title: Memory Th-17 cells specific for C. albicans are persistent in human peripheral blood.
abstract: Th-17 cells, a new subset of effector CD4(+) T cells, have been identified in mice and in humans. In the present study, we show that a high level of IL-17 and a high frequency of IL-17-producing cells were detected by ELISA and ELISPOT assay, respectively, when human PBMCs were stimulated with both anti-CD3 and anti-CD28. Further analysis of IL-17-producing cells by flow cytometry showed that CD4(+) T cells were the main contributor to IL-17 production, and IL-17 production could be directly induced by purified CD4(+) T cells at the protein and transcriptional levels. Phenotypic analyses revealed that the majority of IL-17-producing CD4(+) T cells were memory cells with the expression of CD45RO, CD69, CCR6 and CCR4, and approximately 70% of IL-17-producing CD4(+) T cells expressed CCR7. In addition, Th-17 cells were different from Th1, Th2 and Treg cells, because the expression of IL-17, IFN-gamma, IL-4 or Foxp3 was restricted to distinct CD4(+) T subsets. Importantly, stimulation of PBMCs with heated-inactivated Candida albicans (C. albicans) yeast or hyphae induced IL-17 production at the protein and transcriptional levels. These data suggest that memory Th-17 cells are present in healthy individual PBMCs and some memory Th-17 cells might play an important role in the defense against the infections of fungi such as C. albicans.
authors.affiliation: Department of Immunology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou, China.
authors.forename: Maohua
authors.initials: M
authors.lastname: Zhou
authors.forename: Binyan
authors.initials: B
authors.lastname: Yang
authors.forename: Ruihong
authors.initials: R
authors.lastname: Ma
authors.forename: Changyou
authors.initials: C
authors.lastname: Wu
mesh_terms: D000328:Adult; D002176:Candida albicans / Q000276:immunology*; D049109:Cell Proliferation; D005260:Female; D005312:Fetal Blood / Q000276:immunology; D006262:Health; D006801:Humans; D007156:Immunologic Memory / Q000276:immunology*; D020381:Interleukin-17 / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010641:Phenotype; D006377:T-Lymphocytes, Helper-Inducer / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D014158:Transcription, Genetic / Q000235:genetics
chemical_list: D020381:Interleukin-17