Figure 9.

Demonstration of amyloid A in secondary amyloidosis and pneumococcal antigens in lobar pneumonia in archival material. Top panels (a,b): Splenic white pulp with amyloid A deposition. Bottom panels (c,d): pneumococcal antigens in lobar pneumonia showing diffuse neutrophilic infiltration. Left (a,c): H&E and Right (b,d): chromogenic immunostaining. The specimens were fixed in formalin for 70 years. Deposition of amyloid A protein is evident in the splenic white pulp (no pretreatment needed). Pneumococci phagocytized by neutrophils are visualized immunohistochemically after HIER.