Fig. 1

Typical morphological characteristics of immune alveolitis on bronchoalveolar lavage. Activated lymphocytes (thin black arrow) (A), desquamation of macrophages into cohesive clusters (thick black arrow) (B), epithelioid transformation of macrophages and foamy macrophages (intra-cytoplasmic vacuoles) (red arrow) (C). May-Grünwald Giemsa ×40