Circulating L-selectin levels and endothelial CD34 expression in inflammatory bowel disease.
OBJECTIVE
Soluble L-selectin (sL-selectin) concentrations are positively correlated with disease activity in ulcerative colitis (UC) but not in Crohn's disease (CD). This difference in sL-selectin regulation could be due to a disease specific regulation of L-selectin ligands. The aim of this study was to compare levels of circulating sL-selectin, expression of the L-selectin ligand CD34 in the affected colon, and inflammatory bowel disease activity.


METHODS
Twenty-three patients with UC, 16 patients with CD, and 18 control subjects were included in the study. In blood samples concentrations of serum sL-selectin were determined by an ELISA technique. In colonoscopically obtained biopsies, CD34 expression was evaluated by immunohistochemical methods using monoclonal CD34 antibodies. Disease activity was determined by a clinical semiquantitative scale.


RESULTS
sL-selectin levels were found to be significantly increased along with increasing disease activity in UC (p < 0.001) but not in CD (p > 0.05) patients. UC patients with quiescent and severe disease activity had significantly lower (p < 0.005) and higher (p < 0.002) sL-selectin concentrations than controls, respectively. CD34 expression was found to be increased in both disease groups as compared with controls (p < 0.05).


CONCLUSIONS
A disease-specific regulation of CD34 was not found as an explanation for the distinction in sL-selectin regulation. In the light of recent reports on low sL-selectin in other diseases, it is suggested instead that ongoing neutrophil activation may be the reason for low sL-selectin concentrations during quiescent disease stages, whereas chemokine secretion could explain the increased levels of sL-selectin associated with severe disease activity.
Department of Internal Medicine CF, Glostrup Hospital, University of Copenhagen, Denmark.
J B
JB
Seidelin
B
B
Vainer
T
T
Horn
O H
OH
Nielsen
D000328:Adult; D018952:Antigens, CD34 / Q000032:analysis*; D001706:Biopsy; D016022:Case-Control Studies; D003093:Colitis, Ulcerative / Q000175:diagnosis / Q000378:metabolism*; D003106:Colon / Q000737:chemistry / Q000473:pathology; D003424:Crohn Disease / Q000175:diagnosis / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D019041:L-Selectin / Q000097:blood*; D008297:Male
D018952:Antigens, CD34; D019041:L-Selectin