title: Molecular study of an IgG1kappa cryoglobulin yielding organized microtubular deposits and glomerulonephritis in the course of chronic lymphocytic leukaemia.
abstract: Glomerulonephritis with organized microtubular monoclonal immunoglobulin deposits (GOMMID) and glomerulonephritis related to type I cryoglobulin are well-known but rare complications of B cell derived chronic lymphocytic leukaemia. In these disorders, monoclonal Ig have never been studied at the molecular level. We conducted a pathological and molecular analysis in a patient with chronic lymphocytic leukaemia, glomerulonephritis and a single circulating monoclonal Ig. Unusual IgG1kappa kidney deposits were observed. The heavy and light chain variable region sequences of that cryoprecipitating monoclonal Ig were characterized. Light microscopy revealed glomerulonephritis typical of cryoglobulinaemia, with neutrophil and macrophage infiltration, endocapillary hyperplasia and few protein thrombi. Electron microscopic study clearly evidenced numerous subepithelial mixed granular and organized deposits with a unique microtubular organization, reminiscent of the GOMMID. The Ig molecule sequence revealed alterations of charge and hydrophobicity potentially promoting a crystal-like aggregation and the aggregation of microtubules. This description suggests that common mechanisms are involved in various forms of precipitation and/or deposition of complete Ig molecules, with a variable extent of organization and with a possible overlap between pathological patterns of either glomerulonephritis with microtubular deposits or type I cryoglobulinic glomerulonephritis.
authors.affiliation: Department of Immunology (CNRS UMR6101), University Hospital, Limoges, France.
authors.forename: H R
authors.initials: HR
authors.lastname: Galea
authors.forename: F
authors.initials: F
authors.lastname: Bridoux
authors.forename: J-C
authors.initials: JC
authors.lastname: Aldigier
authors.forename: F
authors.initials: F
authors.lastname: Paraf
authors.forename: D
authors.initials: D
authors.lastname: Bordessoule
authors.forename: G
authors.initials: G
authors.lastname: Touchard
authors.forename: M
authors.initials: M
authors.lastname: Cogné
mesh_terms: D000595:Amino Acid Sequence; D003449:Cryoglobulinemia / Q000209:etiology* / Q000276:immunology / Q000473:pathology; D003450:Cryoglobulins / Q000737:chemistry* / Q000302:isolation & purification; D003460:Crystallization; D005921:Glomerulonephritis / Q000209:etiology* / Q000276:immunology / Q000473:pathology; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D007074:Immunoglobulin G / Q000737:chemistry* / Q000302:isolation & purification; D007143:Immunoglobulin Heavy Chains / Q000737:chemistry; D007147:Immunoglobulin Light Chains / Q000737:chemistry; D007135:Immunoglobulin Variable Region / Q000737:chemistry; D007145:Immunoglobulin kappa-Chains / Q000737:chemistry* / Q000302:isolation & purification; D007668:Kidney / Q000276:immunology / Q000473:pathology; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000150:complications / Q000276:immunology*; D008297:Male; D008854:Microscopy, Electron; D008870:Microtubules / Q000648:ultrastructure*; D008875:Middle Aged; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000737:chemistry* / Q000276:immunology; D011487:Protein Conformation; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid; D055672:Static Electricity
chemical_list: D003450:Cryoglobulins; D007074:Immunoglobulin G; D007143:Immunoglobulin Heavy Chains; D007147:Immunoglobulin Light Chains; D007135:Immunoglobulin Variable Region; D007145:Immunoglobulin kappa-Chains; D009363:Neoplasm Proteins