title: Quantitative and functional analysis of CD69(+) NKG2D(+) T regulatory cells in healthy subjects.
abstract: T regulatory (Treg) cells have a key role in immune homeostasis and the pathogenesis of chronic inflammatory and autoimmune diseases. CD69 is an early leukocyte activation molecule that under steady state conditions is detected in a small proportion of lymphocytes in peripheral blood and lymphoid tissues. Although it has been reported that a subset of CD69(+) T cells behaves as Treg lymphocytes, the possible relationship between CD69(+) Treg cells and CD4(+)NKG2D(+) T lymphocytes, which also exert immunosuppressive activity, has not been explored. In this study, we analyzed the expression of CD69 and NKG2D by T lymphocytes from the peripheral blood of twenty-five healthy subjects by multi-parametric flow cytometry analysis, and their suppressive activity by an assay of inhibition of lymphocyte activation (CD40L expression) and proliferation (carboxyfluorescein partition assay). We found a very small percentage of CD4(+)CD69(+)NKG2D(+) T cells (median 0.002%, Q1-Q3, 0.001-0.004%), which also expressed TGF-β (Latency Associated Peptide or LAP) and IL-10, in all samples analyzed. These cells exerted an important in vitro suppressive effect on both activation and proliferation of T effector cells. Our data suggest that at very small numbers, CD4(+)CD69(+)NKG2D(+) lymphocytes seem to exert a relevant functional immune-regulatory role in healthy subjects.
authors.affiliation: Department of Immunology, School of Medicine, UASLP, San Luis Potosí, SLP, Mexico.
authors.forename: M
authors.initials: M
authors.lastname: Vitales-Noyola
authors.affiliation: Laboratory of Immunology, UAMZH, UASLP, Cd. Valles, SLP, Mexico.
authors.forename: L
authors.initials: L
authors.lastname: Doníz-Padilla
authors.affiliation: Department of Immunology, School of Medicine, UASLP, San Luis Potosí, SLP, Mexico.
authors.forename: C
authors.initials: C
authors.lastname: Álvarez-Quiroga
authors.affiliation: Department of Immunology, School of Medicine, UASLP, San Luis Potosí, SLP, Mexico.
authors.forename: A
authors.initials: A
authors.lastname: Monsiváis-Urenda
authors.affiliation: Laboratory of Immunology, UAMZH, UASLP, Cd. Valles, SLP, Mexico.
authors.forename: H
authors.initials: H
authors.lastname: Portillo-Salazar
authors.affiliation: Department of Immunology, School of Medicine, UASLP, San Luis Potosí, SLP, Mexico. Electronic address: rgonzale@uaslp.mx.
authors.forename: R
authors.initials: R
authors.lastname: González-Amaro
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000032:analysis*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000032:analysis*; D005260:Female; D006801:Humans; D037181:Lectins, C-Type / Q000032:analysis*; D018655:Lymphocyte Count; D008297:Male; D055655:NK Cell Lectin-Like Receptor Subfamily K / Q000032:analysis*; D050378:T-Lymphocytes, Regulatory / Q000502:physiology*; D000099192:CD69 Antigens
chemical_list: D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D037181:Lectins, C-Type; D055655:NK Cell Lectin-Like Receptor Subfamily K; D000099192:CD69 Antigens
keywords: CD69; Immune-regulation; NKG2D; T regulatory cells