Analysis of the plasma proteome associated with acute coronary syndrome: does a permanent protein signature exist in the plasma of ACS patients?

Acute coronary syndrome (ACS) is triggered by the occlusion of a coronary artery usually due to the thrombosis caused by an atherosclerotic plaque. The identification of proteins directly involved in the pathophysiological events underlying ACS will enable more precise diagnoses and a more accurate prognosis to be determined. Accordingly, we have performed a longitudinal study of the plasma proteome in ACS patients by 2-DE and DIGE. Plasma samples from patients, healthy controls, and stable coronary artery disease (CAD) patients were immunodepleted of the six most abundant proteins, and they were analyzed in parallel at four different times: 0 (on admission) and after 4, 60, and 180 days. From a total of 1400 spot proteins analyzed, 33 proteins were differentially expressed in ACS patients when compared with control subjects/stable patients. A small group of seven proteins that appear to be altered at admission remain affected for 6 months and also in the stable CAD patients. Interestingly, the maximum number of altered proteins was observed in the stable CAD patients. Some of the proteins identified had been previously associated with ACS whereas others (such as Alpha-1-B-glycoprotein, Hakata antigen, Tetranectin, Tropomyosin 4) constitute novel proteins that are altered in this pathology.

Watermelon profilin: characterization of a major allergen as a model for plant-derived food profilins.

BACKGROUND: Plant profilins have been reported as minor allergens. They are a well-known pan-allergen family responsible for cross-reactivity between plant-derived foods and pollens. Watermelon profilin has been reported to be a major allergen in watermelon (Citrullus lanatus).The aim of this study was to characterize recombinant watermelon profilin, confirming its reactivity for diagnostic purposes and the development of immunotherapy. METHODS: Native profilin was purified from watermelon extract by affinity chromatography using poly-L-proline. Recombinant His-tagged profilin was produced in Pichia pastoris yeast using pPICZαA vector and purified by metal chelate affinity chromatography. ELISA and immunoblot were carried out with sera from 17 watermelon-allergic patients. Biological activity was tested by the basophil activation test. RESULTS: Native profilin and recombinant profilin were purified and identified by mass spectrometry. Both show similar IgE reactivity in vitro and are biologically active. CONCLUSIONS: Similarities were found in the IgE-binding patterns and biological activity of recombinant profilin and native profilin. Recombinant profilin may be a powerful tool for specific diagnosis.