title: Blood levels of CD11b+ memory T lymphocytes are selectively upregulated in patients with active rheumatoid arthritis.
abstract: The adhesion molecules CD11b (a beta2-integrin component) and CD54 (ICAM-1) on blood leukocytes were studied by flow cytometry in patients with rheumatoid arthritis (RA). The fractions of CD4+ cells co-expressing CD11b were elevated in 16 patients with active RA compared with those in 16 RA patients who improved during therapy and 8 healthy controls: 0.8+/-0.12% (mean+/-SEM) versus 0.3+/-0.06% (p<0.002) and 0.3+/-0.06% (p<0.005), respectively. Increased levels of CD11b+CD45R0+ cells were observed in patients with active RA compared to those with improved RA and controls: 12.6+/-3.9% versus 4.8+/-2.7% (p<0.002) and 6.1+/-1.2% (p<0.003), respectively. Disease activity, determined by C-reactive protein, correlated with the numbers of CD11b+CD45R0+ cells: r=0.62 (p<0.001). Seven patients were followed during induction of remission with methotrexate and glucocorticoids. The numbers of CD11b+CD4+ and CD11b+CD45R0+ cells fell significantly after clinical improvement. The levels of CD11b+CD14+ cells (monocytes) did not differ between the groups. The number of CD11b+CD15+ cells (neutrophils) was elevated in patients with RA irrespective of disease activity. The levels of CD54+ cells were not different between the RA and control groups. We conclude that the increased numbers of CD11b+ memory T cells may arise from exposure to stimuli outside the synovial compartment.
authors.affiliation: Institute for Inflammation Research, Rigshospitalet National University Hospital, Copenhagen, Denmark.
authors.forename: H
authors.initials: H
authors.lastname: Nielsen
authors.forename: A A
authors.initials: AA
authors.lastname: Petersen
authors.forename: H
authors.initials: H
authors.lastname: Skjødt
authors.forename: K
authors.initials: K
authors.lastname: Hørslev-Petersen
authors.forename: K
authors.initials: K
authors.lastname: Bendtzen
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D007156:Immunologic Memory; D018799:Intercellular Adhesion Molecule-1 / Q000097:blood; D017493:Leukocyte Common Antigens / Q000097:blood; D016256:Lewis X Antigen / Q000097:blood; D018950:Lipopolysaccharide Receptors / Q000097:blood; D016177:Macrophage-1 Antigen / Q000097:blood*; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000276:immunology; D009504:Neutrophils / Q000276:immunology; D015854:Up-Regulation
chemical_list: D016256:Lewis X Antigen; D018950:Lipopolysaccharide Receptors; D016177:Macrophage-1 Antigen; D018799:Intercellular Adhesion Molecule-1; D017493:Leukocyte Common Antigens