Fig. 3.

mRNA expression of genes associated with B-cell activation, survival, and antigen production is upregulated in the BM of aged mice. (A) The mRNA levels of genes involved in B-cell development and function (A), B-cell activating factor (BAFF), and BAFF receptor (BAFF-R) (B), and MHC class II molecules. (C) Immunohistochemical staining of CD74 in decalcified femur sections from age-matched mice. Scale bars: top, 200 μm; bottom, 50 μm. (D) Quantification of CD74⁺ cells per mm² in decalcified femur sections from age-matched mice, mean ± SE (n = 10, *P < 0.05).