Human Immunoglobulin Light Chains λ Form Amyloid Fibrils and Granular Aggregates in Solution

Role of cis- and trans-interactions in manifestations of amyloidogenic properties of variable domains of Bence-Jones proteins TIM and LUS

“…All Bence Jones proteins under study were prepared using the routine method from 0.7 liter of the daily urine of patients with multiple myeloma [15]. Upon fractionation in 70% ammonium sulfate, the proteins were separated by ion exchange chromatography on DEAE Sephacel (10 mM Na 2 HPO 4 , pH 8.1, the NaCl linear gradient was 0 300 mM).…”

“…Dimers of variable domains connected by covalent bonds were obtained using the homobifunctional reagent bis(N hydroxysuccinimide suberate) ester (DSS) as described earlier in works [15,19]. The cross linked dimers and residual monomers were separated by gel fil tration on a column with Sephacryl S100 HR at low pro tein concentration (0.5 mg/ml), when the equilibrium of the fraction of residual free domains was sharply shifted to monomers.…”

Thermodynamic and Kinetic Characterization of a Germ Line Human λ6 Light-Chain Protein: The Relation between Unfolding and Fibrillogenesis

“…Fluorescence data were measured in a multiplate FLUOstar Optima fluorometer (BMG Labtech) at 3-min intervals with an excitation wavelength filter of 450 nm and an emission wavelength filter of 490 nm. (2) In the magnetic micro stir bar assay, 6 mL of protein solutions were incubated in flatbottomed screw-capped poplypropylene vials. Samples were continuously stirred at 250 rpm with Teflon-coated micro stir bars (2 mm × 10 mm) in a multipoint Variomag magnetic stirrer placed inside a Brinkman incubator set at 37°C.…”

“…It is known that amyloid fibers are not formed under conditions that favor the native or unfolded states. 2,5,7,9,10,17,[26][27][28][29] This suggests that conformational changes, such as the formation of folding intermediates, are required for fibril formation. In fact, it has been documented that mild unfolding conditions favor fibril formation; however, as opposed to other conformational diseases where folding intermediates have been fully characterized, [28][29][30] folding intermediates for light chains have been reported only for κ light chains in extreme pH conditions 7,9,12,13,31 and, more recently, in the presence of guanidine hydrochloride (GdnHCl).…”

Free immunoglobulin light chain (FLC) promotes murine colitis and colitis-associated colon carcinogenesis by activating the inflammasome

“…Historically, excess FLC was considered to be a bystander without any function. In recent years, growing evidence has indicated that FLC is significantly linked to the progression and severity of inflammatory diseases, and both covalent and noncovalent dimerization of FLC are closely associated with the formation of fibrillar deposit in many diseases 35, 39–41 . Early clinical reports regarded FLC as biomarkers of many inflammatory diseases, such as autoimmune disease, diabetes mellitus and CNS inflammation 42, 43 .…”