IGHG3 and familial dilated cardiomyopathy: The correlation analysis did not reveal significant correlations between B1 cells or Tr cells and plasma levels of IgM (R = -0.124, P = 0.54, for B1 cells; R = 0.226, P = 0.26, for Tr cells), IgG (R = -0.106, P = 0.60; and R = -0.121, P = 0.55, respectively) and IgG3 (R = 0.011, P = 0.96; and R = -0.332, P = 0.07, respectively) in patients with DCM (Fig. 4B–G).