title: Thyroid-infiltrating B lymphocytes in Graves' disease are related to marginal zone and memory B cell compartments.
abstract: B lymphocytes that infiltrate the thyroid (Thy-B cells) in Graves' patients appear to be implicated in the pathophysiology of this disorder. The goal of the present study was to examine the nature of these Thy-B cells. To this end, Thy-B lymphocytes were isolated from surgical thyroidal samples, and their phenotype was determined by using mouse monoclonal antibodies (mAb) directed against a wide variety of surface markers, followed by flow cytometry multicolor analysis. The results show that most Thy-B cells (approximately 60%) exhibited IgM(+) IgD(low to -) surface immunoglobulin (Ig) profile, whereas the minor cell fraction (approximately 30%) consisted of switched IgG(+) memory B lymphocytes. Thy-B cells expressed low levels of CD5, CD23, and CD62L, which distinguished them from the resting B-cell pool, the major B-cell subset in the blood. In addition, they lacked CD38, CD10, and CD71, characteristic molecules for the germinal center B lymphocytes. In addition, Thy-B lymphocytes showed peculiar patterns both of adhesion molecules (CD62L(-), CD44(intermediate)), and of activation molecules (CD69(+), CD80(+), and, in part, CD95(+)). Taken together, these results suggest that the Thy-B lymphocyte subset consists of a combination of IgM(+) B cells resembling marginal zone B lymphocytes, and isotype-switched memory B cells.
authors.affiliation: Servicio de Inmunología, Hospital Universitario Puerta del Mar, Cádiz, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Segundo
authors.forename: C
authors.initials: C
authors.lastname: Rodríguez
authors.forename: A
authors.initials: A
authors.lastname: García-Poley
authors.forename: M
authors.initials: M
authors.lastname: Aguilar
authors.forename: I
authors.initials: I
authors.lastname: Gavilán
authors.forename: C
authors.initials: C
authors.lastname: Bellas
authors.forename: J A
authors.initials: JA
authors.lastname: Brieva
mesh_terms: D000293:Adolescent; D000328:Adult; D015703:Antigens, CD / Q000378:metabolism; D016175:B-Lymphocyte Subsets / Q000502:physiology; D001402:B-Lymphocytes / Q000473:pathology / Q000502:physiology*; D015415:Biomarkers; D015815:Cell Adhesion Molecules / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006111:Graves Disease / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D007150:Immunohistochemistry; D007156:Immunologic Memory / Q000502:physiology*; D010641:Phenotype; D013961:Thyroid Gland / Q000473:pathology / Q000503:physiopathology*
chemical_list: D015703:Antigens, CD; D015415:Biomarkers; D015815:Cell Adhesion Molecules