P047 Effect of infliximab and vedolizumab on M1 and M2 macrophages derived from THP-1 cells.

Notararigo, S.(1);Viñuela-Roldán, J.(1);Zurita-Gonzalez, M.J.(1);Dominguez Medina, E.(2);Dominguez-Munos, J.E.(1);Barreiro-de Acosta, M.(1);

(1)Fundacion IDIS, Digestive, Santiago de Compostela, Spain;(2)Fundacion IDIS, BioPharma, Santiago de Compostela, Spain; Fundación IDIS Complejo Hospitalario Santiago de Compostela A Coruña 15706 Spain


Background: Inflammatory bowel diseases encompass two pathologies affecting the digestive tract, Crohn's disease (CD) and ulcerative colitis (UC). They are characterized by a high and chronic inflammatory rate, resulting from activation of the intestinal immune system and increased permeability of the intestinal barrier leading to lesions in the intestinal tract. Non-classical CD14- CD16+ monocytes, are recruited to the focus of inflammation from the peripheral blood and preferentially differentiate to anti-inflammatory macrophages CD206+ CD163+ HLA-DR- in the intestine, playing a key role in the repair of such lesions. In some cases, treatment with biologics, such as vedolizumab, could interfere with this biological process leading to a modification of the innate immune response. Previous results showed that CD and UC had a different distribution of non-classicalmonocytes, leading to the hypothesis that treatment with biologic could modulate macrophage wound healing response.


Methods: Macrophages derived by THP-1 cells were polarized to M0, after PMA treatment, followed by LPS and IFN-γ for M1 macrophages, or IL-4 and IL-13 for M2 macrophages. To assess the effect of biologics on macrophage immune response, Infliximab (IFX) and Vedolizumab (VDZ) were added independently to the cell cultures until polarization process finalized.  Immunophenotyping of M0, M1 and M2, and transcription factor expression profiling of pSTAT-1, pSTAT-6 and pNFκB, were carried out by flow cytometry. Cytokine production of IL-6, TGF-β and IL-10, was performed by ELISA immunoblot. Macrophages immune response was assessed with wound healing assay with Caco-2.


Results: Immunophenotyping revealed that M1 macrophages increased the expression of surface markers like HLA-DR, CD38 and reduced CD11c, vs. M0 macrophages, indeed transcription factor expression of pSTAT-6 and pNFκB were modulated. M2 macrophages showed the decrease of CD163 and HLA-DR vs. M0 macrophages, while no significant effect was observed for CD38 and CD206. Transcription factor expression revealed that pSTAT 6 incremented vs. M0. Cytokine profiling showed a clear difference between the tree macrophages types. Finally wound healing assay with Caco-2 revealed how biologic interfered with innate immune response.


Conclusion: Our results demonstrated that the treatment administration could be responsible of macrophage differential immune response, especially upon biologic treatment. These findings could lead to support the establishment of precision medicine in order to modulate a suitable macrophage response.