CXCR4 and systemic sclerosis: Diffuse cutaneous sclerosis, the presence of anti-topoisomerase I antibodies, anti-CXCR3 and anti-CXCR4 antibodies, older age, Afro-American ethnicity, low FVC or DLCO and the extent of ILD in HRCT results were all associated with the progression of SSc-ILD [40,41].