[A preliminary research on the exosome influenced by virus infection in the renal transplantation recipients].

ABSTRACT

Objective: Virus infection is a common complication of transplantation.With the research and application of exosome is becoming more popular, this study focused on whether the virus particles and nucleic acids exist in the exosomes extracted from the plasma of recipients with virus infection after renal transplantation. Methods: A total of 10 independent transplantation recipients at Institute of Organ Transplantation, 309th Hospital of Chinese People's Liberation Army from January 2015 to July 2017 were studied in this study.5 cases of positive or suspected positive in granulocytes HCMV pp65 antigen detection and positive in plasma HCMV DNA test, and the other 5 cases of positive results in plasma BK DNA test were adopted.Exosomes were extracted from the collected plasma samples with SBI kit.Electron microscopy and nanoparticles tracing analyzer (NTA) were used for exosome analysis.Quantitative real-time PCR method was used to inspect and compare virus DNA copies number in plasma, exosome and effluent. Results: Typical exosome-like vesicle structure was observed.NTA put forward the sample concentration data from 1.2 to 4.5×10(12) particles/ml, and the particle diameters were 30-200 nm.In the qRT-PCR assays, the viral DNA quantitative results of exosome samples are lower but on the same magnitude compared with that of the plasma, and sharply decreased in effluent. Conclusions: Virus DNAs in exosome samples of recipients with viral infection after transplantation were detected in great quantities.This not only hints the spread of the virus may take advantage of the biological formation process of exosomes, but also warns that the limitation of the existing way to extract exosmes from virus infected population may be a bottleneck in research.