01835nas a2200337   4500000000100000008004100001260001500042100002100057700002300078700001800101700001700119700001900136700002000155700001800175700001900193700002100212700002100233700001700254700001400271700001800285700002100303700001700324700001700341700002000358700002300378245007800401856005600479300001300535490000800548520094100556       2026                            d  c2026-07-021 aConnor C. Fausto1 aFokion Glykofrydis1 aNavneet Kumar1 aJack Schnell1 aReka L. Csipan1 aFaith De Kuyper1 aMinnal Kunnan1 aBrendan Grubbs1 aMatthew Thornton1 aMichael Thompson1 aEnmian Chang1 aXuduo Wen1 aManuel Pelayo1 aMaryAnne Achieng1 aAnoothi Seth1 aKelly Street1 aLeonardo Morsut1 aNils O. Lindström00aPatterning human kidney organoids with synthetic Wnt-secreting organizers  uhttps://www.science.org/doi/10.1126/science.adu9122  aeadu91220 v3933 aHuman stem cell–derived miniature organs, including kidney organoids, reproduce aspects of tissue development but lack reliable spatial patterning. In embryos, spatial organization is often established by developmental organizers that generate morphogenetic fields. However, how such organizing geometry operates in kidney nephrogenesis—and whether it can be reconstructed in vitro—has remained unclear. Using spatial transcriptomics of human kidney development, we found that nascent nephrons establish a collecting duct adjacent-to-distant polarity bordering a WNT11-WNT9B signaling boundary. Engineered WNT-secreting cellular organizers introduced into kidney organoids restored this organizing geometry, biasing distal nephron differentiation and orienting nephron morphogenesis toward the signal source, which demonstrates that developmental signaling geometry can be reconstructed synthetically to control tissue patterning.