For example, the shared targets monocyte chemoattractant protein 1 (CCL; MCP-2) and unique target CTGF both mediate pro-fibrotic effects in SSc, CCL2 increases the production of collagen in dermal fibroblasts by inducing the differentiation of interleukin-4 (IL-4)-producing T cells81, and CTGF favor ECM accumulation to promote tissue fibrosis82. Here, IL4 is linked to systemic sclerosis.