High-molecular-mass proteins in haemodialysis-associated amyloidosis.
1. Protein constituents were determined in eight amyloid deposits from eight patients (five male and three female), 53 +/- 4 years of age, treated by haemodialysis for 9-20 years using only cuprophane membranes and operated for carpal tunnel syndrome. 2. Soluble proteins were removed by solubilization in phosphate-buffered saline after osmotic lysis. The proteins of the insoluble fibrils were characterized by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and two-dimensional gel electrophoresis, and immunologically identified by Western blotting. 3. In addition to beta 2-microglobulin, alpha 2-macroglobulin was identified in the fibrillar material. The presence of these two proteins in amyloid deposits was confirmed by immunofluorescent microscopic studies. 4. Our data confirm the presence of beta 2-microglobulin in haemodialysis-associated amyloidosis, and also suggest a possible role for alpha 2-microglobulin: it may protect beta 2-microglobulin from proteolytic digestion, leading to its accumulation in intact form and to amyloid fibril formation.
Argiles
A
A
INSERM Unit 249, Centre de Recherche Biochimie Macromoléculaire, CNRS, Montpellier, France.
Mourad
G
G
Axelrud-Cavadore
C
C
Watrin
A
A
Mion
C
C
Cavadore
J C
JC
D000682:Amyloid / Q000032:analysis*; D000686:Amyloidosis / Q000209:etiology / Q000378:metabolism*; D015153:Blotting, Western; D002349:Carpal Tunnel Syndrome / Q000209:etiology; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008875:Middle Aged; D008970:Molecular Weight; D011506:Proteins / Q000032:analysis*; D006435:Renal Dialysis / Q000009:adverse effects*; D000511:alpha-Macroglobulins / Q000032:analysis; D001613:beta 2-Microglobulin / Q000032:analysis
D000682:Amyloid; D011506:Proteins; D000511:alpha-Macroglobulins; D001613:beta 2-Microglobulin