title: Fms-like tyrosine kinase 3 ligand is required for thymic dendritic cell generation from bone marrow-derived CD117⁺ hematopoietic progenitor cells.
abstract: Thymic dendritic cells (TDCs) are a type of dendritic cell (DC) in the thymus, which can enhance the proliferation of thymic T lymphocytes, regulate negative selection and induce central tolerance through autoantigen presentation. However, further investigations using TDCs has been restricted due to insufficient numbers. Therefore, an effective expansion method for TDCs in vitro is urgently required to further examine their biological characteristics. In the present study, a novel system was established using fetal thymus organ culture (FTOC) and a hanging drop culture system in the presence of fms‑like tyrosine kinase 3 ligand (Flt3L), termed the Flt3L/FTOC system. TDCs were successfully generated and expanded from CD117+ bone marrow hematopoietic progenitor cells. Conventional DCs (cDCs; CD11c+B220‑ DCs) and plasmacytoid DCs (pDCs; CD11c+B220+ DCs) were found in the TDCs generated using the Flt3L/FTOC system. These cells exhibited the specific morphological features of DCs, which were confirmed using Giemsa staining. Furthermore, the cytokine and surface marker profiles were also analyzed. Higher expression levels of interferon‑α and interleukin‑12 were observed in the pDCs, compared with the cDCs, and higher expression levels of toll‑like receptor (TLR)7 and TLR9 were found in the pDCs than in the cDCs. In addition, the Flt3L/FTOC‑derived TDCs also exhibited the ability to stimulate the allogenic T cell response. In conclusion, a novel in vitro culture system of thymic cDCs and pDCs using Flt3L was established, and this may provide a methodological basis for understanding the properties of TDCs.
authors.affiliation: Institute of Pediatrics, Children's Hospital Affiliated to Soochow University Suzhou, Jiangsu 215025, P.R. China.
authors.forename: Yunyun
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Stem Cell and Biomedical Material Key Laboratory of Jiangsu Province, State Key Laboratory Incubation Base, Soochow University, Suzhou, Jiangsu 215007, P.R. China.
authors.forename: Dong
authors.initials: D
authors.lastname: Jiang
authors.affiliation: Department of Virology, The Haartman Institute, Molecular Cancer Biology Research Program and Helsinki University Hospital, University of Helsinki, Helsinki FIN‑00100, Finland.
authors.forename: Yizhou
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Institute of Pediatrics, Children's Hospital Affiliated to Soochow University Suzhou, Jiangsu 215025, P.R. China.
authors.forename: Yiping
authors.initials: Y
authors.lastname: Li
authors.affiliation: Stem Cell and Biomedical Material Key Laboratory of Jiangsu Province, State Key Laboratory Incubation Base, Soochow University, Suzhou, Jiangsu 215007, P.R. China.
authors.forename: Xueguang
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Institute of Pediatrics, Children's Hospital Affiliated to Soochow University Suzhou, Jiangsu 215025, P.R. China.
authors.forename: Jian
authors.initials: J
authors.lastname: Wang
authors.affiliation: Department of Medicine, Division of Pulmonary Allergy and Critical Care Medicine, University of Alabama, Birmingham, AL 35233, USA.
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D002454:Cell Differentiation; D002478:Cells, Cultured; D016207:Cytokines / Q000032:analysis / Q000276:immunology; D003713:Dendritic Cells / Q000166:cytology* / Q000276:immunology; D005260:Female; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology; D016898:Interferon-alpha / Q000032:analysis / Q000276:immunology; D018664:Interleukin-12 / Q000032:analysis / Q000276:immunology; D008297:Male; D008565:Membrane Proteins / Q000276:immunology*; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D019009:Proto-Oncogene Proteins c-kit / Q000032:analysis / Q000276:immunology*; D013950:Thymus Gland / Q000166:cytology* / Q000276:immunology
chemical_list: D016207:Cytokines; D016898:Interferon-alpha; D008565:Membrane Proteins; C084881:flt3 ligand protein; D018664:Interleukin-12; D019009:Proto-Oncogene Proteins c-kit