Weekly issue 2026-W41 ·
Large-scale organoid-derived cyst cultures as a drug discovery platform for polycystic kidney disease
Plain language
Organoids are tiny structures grown in the lab from stem cells that copy parts of an organ. Researchers developed a way to grow thousands of kidney organoids that form cysts like those in ADPKD, so that many possible drugs can be tested at once. The cysts responded to some experimental compounds but not to tolvaptan, which the authors linked to the organoids having little of the receptor that tolvaptan acts on. Testing a small set of compounds pointed to TLR4, a protein involved in the immune response, as a possible target. This is a laboratory tool for finding drug candidates; none of these compounds is a treatment for people.
Clinical note
Preclinical platform. Day-12 nephron organoids from wild-type and PKD2-deficient hiPSC lines were dissociated and grown in suspension under ureteric bud (UB) conditions, yielding up to 2000 UB organoids from about 50 nephron organoids within 7 days (AQP2, WNT9B and KRT8 positive). PKD2-deficient UB organoids began cystogenesis within 7 days, with very high cyst-forming efficiency by about 20 days. Cysts expressed ADPKD markers and responded to JQ1 (bromodomain inhibitor) and QNZ (NF-κB inhibitor) but not tolvaptan, consistent with low AVPR2 expression. A small-molecule screen identified M1, a putative TLR4 antagonist, that reduced cyst size; TAK-242 reduced and lipopolysaccharide increased cyst formation, consistent with TLR4-driven cystogenesis. In vitro data only.
Question for your next visit
Are there clinical trials for ADPKD that are testing new kinds of medicines?