title: Vitamin D supplementation effects on FoxP3 expression in T cells and FoxP3+/IL-17A ratio and clinical course in systemic lupus erythematosus patients: a study in a Portuguese cohort.
abstract: Systemic lupus erythematosus (SLE) is a systemic autoimmune disease with multi-organ inflammation, linked to loss of immune tolerance to self-antigens and the production of a diversity of autoantibodies, with a negative impact on the patients' quality of life. Regulatory T cells have been reported as deficient in number and function in SLE patients. However, some authors also described an enrichment of this cell type. The hypothesis that certain forms of autoimmunity may result from a conversion of Treg cells into a Th17 cell phenotype has been suggested by some studies. In fact, in SLE patients' sera, the IL-17 levels were observed as abnormally high when compared with healthy individuals. Environmental factors, such as vitamin D, that is considered a potential anti-inflammatory agent, combined with genetic and hormonal characteristics have been associated with SLE phenotype and with disease progression. The aim of this study was to evaluate the effect of vitamin D supplementation on FoxP3 expression and IL-17A-producing T cells, through FoxP3+/IL-17A ratio. Additionally, disease evolution, serum vitamin D levels, serum autoantibodies levels and calcium metabolism (to assure safety) were also studied. We assessed 24 phenotypically well-characterized SLE patients. All patients were screened before vitamin D supplementation and 3 and 6 months after the beginning of this treatment. Peripheral blood lymphocyte's subsets were analysed by flow cytometry. Serum 25(OH)D levels significantly increased under vitamin D supplementation (p = 0.001). The FoxP3+/IL-17A ratio in SLE patients after 6 months of vitamin D supplementation was higher than that in the baseline (p < 0.001). In conclusion, this study demonstrated that vitamin D supplementation provided favourable, immunological and clinical impact on SLE.
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal. antmarinho@hotmail.com.|Unidade Imunologia Clínica, Centro Hospitalar do Porto, Hospital Santo António, Largo Prof. Abel Salazar, 4099-001, Porto, Portugal. antmarinho@hotmail.com.
authors.forename: António
authors.initials: A
authors.lastname: Marinho
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.
authors.forename: Cláudia
authors.initials: C
authors.lastname: Carvalho
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.
authors.forename: Daniela
authors.initials: D
authors.lastname: Boleixa
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.
authors.forename: Andreia
authors.initials: A
authors.lastname: Bettencourt
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.
authors.forename: Bárbara
authors.initials: B
authors.lastname: Leal
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.|Serviço de Imunologia, Centro Hospitalar do Porto, Hospital Santo António, Porto, Portugal.
authors.forename: Judite
authors.initials: J
authors.lastname: Guimarães
authors.affiliation: Serviço de Imunologia, Centro Hospitalar do Porto, Hospital Santo António, Porto, Portugal.
authors.forename: Esmeralda
authors.initials: E
authors.lastname: Neves
authors.affiliation: Departamento de Patologia Clínica, Centro Hospitalar do Porto, Hospital Santo António, Porto, Portugal.
authors.forename: José Carlos
authors.initials: JC
authors.lastname: Oliveira
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.|Unidade Imunologia Clínica, Centro Hospitalar do Porto, Hospital Santo António, Largo Prof. Abel Salazar, 4099-001, Porto, Portugal.
authors.forename: Isabel
authors.initials: I
authors.lastname: Almeida
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.|Unidade Imunologia Clínica, Centro Hospitalar do Porto, Hospital Santo António, Largo Prof. Abel Salazar, 4099-001, Porto, Portugal.
authors.forename: Fátima
authors.initials: F
authors.lastname: Farinha
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.
authors.forename: Paulo P
authors.initials: PP
authors.lastname: Costa
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.|Unidade Imunologia Clínica, Centro Hospitalar do Porto, Hospital Santo António, Largo Prof. Abel Salazar, 4099-001, Porto, Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Vasconcelos
authors.affiliation: UMIB, Instituto de Ciências Biomédicas de Abel Salazar (ICBAS), UPorto, Porto, Portugal.
authors.forename: Berta M
authors.initials: BM
authors.lastname: Silva
mesh_terms: D000328:Adult; D000974:Antibodies, Antinuclear / Q000097:blood; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology*; D002118:Calcium / Q000097:blood; D003176:Complement C3 / Q000276:immunology; D019587:Dietary Supplements; D005260:Female; D051858:Forkhead Transcription Factors / Q000276:immunology*; D006801:Humans; D020381:Interleukin-17 / Q000276:immunology*; D008180:Lupus Erythematosus, Systemic / Q000188:drug therapy* / Q000276:immunology; D008297:Male; D008875:Middle Aged; D010758:Phosphorus / Q000097:blood; D011174:Portugal; D014807:Vitamin D / Q000097:blood / Q000627:therapeutic use*
chemical_list: D000974:Antibodies, Antinuclear; D003176:Complement C3; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; C508717:IL17A protein, human; D020381:Interleukin-17; D014807:Vitamin D; D010758:Phosphorus; D002118:Calcium
keywords: FoxP3 T cells; IL-17A T cells; SLE; Vitamin D