BACKGROUND: Genetically modified pigs are a promising potential source of lung xenografts. Ex vivo xenoperfusion is an effective platform for testing the effect of new modifications, but typical experiments are limited by testing of a single genetic intervention and small sample sizes. The purpose of this study was to analyze the individual and aggregate effects of donor genetic modifications on porcine lung xenograft survival and injury in an extensive pig lung xenoperfusion series. METHODS: Data from 157 porcine lung xenoperfusion experiments using otherwise unmodified heparinized human blood were aggregated as either continuous or dichotomous variables. Lungs were wild type in 17 perfusions (11% of the study group), while 31 lungs (20% of the study group) had one genetic modification, 40 lungs (39%) had 2, and 47 lungs (30%) had 3 or more modifications. The primary endpoint was functional lung survival to 4 h of perfusion. Secondary analyses evaluated previously identified markers associated with known lung xenograft injury mechanisms. In addition to comparison among all xenografts grouped by survival status, a subgroup analysis was performed of lungs incorporating the GalTKO.hCD46 genotype. RESULTS: Each increase in the number of genetic modifications was associated with additional prolongation of lung xenograft survival. Lungs that exhibited survival to 4 h generally had reduced platelet activation and thrombin generation. GalTKO and the expression of hCD46, HO-1, hCD55, or hEPCR were associated with improved survival. hTBM, HLA-E, and hCD39 were associated with no significant effect on the primary outcome. CONCLUSION: This meta-analysis of an extensive lung xenotransplantation series demonstrates that increasing the number of genetic modifications targeting known xenogeneic lung injury mechanisms is associated with incremental improvements in lung survival. While more detailed mechanistic studies are needed to explore the relationship between gene expression and pathway-specific injury and explore why some genes apparently exhibit neutral (hTBM, HLA-E) or inconclusive (CD39) effects, GalTKO, hCD46, HO-1, hCD55, and hEPCR modifications were associated with significant lung xenograft protection. This analysis supports the hypothesis that multiple genetic modifications targeting different known mechanisms of xenograft injury will be required to optimize lung xenograft survival.
BACKGROUND: Genetically modified pigs are a promising potential source of lung xenografts. Ex vivo xenoperfusion is an effective platform for testing the effect of new modifications, but typical experiments are limited by testing of a single genetic intervention and small sample sizes. The purpose of this study was to analyze the individual and aggregate effects of donor genetic modifications on porcine lung xenograft survival and injury in an extensive pig lung xenoperfusion series. METHODS: Data from 157 porcine lung xenoperfusion experiments using otherwise unmodified heparinized human blood were aggregated as either continuous or dichotomous variables. Lungs were wild type in 17 perfusions (11% of the study group), while 31 lungs (20% of the study group) had one genetic modification, 40 lungs (39%) had 2, and 47 lungs (30%) had 3 or more modifications. The primary endpoint was functional lung survival to 4 h of perfusion. Secondary analyses evaluated previously identified markers associated with known lung xenograft injury mechanisms. In addition to comparison among all xenografts grouped by survival status, a subgroup analysis was performed of lungs incorporating the GalTKO.hCD46 genotype. RESULTS: Each increase in the number of genetic modifications was associated with additional prolongation of lung xenograft survival. Lungs that exhibited survival to 4 h generally had reduced platelet activation and thrombin generation. GalTKO and the expression of hCD46, HO-1, hCD55, or hEPCR were associated with improved survival. hTBM, HLA-E, and hCD39 were associated with no significant effect on the primary outcome. CONCLUSION: This meta-analysis of an extensive lung xenotransplantation series demonstrates that increasing the number of genetic modifications targeting known xenogeneic lung injury mechanisms is associated with incremental improvements in lung survival. While more detailed mechanistic studies are needed to explore the relationship between gene expression and pathway-specific injury and explore why some genes apparently exhibit neutral (hTBM, HLA-E) or inconclusive (CD39) effects, GalTKO, hCD46, HO-1, hCD55, and hEPCR modifications were associated with significant lung xenograft protection. This analysis supports the hypothesis that multiple genetic modifications targeting different known mechanisms of xenograft injury will be required to optimize lung xenograft survival.
