Comparative analysis of drug action on B-cell proliferation and differentiation for mycophenolic acid, everolimus, and prednisolone.
BACKGROUND
Although more attention has been paid recently to B-cell immunity, assay for B-cell analysis has yet to be clinically applicable because, unlike T cell, a B-cell culture system has not been well established.


METHODS
We attempted to develop an in vitro culture system for the proliferation and differentiation of peripheral B cells into plasma cells, and to analyze the action of everolimus (EVR), mycophenolic acid (MPA), and prednisolone (PRD).


RESULTS
Using a three-step culture system, peripheral CD19 B cells could differentiate into plasma cells and produce IgG antibody. Activated B cells (CD19(hi)CD38(lo)IgD(-)), plasmablasts (CD19(hi)CD38(hi)IgD(-)), and plasma cells (CD19(lo/-)CD38(hi)IgD(-)) were observed as a main cell subset in step 1 (day 0-4), 2 (day 4-7), and 3 (day 7-10), respectively. IgG production on day 10 was significantly suppressed by EVR, MPA, and PRD, but not cyclosporine. Although both EVR and MPA inhibited B-cell proliferation and differentiation in step 1, EVR suppressed B-cell differentiation in step 2. Only a high concentration of PRD significantly inhibited B-cell proliferation, differentiation, and IgG production in step 3.


CONCLUSIONS
Although both MPA and EVR efficiently suppressed cell proliferation during the early phase of B-cell immune reaction, EVR could act in a later phase than MPA. PRD at a high concentration worked even in the last phase. An in vitro B-cell culture system would clarify the mode of drug action during B-cell differentiation and provide useful information on the effective selection or combination of immunosuppressive agents.
1 Department of Transplant Immunology, Nagoya University School of Medicine, Nagoya, Japan. 2 Japanese Red Cross Aichi Blood Center, Seto, Japan. 3 Department of Surgery II, Nagoya University School of Medicine, Nagoya, Japan. 4 Address correspondence to: Takaaki Kobayashi, M.D., Department of Transplant Immunology, Nagoya University School of Medicine, 65, Tsurumai-cho, Showa-ku, Nagoya 466-8550, Japan.
Masataka
M
Haneda
Mami
M
Owaki
Takafumi
T
Kuzuya
Kenta
K
Iwasaki
Yuko
Y
Miwa
Takaaki
T
Kobayashi
D018941:Antigens, CD19 / Q000378:metabolism; D001402:B-Lymphocytes / Q000166:cytology* / Q000187:drug effects; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects*; D016572:Cyclosporine / Q000737:chemistry; D004353:Drug Evaluation, Preclinical; D004791:Enzyme Inhibitors / Q000494:pharmacology; D004797:Enzyme-Linked Immunosorbent Assay; D000068338:Everolimus; D005434:Flow Cytometry; D005938:Glucocorticoids / Q000494:pharmacology; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D007166:Immunosuppressive Agents / Q000494:pharmacology; D007963:Leukocytes, Mononuclear / Q000166:cytology; D008213:Lymphocyte Activation / Q000187:drug effects; D009173:Mycophenolic Acid / Q000494:pharmacology*; D010950:Plasma Cells / Q000378:metabolism; D011239:Prednisolone / Q000494:pharmacology*; D020123:Sirolimus / Q000031:analogs & derivatives* / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology
D018941:Antigens, CD19; D004791:Enzyme Inhibitors; D005938:Glucocorticoids; D007074:Immunoglobulin G; D007166:Immunosuppressive Agents; D016572:Cyclosporine; D000068338:Everolimus; D011239:Prednisolone; D009173:Mycophenolic Acid; D020123:Sirolimus