F4/80⁺ cells in liver, kidney, skin, and synovial membrane.

Tissues from wild-type,Csf1^op/Csf1^op, andCsf1r⁻/Csf1r⁻ mice were immunostained with a monoclonal antibody to F4/80 that selectively stains macrophages and were counterstained with hematoxylin. Sections of (A-C) 2-day-old livers, (D-E) 2-week-old kidneys showing macrophages surrounding the glomeruli (GL) and tubules (T) of wild-type mice (D), (F-I) 2-day-old skin showing immunostaining of both Langerhans cells (LC) and dermal macrophages (DM) from wild- type mice, and (J-L) longitudinal sections of 2-week-old knee joints in the region of the synovial membrane (S) showing immunostaining of cells in the wild-type synovial membranes. Note the more rounded and less dendritic appearance of the F4/80⁺ cells in the tissues of theCsf1^op/Csf1^op andCsf1r⁻/Csf1r⁻ mice, previously reported forCsf1^op/Csf1^op mice. Bar, 50 μm. Original magnification A-L, × 400.