title: Adipose-derived mesenchymal stromal cells from genetically modified pigs: immunogenicity and immune modulatory properties.
abstract: OBJECTIVE
  The immunomodulatory and anti-inflammatory effects of mesenchymal stromal cells (MSC) could prove to be a potential therapeutic approach for prolongation of survival of cell xenotransplantation. Adipose (Ad) MSC from genetically modified pigs could be an abundant source of pig donor-specific MSC.
  
  
  METHODS
  Pig (p) MSC were isolated from adipose tissue of α1,3-galactosyltransferase gene knock-out pigs transgenic for human (h) CD46 (GTKO/hCD46), a potential source of islets. After characterization with differentiation and flow cytometry (FCM), AdMSC were compared with bone marrow (BM) MSC of the same pig and human adipose-derived (hAd) MSC. The modulation of human peripheral blood mononuclear cell (hPBMC) responses to GTKO pig aortic endothelial cells (pAEC) by different MSC was compared by measuring 3H-thymidine uptake. The supernatants from the AdMSC cultures were used to determine the role of soluble factors.
  
  
  RESULTS
  GTKO/hCD46 pAdMSC (i) did not express galactose-α1,3-galactose (Gal) but expressed hCD46, (ii) differentiated into chondroblasts, osteocytes and adipocytes, (iii) expressed stem cell markers, (iv) expressed lower levels of Swine Leucocyte Antigen I (SLAI), Swine Leucocyte Antigen II DR (SLAIIDR) and CD80 than pAEC before and after pig interferon (IFN)-γ stimulation. The proliferative responses of hPBMC to GTKO/hCD46 pAdMSC and hAdMSC stimulators were similar, and both were significantly lower than to GTKO pAEC (P < 0.05). The proliferation of hPBMC to GTKO pAEC was equally suppressed by GTKO/hCD46 pAdMSC and hAdMSC (P > 0.05). The supernatant from GTKO/hCD46 pAdMSC did not suppress the human xenoresponse to GTKO pAEC, which was cell-cell contact-dependent.
  
  
  CONCLUSIONS
  Initial evidence suggests that genetically modified pAdMSC function across the xenogeneic barrier and may have a role in cellular xenotransplantation.
authors.affiliation: Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania 15261, USA.
authors.forename: Goutham
authors.initials: G
authors.lastname: Kumar
authors.forename: Hidetaka
authors.initials: H
authors.lastname: Hara
authors.forename: Cassandra
authors.initials: C
authors.lastname: Long
authors.forename: Humza
authors.initials: H
authors.lastname: Shaikh
authors.forename: David
authors.initials: D
authors.lastname: Ayares
authors.forename: David K C
authors.initials: DK
authors.lastname: Cooper
authors.forename: Mohamed
authors.initials: M
authors.lastname: Ezzelarab
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D030801:Animals, Genetically Modified; D002454:Cell Differentiation / Q000235:genetics / Q000502:physiology; D002478:Cells, Cultured; D005700:Galactosyltransferases / Q000235:genetics / Q000378:metabolism; D006801:Humans; D008214:Lymphocytes / Q000166:cytology / Q000378:metabolism; D045164:Mesenchymal Stem Cell Transplantation; D059630:Mesenchymal Stem Cells / Q000166:cytology* / Q000378:metabolism; D013552:Swine
chemical_list: D005700:Galactosyltransferases