Therefore, the eosinophils in the circulation of patients with cGVHD had higher levels of: the adhesion molecules CD11c, CD18, and CD49d; the activation markers CD9 and CD69; the prostaglandin receptor CRTH2 and the formyl peptide receptor-2 (indicated as FPR due to a certain cross-reactivity of the mAb with FPR1) than the eosinophils of transplanted patients who did not have GVHD (Fig. 1B). Here, PTGDR2 is linked to graft versus host disease.