[Human plasmacytoid dendritic cells from patients with chronic hepatitis B induce the generation of CD4+CD25+Treg in vitro].
OBJECTIVE
To compare the ability of plasmacytoid dendritic cells (pDCs) from chronic HBV patients and healthy controls to induce the the generation of CD4+CD25+Treg cells.


METHODS
The pDCs were isolated from PBMCs of 46 chronic HBV patients, 10 resolved HBV patients and 25 healthy controls by magnetic cell sorting. Purified CD4+CD45RA+ naive T cells were incubated with allogeneic pDCs from chronic HBV infected patients, resolved HBV patients or healthy controls. The cells were stimulated with HBcAg or tetanus toxin. The proportion of CD4+CD25+Treg in CD4+ T cells primed by pDCs was determined by flow cytometry, the expression of Fox p3 mRNA was detected by RT-PCR, IL-10 and TGFb1 expression was quantified using ELISA kits.


RESULTS
Compared with pDC isolated from healthy controls and the resolved HBV patients, pDC from chronic HBV patients was more effective in suppression of CD4+ T cells proliferation and interferon production when CD25-depleted PBMCs were stimulated with HBcAg, (7999.36+/-374.74 vs 11 282.56+/-1174.46; 7999.36+/-374.74 vs 12 304.58+/-1462.81, P less than 0.05 ). Depletion of CD4+CD25+ Treg from CD4+ T cells primed by pDC led to the lose of capability to suppress HBV-specific T-cell responses. When CD25- depleted PBMCs were stimulated with purified tetanus toxin, there was no significantly difference in proliferation between CD25-depleted PBMC co-cultured with pDC-primed CD4+ T cells and CD25-depleted PBMC cultured without pDC-primed CD4+ T cells. A higher percentage of CD4+CD25+ Treg was detected within the population of CD4+ T cells primed by pDC from chronic HBV patients compared with healthy controls and resolved HBV patients (5.99%+/-1.85% vs 3.04%+/-0.79%; 5.99%+/-1.85% vs 3.01%+/-1.53%, P less than 0.05). Accordingly, CD25+Treg from pDC-primed CD4+ T cells displayed a higher Fox P3 mRNA level. The IL-10 and TGFb1 could be also detectable in the supernatants of pDC-primed CD4+ T cells.


CONCLUSIONS
pDCs from chronic hepatitis B induce the generation of a higher proportion of CD4+CD25+ Treg compared with pDCs from healthy controls.
Hong
Jun
J
Department of Clinical Laboratory, Renmin Hospital of Wuhan University, Wuhan 430060, China.
Li
Yan
Y
Gong
Zuo-jiong
ZJ
D000328:Adult; D049109:Cell Proliferation; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods; D016207:Cytokines / Q000378:metabolism; D003713:Dendritic Cells / Q000276:immunology* / Q000378:metabolism; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D051858:Forkhead Transcription Factors / Q000378:metabolism; D006512:Hepatitis B Core Antigens / Q000494:pharmacology; D019694:Hepatitis B, Chronic / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000166:cytology / Q000378:metabolism; D050378:T-Lymphocytes, Regulatory / Q000166:cytology / Q000276:immunology* / Q000378:metabolism; D055815:Young Adult
D016207:Cytokines; C418974:FOXP3 protein, human; D051858:Forkhead Transcription Factors; D006512:Hepatitis B Core Antigens