AHR and rheumatoid arthritis: In addition, the Aryl hydrocarbon receptor, known as Th17 cell differentiation promoter (Nakahama et al., 2011; Talbot et al., 2018), and TREM1 signalling involved in systemic and local inflammatory process activation (Kuai et al., 2009; Peng et al., 2019; Inanc et al., 2021), were also processes identified to be associated with the DMARDs-naïve RA PBMC.