title: Lymphocyte activation in vivo in the intestinal mucosa of patients with Crohn's disease.
abstract: We analyzed lymphocyte activation state in vivo in lamina propria by applying a panel of monoclonal antibodies for cellular activation markers and by identifying different subsets of 3H-thymidine incorporating lymphoblasts by combining autoradiography with immunoperoxidase staining. In focal lymphoblastoid infiltrates 75 +/- 8% of all inflammatory cells displayed Ia, but lymphoid cells expressing 4F2 (40 +/- 6%) and T9 (14 +/- 3%) activation markers were less frequent. The expression of receptors for interleukin-2 (Tac) was particularly low (4 +/- 1%). There were very few 3H-thymidine incorporating cells (labeling index approx. 1%) and most of them belonged to the T cell series. T4+ blasts outnumbered T8+ blasts, and in this numerically minor subpopulation the activated T4/T8 ratio was 2.9 +/- 0.7. Our results suggest that, although a big part of the local inflammatory lymphocytes in Crohn's disease may be activated according to the expression of Ia and 4F2 activation markers, only a fraction of them possess interleukin-2 receptor and have been pushed to the S-phase of the cell cycle.
authors.forename: Y T
authors.initials: YT
authors.lastname: Konttinen
authors.forename: V
authors.initials: V
authors.lastname: Bergroth
authors.forename: D
authors.initials: D
authors.lastname: Nordström
authors.forename: M
authors.initials: M
authors.lastname: Segerberg-Konttinen
authors.forename: K
authors.initials: K
authors.lastname: Seppälä
authors.forename: M
authors.initials: M
authors.lastname: Salaspuro
mesh_terms: D000328:Adult; D000911:Antibodies, Monoclonal; D001345:Autoradiography; D003424:Crohn Disease / Q000276:immunology*; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D007124:Immunoenzyme Techniques; D007413:Intestinal Mucosa / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D010641:Phenotype; D013601:T-Lymphocytes / Q000145:classification / Q000276:immunology*
chemical_list: D000911:Antibodies, Monoclonal