Mean perivascular cell cluster number and cumulative cluster size identified in male and female mice of the various mouse strains at the age of 20 months.

*Cluster #: number of perivascular cell clusters present per renal cross-section.
**“0”: relative cluster size <0.15; “1”: relative cluster size >0.15.
§strains included in the kinetics analyses: 6, 12 and 20 months.
†strains without TLOs included in lymphatics and liver infiltration analyses.
‡strains with TLOs included in lymphatics and liver infiltration analyses.
n: number of kidneys/mice analyzed; nd: not determined.