Insight into the protein composition of immunoglobulin light chain deposits of eyelid, orbital, and conjunctival amyloidosis.

ABSTRACT: Amyloidosis is a disorder characterized by the formation of extracellular amyloid deposits. Immunoglobulin light-chain amyloidosis the most common form of amyloidosis can appear as a local disorder presented with mild symptoms or as a life threatening systemic disease. Identification of the proteins forming amyloid fibrils is essential for the diagnosis of the disease and knowledge about the overall protein composition of the deposits may lead to a larger understanding of the deposition events thereby facilitating a more detailed picture of the molecular pathology. In this study, we investigated the protein composition of AL amyloid deposits isolated from human eyelid, conjunctival and orbital specimens. Deposits and internal control tissue (patient tissue without apparent deposits) were procured by laser capture microdissection. Proteins in the captured amyloid and control samples were identified by liquid chromatography tandem mass spectrometry and subsequently quantified using the label-free mass spectrometry quantification method exponential modified Protein Abundance Index. Immunoglobulin light chain kappa or lambda was revealed to be the most predominant protein in the amyloid deposits. In addition, the protein profiles identified apolipoprotein E and serum amyloid P component to be associated with the immunoglobulin light chain deposits across all three tissues analyzed. The method used in this study provides high sensitivity and specificity of typing amyloidosis and may provide additional information on the pathology of amyloidosis.

INSTRUMENT(S): TripleTOF 5600

ORGANISM(S): Homo Sapiens (human)

TISSUE(S): Eyelid, Orbit, Conjunctiva

SUBMITTER: Nadia Sukusu Nielsen  

LAB HEAD: Jan J. Enghild

PROVIDER: PXD000743 | Pride | 2014-05-29

REPOSITORIES: Pride