Plasmacytoid dendritic cell dynamics and alpha interferon production during Simian immunodeficiency virus infection with a nonpathogenic outcome.
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.
Diop
Ousmane M
OM
Institut Pasteur, Dakar, Sénégal.
Ploquin
Mickaël J-Y
MJ
Mortara
Lorenzo
L
Faye
Abdourahmane
A
Jacquelin
Béatrice
B
Kunkel
Désirée
D
Lebon
Pierre
P
Butor
Cécile
C
Hosmalin
Anne
A
Barré-Sinoussi
Françoise
F
Müller-Trutwin
Michaela C
MC
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
D016898:Interferon-alpha; D015850:Interleukin-6; D018664:Interleukin-12