Histocompatibility of poly(lactic-co-glycolic acid)/RNA Ⅲ inhibiting peptide sustained release microspheres / 中国组织工程研究

ABSTRACT

OBJECTIVE:To evaluate the histocompatibility of poly(lactic-co-glycolic acid)/RNA Ⅲ inhibiting peptide(PLGA/RIP)sustained release microspheres.METHODS:The crude peptide comprising N to C-terminals was synthesized using Fmoc method.The crude synthetic RNAIII peptide was purified by reverse phase high performance liquid chromatography,followed by component harvesting according to ultraviolet absorption peak,and freeze-drying.PLGA/RIP sustained release microspheres with a diameter of 50-70?m were prepared using liquid-phase multiple emulsion method.The histocompatibility of PLGA/RIP sustained release microscopes were preliminarily evaluated through the use of acute general toxicity test,MTT cytotoxicity test,intramuscular implantation test,sensitivity test,and pyrogen test.RESULTS:Acute general toxicity test results showed that all included animals survived and presented with no toxicosis reaction and obviously changed body mass.MTT cytotoxicity test results revealed that the average relative growth rate of cells from two eluents was over 85%,with cytotoxicity grade 1,which indicates no cytotoxicity.Intramuscular implantation tests showed that at 4 weeks after implantation of RIP powder or PLGA/RIP microscopes,no obviously congested,degenerated,or necrotic tissue was observed.All RIP powder and a part PLGA/RIP microscopes were degraded.Fibroblasts accounted for a large proportion in all cells.No inflammatory cell infiltration,involving neutrophils and multinucleated giant cells,was observed.Sensitivity test results displayed that the average primary irritation index was 0.38,0.33,and 0.31 in the eluent stock solution,2% dinitoflruorobenzene,and physiological saline-administerd groups,respectively.Pyrogen test results showed that fervescence of each rabbit in the experiment was under 0.5℃ and the sum of fervescence was under 1.3℃.This is in coincidence with evaluation criteria of pyrogen test.CONCLUSION:PLGA/RIP sustained release microspheres exhibit good histocompatibility.