Effect of lymphotoxin-beta receptor-immunoglobulin fusion protein (LTβR-Ig) treatment on B-cell zones, T-cell zones, and high endothelial venules (HEVs). (a) Photomicrographs of immunohistochemical staining for B cells, T cells, and HEVs in the submandibular glands. Three or four mice from each of the 10 groups were randomly selected for immunohistochemistry. Data shown here are representative examples of control mice (19 weeks old) that were not treated (NT19) or that were treated with 10 injections of mouse monoclonal IgG1 (MOPC 21) (MO19) and of mice treated with 10 injections of LTβR-Ig (LT19). Bars = 100 μm. (b) Proportion of B-cell zones to the total area of the gland (that is, the B-cell ratio index). (c) Proportion of T-cell zones to the total area of the gland (that is, the T-cell ratio index). (d) Number of HEVs to the total area of the gland. Each of the 10 groups had three or four randomly selected mice for each staining and analysis. Legend applies to frames (b-d). Bars indicate the mean and the standard error of the mean.