Figure 2.

In vivo lymph node DC migration in aging. Groups of young mice (n=3) received 50 μl of equal numbers (2 × 10⁶) of CMPTX-labeled young DC and CFSE-labeled old DCs into their footpad hind. Popliteal draining LNs were excised 24 hrs later and the frequency of DC/node was assessed by fluorescent microscopy. (A) Representative photos (200X) showing young DCs in green, old DCs in red and the merge picture. (B) Close up (digital enlargement) of selected fields are also shown. Percent of red versus green DCs per field was derived from microscope examination data by counting at least 200 cells/group in randomly selected fields. (C) Similar experiments were done using 2 times (2×) and 3 times (3×) more old DCs than young DCs.