FAT TISSUE ANALYSIS BY CONGO RED METHOD AND BY AMYLOID A PROTEIN QUALIFICATION IN CLINICAL AA AMYLOIDOSIS

摘要

Quantification of amyloid A protein can be used to detect AA amyloid in fat tissue (1). The method confirms the AA-type of amyloid and can be automated to become observer-independent.OBJECTIVETo study the sensitivity of amyloid A protein quantification and Congo red method in fat tissue of patients with clinical AA amyloidosis.PATIENTS AND METHODSAbdominal subcutaneous fat tissue of patients was analysed at the start of the phase ll/lll clinical trial with Fibriilex~(TM), a GAG-mimetic drug. All patients had AA amyloidosis proven by a biopsy positively stained with Congo red as well as positive anti-AA immunohistology. All patients had renal symptoms, i.e. proteinuria of >=1 g/day or diminished creatinine clearance between 20 and 60 ml/min.Congo red stained slides (CR) were scored semi-quantitatively from 0 to 3+.Amyloid A protein in fat tissue was quantified by ELISA using murine monoclonal anti-human SAA antibodies Reu86.1 and Reu86.5 (Hycult Biotechnology, Uden, The Netherlands; Amyloid A protein reference range <12.6 ng/mg fat tissue) (1).