title: Plasmacytoid Dendritic Cells Producing Interferon-α (IFN-α) and Inducing Mx1 Play an Important Role for CD4(+) Cells and CD8(+) Cells in Necrotizing Lymphadenitis.
abstract: We confirmed the characteristic clinical features of necrotizing lymphadenitis (NEL) in 66 cases (23 male, 43 female) in Japan, which included high fever (38-40°), painful cervical lymphadenopathy (62/66, 93.9%), and leukopenia (under 4,000/mm(3)) (25/53, 47.2%), without seasonal occurrence, in a clinicopathological, immunohistochemical, electron microscopic serological study. Patient age varied from 3-55 years, and 72.7% (44/66) of patients were younger than 30 years. Histopathology of NEL was characterized by the presence of CD8(+) immunoblasts, CD123(+) cells (plasmacytoid dendritic cells; PDCs), histiocytes and macrophages phagocytizing CD4(+) apoptotic lymphocytes, but no granulocytes or bacteria. The number of PDCs and CD8(+) cells in lesions tended to increase with time, and PDCs tended to be larger and irregular in the lesions compared with the non-lesion tissue of the lymph nodes. In addition, PDCs showed no temporal morphological change in the lymph nodes. The number of CD4(+) cells in the lymph node lesions sharply decreased from the 2nd to the 4th week, and then tended to increase; however, CD4(+) cells gradually decreased with time in non-lesion tissue. PDCs may produce interferon-α (IFN-α), which induces Mx1 expression. Strong Mx1 immunoreactivity is indicative of IFN-α production. IFN-α induces transformation of CD8(+) cells into immunoblasts, as well as phagocytosis of apoptotic cells derived from CD4(+) cells by macrophages. Thus, PDCs may play an important role with immune cells, including CD8(+) and CD4(+) cells, in necrotizing lymphadenitis.
authors.affiliation: Department of Dentistry and Oral Surgery, Iwaki　Kyoritsu General Hospital.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Sato
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Asano
authors.forename: Kikuo
authors.initials: K
authors.lastname: Mori
authors.forename: Kazuki
authors.initials: K
authors.lastname: Yamazaki
authors.forename: Haruki
authors.initials: H
authors.lastname: Wakasa
mesh_terms: D000328:Adult; D015415:Biomarkers; D016516:CD4-CD8 Ratio; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D005260:Female; D020042:Histiocytic Necrotizing Lymphadenitis / Q000175:diagnosis / Q000276:immunology* / Q000378:metabolism*; D006801:Humans; D016898:Interferon-alpha / Q000096:biosynthesis*; D008198:Lymph Nodes / Q000276:immunology / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D064547:Myxovirus Resistance Proteins / Q000378:metabolism*; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism*; D014057:Tomography, X-Ray Computed; D055815:Young Adult
chemical_list: D015415:Biomarkers; D016898:Interferon-alpha; C579071:MX1 protein, human; D064547:Myxovirus Resistance Proteins