Comparable functions of plasmacytoid and monocyte-derived dendritic cells in chronic hepatitis C patients and healthy donors.
OBJECTIVE
Dendritic cells (DCs) play a key role in immune responses through antigen presentation and cytokine secretion. Hepatitis C virus (HCV) is able to escape elimination by the immune system and often establishes a chronic infection. To investigate whether DC dysfunction is involved in this process, we have studied monoycte-derived DCs (Mo-DCs) and plasmacytoid DCs (pDCs), which produce large amounts of IFN-alpha, from chronic HCV patients and healthy donors.


METHODS
We have assessed TNF-alpha and IFN-alpha production by pDCs using intracellular staining after total PBMCs stimulation with unmethylated CG dinucleotides (CpGs). The induction of allogeneic T cell proliferation by immature Mo-DCs was measured using the MLR assay. The up-regulation of maturation markers and the production of TNF-alpha in response to LPS were analyzed using flow cytometry and ELISA, respectively.


RESULTS
We have detected comparable frequencies of pDCs producing TNF-alpha and IFN-alpha in both chronic HCV patients and healthy donors and we have found that immature Mo-DCs from both patients and donors similarly induce allogeneic T cell proliferation and mature and secrete TNF-alpha in response to LPS.


CONCLUSIONS
Our results demonstrate that both pDC and Mo-DCs are not impaired in HCV infected patients.
Piccioli
Diego
D
Immunology and Virology Department, Chiron Vaccines Research Center, via Fiorentina 1, 53100 Siena, Italy.
Tavarini
Simona
S
Nuti
Sandra
S
Colombatto
Piero
P
Brunetto
Maurizia
M
Bonino
Ferruccio
F
Ciccorossi
Pietro
P
Zorat
Francesca
F
Pozzato
Gabriele
G
Comar
Consuelo
C
Abrignani
Sergio
S
Wack
Andreas
A
D000328:Adult; D000368:Aged; D001782:Blood Donors; D003713:Dendritic Cells / Q000502:physiology*; D005260:Female; D019698:Hepatitis C, Chronic / Q000276:immunology*; D006801:Humans; D016898:Interferon-alpha / Q000096:biosynthesis; D007959:Lymphocyte Culture Test, Mixed; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000166:cytology; D010950:Plasma Cells / Q000166:cytology; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
D016898:Interferon-alpha; D014409:Tumor Necrosis Factor-alpha