Histones accumulate at the endothelial surface in the cerebral microvasculature and are associated with sequestration. (A,B) Fatal definitive CM cases showing histone staining in close proximity with endothelial cell luminal surface and marks host cell nuclei (red arrow) as well parasite nuclei in IE (white arrow). (B) Enlarged image of panel A to show luminal histone staining (black arrows) as well as IE with histone staining. (C) Fatal parasitemic non-CM comatose case (Parasitemic) with no histone endothelial membrane binding; histone staining can be seen in mammalian cell nuclei (red arrows). (D) Luminal histone staining is markedly increased in definitive CM (n = 17) compared with parasitemic non-CM cases (Parasitemic, n = 6) or fatal nonmalarial comatose illness CM cases (nonmalaria; n = 5). (E) In definitive CM cases (n = 17); there is a strong association between the degree of sequestration and the presence and strength of histone membrane staining (determined by ordinal logistic regression). Red staining is to antihistone H3 using Vector Red. Images were acquired at ×600 using an oil immersion lens.