MRL-lpr/lpr lymph node vasculature shows expansion and re-established quiescence with course of disease.

<p>MRL+/+ and MRL-lpr/lpr mice were examined at indicated ages; brachial lymph nodes were used for flow cytometry-based studies (A, C–E, G–J) and popliteal lymph nodes were used for VEGF determination (F). (A) Lymph node cellularity as determined by count of lymph node cells. (B) Serum anti-dsDNA IgG titers. (C) Number of endothelial cells per lymph node as determined by flow cytometry. “Total EC” = CD45^negCD31^pos cells; total endothelial cells are comprised of PNAd ^pos “HEV EC” and PNAd ^neg “nonHEV mixed EC.” (D) Endothelial cell proliferation rate as determined by the percent of endothelial cells that are BrdU+. (E) Number of proliferating (BrdU+) endothelial cells per lymph node. (F) VEGF levels in lymph nodes. Each symbol represents 1 mouse. (G) HEV trafficking efficiency. About 3×10⁷ CFSE-labeled splenocytes were intravenously injected into 3.5 month old mice at 30 minutes prior to sacrifice. HEV trafficking efficiency was defined as the number of CFSE-labeled splenocytes that entered the lymph node divided by the number of HEV endothelial cells. n = 3 mice per condition. Representative of 3 similar experiments. (H) Number of lymphocyte subsets over time. Cells were identified as follows: “B220+ T cells” were B220^posCD3^pos cells; “B220− T cells” were B220^negCD3^pos cells; “B cells” were B220^posCD3^neg cells. (I) Number of subsets of CD11c+ cells over time. (J) Ratio of CD11c^hi cells to CD11c^med cells over time. For A–E, H–J, n = 6 mice per condition over 3 experiments. For A–J, * = p<.05 and ** = p<.01 in comparison to the same measurement in the age matched MRL+/+ mice using t-test.