title: Action of methotrexate and tofacitinib on directly stimulated and bystander-activated lymphocytes.
abstract: Chronic inflammation associated with autoimmune activation is characteristic of rheumatic diseases from childhood to adulthood. In recent decades, significant improvements in the treatment of these types of disease have been achieved using disease modifying anti-rheumatic drugs (DMARDs), such as methotrexate (MTX) and, more recently, using biologic inhibitors. The recent introduction of kinase inhibitors (for example, tofacitinib; Tofa) further increases the available ARDs. However, there are patients that do not respond to any treatment strategies, for whom combination therapies are proposed. The data regarding the combined action of different drugs is lacking and the knowledge of the mechanisms of ARDs and their actions upon pathogenic lymphocytes, which are hypothesized to sustain disease, is poor. An in vitro model of inflammation was developed in the current study, in which stimulated and unstimulated lymphocytes were cultured together, but tracked separately, to investigate the action of MTX and Tofa on the two populations. By analysing lymphocyte proliferation and activation, and cytokine secretion in the culture supernatants, it was established that, due to the presence of activated cells, unstimulated cells underwent a bystander activation that was modulated by the ARDs. Additionally, varying administration schedules were demonstrated to affect lymphocytes differently in vitro, either directly or via bystander activation. Furthermore, MTX and Tofa exerted different effects; while MTX showed an antiproliferative effect, Tofa marginally effected activation, although only a slight antiproliferative action, which could be potentiated by sequential treatment with MTX. Thus, it was hypothesized that these differences may be exploited in sequential therapeutic strategies, to maximize the anti‑rheumatic effect. These findings are notable and must be accounted for, as bystander‑activated cells in vivo could contribute to the spread of autoimmune activation and disease progression.
authors.affiliation: Department of Advanced Diagnostic and Clinical Trials, Institute for Maternal and Child Health, IRCCS 'Burlo Garofolo', I-34137 Trieste, Italy.
authors.forename: Elisa
authors.initials: E
authors.lastname: Piscianz
authors.affiliation: Department of Medical, Surgical and Health Sciences, University of Trieste, I-34100 Trieste, Italy.
authors.forename: Vanessa
authors.initials: V
authors.lastname: Candilera
authors.affiliation: Department of Advanced Diagnostic and Clinical Trials, Institute for Maternal and Child Health, IRCCS 'Burlo Garofolo', I-34137 Trieste, Italy.
authors.forename: Erica
authors.initials: E
authors.lastname: Valencic
authors.affiliation: Department of Medical, Surgical and Health Sciences, University of Trieste, I-34100 Trieste, Italy.
authors.forename: Claudia
authors.initials: C
authors.lastname: Loganes
authors.affiliation: Department of Medical, Surgical and Health Sciences, University of Trieste, I-34100 Trieste, Italy.
authors.forename: Greta
authors.initials: G
authors.lastname: Paron
authors.affiliation: Department of Advanced Diagnostic and Clinical Trials, Institute for Maternal and Child Health, IRCCS 'Burlo Garofolo', I-34137 Trieste, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: De Iudicibus
authors.affiliation: Department of Life Sciences, University of Trieste, I-34100 Trieste, Italy.
authors.forename: Giuliana
authors.initials: G
authors.lastname: Decorti
authors.affiliation: Department of Paediatrics, Institute for Maternal and Child Health, IRCCS 'Burlo Garofolo', I-34137 Trieste, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Tommasini
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology*; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects* / Q000276:immunology*; D008214:Lymphocytes / Q000187:drug effects* / Q000276:immunology* / Q000378:metabolism; D008727:Methotrexate / Q000494:pharmacology*; D010880:Piperidines / Q000494:pharmacology*; D047428:Protein Kinase Inhibitors / Q000494:pharmacology*; D011743:Pyrimidines / Q000494:pharmacology*; D011758:Pyrroles / Q000494:pharmacology*
chemical_list: D000964:Antimetabolites, Antineoplastic; D016207:Cytokines; D010880:Piperidines; D047428:Protein Kinase Inhibitors; D011743:Pyrimidines; D011758:Pyrroles; C479163:tofacitinib; D008727:Methotrexate