Similarly, our results showed the elevated COL3A1 expression was positively correlated with CD8(+) T cells, M2 macrophages, and T follicular helper cells, while also negatively correlated with eosinophils, resting CD4(+) memory T cells, and memory B cells, which suggested COL3A1 may sever as a key immune-related gene playing a central role of immune mechanism in the progression of DCM. Here, CD8A is linked to familial dilated cardiomyopathy.