Granulocyte apheresis in inflammatory bowel disease: possible mechanisms of effect.
We have studied the effects of granulocyte apheresis in 18 patients with ulcerative colitis and 6 with Crohn's disease who had failed to respond to conventional therapy. Patients were treated with weekly apheresis using a granulocyte removal column (GI, Otsuka Pharmaceutical Co., Ltd., London, U.K.). We found a mean reduction in circulating granulocytes of 1.29 x 10(9) cells/L with no significant alterations in red blood cell monocyte, total lymphocyte, absolute T-helper, or T-cytotoxic lymphocyte counts. There were no significant changes in complement levels or immunoglobulin subclasses. There was a significant increase in granulocyte adhesion and a reduction in L-selectin expression. The removal of granulocytes is unlikely to explain the effect of granulocytapheresis. The markedly increased expression of alpha(m) integrin/Mac-1 and low L-selectin expression alter the capability of granulocytes to migrate to sites of inflammation and may be responsible for the improvement observed in patients treated with granulocyte apheresis.
Rembacken
B J
BJ
Centre for Digestive Diseases, The General Infirmary, Leeds, United Kingdom.
Newbould
H E
HE
Richards
S J
SJ
Misbah
S A
SA
Dixon
M E
ME
Chalmers
D M
DM
Axon
A T
AT
D000328:Adult; D001781:Blood Component Removal; D015815:Cell Adhesion Molecules / Q000097:blood; D003093:Colitis, Ulcerative / Q000097:blood / Q000628:therapy*; D003424:Crohn Disease / Q000097:blood / Q000628:therapy*; D005260:Female; D006098:Granulocytes; D006801:Humans; D019041:L-Selectin / Q000097:blood; D008297:Male; D011446:Prospective Studies
D015815:Cell Adhesion Molecules; D019041:L-Selectin