Is it currently possible to evaluate the risk posed by PERVs for clinical xenotransplantation?

Expression profile of human porcine endogenous retrovirus A receptors (HuPAR‐1, HuPAR‐2) and transcription factor activator protein‐2γ (TFAP‐2C) genes in infected human fibroblasts—Model in vitro

“…Genetically modified domestic pigs ( Sus scrofa domestica ) seem to be the most promising source of xenogenic tissues mainly because of the ease of breed and physiology similar to human . However, the use of porcine tissues for xenotransplantation raises concerns, especially in the context of the potential interspecies transmission of porcine endogenous retroviruses (PERVs) …”

“…1,2 However, the use of porcine tissues for xenotransplantation raises concerns, especially in the context of the potential interspecies transmission of porcine endogenous retroviruses (PERVs). 3 Recently implemented CRISPR-Cas9 technology of gene edition may be able to eliminate the risk posed by PERVs; however, the risk of xenozoonosis with other viruses remains. 4,5 PERVs are integrated within the genome of all pigs.…”

Are there better assays to evaluate the risk of transmission of porcine endogenous retroviruses (PERVs) to human cells?

“…2,3 Analysing all data on PERV infection in vitro and in vivo, it is apparent that there are no further experimental opportunities to evaluate the potential risk posed by PERVs until we move to the clinic. 4 Currently, the gold standard for assessing the risk of PERV transmission from porcine cells, tissues or organs is to use the complex HEK293 co-incubation assay. Here, we would like to invite discussion on proposed cheaper and less time-consuming alternatives to the HEK293 co-incubation PERV assay.…”

Standardization of the proceedings for preparing clinical trials of corneal xenotransplantation in South Korea

“…These requirements may be a good reference for clinical trials in each country and may be modified in subsequent clinical trials according to the results of the initial clinical trial. Noteworthy, the safety aspect of monitoring for PERV transmission cannot be addressed in NHP xenotransplantation models as the PERV receptor in rhesus, cynomolgus macaques and baboons is not functional . Hence, it does not make sense to include the monitoring for PERV transmission in preclinical studies using NHP models.…”

“…[12][13][14][15] National Bioethics Committee will review any developed clinical trial protocols, and a legislative bill for the support and management of advanced regenerative medicine is pending at the Korean National Assembly. 19 Hence, it does not make sense to include the monitoring for PERV transmission in preclinical studies using NHP models. Clinical trials seem to be essential to answer questions about this issue although many of the assays are not available and have not been shown to be suitable in clinical trials.…”