Adsorptive depletion of alpha4 integrin(hi)- and CX3CR1hi-expressing proinflammatory monocytes in patients with ulcerative colitis.

BACKGROUND: Two main functionally distinct monocytes phenotypes are known: the CD14(hi)CD16(-) "classical" and the CD14(+)CD16(+) "proinflammatory" phenotypes. The latter phenotype is elevated in patients with ulcerative colitis (UC) and is suspected to have a major role in the immunopathogenesis of UC. AIM: To selectively deplete circulating proinflammatory CD14(+)CD16(+) monocyte phenotype. METHODS: Seven corticosteroid-naïve patients with UC (clinical activity index = 8.7 +/- 1.3) and seven healthy subjects were included. In patients with UC, granulocyte/monocyte adsorption (GMA) was done with an Adacolumn that selectively adsorbs leucocytes of the myeloid lineage. Blood from all subjects at baseline and from the patients immediately after the first GMA session was processed. Isolated monocytes were subjected to fluorescence-activated cell sorter analyses. RESULTS: The seven UC patients achieved remission (CAI