TGFB1 and hydrops fetalis: Through single-cell RNA-seq, spatial transcriptomics, and genetic perturbation, a recent study found that high-temperature requirement, a serine peptidase 3 (Htra3) is a critical regulator of cardiac fibrosis and HF by maintaining the identity of quiescent cardiac fibroblasts through degrading transforming growth factor-β (TGF-β) (20).