These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Expression of activation-induced, T cell-derived, and chemokine-related cytokine/lymphotactin and its functional role in rheumatoid arthritis. Author: Blaschke S, Middel P, Dorner BG, Blaschke V, Hummel KM, Kroczek RA, Reich K, Benoehr P, Koziolek M, Müller GA. Journal: Arthritis Rheum; 2003 Jul; 48(7):1858-72. PubMed ID: 12847680. Abstract: OBJECTIVE: To evaluate the possible role of activation-induced, T cell-derived, and chemokine-related cytokine (ATAC)/lymphotactin (Lptn) in the pathogenesis of rheumatoid arthritis (RA). METHODS: ATAC/Lptn levels in serum and synovial fluid samples were measured by sandwich enzyme-linked immunosorbent assay. Expression of messenger RNA for ATAC/Lptn in synovial tissues was analyzed by reverse transcription-polymerase chain reaction (PCR) and by in situ hybridization, and was quantitated by real-time PCR. The phenotype of peripheral blood mononuclear cells (PBMCs) expressing ATAC/Lptn was analyzed by intracellular cytokine staining and flow cytometry. RESULTS: Levels of ATAC/Lptn were similar in sera and synovial fluids from RA patients (n = 20) and osteoarthritis controls (n = 15). In phorbol myristate acetate/ionomycin-stimulated PBMCs, ATAC/Lptn expression was detected in CD8+ T cells and in a significantly increased proportion of CD4+,CD28- T cells from RA patients as compared with healthy controls. In synovial tissues, ATAC/Lptn was predominantly localized in CD3+ T cells in the sublining layer. Lymphocytes, synovial macrophages, and, unexpectedly, fibroblast-like synoviocytes (FLS) were identified as major target cells for ATAC/Lptn in RA synovium, as determined by analysis of the ATAC/Lptn receptor XCR1. In vitro, ATAC/Lptn stimulation of FLS resulted in a marked down-regulation of matrix metalloproteinase 2 production. CONCLUSION: These data indicate that in RA synovium, ATAC/Lptn is mainly produced by T cells. Considering its function as a lymphocyte-specific chemoattractant, ATAC/Lptn might be a key modulator for T cell trafficking in the pathogenesis of RA. In addition, functional studies suggest that ATAC/Lptn may exert additional immunomodulatory effects in RA.[Abstract] [Full Text] [Related] [New Search]