Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học 'Respiratory Research cung cấp cho các bạn kiến thức về ngành y đề tài: "Respiratory epithelial cells require Toll-like receptor 4 for induction of Human β-defensin 2 by Lipopolysaccharide. | Respiratory Research BioMed Central Research Open Access Respiratory epithelial cells require Toll-like receptor 4 for induction of Human p-defensin 2 by Lipopolysaccharide Ruth MacRedmond Catherine Greene Clifford C Taggart Noel McElvaney and Shane O Neill Address Department of Respiratory Research Royal College of Surgeons in Ireland Beaumont Hospital Dublin 9 Ireland Email Ruth MacRedmond - rmacredm@ Catherine Greene - CMGreene@ Clifford C Taggart - ctaggart@ Noel McElvaney- gmcelvaney@ Shane O Neill - shaneoneill@ Corresponding author Published 12 October 2005 Received 27 April 2005 Respiratory Research 2005 6 116 doi 1465-9921-6-116 Accepted 12 October 2005 This article is available from http content 6 1 1 16 2005 MacRedmond et al licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License http licenses by which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. Abstract Background The respiratory epithelium is a major portal of entry for pathogens and employs innate defense mechanisms to prevent colonization and infection. Induced expression of human P-defensin 2 HBD2 represents a direct response by the epithelium to potential infection. Here we provide evidence for the critical role of Toll-like receptor 4 TLR4 in lipopolysaccharide LPS -induced HBD2 expression by human A549 epithelial cells. Methods Using RTPCR fluorescence microscopy ELISA and luciferase reporter gene assays we quantified interleukin-8 TLR4 and HBD2 expression in unstimulated or agonist-treated A549 and or HEK293 cells. We also assessed the effect of over expressing wild type and or mutant TLR4 MyD88 and or Mal transgenes on LPS-induced HBD2 expression in these cells. Results We demonstrate that A549 cells express TLR4 on their surface and respond directly to .
