Immunology Research Of Isotype Blood Vessel Transplantation Of Late Pregnancy Fetal Goat Freezed In The Liquid Nitrogon

Objective With the rapid development of neonatal cardiac surgery recently, the request to finding suitable replacement material of heart valve and vascular homografts becomes more and more urgent.The experiment is aimed to provide theroical foundation of animal research,which is to establish homografts bank of valved great arteries from late-pregnancy fetus.Methods The experiment animals consist of ten pregnant goats (gestational age 3~4 mons) and seventeen lambs(2~3 mons).Take out of the fetus under sterile. Twenty aortas are obtained from the fetus, which are clipped under sterile. These fetus are divided into three groups. The first group is fresh(n=8),which is implanted to the lamb's peripheral artery directly. The second group is soaked in cryoprotectant No. 1 and No.2 sequentially, then equilibrated in 4℃ refrigerator, packed in special freezing bags. Programmed reducing the temperature is finished by using gradient reducing the temperature of liquid nitrogen vapor. The homograftes are preserved for one month at -196℃.Then they are rewarmed in the warm water quickly and implanted to lamb's peripheral artery. The leaf is the control group. Estimate the IgG in the tissue by immunohistochemistry method. Evaluate the immunologic change before and after the implantation.Results Seventeen aortas are transplanted, sixteen lambs survive. The survive rage is 94%.The fresh group and freezing group are estimated by immunohistrochemistry sequentially. The results show that IgG main deposition in the media of vessel, and stained in the plasm. The two groups both show statistical significance contrast with the control group in one and four months group. Contrast with four month group, one month group show statistical significance in the fresh group while not in the freezing group.Conclusions The blood vessel transplantation in the goat's great vessel shows high survive rate. The vessel after freezing still remains immunogenicity,but lower than the fresh group. With the time going the immunogenicity will show the descent tendency.