Expanded CD4+CD45RO+ phenotype and defective proliferative response in T lymphocytes from patients with Crohn's disease.
OBJECTIVE
An abnormal immune response may play a pathogenic role in Crohn's disease. The aim of this study was to determine the role of regulatory T cells in Crohn's disease.


METHODS
T-cell phenotype and function were studied in blood lymphocytes from patients with Crohn's disease and a control group consisting of healthy donors and patients with ulcerative colitis.


RESULTS
Flow cytometric studies showed a significant increase in the percentage of CD3+DR+ and CD4+CD45RO+ T cells in patients with Crohn's disease. T cells from patients with Crohn's disease and ulcerative colitis showed a defective proliferative response after stimulation with surface mitogenic ligands (phytohemagglutinin and anti-CD28 or anti-CD3 antibodies). Soluble interleukin-2 receptor alpha was augmented in the Crohn's disease and ulcerative colitis groups. In the Crohn's disease group, impairment of T-lymphocyte proliferation was normalized by exogenous interleukin 2, although endogenous interleukin-2 production and interleukin-2 receptor alpha expression were normal.


CONCLUSIONS
An in vivo expansion of CD4+ T lymphocytes with memory phenotype and impaired T-cell proliferation that can be restored by pharmacological amounts of interleukin 2 was found in patients with Crohn's disease. There is a severe immunodisturbance in the T-cell compartment of patients with either clinically active or inactive Crohn's disease.
Roman
L I
LI
Department of Medicine, Principe de Asturias Hospital, Alcalá University, Madrid, Spain.
Manzano
L
L
De La Hera
A
A
Abreu
L
L
Rossi
I
I
Alvarez-Mon
M
M
D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D003093:Colitis, Ulcerative / Q000276:immunology; D003424:Crohn Disease / Q000276:immunology* / Q000378:metabolism; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D016130:Immunophenotyping; D007376:Interleukin-2 / Q000096:biosynthesis; D017493:Leukocyte Common Antigens / Q000032:analysis*; D016014:Linear Models; D008213:Lymphocyte Activation; D008297:Male; D008875:Middle Aged; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D012995:Solubility
D007376:Interleukin-2; D015375:Receptors, Interleukin-2; D017493:Leukocyte Common Antigens