Authors: Emanuele Cozzi; Conrad Vial; Daniel Ostlie; Bhatti Farah; Gilda Chavez; Kenneth G C Smith; John R Bradley; Sathia Thiru; Hugh F S Davies; John Wallwork; David J G White; Martin Goddard; Peter J Friend Journal: Xenotransplantation Date: 2003-07 Impact factor: 3.907
Authors: Donald G Harris; Kevin J Quinn; Siamak Dahi; Lars Burdorf; Agnes M Azimzadeh; Richard N Pierson Journal: Xenotransplantation Date: 2014-07-05 Impact factor: 3.907
Authors: A Azimzadeh; G L Zorn; K S A Blair; J P Zhang; S Pfeiffer; R A Harrison; E Cozzi; D J G White; R N Pierson Journal: Xenotransplantation Date: 2003-03 Impact factor: 3.907
Authors: D K Cooper; A M Keogh; J Brink; P A Corris; W Klepetko; R N Pierson; M Schmoeckel; R Shirakura; L Warner Stevenson Journal: J Heart Lung Transplant Date: 2000-12 Impact factor: 10.247
Authors: Carsten Schröder; Steffen Pfeiffer; Guosheng Wu; George L Zorn; Li Ding; Catherine Allen; Richard A Harrison; David J G White; Agnes M Azimzadeh; Richard N Pierson Journal: J Heart Lung Transplant Date: 2003-12 Impact factor: 10.247
Authors: Carol J Phelps; Chihiro Koike; Todd D Vaught; Jeremy Boone; Kevin D Wells; Shu-Hung Chen; Suyapa Ball; Susan M Specht; Irina A Polejaeva; Jeff A Monahan; Pete M Jobst; Sugandha B Sharma; Ashley E Lamborn; Amy S Garst; Marilyn Moore; Anthony J Demetris; William A Rudert; Rita Bottino; Suzanne Bertera; Massimo Trucco; Thomas E Starzl; Yifan Dai; David L Ayares Journal: Science Date: 2002-12-19 Impact factor: 47.728
Authors: Bruce E Loveland; Julie Milland; Peter Kyriakou; Bruce R Thorley; Dale Christiansen; Marc B Lanteri; Mark Regensburg; Maureen Duffield; Andrew J French; Lindsay Williams; Louise Baker; Malcolm R Brandon; Pei-Xiang Xing; Del Kahn; Ian F C McKenzie Journal: Xenotransplantation Date: 2004-03 Impact factor: 3.907
Authors: D M Kulick; C T Salerno; A P Dalmasso; S J Park; M G Paz; W L Fodor; R M Bolman Journal: J Thorac Cardiovasc Surg Date: 2000-04 Impact factor: 5.209
Authors: Agnes M Azimzadeh; Sean S Kelishadi; Mohamed B Ezzelarab; Avneesh K Singh; Tiffany Stoddard; Hayato Iwase; Tianshu Zhang; Lars Burdorf; Evelyn Sievert; Chris Avon; Xiangfei Cheng; David Ayares; Keith A Horvath; Philip C Corcoran; Muhammad M Mohiuddin; Rolf N Barth; David K C Cooper; Richard N Pierson Journal: Xenotransplantation Date: 2015-07-14 Impact factor: 3.907
Authors: Beth M French; Selin Sendil; Krishna Mohan Sepuru; Jolene Ranek; Lars Burdorf; Donald Harris; Emily Redding; Xiangfei Cheng; Christopher T Laird; Yuming Zhao; Benjamin Cerel; Krishna Rajarathnam; Richard N Pierson; Agnes M Azimzadeh Journal: Xenotransplantation Date: 2018-02-09 Impact factor: 3.907
Authors: Hayato Iwase; Hong Liu; Martin Wijkstrom; Huidong Zhou; Jagjit Singh; Hidetaka Hara; Mohamed Ezzelarab; Cassandra Long; Edwin Klein; Robert Wagner; Carol Phelps; David Ayares; Ron Shapiro; Abhinav Humar; David K C Cooper Journal: Xenotransplantation Date: 2015-06-29 Impact factor: 3.907