Effect of lymphotoxin-beta receptor-immunoglobulin fusion protein (LTβR-Ig) treatment on follicular dendritic cell (FDC) networks and chemokines. (a) Photomicrographs of immunohistochemical staining for FDC networks and CXCL13 and CCL19 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. Arrowheads indicate sites of chemokine staining. Bars = 100 μm. A comparison of relative mRNA expressions of CXCL13 (b), CCL19 (c), and CCL21 (d) in salivary glands of the baseline group (NT9 group) and the oldest mice (19 weeks old) treated with either LTβR-Ig or MOPC 21 or untreated. Salivary glands from seven or eight mice per group were used in this analysis. Quantitative polymerase chain reactions (Q PCRs) using RNA from each organ were run in quadruplicate, and the mean signal was normalized to the glyceraldehyde 3-phosphate dehydrogenase (GAPDH). Data are presented as the mean of the values for the replicate organs (seven or eight organs per point) and the standard deviation. The differences between LT19 and controls were not significant.