title: Interleukin-21 mRNA expression during virus infections.
abstract: Interleukin-21 is a cytokine with profound impact on the proliferation and differentiation of activated leukocytes of both the innate and adaptive immune system. In experiments in vitro, antigen activation induces IL-21 production in CD4+ T cells. Where, when, and how the proliferative and activational effects of IL-21 on different leukocytes come into play in vivo in an immune response has so far not been fully investigated. We show here for the first time in vivo, that IL-21 mRNA is produced in the spleen when mice are challenged with herpes simplex virus type 2 (HSV-2) or lymphocytic choriomeningitis virus (LCMV). We show in HSV-2 challenged mice that this production takes place in CD4+ T cell fractions and is absent in CD4+ T cell-depleted fractions. We also show that the peak of IL-21 mRNA production in both the HSV-2 and LCMV-challenged mice coincides with the onset of the adaptive immune response. Thus, our data suggest a role for IL-21 in the early stages of adaptive immune response against virus infections.
authors.affiliation: Institute of Medical Microbiology and Immunology, Bartholin Building, University of Aarhus, 8000 Aarhus C, Denmark. chol@immunology.au.dk
authors.forename: Christian
authors.initials: C
authors.lastname: Holm
authors.forename: Charlotte G
authors.initials: CG
authors.lastname: Nyvold
authors.forename: Søren R
authors.initials: SR
authors.lastname: Paludan
authors.forename: Søren R
authors.initials: SR
authors.lastname: Plaudan
authors.forename: Allan R
authors.initials: AR
authors.lastname: Thomsen
authors.forename: Marianne
authors.initials: M
authors.lastname: Hokland
mesh_terms: D000818:Animals; D001117:Arenaviridae Infections / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D005260:Female; D006558:Herpes Genitalis / Q000276:immunology*; D018258:Herpesvirus 2, Human / Q000276:immunology*; D007371:Interferon-gamma / Q000378:metabolism; D007378:Interleukins / Q000378:metabolism*; D008217:Lymphocytic choriomeningitis virus / Q000276:immunology*; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000378:metabolism; D013154:Spleen / Q000378:metabolism; D013997:Time Factors; D000098546:Interleukin-21
chemical_list: D007378:Interleukins; D012333:RNA, Messenger; D007371:Interferon-gamma; D000098546:Interleukin-21