CCL2 and hydrops fetalis: Studies have shown an elevated expression of inflammatory cytokines in HF patients, including TNFα, IL-1, IL-6, IL-18, and various chemokines such as monocyte chemoattractant protein-1 (MCP-1/CCL2), IL-8/CXCL-8, CXCL-16, and CCL-21 [154,155].