Study Repressing Of Cyclophosphamide On Mice Thymocytes Immunity With Green-fluorescent Protein

Green fluorescent protein (GFP), with excellent natural characteristic, has been used inmany researches as bio-marker, and brings us lots of productions. The objective of thisdissertation was a new application about GFP. We built model about mice thymocytesimmunity by Cyclophosphamide (CY) with bio-marker, studied the effect of bio-marker in thismodel, and the application of the model.Firstly, to screen out the cell in which GFP had high expression rate, cDNA with GFPgene was transported into thymocyte, liver cells and spleen cells in vitro by positive ionpolymer. After 36 hours of transportation, the expression rate of GFP in thymocytes reachedmore than 90%, while in liver cells and spleen cells the rate was less than 10%. And then, in thesame experiment of transporting cDNA into thymocytes, different form of zinc and differentdose was added, but there were no obvious different from the sample without zinc. Then, CYwas chose to make model when transporting in vivo, and mice immunity was study byexpression of GFP. Immunity inhibition of CY has dosage effect, 100mg per kg dose of CYresulting in thymus atrophy obviously, and the same effect of expression rate of GFP.Immunity inhibition of CY also has time effect, expression and the quantity of GFP incells has the same characteristic. When CY being injected into abdominal cavity of mice 18hours, immunity inhibition of CY reached the maximum point. In mice thymus without CYtreating, expression rate of GFP in thymocytes had the peak value after 72~80 hours oftransportation, more than 90%. But treating with CY after 24 hours of transportation, theexpression rate reached the peak about 18% when CY was injected 18 hours, and then the ratereduced gradually.Finally, peptidoglycan (PG) was used to counteract immunity inhibition of CY, expressionrate of GFP under this condition was observed. These all could prove the effect of GFP in thismodel and the application of the model. Before transportation and CY injection, 25mg per kgdose of PG per mouse per day was injected 3 days continually. There was obvious difference(P<0.05) between PG-CY-treated mice and CY-treated mice, GFP+ cell number, total cellnumber and the percent of GFP+ cell being separately 1.63, 1.26, 1.29 times of CY-treated mice;But compared to control, the difference was also obvious (P<0.05), the three parameters beingrespectively 0.629, 0.766 and 0.821.