Elevated number of recently activated T cells in bone marrow of patients with rheumatoid arthritis: a role for interleukin 15?
Ann Rheum Dis
; 70(1): 227-33, 2011 Jan.
Article
em En
| MEDLINE
| ID: mdl-20980284
ABSTRACT
OBJECTIVES:
(1) To compare the absolute T-cell numbers in bone marrow (BM) isolated from patients with rheumatoid arthritis (RA) and osteoarthritis (OA); (2) to measure the levels of soluble interleukin 15 (IL-15) and IL-7; (3) to analyse the expression of activation markers on T cells; (4) to analyse influence of IL-15 stimulation on T-cell proliferation.METHODS:
BM samples were obtained from patients undergoing joint replacement surgery. Concentrations of IL-15 and IL-7 were measured using specific ELISAs. The absolute number of T lymphocytes, their activation status and proliferation were evaluated by flow cytometry.RESULTS:
BM from patients with RA contained double the number of CD3 T cells in comparison with OA (6.1 vs 2.7 × 10(6) cells/ml, p<0.008). Ratio CD3CD4CD3CD8 was increased in RA BM, clearly indicating accumulation of CD3CD4 cells. T cells obtained from patients with RA expressed higher level of early activation markers than from OA. Elevated levels of IL-15 were found in BM plasma from patients with RA in comparison with patients with OA (1304.5±956.3 pg/ml and 760±238.7 pg/ml respectively, p<0.01). These data were confirmed by immunohistochemistry of RA BM from regions proximal and distal to the joint. Although both CD3CD4 and CD3CD8 cells proliferated after IL-15 stimulation in vitro, CD3CD4 cells from patients with RA proliferated more vigorously than those from patients with OA, reflecting the composition of T-cell subsets in BM.CONCLUSION:
These results suggest that locally overproduced IL-15 may be responsible for the activation and proliferation of T cells in situ, reflected by significantly increased number of activated T cells in RA BM, possibly contributing to the pathogenesis of RA.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Artrite Reumatoide
/
Medula Óssea
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Subpopulações de Linfócitos T
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Interleucina-15
Tipo de estudo:
Observational_studies
Limite:
Adult
/
Aged
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Female
/
Humans
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Male
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Middle aged
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article