Distinct Toll-like receptor expression in monocytes and T cells in chronic HCV infection.
OBJECTIVE
Hepatitis C virus often establishes chronic infections. Recent studies suggest that viral and bacterial infections are more common in HCV-infected patients compared to controls. Pathogens are recognized by Toll-like receptors (TLRs) to shape adaptive and innate immune responses.


METHODS
In this study, to assess the ability of HCV-infected host to recognize invading pathogens, we investigated Toll-like receptor expression in innate (monocytes) and adaptive (T cells) immune cells by real-time PCR.


RESULTS
We determined that RNA levels for TLRs 2, 6. 7, 8, 9 and 10 mRNA levels were upregulated in both monocytes and T cells in HCV-infected patients compared to controls. TLR4 was only upregulated in T lymphocytes, while TLR5 was selectively increased in monocytes of HCV-infected patients. MD-2, a TLR4 co-receptor, was increased in patients' monocytes and T cells while CD14 and MyD88 were increased only in monocytes.


CONCLUSIONS
Our data reveal novel details on TLR expression that likely relates to innate recognition of pathogens and immune defense in HCV-infected individuals.
Dolganiuc
Angela
A
University of Massachusetts Medical School, Department of Medicine, 364 Plantation Street, Worcester, MA 01605-2324, United States.
Garcia
Catherine
C
Kodys
Karen
K
Szabo
Gyongyi
G
D000328:Adult; D016022:Case-Control Studies; D005260:Female; D019698:Hepatitis C, Chronic / Q000097:blood / Q000235:genetics / Q000276:immunology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000276:immunology*; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013601:T-Lymphocytes / Q000276:immunology*; D051193:Toll-Like Receptors / Q000032:analysis* / Q000235:genetics*; D015854:Up-Regulation
D012333:RNA, Messenger; D051193:Toll-Like Receptors