Figure 6.

Egress of fibrocyte-like cells to spleen occurs without injury in aged mice. A: Migration of Luc⁺ cells was compared in young (6 to 8 weeks, n = 10) and aged (older than 20 months, n = 10) Col-Luc→wt mice before and during CCl₄-induced liver injury. Data are given as mean ± SEM p/s/cm2/sr. *P < 0.05, ***P < 0.01. Young and aged mice were compared at each time point. B: Migration of fibrocytes into peripheral organs in Col-GFP→wt mice was demonstrated using fluorescent microscopy for GFP⁺ and CD45⁺ cells. The mean ± SEM percentage of GFP⁺ cells was calculated for total splenocytes (n = 4 per group). P < 0.05. C: Flow cytometry analysis of BM and splenic CD45⁺Col⁺ cells from young and aged Col-GFP mice revealed increased expression of CCR2 and CCR7. D: CD45⁺Col⁺ cells isolated from spleens of LPS-treated young and aged Col-GFP mice were analyzed using the mRNA microarray.