التفاصيل البيبلوغرافية
| العنوان: |
Bacterial exotoxins downregulate cathelicidin (hCAP-18/LL-37) and human β-defensin 1 (HBD-1) expression in the intestinal epithelial cells. |
| المؤلفون: |
Chakraborty, Krishnendu, Ghosh, Shubhamoy, Koley, Hemanta, Mukhopadhyay, Asish Kumar, Ramamurthy, Thandavarayan, Saha, Dhira Rani, Mukhopadhyay, Debashis, Roychowdhury, Swasti, Hamabata, Takashi, Takeda, Yoshifumi, Das, Santasabuj |
| المصدر: |
Cellular Microbiology; Dec2008, Vol. 10 Issue 12, p2520-2537, 18p, 1 Chart, 7 Graphs |
| مصطلحات موضوعية: |
PEPTIDE antibiotics, EPITHELIAL cells, TOXINS, PROTEINS, PROTEIN kinases, PATHOGENIC microorganisms |
| مستخلص: |
Cathelicidin (hCAP-18/LL-37) and β-defensin 1 (HBD-1) are human antimicrobial peptides (AMPs) with high basal expression levels, which form the first line of host defence against infections over the epithelial surfaces. The antimicrobial functions owe to their direct microbicidal effects as well as the immunomodulatory role. Pathogenic microorganisms have developed multiple modalities including transcriptional repression to combat this arm of the host immune response. The precise mechanisms and the pathogen-derived molecules responsible for transcriptional downregulation remain unknown. Here, we have shown that enteric pathogens suppress LL-37 and HBD-1 expression in the intestinal epithelial cells (IECs) with Vibrio cholerae and enterotoxigenic Escherichia coli (ETEC) exerting the most dramatic effects. Cholera toxin (CT) and labile toxin (LT), the major virulence proteins of V. cholerae and ETEC, respectively, are predominantly responsible for these effects, both in vitro and in vivo. CT transcriptionally downregulates the AMPs by activating several intracellular signalling pathways involving protein kinase A (PKA), ERK MAPKinase and Cox-2 downstream of cAMP accumulation and inducible cAMP early repressor (ICER) may mediate this role of CT, at least in part. This is the first report to show transcriptional repression of the AMPs through the activation of cellular signal transduction pathways by well-known virulence proteins of pathogenic microorganisms. [ABSTRACT FROM AUTHOR] |
|
Copyright of Cellular Microbiology is the property of Hindawi Limited and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) |
| قاعدة البيانات: |
Complementary Index |
Full Text Finder