Activated T cells enhance interferon- production by plasmacytoid dendritic cells stimulated with RNA-containing immune complexes

作者:Leonard Dag*; Eloranta Maija Leena; Hagberg Niklas; Berggren Olof; Tandre Karolina; Alm Gunnar; Roennblom Lars
来源:Annals of the Rheumatic Diseases, 2016, 75(9): 1728-1734.
DOI:10.1136/annrheumdis-2015-208055

摘要

Objectives Patients with systemic lupus erythematosus (SLE) have an ongoing interferon- (IFN-) production by plasmacytoid dendritic cells (pDCs). We investigated whether T cells can promote IFN- production by pDCs. Methods Human pDCs were stimulated with immune complexes (ICs) containing U1 small nuclear ribonucleic proteins particles and SLE-IgG (RNA-IC) in the presence of T cells or T cell supernatants. T cells were activated by anti-CD3/CD28 antibodies or in a mixed leucocyte reaction. IFN- and other cytokines were determined in culture supernatants or patient sera with immunoassays. The effect of interleukin (IL) 3 and granulocyte-macrophage-colony-stimulating factor (GM-CSF) on pDCs was examined by the use of antibodies, and the expression of CD80/CD86 was determined using flow cytometry. Results Activated T cells and supernatants from activated T cells increased IFN- production by >20-fold. The stimulatory effect of T cell supernatants was reduced after depletion of GM-CSF (81%) or by blocking the GM-CSF receptor (55%-81%). Supernatant from activated T cells, furthermore, increased the frequency of CD80 and CD86 expressing pDCs stimulated with RNA-IC from 6% to 35% (p<0.05) and from 10% to 26% (p<0.01), respectively. Activated SLE T cells enhanced IFN- production to the same extent as T cells from healthy individuals and a subset of patients with SLE had increased serum levels of GM-CSF. Conclusions Activated T cells enhance IFN- production by RNA-IC stimulated pDCs via GM-CSF and induce pDC maturation. Given the increased serum levels of GM-CSF in a subset of patients with SLE, these findings suggest that activated T cells may upregulate type I IFN production in SLE.

  • 出版日期2016-9