title: Positive effect on T-cell regulatory apoptosis by mycophenolate mofetil.
abstract: The regulatory benefit of apoptosis (activation-induced cell death, AICD) in T cells may be impacted by immunosuppressive agents. We examined this for mycophenolate mofetil (MMF) compared with cyclosporine (CYA). Peripheral blood leukocytes (PBL) were stimulated by either Staph enterotoxin B (SEB) or by anti-CD3 plus anti-CD28. Cell division analysis (sequential reduction in carboxyflourescein diacetate succinimidyl ester, CFSE) was used to measure proliferation and determine status of different cell generations. Apoptosis was measured by annexin V staining, and FasL expression by anti-FasL antibody staining, of activated cells using flow cytometry. CSA and mycophenolic acid (MPA, the active agent of MMF) were added in titration in 3-day cultures. We found that CSA caused diminution in apoptosis but MPA increased it with SEB stimulation. The CSA effect on apoptosis was present when a more calcineurin-dependent stimulus. anti-CD3+ anti-CD28, was used but the MPA effect was less, producing a decrease only in the undivided cells. To look more directly at the differential effect on calcineurin-dependent AICD gene induction of the two agents, we measured Fas-L expression with anti-CD-3 + CD28 stimulation, and confirmed that CYA caused a major decrement in appearance of Fas-L, whereas MPA caused a converse accumulation of it. This seems to be explained by the block more distal in cell activation, resulting in a build-up of a precursor in the activation pathways. We conclude that MMF treatment may be rationale as an adjunct to calcineurin inhibitor treatment because of its converse effect on T cell regulatory apoptosis.
authors.affiliation: The Johns Hopkins Medical Institutions, and the Laboratory of Immunology, National Institute on Aging, National Institutes of Health, Baltimore, MD 21287-8611, USA.
authors.forename: M
authors.initials: M
authors.lastname: Nakamura
authors.forename: N
authors.initials: N
authors.lastname: Ogawa
authors.forename: A
authors.initials: A
authors.lastname: Shalabi
authors.forename: W R
authors.initials: WR
authors.lastname: Maley
authors.forename: D
authors.initials: D
authors.lastname: Longo
authors.forename: J F
authors.initials: JF
authors.lastname: Burdick
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D016572:Cyclosporine / Q000494:pharmacology*; D005434:Flow Cytometry; D006801:Humans; D007166:Immunosuppressive Agents / Q000494:pharmacology*; D009173:Mycophenolic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000187:drug effects*
chemical_list: D007166:Immunosuppressive Agents; D016572:Cyclosporine; D009173:Mycophenolic Acid