title: Infiltration of CD19+ plasma cells with frequent labeling of Ki-67 in corticosteroid-resistant active ulcerative colitis.
abstract: Abnormalities in humoral immunity are implicated in the pathogenesis of ulcerative colitis. However, the detailed mechanisms of B-cell activation in the locale remain unaccounted for. We analyzed ulcerative colitis from the standpoint of lymphocytic expansion in the loco. Intestinal specimens obtained at surgery from 30 patients with ulcerative colitis treated with corticosteroids and 15 with Crohn's disease were analyzed by immunohistochemistry and flow cytometry. Ulcerative colitis was characterized by a diffuse distribution of Ki-67(+) small round cells particularly in the ulcer base (that were CD19(+) and CD20(-)), with a significant number of them also CD138(+). Immunoelectron microscopy for CD19 revealed an abundance of rough endoplasmic reticulum in the cytoplasm. These indicated that they are of immature plasma lineage cells. By contrast, plasma cells in Crohn's disease were negative for CD19, and the labeling for Ki-67 was infrequent, showing mature phenotype. Flow cytometry revealed an occurrence of CD19(+) and CD20(-) cells in ulcerative colitis but not in Crohn's disease. The labeling index of Ki-67 among CD19(+) plasma cells was positively correlated with the clinical activity of ulcerative colitis. High labeling of Ki-67 in CD19(+) plasma cells is specific for active ulcerative colitis that was resistant to medical treatment by corticosteroids.
authors.affiliation: Department of Gastroenterology, Osaka City University Graduate School of Medicine, Osaka, Japan. jinno@hyo-med.ac.jp
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Jinno
authors.forename: Haruo
authors.initials: H
authors.lastname: Ohtani
authors.forename: Shiro
authors.initials: S
authors.lastname: Nakamura
authors.forename: Motoji
authors.initials: M
authors.lastname: Oki
authors.forename: Kiyoshi
authors.initials: K
authors.lastname: Maeda
authors.forename: Kohei
authors.initials: K
authors.lastname: Fukushima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Nagura
authors.forename: Nobuhide
authors.initials: N
authors.lastname: Oshitani
authors.forename: Takayuki
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Arakawa
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018941:Antigens, CD19 / Q000378:metabolism*; D001402:B-Lymphocytes / Q000378:metabolism / Q000473:pathology; D015415:Biomarkers / Q000378:metabolism; D019070:Cell Lineage; D002648:Child; D003093:Colitis, Ulcerative / Q000188:drug therapy / Q000378:metabolism* / Q000601:surgery; D003424:Crohn Disease / Q000188:drug therapy / Q000378:metabolism / Q000601:surgery; D004351:Drug Resistance; D004721:Endoplasmic Reticulum / Q000378:metabolism / Q000648:ultrastructure; D005260:Female; D005434:Flow Cytometry; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010950:Plasma Cells / Q000473:pathology*
chemical_list: D018941:Antigens, CD19; D015415:Biomarkers; D005938:Glucocorticoids; D019394:Ki-67 Antigen