Figure 3

Immunogold transmission electron microscopy (TEM) using an α-synuclein primary antibody on pars intermedia tissue confirms presence of fibrils in a PPID-affected horse. (A) TEM image from the pars intermedia of an PPID-affected horse without use of the primary antibody consists of background staining of the secondary antibody. (B) TEM image of the pars intermedia of an aged horse shows an immunogold labeling similar to background straining. (C) TEM image of the pars intermedia of a PPID-affected horse exhibits immunogold labeling. (D) TEM image of the pars intermedia of a PPID-affected horse contains a fibril with minimal immunogold labeling in the extracellular milieu (Scale bars, 200 nm).