CD4 and rheumatoid arthritis: Our study revealed that pathways related to antigen presentation via MHC class II in CD16-monocytes, especially HLA-DRA and CD4 interaction, and pathways response to IFNγ might be associated with higher anti-SARS-CoV2-IgG level in RA patients, while pathways related to chemotaxis were kept in those with low anti-SARS-CoV2-IgG antibody.