Existence of proviral porcine endogenous retrovirus in fresh and decellularised porcine tissues

Abstract

Purpose: Swine are expected to be utilized as xenograft donors for both whole organ and cellular transplantation. A major concern in using porcine organs for transplantation is the potential of transmission of porcine endogenous retrovirus (PERV). Tissue-engineered or decellularised heart valves have already been implanted in humans and have been marketed by certain companies after Food and Drug Administration (FDA) approval. The aim of this study was to examine the existence of porcine endogenous retrovirus (PERV) in fresh and decellularised porcine tissues. Methods: Porcine tissues (both fresh and decellularised) were analysed using validated assays speciÞ c for PERV: polymerase chain reaction (PCR), reverse transcriptase polymerase chain reaction (RT-PCR). Results: PERV speciÞ c GAG sequences were found in the porcine heart tissue samples using PCR for DNA and RT-PCR for RNA. All tissue samples (both fresh and treated tissues) like aortic valve, pulmonary valve and heart muscle showed the presence of PERV DNA. RT PCR for PERV was positive in all fresh tissues and was found to be negative in decellularised treated tissues. Conclusions: PCR is a rapid, speciÞ c test for the detection of PERV virus in xenografts. These Þ ndings have demonstrated that the presence of proviral DNA form of PERV in porcine tissues needs to be carefully considered when the infectious disease potential of xenotransplantation is being assessed.

An Alternative Approach to Decellularize Whole Porcine Heart

“…What quantities of ECM proteins or growth factors are required for successful recellularization is also not known. Another shortcoming of our study is the question, whether the porcine matrix carries potential immunogenic reactions and infectious risks through the transmission of porcine endogenous retrovirus 48 or α-Gal epitopes. For this reason, further studies are required to confirm or exclude these obstacles.…”

A review of cellularization strategies for tissue engineering of whole organs

“…However, inadequate removal of xenoantigens has the potential to elicit an immune response upon implantation (Simon et al, 2003 ; Kasimir et al, 2006 ; Bastian et al, 2008 ; Cicha et al, 2011 ; Keane et al, 2012 ). In addition, there are conflicting reports about the transmission of PERV from porcine matrices (Kallenbach et al, 2004 ; Prabha and Verghese, 2008 ).…”

Porcine Endogenous Retroviruses in Xenotransplantation—Molecular Aspects

“…Paradis et al [ 17 ] and Sypniewski et al [ 47 ] used PCR primers situated in a highly conserved region of the PERV genome, the gag sequence, to detect all PERV types in both human and porcine samples, respectively. In addition, Prabha and Verghese [ 49 , 84 ], with the use of PCR for PERV DNA and reverse transcriptase RT-PCR for PERV RNA analyses, found PERV-specific gag sequences in aortic valve, pulmonary valve, and heart muscle samples obtained from fresh porcine xenograft tissue. Kim et al [ 85 ] detected PERV gag sequences in porcine cells by PCR to assess the usefulness of the one-step extraction method compared to the phenol extraction method, whereas Wang et al [ 86 ] assessed the safety of a bioartificial liver support system.…”

“…Detection of these genes in the test material indicates the presence of PERVs, but it does not indicate which subtype of the virus is present. Generally, it answers the question as to whether the material being tested contains genetic material of PERV origin [ 23 , 47 , 49 , 84 , 85 , 86 , 87 , 88 ]. The second group consists of primers complementary to env , a gene that is characterized by a large degree of variability.…”