ABSTRACT
The current problems with corneal transplant,including shortage of donors and immune rejection,could be effectively solved by constructing cornea in vitro with tissue engineering techniques,in which the selection of suitable scaffold materials is especially critical.Chitosan and its derivatives are natural biomaterials with excellent biocompatibility,biodegradability,mechanical property and plasticity,indicating wide application prospects in corneal tissue engineering.This article systematically reviews the research advances in chitosan and its derivatives in corneal tissue engineering,and the existing problems are also highlighted in order to provide theoretical basis for further clinical research.
ABSTRACT
To construct the recombinant vector Pact-EGFP, the Act-1 core promoter region was amplified from the pUCm-T/Act-1 and subcloned into pEGFP-4.1 vector (derived from pEGFP-N1 with the removal of human cytomegalovirus immediate early promoter), by restriction enzymes Bgl II and Hind III. Transfection of Pact-EGFP vector into Vero cell by liposome indicated that Act-1 core promoter regulated the expression of EGFP gene in lower level in Vero cells. After Pact-EGFP microinjection into the gonad of Caenorhabditis elegans with pRF4 as a gene marker, green fluorescence was detected in the cortex, vice cortex and the pharyngeal of C. elegans. According to the locations, two different transgene lines were separated. The expression level of EGFP expressed in C. elegans was more than that in Vero cell. Some unique motifs might exist in Act-1 core promoter region of C. elegans, which was closely related to the expression level of EGFP. These results lay the foundation for the further research on gene function of parasitic nematodes using C. elegans.