For example, the abundance of Tfh cells was significantly reduced in both DCM and AF patients, and hub immune-related common genes were predominantly favorably correlated with Tfh cells, CD4+T cells, iTreg cells, and Th2 cells infiltration and primarily negatively correlated with Neutrophil, Th17 cells, and NKT cells infiltration in DCM and AF patients (Figure 7). Here, CD4 is linked to atrial fibrillation.