TTR and amyloidosis: To assess whether V122I TTR induced caspase 3/7 activation, a marker of apoptosis or programmed cell death that is known to be activated in TTR amyloidosis patients [35] and in other TTR tissue culture models [12,15,38], we used cell lysates from V122I, T119M and HBSS-treated cells to cleave the substrate Ac-DEVD-AFC as detailed in the experimental section.