Chemical Analysis of Beta2-Microglobulin Derived Amyloid in Patients on Long-Term Hemodialysis
Amyloid deposits of a patient (KRO) who underwent peritoneal and longterm hemodialysis were chemically, immunochemically and immunohistochemically investigated. The amyloid fibrils from bone marrow were concentrated, dissolved in 80% and separated in 60% formic acid by HPLC according to size. Several different protein peaks were recovered, having molecular weights of approximately 24, 18, 12, and 7–10 kd. The largest fraction represented the void volume peak. All fractions reacted strongly with an antiserum directed against β2m+). N-terminal amino acid sequence analysis showed three different molecules, all derived from β2m: one with the intact N-terminus, a second and a third with either isoleucine in position 6 or serine in position 11 as N-terminus, respectively.
When compared with two additional AB-amyloids that were analysed similarly, two points seem important: (a) in all three cases fragmentation of β2m had occurred, and (b) this fragmentation was not random but in general lysine-specific; this was also the case with one of two AB-protein fragments in patient KRO. These results suggest further, that during the formation of AB-amyloid also limited proteolysis occurs.
Immunohistochemical analysis of vascular amyloid in heart and joint capsule showed antigenic differences when investigated with a panel of anti-amyloid antisera. While in the periarticular tissue only anti-β2m reacted, in heart amyloid both, anti-β2m and anti-AA were reactive. This finding raises the possibility that two different amyloid types can reside in one individual simultaneously. Both amyloids are associated with longterm hemodialysis, but each is induced by probably a different mechanism.
KeywordsCarpal Tunnel Syndrome Amyloid Deposit Amyloid Fibril Fibril Protein Vascular Amyloid
Unable to display preview. Download preview PDF.
- 1.T. Bardin, J. Zingraff, D. Kuntz, T. Drüeke, Dialysis-related amyloidosis (Editorial), Nephrol. Dial. Transplant, 1:151 (1986).Google Scholar
- 2.F. Gejyo, T. Yamada, S. Odani, Y. Nakagawa, T. Kunitomo, H. Kataoka, M. Suzuki, Y. Hirasawa, T. Shirahama, A.S. Cohen, K. Schmid, A new form of amyloid protein associated with chronic hemodialysis was identified as β2-microglobulin, Biochem. Biophys. Res. Comm. 1929:701 (1985).CrossRefGoogle Scholar
- 8.R.P. Linke, W.B.J. Nathrath, M. Eulitz, Classification of amyloid syndromes from tissue sections using antibodies against various amyloid fibril proteins: report of 142 cases, in: “Amyloidosis”, G.G. Glenner et al. (eds.), Plenum Press, New York (1986).Google Scholar
- 12.R.M. Mewick, M.W. Hunkapillar, L.W. Hood, W.J. Dreyer, A gas liquid-solid phase peptide and protein sequenator, Biol. Chem. 256:7990 (1981).Google Scholar
- 13.R.P. Linke, K.L. Heilmann, W.B.J. Nathrath, M. Eulitz, Identification of amyloid A protein in a sporadic Muckle-Wells syndrome. N-terminal amino acid sequence analysis after isolation from formalin-fixed tissue, Lab. Invest. 48:698 (1983).Google Scholar
- 14.R.P. Linke, Immunochemical typing of amyloid deposits after micro-extraction from biopsies, Appl. Pathol. 3:8 (1985).Google Scholar