title: Light chain (κ/λ) ratio of GM-CSF autoantibodies is associated with disease severity in autoimmune pulmonary alveolar proteinosis.
abstract: Previous studies demonstrated that antigranulocyte colony-stimulating factor autoantibody (GMAb) was consistently present in patients with autoimmune pulmonary alveolar proteinosis (aPAP), and, thus, represented candidature as a reliable diagnostic marker. However, our large cohort study suggested that the concentration of this antibody was not correlated with disease severity in patients. We found that the κ/λ ratio of GMAb was significantly correlated with the degree of hypoxemia. The proportion of λ-type GMAb per total λ-type IgG was significantly higher in severely affected patients than those in mildly affected patients, but the proportion of κ-type was unchanged. The κ/λ ratio was significantly correlated with both KL-6 and SP-D, which have been previously reported as disease severity markers. Thus, the light chain isotype usage of GMAb may not only be associated with the severity of aPAP, but may also represent a useful disease severity marker.
authors.affiliation: Bioscience Medical Research Center, Niigata University Medical and Dental Hospital, Niigata, Japan; Department of Respiratory Medicine, Nippon Medical School, Tokyo, Japan. Electronic address: takahitonei@gmail.com.
authors.forename: Takahito
authors.initials: T
authors.lastname: Nei
authors.forename: Shinya
authors.initials: S
authors.lastname: Urano
authors.forename: Yuko
authors.initials: Y
authors.lastname: Itoh
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Kitamura
authors.forename: Atsushi
authors.initials: A
authors.lastname: Hashimoto
authors.forename: Takahiro
authors.initials: T
authors.lastname: Tanaka
authors.forename: Natsuki
authors.initials: N
authors.lastname: Motoi
authors.forename: Chinatsu
authors.initials: C
authors.lastname: Kaneko
authors.forename: Ryushi
authors.initials: R
authors.lastname: Tazawa
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Nakagaki
authors.forename: Toru
authors.initials: T
authors.lastname: Arai
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Inoue
authors.forename: Koh
authors.initials: K
authors.lastname: Nakata
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001323:Autoantibodies / Q000097:blood*; D001327:Autoimmune Diseases / Q000097:blood / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology; D015415:Biomarkers / Q000097:blood; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000037:antagonists & inhibitors / Q000097:blood / Q000276:immunology*; D006801:Humans; D007145:Immunoglobulin kappa-Chains / Q000097:blood* / Q000276:immunology; D007146:Immunoglobulin lambda-Chains / Q000097:blood* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D018396:Mucin-1 / Q000097:blood; D011649:Pulmonary Alveolar Proteinosis / Q000097:blood / Q000175:diagnosis / Q000276:immunology* / Q000473:pathology; D037663:Pulmonary Surfactant-Associated Protein D / Q000097:blood; D012720:Severity of Illness Index
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains; C060192:MUC1 protein, human; D018396:Mucin-1; D037663:Pulmonary Surfactant-Associated Protein D; D016178:Granulocyte-Macrophage Colony-Stimulating Factor
keywords: Anti-GM-CSF autoantibody; Light chain ratio; Pulmonary alveolar proteinosis