APOA4 and amyloidosis: It has been suggested [471,472] that at least some types of classical amyloidoses have a ‘proteome signature’ that would include serum amyloid P-component (SAP) and heparan sulphate proteoglycans (HSPG), as well as apolipoprotein A4, apolipoprotein E, and vitronectin (see also [62,473,474,475,476]), consistent with some kind of cross-seeding; interestingly, none of these was reported in either the Schofield or Kruger studies, though the latter three proteins were easily observed in normal clots (Figure 17).