INDOMETHACIN TREATMENT MODIFY THE EXPRESSION OF CCR1, CXCR4, AXL, AND RANK AT DIFFERENT STAGES OFIN-VITRO DIFFERENTIATION OF DENDRITIC CELLS

MARÍA CATALINA LAVA; DENISE MARIEL RISNIK; CINTHIA MARIEL OLEXEN; DIEGO ALFREDO ROSSO; EUGENIO ANTONIO CARRERA SILVA; ANDREA EMILSE ERRASTI

Atenas

Congreso; 39th Annual Meeting of the Histiocyte Society; 2023

Histiocyte Society

Purpose: Indomethacin, a non-selective COX inhibitor (NSAID) is effective in the treatment of bone LCH. Nevertheless, the specific mechanism of action involved in the therapeutic benefit is not defined. We hypothesized that Indomethacin restrains the homing and migration of Langerhans cells and/or their precursors to the bone. To test this hypothesis, we analyze the expression of homing receptors CCR1, CXCR4, AXL, and Rank in monocytes and dendritic cells (DC) under indomethacin treatment. To determine if this effect is extended to another NSAID, we compare it with ibuprofen. Methods: CD14+ monocytes from Peripheral Blood Mononuclear cells of healthy volunteers were used as precursor cells, and conventional DC (GM-CSF+IL-4) and inflammatory Langerhans-like cells “LC-like” (IL-4+GM-CSF+TNFα+TGFβ+dexamethasone were in-vitro differentiated from the monocytes. The treatment was performed with 100uMofIndomethacinorIbuprofenorvehicle.qPCR and flow cytometry assays were performed to evaluate their effect on gene expression and proteins, respectively.Results: Indomethacin significantly reduced RNA expression of RANK (N=6, P=0.0156), AXL (N=6, P=0.031), and CCR1 (N=8, P=0.007) in conventional DC. AXL was reduced in both conventional DC and “LC-like” cells confirmed by qPCR and flow cytometry. Treatment of monocytes with Indomethacin reduced the expression of AXL (N=9, P=0.004) and CXCR4 (N=6, P=0.031), measured by flow cytometry. On the contrary, RNA expression of RANK was upregulated (N=9, P=0.0039) when monocytes were treated with Indomethacin. On the other hand, when conventional DCs were treated with Ibuprofen it also showed a reduction in the RNA expression of CCR1 (N=4, P=0.062) and RANK (N=4, P=0.062). Monocyte treatment with ibuprofen does not modify AXL expression but significantly reduces CXCR4 levels measured by flow cytometry (N=6, P=0.031). Conclusions: Indomethacin affects cell migration molecules on DC and their precursors, with some specific differences when compared with ibuprofen.