However, their distribution within the aged LN was grossly disorganized in aged mice, in a similar manner to that seen in the spleen.26 Stromal cells are important for the homeostasis and migration of T cells.4, 27 The structural disorganization seen with age may account for the decrease in T cells seen here, the impaired movement of naive T cells and B cells into the LN previously published,9, 10, 11 along with the decreased recruitment of leucocytes after infection.12 Furthermore, the population of DN (i.e. podoplanin– CD31−) stromal cells was decreased in aged LN. This evidence concerns the gene PECAM1 and infection.