title: Effect of mycophenolic acid and bortezomib on purified human B cells: an in vitro study of long-term functionally stable MICA-sensitized renal recipients.
abstract: OBJECTIVE
  We sought to develop a B-cell in vitro culture system and test B cells isolated from sensitized kidney recipients and healthy controls, and assess the effectiveness of proteasome inhibitors and mycophenolic acid on antibody secretion and cell apoptosis.
  
  
  METHODS
  CD19(+) B cells and CD19(+)CD27(+) memory B-cell subsets were detected from peripheral blood mononuclear cells obtained from 6 MICA-sensitized kidney recipients and 6 healthy controls. Peripheral blood B cells were isolated and cultured with CpG2006, PMA, MICA antigen, B-cell activating factor, CD40 ligand (CD40L), human recombinant IL-2 (rhuIL-2), rhuIL-10, rhuIL-4, and rhuIL-21. After culturing for 7 days, we tested several variables of B-cell activity including differentiation, apoptosis, and IgM production. We also assessed the effects of 2 immunosuppressive drugs (mycophenolic acid and bortezomib) on antibody secretion and cellular apoptosis.
  
  
  RESULTS
  Kidney recipients had a lower ratio of CD19+ B cells in peripheral blood mononuclear cells than did healthy controls. However, the percentage of CD19(+)CD27(+) B cells was higher in kidney recipients than in healthy controls. In the cell stimulation culture system, the ratio of CD19(+) B cells, CD19(+)CD27(+) B cells, and CD19(+)CD138(+) B cells increased after culturing for 7 days compared with unstimulated controls. In addition, the percentage of apoptotic B cells decreased, and antibody production increased in sensitized transplant patients and healthy controls. Treatment with bortezomib or mycophenolic acid induced B-cell apoptosis and inhibited secretion of antibodies.
  
  
  CONCLUSIONS
  This study describes establishment of a B-cell in vitro culture system, showing that B cells may be stimulated to secrete antibodies. The study also provides an assay for studying B cells in vitro. This study provides information suggesting that bortezomib and mycophenolic acid can inhibit B-cell antibody secretion.
authors.affiliation: Department of Urology, First People's Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, PR China.
authors.forename: Zuo wei
authors.initials: Zw
authors.lastname: Li
authors.forename: Xiao fei
authors.initials: Xf
authors.lastname: Wen
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.forename: Ming
authors.initials: M
authors.lastname: Luo
authors.forename: Jian xin
authors.initials: Jx
authors.lastname: Qiu
mesh_terms: D000368:Aged; D018941:Antigens, CD19 / Q000378:metabolism; D017209:Apoptosis / Q000187:drug effects; D001402:B-Lymphocytes / Q000187:drug effects* / Q000276:immunology / Q000473:pathology; D001897:Boronic Acids / Q000494:pharmacology*; D000069286:Bortezomib; D016022:Case-Control Studies; D002454:Cell Differentiation / Q000187:drug effects; D002478:Cells, Cultured; D005260:Female; D015395:Histocompatibility Antigens Class I / Q000097:blood / Q000276:immunology*; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D066298:In Vitro Techniques; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D009173:Mycophenolic Acid / Q000494:pharmacology*; D061988:Proteasome Inhibitors / Q000494:pharmacology; D011719:Pyrazines / Q000494:pharmacology*
chemical_list: D018941:Antigens, CD19; D001897:Boronic Acids; D015395:Histocompatibility Antigens Class I; D007075:Immunoglobulin M; C099187:MHC class I-related chain A; D061988:Proteasome Inhibitors; D011719:Pyrazines; D000069286:Bortezomib; D009173:Mycophenolic Acid