Dataset Information

IgG subclasses in cryoglobulins: link to composition and clinical manifestations.

ABSTRACT: BACKGROUND:Cryoglobulins (CG) are immunoglobulins which precipitate at low temperature. The analysis of IgG subclass composition of CG is poorly reported. The aim of this study was to determine the subclasses of IgG-containing type I and mixed type II and III CG in relation to clinical manifestations. METHODS:Out of a previous series of 1675 patients, inclusion criteria were a cryoprecipitate >?1?mL and a total IgG?>?300?mg/L. IgG subclasses were quantified by immunoturbidimetry, rheumatoid factor (RF), and C4 by immunonephelometry. Clinical parameters were collected from hospital charts. RESULTS:CG samples from 86 patients were included, 10 type I CG and 76 mixed CG. Type I CG subclasses were IgG1 (6/10) and IgG2/IgG3 (4/10), never IgG4. IgG subclass in type II vs. III CG were 73.3?±?15.2% vs. 52.5?±?20.7% for IgG1 (p?

SUBMITTER: Kolopp-Sarda MN

PROVIDER: S-EPMC7659205 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

IgG subclasses in cryoglobulins: link to composition and clinical manifestations.

Kolopp-Sarda Marie N MN Azevedo Pedro Ming PM Miossec Pierre P

Arthritis research & therapy 20201112 1

<h4>Background</h4>Cryoglobulins (CG) are immunoglobulins which precipitate at low temperature. The analysis of IgG subclass composition of CG is poorly reported. The aim of this study was to determine the subclasses of IgG-containing type I and mixed type II and III CG in relation to clinical manifestations.<h4>Methods</h4>Out of a previous series of 1675 patients, inclusion criteria were a cryoprecipitate > 1 mL and a total IgG > 300 mg/L. IgG subclasses were quantified by immunoturbidimetry, ...[more]

PMID: 33183349

Similar Datasets

Project description:Membranous nephropathy (MN) is an autoimmune disease caused by binding of circulating antibodies to podocyte antigens in the kidney. For decades and still today primary MN has been considered to have an unspecified IgG4-driven autoimmune genesis, while secondary MN has been associated with other diseases, most notably cancer, and not linked to IgG4. Immunologic mechanisms of primary and malignancy-associated MN are assumed to be different, however, this has never been systematically evaluated. The identification of Phospholipase A2 Receptor 1 (PLA2R1) and Thrombospondin Type-1 Domain-Containing 7A (THSD7A) as target antigens in MN allows a pathogenesis-driven differential diagnosis. Recent data showing a molecular link between increased THSD7A-expression in tumors and THSD7A-antibody positive MN suggest a similar pathogenesis of malignancy-associated and primary MN. In order to better define the underlying immunologic processes, we systematically analyzed circulating antigen-specific IgG subclasses in the serum of 76 patients with PLA2R1-associated MN and 41 patients with THSD7A-associated MN in relationship to concurrent malignancy and disease outcome. Twenty-three patients in the study had malignancy-associated MN. We analyzed antigen-specific IgG subclasses in the serum of all patients at baseline and in 55 patients during follow-up by Western blot applying antigens derived from human kidney and lung. At baseline all 117 patients were positive for IgG4-antibodies against either PLA2R1 or THSD7A, while IgG3, IgG1, and IgG2-antibodies were found in 87, 72, and 26% of patients, respectively. There were no differences in the IgG subclass distribution between patients with primary vs. cancer-associated MN and no association with disease outcome. Moreover, levels of antigen-specific IgG4-antibodies were not different between primary and malignancy-associated MN and levels of all IgG subclasses did not differ between these groups. Both podocytes and lung bronchioles showed expression of both PLA2R1 and THSD7A when analyzed by immunofluorescence and Western blot. Every antigen-specific IgG subclass showed identical binding in both organs and autoantibodies bound the respective antigen only under non-reducing conditions. We conclude that antigen-specific IgG subclasses do not differentiate primary from malignancy-associated MN or predict disease prognosis. These data support the view that one common pathway may lead to primary and cancer-associated MN induced by PLA2R1- or THSD7A-antibodies.

Dataset Information

IgG subclasses in cryoglobulins: link to composition and clinical manifestations.

Publications

IgG subclasses in cryoglobulins: link to composition and clinical manifestations.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets