Poly I:C-induced expression of intercellular adhesion molecule-1 in intestinal epithelial cells

Department of Pathology, Nihon University School of Dentistry, Tokyo, Japan.
Clinical & Experimental Immunology (Impact Factor: 3.04). 04/2009; 156(2):294-302. DOI: 10.1111/j.1365-2249.2009.03892.x
Source: PubMed


Intercellular adhesion molecul-1 (ICAM-1) is a transmembrane glycoprotein belonging to the immunoglobulin superfamily of adhesion molecules and plays perdominant roles in recruitment and trafficking of leucocytes to sites of inflammation. ICAM-1 expression in intestinal epithelial cells (IECs) is enhanced by several stimuli, such as proinflammatory cytokines, bacterial infections or pathogen-associated molecular patterns. One of these stimuli, double-stranded RNA (dsRNA), is a by-product of viral replication and can be recognized by its cognate receptor Toll-like receptor 3 (TLR-3). In spite of expression of both TLR-3 and ICAM-1 in IECs, correlation between TLR-3-signalling and ICAM-1 expression has never been examined in IECs. In the present study, we investigated whether poly I:C, an analogue of dsRNA, can stimulate the expression of ICAM-1 in IEC line, HT-29. Poly I:C-stimulation up-regulated the expression of ICAM-1 mRNA by real-time polymerase chain reaction. Enhanced expression of ICAM-1 was confirmed in protein level by immunofluoresense cell staining and enzyme-linked immunosorbent assay by measuring the released soluble ICAM-1 in culture supernatant. As the stimulation effect was reduced by pre-treatment of the cells with anti-TLR-3 antibody, poly I:C-binding signal was thought to be sensed by TLR-3 on the surface of HT-29. The results of luciferase assay and nuclear factor kappa-b (NF-kappaB) inhibitor treatment experiments indicated that the downstream signal was mainly transduced by transcription factor, NF-kappaB. All these results demonstrated the connection between TLR-3 signalling and ICAM-1 expression in HT-29 cells and indicated the importance of coordinated function of both innate and adaptive immunity against viral infections.

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    PLoS ONE 05/2014; 9(5):e96608. DOI:10.1371/journal.pone.0096608 · 3.23 Impact Factor
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    • "Total RNA was purified using RNeasy mini kit (QIAGEN, Tokyo, Japan). cDNA was synthesized with Superscript III reverse transcriptase (Invitrogen, San Diego, CA) and subjected to RT-PCR as described previously [20]. Real-time PCR was performed using LightCycler nano (Roche, Tokyo, Japan) with SYBR green (TaKaRa, Tokyo, Japan). "
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    PLoS ONE 07/2013; 8(7):e68257. DOI:10.1371/journal.pone.0068257 · 3.23 Impact Factor
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    • "This difference could be linked to the localization of TLR3 in HT-29. Indeed expression patterns described for this cell line suggest localization in both cytoplasm and cell membrane [34], [42], [43], a finding that we confirmed by flow cytometry. In our hands, TLR7, TLR8 and TLR9 agonists did not induce NF-κB activation in HT-29, Caco-2 nor in THP1 reporter cell lines. "
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    PLoS ONE 09/2010; 5(9). DOI:10.1371/journal.pone.0013092 · 3.23 Impact Factor
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