Abundant cytoprotective, organelle-homeostatic autophagy in primary amyloidogenic PCs. Assessment of autophagy and its role in primary AL PCs. (A) Proportion of cell death upon 24 hours of treatment with the distal autophagic inhibitor, leupeptin (Leup; 10 µM) and Btz (2 nM), alone or in combination, as assessed by cytofluorimetric analysis upon labeling with propidium iodide and fluorescent-conjugated antibody anti-syndecan 1 and annexin V. Each dot represents 1 of 10 AL patients. (B) EM analysis of autophagosomes in primary AL (left) and MM (right) PCs (representative images). (C) EM quantification of ER-phagy (left) and mitophagy (right) in AL and MM PCs. The histograms show the average numbers ± standard error of ER- and mitochondria-containing autophagosomes per PC in each AL and MM patient (>20 PCs per AL and MM patient; 5 patients per group). *P < .05 (Student t test).