FDC FcgRII downregulation a "bottle neck" in aging.

The Panel shows representative sections of draining lymph nodes labeled with FDC-M1 for FDC reticula from days 0 through 10 after antigenic challenge. The size of networks (reticula) were determined and the kinetics of change is shown on graph 1. Graphs 2 and 3 show the density and size of reticula after labeling with anti-CR1,2. Note that there is no significant difference in size of the FDC networks between young and old mice for FDC-M1 or CR1,2. The density of expression of CR1,2 on FDCs is also the same in young and old mice. [REF1] [REF2]