Testro AG, Gow PJ, Angus PW, Wongseelashote S, Skinner N, Markovska V, Visvanathan K. Effects of antibiotics on expression and function of Toll-like receptors 2 and 4 on mononuclear cells in patients with advanced cirrhosis.
J Hepatol 2010;
52:199-205. [PMID:
20006396 DOI:
10.1016/j.jhep.2009.11.006]
[Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2009] [Revised: 06/30/2009] [Accepted: 07/02/2009] [Indexed: 12/16/2022]
Abstract
BACKGROUND & AIMS
Toll-like receptors (TLRs) are critical to innate immune responses. TLR4 recognises Gram-negative bacteria, whilst TLR2 recognises Gram-positive. We examined TLR expression and function in cirrhosis, and whether this is affected by antibiotic therapy.
METHODS
Sixty-four subjects were included (23 controls and 41 Child-Pugh C cirrhotic patients). Thirty patients were taking norfloxacin or trimethoprim-sulfamethoxazole as prophylaxis against bacterial peritonitis and 11 were not. In a second study, 8 patients were examined before and after commencement of antibiotics. Monocyte expression of TLR2 and 4 was determined by flow cytometry. Monocytes from the patients with paired samples were stimulated using TLR ligands and TNF-alpha production measured.
RESULTS
Patients not taking antibiotics had significantly decreased TLR4 expression compared with controls (0.74 vs. 1.0, p=0.009) and patients receiving antibiotics (0.74 vs. 0.98, p=0.02). There were no differences with regard to TLR2. In the patients with paired samples, TLR4 expression increased (0.74-1.49, p=0.002) following antibiotic use, whilst again, there was no change in TLR2 expression (0.99 vs. 0.92, p=0.20). TLR4-dependent TNF-alpha production increased following antibiotic use (1077 vs. 3620pg/mL, p<0.05), whilst TLR2-dependent production was unchanged.
CONCLUSIONS
TLR4 expression is decreased in patients with Child-Pugh C cirrhosis, but is restored by antibiotics targeting enteric Gram-negative bacteria. TLR4-dependent cytokine production also increases significantly following antibiotic therapy. This suggests that the high incidence of Gram-negative infection in cirrhotic patients is in part due to down-regulation of the TLR4-dependant immune response and that the efficacy of antibiotic prophylaxis is contributed to by modulation of innate immunity.
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