title: Adipose-derived stromal cells cultured in a low-serum medium, but not bone marrow-derived stromal cells, impede xenoantibody production.
abstract: BACKGROUND
  Although the immunomodulatory effects of mesenchymal stromal cells (MSC) on T cells have been elucidated, little is known about their effects on B cells. Recently, we have established a novel culture method for adipose-derived MSC (ASC) using low (2%) serum medium containing fibroblast growth factor-2. We showed that low serum-cultured ASC (LASC) was superior to high (20%) serum-cultured ASC (HASC) when used in regenerative therapy. The aim of this study was to compare the action of LASC, HASC, and bone marrow-derived MSC (BM-MSC), on xenoantibody production by B cells.
  
  
  METHODS
  Adipose-derived mesenchymal stromal cells and BM-MSC were obtained from humans or F344 rats and expanded in a low-serum or a high-serum culture medium. Proliferation of human peripheral mononuclear cells (PBMC) or rat splenocytes was induced by phytohemagglutinin (PHA) or anti-IgM-antibody. These cells were then co-cultured with LASC, HASC, or BM-MSC, and cell proliferation was studied. Porcine red blood cells (pRBC) were intraperitoneally injected into Lewis rats, and LASC, HASC, or BM-MSC obtained from F344 rats were injected intravenously or intraperitoneally. The levels of antibodies (IgM and IgG) against pRBC were examined using flow cytometry.
  
  
  RESULTS
  Human LASC suppressed PBMC proliferation more effectively than human HASC. Human LASC suppressed both T-cell and B-cell proliferation when incubated with PHA (a T-cell stimulus). However, human LASC did not suppress B-cell proliferation after incubation with anti-IgM-antibody (a T-cell-independent stimulus). Rat LASC suppressed PHA-stimulated splenocyte proliferation more effectively than rat HASC or rat BM-MSC. In vivo studies showed that intravenous injection of rat LASC significantly reduced the levels of IgG antibodies against pRBC, while intravenous administration of the other two types of MSC (rat HASC or rat BM-MSC) or intraperitoneal administration of rat LASC did not impede IgG production. A significant number of LASC were observed in the spleen when injected intravenously while only a few LASC were observed when given intraperitoneally.
  
  
  CONCLUSIONS
  Administration of LASC effectively impeded xenoantibody production by B cells through the inhibition of T-cell function, while HASC or BM-MSC showed less promising effects. These results suggest that intravenous injection of LASC may be useful in attenuating antibody-mediated rejection.
authors.affiliation: Department of Nephrology, Nagoya University Graduate School of Medicine Department of Applied Immunology, Nagoya University School of Medicine, 65 Tsurumai-cho Showaku, Nagoya, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Saka
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Furuhashi
authors.forename: Takayuki
authors.initials: T
authors.lastname: Katsuno
authors.forename: Hangsoo
authors.initials: H
authors.lastname: Kim
authors.forename: Takenori
authors.initials: T
authors.lastname: Ozaki
authors.forename: Kenta
authors.initials: K
authors.lastname: Iwasaki
authors.forename: Masataka
authors.initials: M
authors.lastname: Haneda
authors.forename: Waichi
authors.initials: W
authors.lastname: Sato
authors.forename: Naotake
authors.initials: N
authors.lastname: Tsuboi
authors.forename: Yasuhiko
authors.initials: Y
authors.lastname: Ito
authors.forename: Seiichi
authors.initials: S
authors.lastname: Matsuo
authors.forename: Takaaki
authors.initials: T
authors.lastname: Kobayashi
authors.forename: Shoichi
authors.initials: S
authors.lastname: Maruyama
mesh_terms: D000273:Adipose Tissue / Q000166:cytology*; D000818:Animals; D000910:Antibodies, Heterophile / Q000276:immunology*; D001402:B-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000502:physiology; D001854:Bone Marrow Cells / Q000166:cytology / Q000276:immunology*; D018929:Cell Culture Techniques; D049109:Cell Proliferation; D002478:Cells, Cultured; D016895:Culture Media, Serum-Free / Q000378:metabolism*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000166:cytology / Q000276:immunology; D051381:Rats; D011916:Rats, Inbred F344; D013154:Spleen / Q000166:cytology; D017154:Stromal Cells / Q000166:cytology / Q000276:immunology*; D013552:Swine; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology / Q000502:physiology
chemical_list: D000910:Antibodies, Heterophile; D016895:Culture Media, Serum-Free