Chapter 2: Source pigs

Abstract

An islet xenotransplantation product includes live cells from a non-human source, in this study, a pig source. A live product cannot be subjected to conventional disinfection, and therefore the source pig must be depleted of infectious agents that can transmit to the recipient and cause disease. Among other requirements, regulatory guidances specify that donor animals fulfill the designated pathogen-free (DPF) status. Donor pigs fulfilling DPF status are generally bred and maintained in biosecure facilities, where they are shielded from the outside by filtered air, disinfected water, and irradiated food that is certified free of any mammalian protein. All materials are autoclaved upon entry, and personnel enter by shower-in/shower-out, and are wearing special clothes. The operation of such facilities is in compliance with Current Good Manufacturing Practices. To ensure DPF status, pigs are brought into such facilities via Cesarean section, and the source pigs are kept as a closed herd. The DPF status cannot be realized for endogenous viruses, such as porcine endogenous retrovirus. Therefore, regulatory authorities require patient monitoring after xenotransplantation. Considering the infectious pathogen status and necessary regulatory compliance, it is recommended that organ procurement be conducted at the animal facility and that cell manufacturing facilities be located nearby. To enable assessment of as-yet unknown pathogens long after xenotransplantation, regulatory guidances mandate archiving donor materials for at least 50 yr. As this is essentially a public health issue, governmental institutions are urged to be responsible for the archive.