Tumors induced by 8A4 cells grafted to mice.

Immunofluorescence microscopy with antimouse Ig conjugate (A, original magnification ×1000) and light microscopy (B, semi-thin section, toluidine blue staining, original magnification ×1000) showed numerous polymorphic crystals located in tumor cell cytoplasms. (C and D) Electron microscopy showed osmiophilic and highly organized crystalline inclusions in rough ergastoplasm cisternae with a periodicity of 12 nm (C, original magnification ×6000; D, ×25 000).