OBJECTIVES: To evaluate the anti-inflammatory effect of CTLA4-Ig (abatacept) and dexamethasone (DEX) monotreatment versus their combination and adding methotrexate (MTX) on cultured human macrophages. METHODS: THP-1 cells, activated into macrophages (PMA 0.05 μg/ml), were cultured for 3 and 24 hrs with CTLA4-Ig (500 μg/ml), DEX (10-8 M), MTX (0.05 μg/ml), and CTLA4-Ig combined with DEX or CTLA4-Ig combined with DEX plus MTX. CTLA4-Ig/CD86 interaction was evaluated by FACS analysis. Quantitative real time-PCR (qRT-PCR), immunocytochemistry (ICC) and immunoassay (ELISA) analysis for inflammatory cytokine (IL-1β, TNF-α, IL-6) expression were performed. RESULTS: FACS analysis showed in macrophages treated with CTLA4-Ig alone, CTLA4-Ig-DEX and CTLA4-Ig-DEX-MTX a CD86 decrease of almost 35%, versus untreated cells (CNT). After 3 hrs, macrophages treated with DEX alone or with CTLA4-Ig-DEX or CTLA4-Ig-DEX-MTX showed a significant reduction (p<0.05) for all cytokines gene expression, that was still significant for IL-1β after 24 hrs (p<0.05). After 3 hrs, CTLA4-Ig alone significantly (p<0.05) reduced all cytokine genes; however, after 24 hrs still evident only for TNF-α (p<0.05). After 24 hrs CTLA4-Ig-DEX induced a significant decrease of gene expression (p<0.05) for TNF-α and IL-6, whereas CTLA4-Ig-DEX-MTX induced a decrease (p<0.05) limited to IL-6, versus CNT. Finally, ICC showed, after 24 hrs of CTLA4-Ig-DEX or CTLA4-Ig-DEX-MTX treatment a reduction (p<0.05) of IL-1β and IL-6 expression, versus CNT; DEX alone reduced only IL-1β (p<0.05). ELISA analysis confirmed these results. CONCLUSIONS: CTLA4-Ig-DEX and CTLA4-Ig-DEX-MTX combined treatments, decreased at any level the inflammatory cytokine expression more efficiently then monotreatments on activated cultured human macrophages.
OBJECTIVES: To evaluate the anti-inflammatory effect of CTLA4-Ig (abatacept) and dexamethasone (DEX) monotreatment versus their combination and adding methotrexate (MTX) on cultured human macrophages. METHODS: THP-1 cells, activated into macrophages (PMA 0.05 μg/ml), were cultured for 3 and 24 hrs with CTLA4-Ig (500 μg/ml), DEX (10-8 M), MTX (0.05 μg/ml), and CTLA4-Ig combined with DEX or CTLA4-Ig combined with DEX plus MTX. CTLA4-Ig/CD86 interaction was evaluated by FACS analysis. Quantitative real time-PCR (qRT-PCR), immunocytochemistry (ICC) and immunoassay (ELISA) analysis for inflammatory cytokine (IL-1β, TNF-α, IL-6) expression were performed. RESULTS: FACS analysis showed in macrophages treated with CTLA4-Ig alone, CTLA4-Ig-DEX and CTLA4-Ig-DEX-MTX a CD86 decrease of almost 35%, versus untreated cells (CNT). After 3 hrs, macrophages treated with DEX alone or with CTLA4-Ig-DEX or CTLA4-Ig-DEX-MTX showed a significant reduction (p<0.05) for all cytokines gene expression, that was still significant for IL-1β after 24 hrs (p<0.05). After 3 hrs, CTLA4-Ig alone significantly (p<0.05) reduced all cytokine genes; however, after 24 hrs still evident only for TNF-α (p<0.05). After 24 hrs CTLA4-Ig-DEX induced a significant decrease of gene expression (p<0.05) for TNF-α and IL-6, whereas CTLA4-Ig-DEX-MTX induced a decrease (p<0.05) limited to IL-6, versus CNT. Finally, ICC showed, after 24 hrs of CTLA4-Ig-DEX or CTLA4-Ig-DEX-MTX treatment a reduction (p<0.05) of IL-1β and IL-6 expression, versus CNT; DEX alone reduced only IL-1β (p<0.05). ELISA analysis confirmed these results. CONCLUSIONS:CTLA4-Ig-DEX and CTLA4-Ig-DEX-MTX combined treatments, decreased at any level the inflammatory cytokine expression more efficiently then monotreatments on activated cultured human macrophages.