Hügle Thomas, O'Reilly Steven, Simpson Rachel, Kraaij Marina D, Bigley Venetia, Collin Matthew, Krippner-Heidenreich Anja, van Laar Jacob M
Newcastle University, Newcastle upon Tyne, UK.
Arthritis Rheum. 2013 Feb;65(2):481-91. doi: 10.1002/art.37738.
The role of tumor necrosis factor (TNF) in systemic sclerosis (SSc) remains controversial. The present study was undertaken to investigate the influence of TNF receptor (TNFR)-costimulated lymphocytes on collagen expression in fibroblasts.
TNFR expression on mononuclear cells from the dermis and blood of SSc patients was assessed by flow cytometry. Peripheral blood CD3+ lymphocytes were activated with CD3/CD28 beads and costimulated with TNFR-selective variants. Expression of interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), IL-10, and IL-13 was detected by enzyme-linked immunosorbent assay or quantitative reverse transcription-polymerase chain reaction. Healthy fibroblasts were incubated with conditioned media from TNFR-costimulated T lymphocytes, and type I collagen expression was quantified.
TNFRI and TNFRII were up-regulated on dermal T lymphocytes from patients with diffuse cutaneous SSc. TNFRII expression correlated with skin thickening. After CD3/CD28 activation, peripheral blood lymphocytes from SSc patients produced more IL-6, sIL-6R, and IL-13 compared to healthy lymphocytes. Costimulation with TNFRI-selective ligands and soluble TNF further increased IL-6 expression, whereas costimulation with TNFRII led to greater release of sIL-6R. IL-10 expression, which normally occurs after TNFRII costimulation, was impaired in SSc T cells. Supernatants of TNF-costimulated SSc lymphocytes induced higher type I collagen expression in fibroblasts, which was partially reversible by dual inhibition of IL-6 and IL-13. Expression of TNFR and IL-6 in the dermis was reversible in a patient who received lymphoablative therapy prior to autologous hematopoietic stem cell transplantation.
TNF-costimulated T lymphocytes from SSc patients have a propensity to secrete profibrotic cytokines, while the ability to produce IL-10 is weakened. These results suggest that T lymphocytes in SSc support fibrosis, but might lack the capacity to resolve inflammation.
肿瘤坏死因子（TNF）在系统性硬化症（SSc）中的作用仍存在争议。本研究旨在探讨TNF受体（TNFR）共刺激淋巴细胞对成纤维细胞中胶原蛋白表达的影响。
通过流式细胞术评估SSc患者真皮和血液中单核细胞上TNFR的表达。用CD3/CD28磁珠激活外周血CD3+淋巴细胞，并用TNFR选择性变体进行共刺激。通过酶联免疫吸附测定或定量逆转录-聚合酶链反应检测白细胞介素-6（IL-6）、可溶性IL-6受体（sIL-6R）、IL-10和IL-13的表达。将健康成纤维细胞与TNFR共刺激的T淋巴细胞的条件培养基一起孵育，并对I型胶原蛋白表达进行定量。
弥漫性皮肤SSc患者真皮T淋巴细胞上的TNFRI和TNFRII上调。TNFRII表达与皮肤增厚相关。与健康淋巴细胞相比，CD3/CD28激活后，SSc患者的外周血淋巴细胞产生更多的IL-6、sIL-6R和IL-13。用TNFRI选择性配体和可溶性TNF进行共刺激进一步增加IL-6表达，而用TNFRII进行共刺激导致sIL-6R释放增加。通常在TNFRII共刺激后出现的IL-10表达在SSc T细胞中受损。TNF共刺激的SSc淋巴细胞的上清液在成纤维细胞中诱导更高的I型胶原蛋白表达，通过双重抑制IL-6和IL-13可部分逆转。在自体造血干细胞移植前接受淋巴细胞清除治疗的患者中，真皮中TNFR和IL-6的表达是可逆的。
SSc患者TNF共刺激的T淋巴细胞倾向于分泌促纤维化细胞因子，而产生IL-10的能力减弱。这些结果表明，SSc中的T淋巴细胞支持纤维化，但可能缺乏解决炎症的能力。
