PLN architecture and cellularity of lymphoid organs in WT and ICAM-1/2^−/− mice. (A) Immunofluorescent staining of PLN sections of WT (i-v) and ICAM-1/2^−/− (vi-x) mice. i,vi: laminin (lam; blue), Thy1.2 (green), and B220 (red). Scale bar = 400 μm. ii,iii,vii,viii: laminin (lam; green) and ICAM-1 (red). Scale bar = 200 μm (ii,vii) or 40 μm (iii,viii). iv,v,ix,x: laminin (lam; green) and ICAM-2 (red). Scale bar = 200 μm (iv,ix) or 40 μm (v,x). (B-E) Absolute cell numbers per cervical, brachial, axillary, inguinal, paraaortal, and popliteal PLNs (B), MLN (C), PP (D), and spleen (E) of WT and ICAM-1/2^−/− mice, represented as mean plus or minus SEM pooled from 3 (PLN, MLN, spleen) or 4 (PP) independent experiments. n.s. indicates not significant. **P < .01; ***P < .0001.