title: Diminished cytokine signalling against bacterial components in mononuclear leucocytes from ulcerative colitis patients after leukocytapheresis.
abstract: Infiltration by circulating inflammatory cells is a prominent local inflammatory feature of ulcerative colitis (UC). Several trials have suggested that leukocytapheresis by filtration can benefit patients with active UC. We investigated how this therapy might modulate the inflammatory response. Patients with active UC who were beginning repeated filtration leukocytapheresis were studied. Mononuclear cell preparations were obtained from blood before and after the first treatment, and expression of cytokine signalling components and the cell-proliferative response were analysed in vitro. Leukocytapheresis reduced lipopolysaccharide-induced production of proinflammatory cytokines (interleukin-1, -6, -8 and tumour necrosis factor-alpha, P < 0.05 for all) and activation of intracellular signalling components (nuclear factor-kappaB, mitogen-activated protein kinases, and signal transducer and activator of transcription-3), as well as surface expression of toll-like receptor-4 (P < 0.05) in mononuclear cells. The therapy also reduced the cell-proliferative response by mononuclear cells stimulated with sonicated bacterial preparations from autologous intestine (P < 0.05). These results indicate that activated mononuclear cells in the peripheral blood of patients with active UC are removed by leukocytapheresis and replaced by cells with a lower activation status. This replacement may partly explain the therapeutic benefit.
authors.affiliation: Second Department of Medicine, Kurume University School of Medicine, Kurume, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Mitsuyama
authors.forename: A
authors.initials: A
authors.lastname: Suzuki
authors.forename: S
authors.initials: S
authors.lastname: Matsumoto
authors.forename: N
authors.initials: N
authors.lastname: Tomiyasu
authors.forename: K
authors.initials: K
authors.lastname: Takaki
authors.forename: H
authors.initials: H
authors.lastname: Takedatsu
authors.forename: J
authors.initials: J
authors.lastname: Masuda
authors.forename: K
authors.initials: K
authors.lastname: Handa
authors.forename: K
authors.initials: K
authors.lastname: Harada
authors.forename: H
authors.initials: H
authors.lastname: Nishida
authors.forename: A
authors.initials: A
authors.lastname: Toyonaga
authors.forename: M
authors.initials: M
authors.lastname: Sata
mesh_terms: D000328:Adult; D001419:Bacteria / Q000276:immunology*; D001772:Blood Cell Count; D015153:Blotting, Western; D049109:Cell Proliferation; D003093:Colitis, Ulcerative / Q000276:immunology / Q000628:therapy*; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D015870:Gene Expression; D006801:Humans; D007422:Intestines / Q000382:microbiology; D007937:Leukapheresis; D007963:Leukocytes, Mononuclear / Q000276:immunology*; D008070:Lipopolysaccharides / Q000276:immunology; D016131:Lymphocyte Subsets / Q000276:immunology; D008297:Male; D008562:Membrane Glycoproteins / Q000097:blood; D012333:RNA, Messenger / Q000235:genetics; D011956:Receptors, Cell Surface / Q000097:blood; D015398:Signal Transduction / Q000276:immunology; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors
chemical_list: D016207:Cytokines; D008070:Lipopolysaccharides; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C495345:TLR4 protein, human; D051197:Toll-Like Receptor 4; D051193:Toll-Like Receptors