To investigate the relationship between decoy receptor 2 (DcR2) and cellular senescence in embryonic kidney development by studying the localization and expression of DcR2 during the development of mouse embryonic kidney.

Kidney tissues of mice at the age of embryonic 12.5d, 16.5d, 20.5d, and postnatal 8w were selected respectively. Periodic acid Schiff (PAS) staining was used to observe the morphology of kidney tissues. Quantitative RT-PCR was used to detect the expression level of DcR2 mRNA. Immunohistochemical staining was used to observe the expression distribution of DcR2. And immunofluorescence co-staining was used to detect the co-expression relationship between DcR2 and proximal renal tubule marker villin, distal renal tubule marker aquaporin 2 (AQP-2), aging marker P16, nuclear morphological marker LaminB1, proliferation marker Ki-67, and proliferating cell nuclear antigen (PCNA).

With the development of the embryonic kidneys, the expression of DcR2 mRNA and protein in embryonic kidney tissues increased gradually, and were significantly higher than those in adult kidneys. DcR2 was specifically expressed in renal tubules, and co-expressed with villin, but not with AQP-2. DcR2-positive cells expressed high expression of P16, but low expression of LaminB1, Ki-67, and PCNA.

DcR2 was specifically expressed in embryonic kidney proximal tubular cells, and its expression level increased with embryonic age. In addition, DcR2-positive cells had cellular senescence-related phenotypes, suggesting that DcR2 may play an important role in regulating cellular senescence during embryonic kidney development.