학술논문
Immunological and functional features of decellularized xenogeneic heart valves after transplantation into GGTA1-KO pigs
Research Article
Research Article
Document Type
Academic Journal
Author
Source
Regenerative Biomaterials. October 2021, Vol. 8 Issue 5, p1#, 12 p.
Subject
Language
English
Abstract
Introduction Recent advances in genetic engineering of pigs, improved immunosuppressive treatments and organ preservation techniques have enabled a resurgence of xenotransplantation, i.e. the live supporting discordant transplantation of porcine hearts [...]
Decellularization of xenogeneic heart valves might lead to excellent regenerative implants, from which many patients could benefit. However, this material carries various xenogeneic epitopes and thus bears a considerable inherent immunological risk. Here, we investigated the regenerative and immunogenic potential of xenogeneic decellularized heart valve implants using pigs deficient for the galactosyltransferase gene (GGTA1-KO) as novel large animal model. Decellularized aortic and pulmonary heart valves obtained from sheep, wild-type pigs or GGTA1-KO pigs were implanted into GGTA1-KO pigs for 3, or 6 months, respectively. Explants were analyzed histologically, immunhistologically (CD3, CD21 and CD172a) and anti-[alpha]Gal antibody serum titers were determined by ELISA. Xenogeneic sheep derived implants exhibited a strong immune reaction upon implantation into GGTA1-KO pigs, characterized by massive inflammatory cells infiltrates, presence of foreign body giant cells, a dramatic increase of anti-[alpha]Gal antibody titers and ultimately destruction of the graft, whereas wild-type porcine grafts induced only a mild reaction in GGTA1-KO pigs. Allogeneic implants, wild-type/wild-type and GGTA1-KO/GGTA1-KO valves did not induce a measurable immune reaction. Thus, GGTA1-KO pigs developed a 'human-like' immune response toward decellularized xenogeneic implants showing that immunogenicity of xenogeneic implants is not sufficiently reduced by decellularization, which detracts from their regenerative potential. Keywords: [alpha]Gal-KO pig; decellularization; heart valves; xenoantibodies; large animal model
Decellularization of xenogeneic heart valves might lead to excellent regenerative implants, from which many patients could benefit. However, this material carries various xenogeneic epitopes and thus bears a considerable inherent immunological risk. Here, we investigated the regenerative and immunogenic potential of xenogeneic decellularized heart valve implants using pigs deficient for the galactosyltransferase gene (GGTA1-KO) as novel large animal model. Decellularized aortic and pulmonary heart valves obtained from sheep, wild-type pigs or GGTA1-KO pigs were implanted into GGTA1-KO pigs for 3, or 6 months, respectively. Explants were analyzed histologically, immunhistologically (CD3, CD21 and CD172a) and anti-[alpha]Gal antibody serum titers were determined by ELISA. Xenogeneic sheep derived implants exhibited a strong immune reaction upon implantation into GGTA1-KO pigs, characterized by massive inflammatory cells infiltrates, presence of foreign body giant cells, a dramatic increase of anti-[alpha]Gal antibody titers and ultimately destruction of the graft, whereas wild-type porcine grafts induced only a mild reaction in GGTA1-KO pigs. Allogeneic implants, wild-type/wild-type and GGTA1-KO/GGTA1-KO valves did not induce a measurable immune reaction. Thus, GGTA1-KO pigs developed a 'human-like' immune response toward decellularized xenogeneic implants showing that immunogenicity of xenogeneic implants is not sufficiently reduced by decellularization, which detracts from their regenerative potential. Keywords: [alpha]Gal-KO pig; decellularization; heart valves; xenoantibodies; large animal model