Knockdown of porcine endogenous retrovirus (PERV) expression by PERV-specific shRNA in transgenic pigs.
BACKGROUND
Xenotransplantation using porcine cells, tissues or organs may be associated with the transmission of porcine endogenous retroviruses (PERVs). More than 50 viral copies have been identified in the pig genome and three different subtypes of PERV were released from pig cells, two of them were able to infect human cells in vitro. RNA interference is a promising option to inhibit PERV transmission.


METHODS
We recently selected an efficient si (small interfering) RNA corresponding to a highly conserved region in the PERV DNA, which is able to inhibit expression of all PERV subtypes in PERV-infected human cells as well as in primary pig cells. Pig fibroblasts were transfected using a lentiviral vector expressing a corresponding sh (short hairpin) RNA and transgenic pigs were produced by somatic nuclear transfer cloning. Integration of the vector was proven by PCR, expression of shRNA and PERV was studied by in-solution hybridization analysis and real-time RT PCR, respectively.


RESULTS
All seven born piglets had integrated the transgene. Expression of the shRNA was found in all tissues investigated and PERV expression was significantly inhibited when compared with wild-type control animals.


CONCLUSIONS
This strategy may lead to animals compatible with PERV safe xenotransplantation.
Dieckhoff
Britta
B
Robert Koch Institute, Berlin, Germany.
Petersen
Björn
B
Kues
Wilfried A
WA
Kurth
Reinhard
R
Niemann
Heiner
H
Denner
Joachim
J
D000818:Animals; D030801:Animals, Genetically Modified; D002478:Cells, Cultured; D005347:Fibroblasts / Q000166:cytology / Q000502:physiology; D006801:Humans; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism*; D012190:Retroviridae / Q000235:genetics / Q000378:metabolism; D013552:Swine; D014183:Transplantation, Heterologous
D034741:RNA, Small Interfering