GREM1 and pulmonary fibrosis: This is in keeping with our previous work (O’Reilly et al., 2014) and also recent work in lung fibrosis and most recently bone marrow-derived stromal cells were found to upregulate Gremlin-1 via IL-6 trans signaling and this could be retarded with the use of an IL-6 monoclonal antibody (Clark et al., 2020).