Number of leukocytes in lacrimal glands is reduced by treatment with LTBR-Ig. Representative photomicrographs of hematoxylin and eosin stained paraffin tissue-sections (a to c) and tissue-sections stained with anti-B220 and immuno-peroxidase (dark brown) (d to h) from NOD mice that were not treated (NT) or were treated from 8 to 16 weeks of age with MOPC-21 control antibody or with LTBR-Ig. Arrows (a,b) denote aggregations of leukocyte nuclei (dark blue). Bar equals 100 micron. Specificity control for anti-B220 staining of a section from a untreated mouse lacrimal gland (g); the area of the inset box in (g) is shown at higher magnification in (h) or an adjacent section stained without the primary antibody (i); arrowhead marks same location in (h,i). FACS analysis of leukocytes isolated from lacrimal glands of mice treated with MOPC-21 control antibody (n = 8 glands) or LTBR-Ig (n = 8 glands) (j). Mean and standard deviation of total CD45 positive leukocytes, total number of B220 positive cells (B-cells) and of CD3 positive cells (T-cells) are indicated for each treatment type. This experiment was repeated four times. Statistical significance was calculated by two-tailed T-test. FACS, flow cytometry; LTBR-Ig, lymphotoxin-beta receptor-mouse immunoglobulin (Fc), NOD, non-obese diabetic.