Mast Cells and Endothelial Cells Mediate Interleukin-33 and ST2 Responses in Distal COPD Lungs

Abstract Rationale Information is missing on the tissue cell expression patterns of interleukin IL-33 (IL-33) and splice variants of the IL-33 receptor ST2 in normal and COPD lungs. Objectives To characterize the expression patterns of IL-33, the soluble ST2 (sST2) and membrane-bound ST2 (ST2L) splice variants in the poorly studied small airway and distal lung compartments in COPD and controls. Methods Surgically excised lung tissue was collected from 38 COPD patients and 21 non-COPD controls. L