Increased intraluminal release of eosinophil granule proteins EPO, ECP, EPX, and cytokines in ulcerative colitis and proctitis in segmental perfusion.
OBJECTIVE
The role of the eosinophil granulocyte in bowel mucosa in inflammatory bowel disease still remains obscure. The present study was performed in order to elucidate the local eosinophil activity and activating cytokines in the inflamed lesions of colon and rectum in patients with ulcerative colitis and proctitis.


METHODS
The activity of intestinal eosinophils with respect to the release of granule proteins was studied in 18 patients (10 with colitis and 8 with isolated proctitis) and 18 healthy controls, using intraluminal segmental perfusion of the sigmoid colon and rectum. The released amounts of eosinophil granule proteins: eosinophil cationic protein (ECP), eosinophil peroxidase (EPO), and eosinophil protein X (EPX) to perfusion fluid were determined by radioimmunoassays. The intraluminal release of possible eosinophil priming cytokines granulocyte/macrophage-colony stimulating factor (GM-CSF) and interleukin 8 (IL-8), were analyzed by immunoassays.


RESULTS
The mucosal release of ECP, EPO, and EPX was increased 10- to 20-fold in patients with colitis and proctitis compared with controls. The intraluminal release of GM-CSF and IL-8, was several-fold enhanced in patients with colitis and proctitis. We also found a correlation between all three eosinophil granule proteins and the levels of IL-8/GM-CSF in the sigmoidal segments of patients with colitis.


CONCLUSIONS
We conclude that the increased release of ECP, EPO, and EPX to colorectal perfusion fluid indicate eosinophil involvement in the local disease in patients with colitis and proctitis. IL-8 and GM-CSF may play a role in eosinophil accumulation and priming in colitis.
Carlson
M
M
Department of Medical Sciences, University of Uppsala, Sweden.
Raab
Y
Y
Peterson
C
C
Hällgren
R
R
Venge
P
P
D000328:Adult; D000368:Aged; D001798:Blood Proteins / Q000378:metabolism*; D003093:Colitis, Ulcerative / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism*; D047091:Eosinophil Granule Proteins; D047209:Eosinophil Peroxidase; D047208:Eosinophil-Derived Neurotoxin; D004804:Eosinophils / Q000378:metabolism*; D005260:Female; D016178:Granulocyte-Macrophage Colony-Stimulating Factor / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000378:metabolism*; D016209:Interleukin-8 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D010544:Peroxidases / Q000378:metabolism; D011349:Proctitis / Q000378:metabolism*; D012260:Ribonucleases
D001798:Blood Proteins; D016207:Cytokines; D047091:Eosinophil Granule Proteins; D018836:Inflammation Mediators; D016209:Interleukin-8; D016178:Granulocyte-Macrophage Colony-Stimulating Factor; D047209:Eosinophil Peroxidase; D010544:Peroxidases; D047208:Eosinophil-Derived Neurotoxin; D012260:Ribonucleases