 80%and its aperture was 100-200μm. Meanwhile, the biosecurity and biocompatibility of SIS were also fine. In the trial that the SMSCs and SIS were co-cultured in vitro, the SMSCs can grow, adhere to and differentiate on the sur-face of SIS and into the hollows very well. It can also secrete extracellular matrix. Through scanning microscope observation, cells contact with each other by their neuritis, or adhered to the wall of hole by cellular protrution. On the surface of SIS, the SMSCs maintain the property that it can easily differentiate into the chondrogenic lineage in the chondrogenic medium. Immunochemistry staining showed positive expression of type II collagen post 21 days of co-cultrue. Conclusion SIS can be used as the scaffold to construct tissue engineering meniscus as it has good biosecurity and biocompatibility with SMSCs without disturbing the cell form or inhibiting the growth and function of SMSCs. Key words: Mesenchymal stem cells Intestine; small Intestinal mucosa Materials testing