ABSTRACT
OBJECTIVE@#To investigate the distribution of pulmonary surfactant protein A (SP-A) like molecules and the bridge of frontier host defense and adaptive immune response cell of CD68 positive macrophages in inflammatory bowel disease (IBD).@*METHODS@#Surgical specimens derived from involved areas and normal area of the colon with Crohn disease (CD) and ulcerative colitis (UC) were obtained from Department of Pathology, Rhode Island Hospital, Brown University Medical Center. The distribution of SP-A like molecule in intestine of IBD was detected by immunohistochemistry.@*RESULTS@#SP-A like molecule located in epithelia of intestine, the surface of intestine villi, blood vessels of connective tissue, and some inflammatory cells. The number of macrophages with both SP-A like molecule and CD68 positive was dramatically increased in the inflammatory area than the normal area. Some CD68 positive macrophages expressed SP-A like immunoreactivity by immunofluorescence double labeling.@*CONCLUSION@#SP-A is an important host defense molecule in lung, and SP-A expression in large intestine may reflect a close relation between 2 organs in immune response towards inflammation.