Porcine Endogenous Retrovirus (PERV) Infection of HEK-293 Cell Line Alters Expression of Human Endogenous Retrovirus (HERV-W) Sequences

摘要

The risk of infections of human recipientsafter xenotransplantations is now mainly represented by porcine endogenous retroviruses (PERVs) asthese particles are part of the porcine genome. As inall vertebrates, human genome harbours its own numerous genetic sequences of retroviral origin; it isestimated that they comprise about 8 % of the human genome. Because some of them play an important role in human physiology, it is valuable to estimate whether the presence of PERVs in human cellsinfluences homeostasis of the human endogenousretrovirus (HERV) expression pattern. The aim ofthe study was to evaluate whether the expressionprofile of HERV-W genes changes after infection ofcells by porcine endogenous retroviruses. In the experimental settings, human embryonic kidney cellline (HEK-293) was infected by PERV particles andcultivated up to 22th passage after infection. HERV-Wgag, pol and env, as well as env from locus 7q21.2gene expression was monitored by means of realtime reverse transcription-quantitative polymerasechain reaction (RT-qPCR) and Western blot techniques. We found that the expression level ofHERV-W genes differs in PERV-infected HEK-293cell cultures in comparison with that from non-infected cultures. Relative HERV-W gene expressionalso differed significantly between particular passages (P < 0.05). Moreover, we have noticed a highcorrelation between the HERV-W Env(7q21.2)mRNA and protein level (Spearman rank r = 0.65;P < 0.05) during the course of the experiment. Aspreviously hypothesized, human genomic sequencesof retroviral origin may be changed by the presenceof porcine endogenous retroviruses.