Macrophage Accumulation and Cyst Expansion in Pkd2, Ift88, and Double Mutant Mouse Models

Kidney cyst formation occurs due to loss of cilia localized polycystin proteins (e.g., Pkd1 or Pkd2) or ciliary structure (e.g., Ift88 or Kif3a). However, cyst progression is more rapid in polycystin mutant mice compared to cilia mutant mice, and loss of cilia in the polycystin mutant background (e.g., Pkd2 and Kif3a mutation) greatly attenuates cyst development. This led to the proposal that the polycystins function to repress a cyst promoting pathway that is dependent on an intact cilium. Renal macrophages are also involved in regulating cyst progression, and the macrophage accumulation paralles with cyst expansion. but it is unknown whether this occurs through a cilia-dependent pathway or the consequence of cyst expansion. To address this question, we compared macrophage accumulation level and phenotypes in cystic kidneys from Pc2 mutant and Ift88; Pkd2 double mutant mice by prefromed 10x Genomics scRNAseq techniques. And to avoid the varying cyst severity in these mouse from different mutations, the cystic kidneys from Pc2 mutant and Ift88; Pkd2 double mutant mice were collected by adjusting for cystic indices rather than age.