Efficient kidney gene transfer and proximal tubule transduction using self-complementary AAV.cc47 vectors

Gene delivery to critical cell types within the kidney can enable preclinical evaluation of gene therapies for kidney disease. The novel adeno-associated virus AAV.cc47 was discovered after sequential evolution in mice, pigs, and macaques and improved transduction in multiple tissues but without in-depth exploration of the kidney. We observed robust kidney transduction by AAV.cc47 vectors in mice in vivo and in human kidney organoids compared to AAV9, mostly within the proximal tubule (PT) epithelium. We then developed a quantitative analysis method of transgene expression utilizing automated classification of nephron cell types coupled with cellular expression. Despite exhibiting similar biodistribution to AAV9 in renal and extrarenal tissues, AAV.cc47 consistently transduced the kidney at higher efficiency, with >80% of PT epithelium transduced at low, systemically administered vector dose. Self-complementary AAV.cc47 vectors appear to transduce a subset of PT epithelium, with undetectable transduction of non-PT cells. This method could be adapted to evaluate different AAV vectors transducing other kidney cell types. We also demonstrate the utility of dual AAV.cc47 vectors to increase genome payload capacity for kidney gene transfer. AAV.cc47 represents a promising vector for use as a research tool and possibly clinical application for kidney disease.