title: Bortezomib induces selective depletion of alloreactive T lymphocytes and decreases the production of Th1 cytokines.
abstract: We explored the ability of the proteasome inhibitor bortezomib, which prevents nuclear factor kappaB (NF-kappaB) activation, to block T-cell activation, proliferation, and survival within alloreactive compared with resting T cells. For this purpose, T cells were stimulated with PHA, alphaCD3/alphaCD28, or allogeneic dendritic cells or through mixed lymphocyte cultures. NF-kappaB expression increased in activated T lymphocytes compared with resting T cells. Of interest, the higher the NF-kappaB expression, the more intense the proliferative blockade induced by bortezomib. Moreover, after mixed lymphocyte reaction (MLR) cultures, alloreactive T cells were 2 logs more sensitive to bortezomib-induced apoptosis than the resting T-cell counterpart. This effect was due to a selective induction of apoptosis among activated T cells that was related to caspase activation and cleavage of the antiapoptotic bcl-2 protein and was partially abolished by the addition of the pancaspase inhibitor Z-VAD-FMK. In addition, after secondary MLR, the number of activated T cells was significantly reduced among T lymphocytes previously cultured with bortezomib when cells from the same donor were used as stimulating cells. By contrast, when third-party donor cells were used as stimulating cells, no significant differences were observed between T lymphocytes previously exposed or not to the drug, indicating a highly specific depletion of T lymphocytes alloreactive against primary donor antigens. The addition of bortezomib decreased not only the proliferation and viability of activated T lymphocytes but also the levels of IFNgamma and IL-2, which were significantly decreased among activated T cells cultured with bortezomib at doses ranging from 10 to 100 nM. In conclusion, at concentrations reached in the clinical setting, bortezomib induces selective apoptosis and decreases Th1 response among alloreactive T lymphocytes while it barely affects unstimulated T cells. These results establish the basis for the clinical use of bortezomib in the management of graft-versus-host disease (GVHD).
authors.affiliation: Servicio de Hematología y CIC Salamanca, Paseo de San Vicente, 58-182, 37007, Salamanca, Spain.
authors.forename: Belén
authors.initials: B
authors.lastname: Blanco
authors.forename: José A
authors.initials: JA
authors.lastname: Pérez-Simón
authors.forename: Luis I
authors.initials: LI
authors.lastname: Sánchez-Abarca
authors.forename: Xonia
authors.initials: X
authors.lastname: Carvajal-Vergara
authors.forename: Juan
authors.initials: J
authors.lastname: Mateos
authors.forename: Belén
authors.initials: B
authors.lastname: Vidriales
authors.forename: Natalia
authors.initials: N
authors.lastname: López-Holgado
authors.forename: Patricia
authors.initials: P
authors.lastname: Maiso
authors.forename: Mercedes
authors.initials: M
authors.lastname: Alberca
authors.forename: Eva
authors.initials: E
authors.lastname: Villarón
authors.forename: David
authors.initials: D
authors.lastname: Schenkein
authors.forename: Atanasio
authors.initials: A
authors.lastname: Pandiella
authors.forename: Jesús
authors.initials: J
authors.lastname: San Miguel
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D001897:Boronic Acids / Q000494:pharmacology*; D000069286:Bortezomib; D049109:Cell Proliferation / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000096:biosynthesis*; D006086:Graft vs Host Disease / Q000188:drug therapy; D006801:Humans; D066298:In Vitro Techniques; D007519:Isoantigens; D008213:Lymphocyte Activation / Q000187:drug effects; D007959:Lymphocyte Culture Test, Mixed; D011480:Protease Inhibitors / Q000494:pharmacology*; D011719:Pyrazines / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects* / Q000276:immunology*; D018417:Th1 Cells / Q000166:cytology / Q000187:drug effects / Q000276:immunology
chemical_list: D001897:Boronic Acids; D016207:Cytokines; D007519:Isoantigens; D011480:Protease Inhibitors; D011719:Pyrazines; D000069286:Bortezomib