Plasmacytoid dendritic cells accumulate in spleens from chronically HIV-infected patients but barely participate in interferon-alpha expression.
We characterized the localization, phenotype, and some functions of plasmacytoid dendritic cells (pDCs) in the human spleen. pDCs were localized in the marginal zone and the periarteriolar region. Some were also found in the red pulp. pDCs were immature by phenotypic labeling, consistently with their capacity to internalize Dextran in a functional assay. In spleens from HIV-infected patients with thrombocytopenic purpura, these characteristics were unaffected. However, an accumulation of pDCs, but not myeloid dendritic cells (mDCs), was observed in some HIV+ patients, correlating with high proviral loads. Moreover, although undetectable in most HIV- patients, interferon-alpha (IFN-alpha) production was evidenced in situ and by flow cytometry in most HIV+ patients. IFN-alpha was located in the marginal zone. Surprisingly, IFN-alpha colocalized only with few pDCs, but rather with other cells, including T and B lymphocytes, mDCs, and macrophages. Therefore, pDCs accumulated in spleens from HIV+ patients with high proviral loads, but they did not seem to be the main IFN-alpha producers.
Institut Cochin, Université Paris Descartes, Centre National de la Recherche Scientifique (CNRS), Unité Mixte de Recherche (UMR) 8104, Paris, France.
Michelina
M
Nascimbeni
Leïla
L
Perié
Laurent
L
Chorro
Seckou
S
Diocou
Louis
L
Kreitmann
Stéphanie
S
Louis
Laurent
L
Garderet
Bettina
B
Fabiani
Anne
A
Berger
Jürgen
J
Schmitz
Jean-Pierre
JP
Marie
Thierry Jo
TJ
Molina
Jérôme
J
Pacanowski
Jean-Paul
JP
Viard
Eric
E
Oksenhendler
Stéphanie
S
Beq
Orly
O
Abehsira-Amar
Rémi
R
Cheynier
Anne
A
Hosmalin
D023241:Antiretroviral Therapy, Highly Active; D015496:CD4-Positive T-Lymphocytes / Q000187:drug effects / Q000276:immunology / Q000821:virology; D002908:Chronic Disease; D003713:Dendritic Cells / Q000502:physiology*; D004705:Endocytosis; D005434:Flow Cytometry; D005455:Fluorescent Antibody Technique; D015658:HIV Infections / Q000188:drug therapy / Q000276:immunology* / Q000821:virology; D015497:HIV-1 / Q000502:physiology*; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism; D016898:Interferon-alpha / Q000037:antagonists & inhibitors / Q000096:biosynthesis*; D010641:Phenotype; D013154:Spleen / Q000276:immunology*
D018836:Inflammation Mediators; D016898:Interferon-alpha