Cytotoxic CD4 T cells in viral hepatitis.
J Viral Hepat
; 13(8): 505-14, 2006 Aug.
Article
in En
| MEDLINE
| ID: mdl-16901280
ABSTRACT
CD4+ T cells are thought to contribute to antiviral immune responses by secretion of cytokines thereby providing help to CD8+ T and B cells. However, perforin-positive cytotoxic CD4+ T cells have been described in human immunodeficiency virus-positive patients suggesting a role not only of CD8+ but also of CD4+ T cells for killing virus-infected cells. We investigated 76 patients with viral hepatitis [15 hepatitis B virus (HBV), 22 HBV/hepatitis D virus and 17 hepatitis C virus (HCV)] for cytotoxic CD4+ T cells. The frequency of perforin-positive CD4+ T cells in viral hepatitis was highly variable ranging from < 1% to more than 25%. Perforin-positive CD4+ T cells displayed the phenotype of terminally differentiated effector cells (CD28-, CD27-). The highest frequencies of CD4+ cytotoxic T lymphocytes (CTLs) were found in patients with delta hepatitis (P = 0.04 vs HBV and HCV patients), and the presence of CD4+ CTLs was associated with elevated aspartate aminotransferase levels (P = 0.01) and decreased platelet counts (P = 0.03). Perforin-positive CD4+ T cells decreased in two individuals during spontaneous clearance of acute hepatitis C. Significant associations were found between the frequency of perforin-expressing CD4+ cells and age (P = 0.04), perforin-positive CD8+ cells (P < 0.001) and perforin-positive CD4-/CD8- lymphoid cells (P = 0.002). Differentiated CD27- effector CD4+ CTLs can be detected in patients with viral hepatitis. In particular in patients with more advanced liver disease, the accumulation of perforin-positive T cells with age could be one correlate for the more severe course of viral hepatitis in elderly individuals.
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Collection:
01-internacional
Database:
MEDLINE
Main subject:
T-Lymphocytes, Cytotoxic
/
CD4-Positive T-Lymphocytes
/
Hepatitis, Viral, Human
/
Hepatitis Viruses
Limits:
Adult
/
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
J Viral Hepat
Journal subject:
GASTROENTEROLOGIA
Year:
2006
Document type:
Article
Affiliation country:
Germany
Publication country:
ENGLAND
/
ESCOCIA
/
GB
/
GREAT BRITAIN
/
INGLATERRA
/
REINO UNIDO
/
SCOTLAND
/
UK
/
UNITED KINGDOM