title: Selective depletion of Vbeta2+CD8+ T cells in peripheral blood from rheumatic heart disease patients.
abstract: Acute rheumatic fever (ARF) and its chronic valvular sequelae are the delayed consequence of a pharyngeal infection with group A Streptococcus (GAS). Several GAS proteins have been shown to be superantigens, raising the possibility that the expansion or deletion of T cells expressing specific Vbeta regions might play a role in the pathogenesis of ARF or chronic rheumatic heart disease (RHD). We therefore analyzed by four-color flow cytometry, the Vbeta repertoire on CD3, CD4 and CD8 T cells from four ARF patients, 10 RHD patients and also nine healthy controls. A selective depletion of Vbeta2+ T cells was found only in the CD8 subset of chronic RHD patients. This is of interest since a number of GAS superantigens exert their effects on Vbeta2+ cells and because only CD8+ T cells from ARF and RHD patients undergo anergy in response to GAS superantigens. Our results suggests that an ongoing immune process is present in RHD patients and that CD8+ T cells may have an important immunoregulatory role in the pathogenesis of the disease.
authors.affiliation: Facultad de Medicina, Universidad de los Andes, Avda. San Carlos de Apoquindo 2200, Las Condes, Santiago, Chile.
authors.forename: F
authors.initials: F
authors.lastname: Carrión
authors.forename: M
authors.initials: M
authors.lastname: Fernandez
authors.forename: M
authors.initials: M
authors.lastname: Iruretagoyena
authors.forename: L E
authors.initials: LE
authors.lastname: Coelho Andrade
authors.forename: M
authors.initials: M
authors.lastname: Odete-Hilário
authors.forename: F
authors.initials: F
authors.lastname: Figueroa
mesh_terms: D000293:Adolescent; D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism*; D002455:Cell Division / Q000502:physiology; D006801:Humans; D016131:Lymphocyte Subsets / Q000378:metabolism; D012214:Rheumatic Heart Disease / Q000378:metabolism*