Healthy Preterm Newborns Show an Increased Frequency of CD4(+)CD25(high)CD127(low)FOXP3(+) Regulatory T Cells with a Naive Phenotype and High Expression of Gut-Homing Receptors

Autor(es)

Renno, C. ; Nadaf, M. I. V. ; Zago, C. A. ; Carneiro-Sampaio, M. ; Palmeira, P.

• Tipo de documento: Artigo Científico
• Fonte: Scandinavian Journal of Immunology; v. 83, n. 6, p. 445-455, JUN 2016.
• Citações Web of Science: 3

Resumo

Treg cells are crucial to prevent immune dysregulation, but little is known about the frequency of these cells in neonates, particularly in very/moderate and late preterm newborns studied as separate groups. The CD4(+)CD25(hi)CD127(lo)FOXP3(+) Treg population was phenotypically characterized to assess maturation markers and gut-homing integrins by flow cytometry in the cord blood of healthy preterm newborns born at 30-33(6/7) gestation weeks (Group 1), at 34-36(6/7) gestation weeks (Group 2) and term newborns born at 37-41 gestation weeks (Group 3), compared to healthy adults. An inverse correlation of the Treg percentage and gestational age was found, with significantly higher frequencies in Group 1 compared to Groups 2 and 3 and in Group 2 compared to Group 3, and significantly higher Treg frequencies and numbers in the neonates compared to the adults. All of the newborns exhibited increased Treg frequencies with a naive phenotype compared to adults. Cytotoxic T-lymphocyte-associated protein 4 CTLA-4 expression in the naive Treg was decreased in both preterm groups compared with those from term newborns and adults, and in the memory Treg from Group 1 compared with the other groups. The frequencies of Treg expressing alpha 4 beta 7 and alpha 4 beta 1 integrins were higher in both preterm groups, but significantly different only in Group 1, when compared with those from the term newborns and the adults. In conclusion, although a high frequency of Treg is present in newborns, an immature phenotype with a higher expression of CD45RA and alpha 4 beta 7/alpha 4 beta 1 and a lower expression of CTLA-4 is found, particularly in the very preterm group. (AU)

• Processo FAPESP: 09/54246-5 - Avaliação da resposta imune neonatal: mecanismos básicos de ativação via receptores semelhantes ao Toll 2 e 4 (TLR-2 e 4) em diferentes células apresentadoras de antígenos de recém-nascidos a termo e pré-termo saudáveis e com sepse precoce e tardia
• Beneficiário: Patricia Palmeira Daenekas Jorge
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 12/10928-8 - Caracterização fenotípica da população de células T reguladoras em sangue de cordão umbilical de recém-nascidos a termo e pré-termo.
• Beneficiário: Camila Rennó Guimarães
• Modalidade de apoio: Bolsas no Brasil - Mestrado