BACKGROUND: Dipeptidyl peptidase-IV (DPP-IV) enzymatic activity controls biological halftime of multiple local mediators. Its deregulation is associated with pathogenesis of several autoimmune diseases, including rheumatoid arthritis (RA). Although DPP-IV is the canonical representative of the group, a number of other proteins have been shown to have similar enzymatic activity. This study was aimed to identify the molecular source of DPP-IV activity in synovial fluid (SF) and fluid mononuclear cells (FMNC) in patients with RA and osteoarthritis (OA). In addition, the association of DPP-IV and the concentration of stromal cell-derived factor-1alpha (SDF), DPP-IV substrate, were evaluated. METHODS: DPP-IV activity was measured by the kinetic fluorimetric method. The expression of studied molecules in FMNC and their concentrations in SF were assayed using flow cytometry and ELISA respectively. RESULTS: DPP-IV activity in SF, dominantly derived from the canonical DPP-IV, does not significantly differ between RA and OA. However, a significantly lower DPP-IV activity and expression in FMNC was found in RA as opposed to OA patients. Negative correlation between SDF concentration in SF and the relative amount of CD3+CD26+ cells was observed. CONCLUSIONS: We report decreased presence of DPP-IV/CD26 in CD3+ FMNC in RA, which also may participate on impaired balance of SDF concentration in SF. Copyright 2010 Elsevier B.V. All rights reserved.
BACKGROUND:Dipeptidyl peptidase-IV (DPP-IV) enzymatic activity controls biological halftime of multiple local mediators. Its deregulation is associated with pathogenesis of several autoimmune diseases, including rheumatoid arthritis (RA). Although DPP-IV is the canonical representative of the group, a number of other proteins have been shown to have similar enzymatic activity. This study was aimed to identify the molecular source of DPP-IV activity in synovial fluid (SF) and fluid mononuclear cells (FMNC) in patients with RA and osteoarthritis (OA). In addition, the association of DPP-IV and the concentration of stromal cell-derived factor-1alpha (SDF), DPP-IV substrate, were evaluated. METHODS:DPP-IV activity was measured by the kinetic fluorimetric method. The expression of studied molecules in FMNC and their concentrations in SF were assayed using flow cytometry and ELISA respectively. RESULTS:DPP-IV activity in SF, dominantly derived from the canonical DPP-IV, does not significantly differ between RA and OA. However, a significantly lower DPP-IV activity and expression in FMNC was found in RA as opposed to OA patients. Negative correlation between SDF concentration in SF and the relative amount of CD3+CD26+ cells was observed. CONCLUSIONS: We report decreased presence of DPP-IV/CD26 in CD3+ FMNC in RA, which also may participate on impaired balance of SDF concentration in SF. Copyright 2010 Elsevier B.V. All rights reserved.
Authors: Oscar J Cordero; Rubén Varela-Calviño; Tania López-González; Cristina Calviño-Sampedro; Juan E Viñuela; Coral Mouriño; Íñigo Hernández-Rodríguez; Marina Rodríguez-López; Bruno Aspe de la Iglesia; José María Pego-Reigosa; José María Pego Journal: PLoS One Date: 2015-07-15 Impact factor: 3.240