BACKGROUND: Embryonic pancreatic tissue is characterized by its abundance, potent in proliferation & differentiation, and minimal immunological rejection. It is widely considered as potential pancreatic endocrinological stem cells resource for treating diabetes mellitus.OBJECTIVE: To investigate the embryonic mouse pancreatic tissue isolation technique and observe the recipients' blood glucose regulatory effects of the grafted embryonic pancreas in an experimental diabetes mellitus mouse model.METHODS: Pancreatic tissue from C57B1/6 mouse embryos at embryonic days 11.5-16.5 was isolated under the stereomicroscope. C57BL/6 mouse models of streptozocin-induced diabetes mellitus were established and then randomly divided into two groups: transplantation group, in which, five pieces of pancreatic tissue of mice at embryonic 16.5 days were transplanted into mouse renal capsule, and sham-operated control group, in which, 0.05 mL RPMI1640 culture medium was injected into mouse renal capsule. When blood glucose level of the transplantation group mouse was≤ 11.2 mmol/L, the endocrine function of embryonic pancreatic tissue transplanted was detected by IPGTT and IPITT methods and then the transplanted graft was removed for observing the blood glucose relapse.RESULTS AND CONCLUSION: Nearly intact pancreatic tissue of mice at embryonic days 11.5-16.5 could be isolated through the use of stereomicroscope. Pancreatic tissue morphology and color of mice ≤ embryonic 12.5 days were difficultly distinguished from adjacent tissue and they could only be isolated carefully according to the relationship with adjacent organs. Pancreatic tissue of mice > embryonic 12.5 days exhibited initial endocrinological tissue morphology mimic white cauliflower. Histological and ELISA examinations showed that embryonic pancreatic tissue could express and secrete insulin and the insulin level was gradually increased with developmental time. Embryonic pancreatic tissue could grow beneath the recipient renal capsule. The insulin and glucagon expression in the post-transplantational pancreatic tissue graft was increased compared with prior to transplantation. These results suggest that pancreatic tissue is a potential stem cell resource for treating the diabetes mellitus.

Objective To analyze the practicability of using ELISA kit for the detection of hepati-tis E virus antigen ( HEV-Ag) in plasma donations and Biomex HEV seroconversion panels. Methods The HEV-Ag positive samples were screened out from 36 340 donated blood plasma samples. Real-time fluores-cent PCR was performed for the detection of HEV RNA in HEV-Ag positive samples. The open reading frame 2 (ORF2) in HEV RNA was amplified by nested RT-PCR and the amplified products were confirmed by sequencing analysis. Phylogenetic tree was constructed for HEV genotyping. Five Biomex HEV serocon-version panels were used in this study for the detection of HEV-Ag, anti-HEV antibody and HEV RNA as well as the correlation analysis between HEV-Ag and HEV RNA. Results Twenty-six out of 36 340 plasma samples (0. 07%) were positive for HEV-Ag. Of the 26 samples, 25 samples were positive for HEV RNA as indicated by the results of nested RT-PCR and 23 positive samples were confirmed by sequencing analysis. The positive rate of HEV RNA in blood plasma donators was 1 ∶ 1 580 (0. 06%). There were 17 samples of genotype 1 (74%) and 6 samples of genotype 4 (26%) according to the phylogenetic tree analysis. All of the HEV-Ag positive samples were also positive for HEV RNA as indicated by the analysis of Biomex sero-conversion panels. HEV-Ag was consistent with the peak of the HEV RNA concentration. Conclusion A close relationship between HEV-Ag and HEV RNA was observed. HEV-Ag screening could be used as a measure to reduce the risk of HEV transmission by blood transfusion.