CRTH2, an orphan receptor of T-helper-2-cells, is expressed on basophils and eosinophils and responds to mast cell-derived factor(s).
A shift from Th1to Th2-type cell immune response has been suggested to occur during sepsis, contributing to cell-mediated immunity suppression and to poor prognosis. The aim was to study the relationship between old and new Th2 markers and the clinical outcome of sepsis. 30 critically ill patients with sepsis for 48 hours were enrolled in a prospective clinical study. Blood samples were collected at the enrolment, at the 5 th and 10 th day. Serum levels of total IgE and soluble chemokines related to Th1and Th2 responses were evaluated. The percentages and absolute number of CD4+ and CD8+Tcells as well as CRTH2+Tcell subsets were detected by flow cytometry. Sepsis severity was assessed with SOFA score. The mean values of total IgE in septic patients were significantly higher than in controls(p<0.01). Moreover, IgE levels of septic patients who died were higher than those of survived patients(p<0.05). It has been found that IgE levels directly and RANTES inversely correlated with SOFA score at different time points(p<0.01). A significant correlation between the percentages of CRTH2+/CD4+(but not CRTH2+/CD8+)T cells and SOFA at different time points was observed(p<0.05). The direct correlation between total IgE, the percentages of circulating CRTh2+CD4+T cells and the clinical outcome suggests that clinical worsening of sepsis is closely linked to the shift towards a predominant less protective Th2 phenotype. Although these are preliminary results, the longitudinal analysis of these parameters during the disease could be proposed as useful prognostic tools in sepsis.