Inactivation of porcine endogenous retrovirus in pigs using CRISPR-Cas9.
Level 5 - mechanism / opinion, no new human data
Preclinical bench and animal genetic engineering study
PubMed 28798043 · doi:10.1126/science.aan4187
What was done
Researchers evaluated the infectivity and horizontal transmission of porcine endogenous retroviruses (PERVs) in human cells. Using CRISPR-Cas9 genome editing, they inactivated all PERVs in a primary porcine cell line and generated PERV-inactivated pigs using somatic cell nuclear transfer.
What was found
The authors confirmed that PERVs can infect human cells and horizontally transfer between them. They achieved complete inactivation of PERVs in primary pig cells and successfully produced live PERV-inactivated pigs. No specific quantitative data (such as PERV copy numbers, editing efficiency percentages, or animal counts) were reported in the abstract.
Why it matters
Transmission of porcine endogenous retroviruses to humans represents a primary biosafety concern for pig-to-human xenotransplantation. This study demonstrates the technical feasibility of generating viable pigs completely devoid of active PERVs to improve xenotransplantation safety.
Limits
The abstract provides no sample size, survival rates, or quantitative metrics. As a preclinical animal and cell culture study, it does not demonstrate in vivo human safety, long-term organ functionality, or immunological compatibility.
Cited by
- supports Porcine endogenous retroviruses (PERVs) are present in the germline genome of all pigs and have been shown to infect and replicate in human cells in vitro.