Figure 5.

Aged mice have elevated serum and mucosal immunoglobulin levels and elevated IgA production by ILFs. Serum and feces were collected from aged and young mice and immunoglobulin levels were measure by ELISA. Aged mice had significantly elevated serum IgA (panel a), IgG (panel b) and IgM (panel c). Aged mice also displayed elevated fecal IgA (panel d) and culture of ILF cellular populations revealed that IgA production was increased in ILFs from aged mice (panel e). n = 12 or more for serum Ig measurements, n = 3 or more for fecal Ig levels. n = 2 or more independent experiments for culture supernatant Ig levels. * = p < 0.05