Figure 1

Citrullinated proteins are found in all lung tissue lysates. (A) A representative immunoblot with the AMC antibody of proteins (20 μg/lane) from lung tissue lysates of four never smokers and six COPD smokers. (B) One lung sample from each patient group was selected and run on a single-welled SDS-PAGE gel. Each blot was cut into four strips that were used to determine presence of specific proteins (fibrinogen (Fib), citrullinated proteins (AMC), CEP-1 and vimentin (Vim)) with their corresponding antibodies. The immunoblot strips for each lung sample were aligned with the molecular weight markers (kDa). The results shown are three representative blots for a (i) non-smoker, (ii) COPD smoker, (iii) smoker without COPD. (C) The intensity of citrullinated proteins in each lung sample was assessed by blinded semi-quantitative analysis using a 4-point scale (0 to 3) (arbitrary units (AU)). The bar diagrams represent mean ± standard error of the mean (SEM); NS, not statistically significant. AMC, anti-modified citrulline; CEP-1, citrullinated α-enolase peptide 1; COPD, chronic obstructive pulmonary disease; kDa, kiloDaltons.