A Nature Communications study using multi‑lineage hepatic organoids revealed a mechanism of drug‑induced liver injury driven by toxic exosomes released from damaged cells — an indirect hepatotoxic pathway that conventional assays may miss. The organoids recapitulated cross‑cell signaling that propagated injury and identified exosome cargo linked to downstream hepatocyte dysfunction. In parallel, researchers at the Terasaki Institute developed a vascularized liver tissueoid‑on‑a‑chip (LToC) that recreates structural and functional cues of the human liver, enabling studies of regeneration and transplant rejection in a controlled microphysiological system. The LToC platform provides perfusable vasculature, multicellular architecture and readouts amenable to drug testing and immune‑interaction studies. Both advances enhance preclinical tools for DILI risk assessment, transplant biology, and regenerative medicine, offering routes to detect safety liabilities earlier and model complex tissue responses.