Figure 1

TLR4 mRNA expression is down-regulated in the nasal mucosa of smokers and in severe COPDin vivo. Outpatients attending for upper GI endoscopy or bronchoscopy were recruited for nasal brush sampling. Subjects were excluded on the basis of pre-existing immunosuppression, pulmonary or nasal pathology other than COPD, including current or recent (within 6 weeks) upper or lower respiratory tract infection. Tracheal brush specimens were also collected on a subset of patients undergoing fibreoptic bronchoscopy (n = 9). A. Table showing demographics of the study population. There was no significant difference between the study groups. B. Total RNA from was reverse transcribed into cDNA and used as a template for semi-quantitative PCR reactions using TLR4, TLR2, HBD2 and GAPDH gene-specific primers. (** P < 0.005 vs non-smoking controls; † P < 0.05 vs all controls; $ P < 0.05 vs COPD FEV1 > 1L). C. TLR4 expression by semi-quantitative RTPCR analysis in tracheal and nasal epithelium.