Analyses of exhaled breath condensate cytokines for identification of lung cancer

Early non-invasive detection of lung cancer is a precondition for enabling better prognosis supported by new innovative therapy regimes. The aim of our study was to evaluate angiogenic and inflammatory proteins in exhaled breath condensate (EBC) as markers for lung cancer. Our report presents a diagnostic study of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF) and tumor necrosis factor-α (TNF-α) in EBC of 300 individuals, 84 patients with lung cancer, 111 patients with stable chronic obstructive pulmonary disease (COPD), and in 105 healthy controls. Detection of VEGF and bFGF in EBC was applicable to discriminate cancer patients from COPD patients as well as from healthy volunteers. Especially VEGF seems to be suitable to discriminate between non-small cell lung cancer (NSCLC) patients and control groups with highest VEGF values in EBC of patients with progressive NSCLC. The concentration of angiogenic factors correlated with disease progression as well as higher tumor stage. This study supports cytokine analysis in EBC as a suitable noninvasive diagnostic screening method for lung cancer detection and monitoring

Utilisation of antibody microarrays for the selection of specific and informative antibodies from recombinant library binders of unknown quality

Many diagnostic and therapeutic concepts require antibodies of high specificity. Recombinant binder libraries and related selection approaches allow the efficient isolation of antibodies against almost every target of interest. Nevertheless, it cannot be guaranteed that selected antibodies perform well and interact specifically enough with analytes unless an elaborate characterisation is performed. Here, we present an approach to shorten this process by combining the selection of suitable antibodies with the identification of informative target molecules by means of antibody microarrays, thereby reducing the effort of antibody characterisation by concentrating on relevant molecules. In a pilot scheme, a library of 456 single-chain variable fragment (scFv) binders to 134 antigens was used. They were arranged in a microarray format and incubated with the protein content of clinical tissue samples isolated from pancreatic ductal adenocarcinoma and healthy pancreas, as well as recurrent and non-recurrent bladder tumours. We observed significant variation in the expression of the E3 ubiquitin-protein ligase (CHFR) as well as the glutamate receptor interacting protein 2 (GRIP2), for example, always with more than one of the scFvs binding to these targets. Only the relevant antibodies were then characterised further on antigen microarrays and by surface plasmon resonance experiments so as to select the most specific and highest affinity antibodies. These binders were in turn used to confirm a microarray result by immunohistochemistry analysis