title: Immunologic properties of human fetal mesenchymal stem cells.
abstract: OBJECTIVE
  Mesenchymal stem cells (MSCs) can be isolated from adult bone marrow and fetal liver. We investigated the immunologic properties of undifferentiated and differentiated human fetal MSCs.
  
  
  METHODS
  Expression of HLA class I and II was investigated by flow cytometry and Western blot on undifferentiated fetal MSC and after in vitro differentiation to adipocytes and osteocytes. Alloreactivity was studied after adding fetal MSCs to allogeneic lymphocytes in mixed lymphocyte cultures.
  
  
  RESULTS
  Fetal MSCs expressed HLA class I but not HLA class II. The presence of interferon gamma (IFN-gamma) in the growth medium for 2 days initiated the intracellular synthesis of HLA class II, but 7 days of exposure was required for cell surface expression. Neither undifferentiated nor differentiated fetal MSCs induced proliferation of allogenic lymphocytes. Fetal MSCs treated with IFN-gamma suppressed alloreactive lymphocytes.
  
  
  CONCLUSIONS
  Undifferentiated and differentiated fetal MSCs do not elicit alloreactive lymphocyte proliferation. The results suggest that fetal MSCs have potentials for allogenic transplantation.
authors.affiliation: Division of Clinical Immunology, Karolinska Institutet, Huddinge University Hospital, Stockholm, Sweden. Cecelia.Gotherstrom@labmed.ki.se
authors.forename: Cecilia
authors.initials: C
authors.lastname: Götherström
authors.forename: Olle
authors.initials: O
authors.lastname: Ringdén
authors.forename: Charlotte
authors.initials: C
authors.lastname: Tammik
authors.forename: Eva
authors.initials: E
authors.lastname: Zetterberg
authors.forename: Magnus
authors.initials: M
authors.lastname: Westgren
authors.forename: Katarina
authors.initials: K
authors.lastname: Le Blanc
mesh_terms: D017667:Adipocytes / Q000276:immunology; D002454:Cell Differentiation; D002478:Cells, Cultured; D003470:Culture Media; D015395:Histocompatibility Antigens Class I / Q000032:analysis; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D006801:Humans; D007371:Interferon-gamma / Q000008:administration & dosage; D008099:Liver / Q000196:embryology; D007959:Lymphocyte Culture Test, Mixed; D008648:Mesoderm / Q000166:cytology / Q000276:immunology*; D010011:Osteocytes / Q000276:immunology; D013234:Stem Cells / Q000166:cytology / Q000276:immunology*
chemical_list: D003470:Culture Media; D015395:Histocompatibility Antigens Class I; D000949:Histocompatibility Antigens Class II; D007371:Interferon-gamma