title: Plasmacytoid dendritic cell dynamics and alpha interferon production during Simian immunodeficiency virus infection with a nonpathogenic outcome.
abstract: We addressed the role of plasmacytoid dendritic cells (PDC) in protection against AIDS in nonpathogenic simian immunodeficiency virus (SIVagm) infection in African green monkeys (AGMs). PDC were monitored in blood and lymph nodes (LNs) starting from day 1 postinfection. We observed significant declines in blood during acute infection. However, PDC then returned to normal levels, and chronically infected AGMs showed no decrease of PDC in blood. There was a significant increase of PDC in LNs during acute infection. Blood PDC displayed only weak alpha interferon (IFN-alpha) responses to TLR9 agonist stimulation before infection. However, during acute infection, both blood and LN PDC showed a transiently increased propensity for IFN-alpha production. Bioactive IFN-alpha was detected in plasma concomitant with the peak of viremia, though levels were only low to moderate in some animals. Plasma interleukin 6 (IL-6) and IL-12 were not increased. In conclusion, PDC were recruited to the LNs and displayed increased IFN-alpha production during acute infection. However, increases in IFN-alpha were transient. Together with the lack of inflammatory cytokine responses, these events might play an important role in the low level of T-cell activation which is associated with protection against AIDS in nonpathogenic SIVagm infection.
authors.affiliation: Institut Pasteur, Dakar, Sénégal.
authors.forename: Ousmane M
authors.initials: OM
authors.lastname: Diop
authors.forename: Mickaël J-Y
authors.initials: MJ
authors.lastname: Ploquin
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Mortara
authors.forename: Abdourahmane
authors.initials: A
authors.lastname: Faye
authors.forename: Béatrice
authors.initials: B
authors.lastname: Jacquelin
authors.forename: Désirée
authors.initials: D
authors.lastname: Kunkel
authors.forename: Pierre
authors.initials: P
authors.lastname: Lebon
authors.forename: Cécile
authors.initials: C
authors.lastname: Butor
authors.forename: Anne
authors.initials: A
authors.lastname: Hosmalin
authors.forename: Françoise
authors.initials: F
authors.lastname: Barré-Sinoussi
authors.forename: Michaela C
authors.initials: MC
authors.lastname: Müller-Trutwin
mesh_terms: D000818:Animals; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology; D002452:Cell Count; D002522:Chlorocebus aethiops; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D016898:Interferon-alpha / Q000096:biosynthesis* / Q000276:immunology*; D018664:Interleukin-12 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D008198:Lymph Nodes / Q000166:cytology / Q000276:immunology; D016097:Simian Acquired Immunodeficiency Syndrome / Q000276:immunology* / Q000378:metabolism*; D015302:Simian Immunodeficiency Virus / Q000276:immunology* / Q000472:pathogenicity; D013997:Time Factors
chemical_list: D016898:Interferon-alpha; D015850:Interleukin-6; D018664:Interleukin-12