FOSL2 and systemic sclerosis: However, these findings are tempered by recent reports showing that IL-1 receptor inhibition can exacerbate pulmonary fibrosis; employing a murine model of SSc through the overexpression of Fra-2 (fos-related antigen-2), mice treated with an IL-1 inhibitor demonstrated worse lung function, enhanced Th2 inflammation, and greater numbers of pro-fibrotic, alternatively activated macrophages (Birnhuber et al., 2019).