STAT3 and hydrops fetalis: One study (Tang et al., 2021) designed fibroblast-like MSC-derived exosomes to carry siRNA or antisense oligonucleotides (ASOs) targeting STAT3, demonstrating that iExosiRNA-STAT3 or iExo-mASO-STAT3 downregulated STAT3, reduced ECM deposition, and ameliorated HF.