Sections immunostained for concomitant localization of APP and IBA1 epitopes in representative cases of MVC (Case 21; a-b), blast (Case 1; c-d), and opiate overdose (Case 7; e-f). APP (brown) and IBA1 (blue) was detected sequentially by DAB and Vector blue, respectively, as described in Methods. Note that, in MVC (a-b) and blast (c-d) APP (+) swellings and bulbs colocalise with deramified or phagocytic microglia, whereas in opiate overdose (e-f) they do not. Panels b, d, and f are magnifications of framed areas in a,c, and e, respectively. Size bars: 50 (a, c and e) and 100 (b, d, and f) μm.