Consistently, macrophages and monocyte have been detected in the synovial fluid of OA joints, which positively correlate with joint stiffness, pain, and reduced quality of life.[44] Harini et al demonstrated that monocyte recruitment via CCL2/CCR2 signal propagated inflammation and tissue damage in OA.[45] Therefore, our study estimated that the 4 common DEGs were associated with the occurrence and progress of OA and HF via regulating several immune cells. The gene discussed is CCL2; the disease is hydrops fetalis.