Joint injury can cause posttraumatic inflammation, which if severe enough can lead to posttraumatic osteoarthritis (PTOA), a progressive and debilitating condition. Posttraumatic inflammation is characterized by an influx of T lymphocytes and upregulation of inflammatory cytokines and degradative enzymes by activated chondrocytes and synoviocytes. Intra-articular bone marrow-derived mesenchymal stem cell (BM-MSC) injection for the treatment of osteoarthritis (OA) has been of interest due to the immunomodulatory properties of these cells. Interleukin (IL)-10, a potent immunomodulatory cytokine, has also been investigated as an OA therapeutic. Therefore, the objective of this study was to evaluate the combinatorial effects of BM-MSCs and IL-10 in OA using a gene therapy approach. We hypothesized that BM-MSCs overexpressing IL-10 would have superior immunomodulatory effects leading to increased suppression of T cell proliferation and decreased production of proinflammatory cytokines, providing protection of the extracellular matrix (ECM) in a stimulated, co-culture OA model. Treatment groups included the following: untransduced BM-MSC, adeno-associated virus (AAV)-IL10-transduced BM-MSC, and AAV-null transduced BM-MSC, which were unstimulated or stimulated with IL-1β/tumor necrosis factor-α (TNF-α). T cell proliferation was significantly decreased by the presence of BM-MSCs, especially when these BM-MSCs were AAV transduced. There was no significant difference in T cell suppression when cells were cultured with AAV-IL10-transduced or AAV-null transduced BM-MSCs. AAV transduction itself was associated with decreased synthesis of IL-1β, IL-6, and TNF-α. Expression of IL-1β and MMP13 was downregulated in AAV-transduced BM-MSCs and MMP13 expression was downregulated in cartilage explants co-cultured with AAV-transduced BM-MSCs. Despite mitigation of some proinflammatory cascades, rescue of ECM loss, as determined by glycosaminoglycan quantification and histological evaluation, did not occur in either AAV-IL10-transduced or AAV-null transduced co-cultures. Although IL-10 overexpression may enhance BM-MSC-mediated T cell suppression, we did not observe significant modulation of inflammation-driven cartilage degradation in cultures containing AAV-IL10-transduced BM-MSCs. AAV transduction itself does appear to affect paracrine signaling by BM-MSCs, which warrants further investigation.

中文翻译：

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腺相关病毒介导的白细胞介素 10 过表达影响马骨髓来源的间充质干细胞的免疫调节特性

关节损伤可导致创伤后炎症，如果足够严重，可导致创伤后骨关节炎 (PTOA)，这是一种进行性和衰弱的疾病。创伤后炎症的特征在于 T 淋巴细胞的流入以及活化的软骨细胞和滑膜细胞对炎症细胞因子和降解酶的上调。由于这些细胞的免疫调节特性，用于治疗骨关节炎 (OA) 的关节内骨髓间充质干细胞 (BM-MSC) 注射引起了人们的兴趣。白细胞介素 (IL)-10 是一种有效的免疫调节细胞因子，也已作为 OA 治疗剂进行了研究。因此，本研究的目的是使用基因治疗方法评估 BM-MSCs 和 IL-10 在 OA 中的组合作用。我们假设过表达 IL-10 的 BM-MSC 将具有出色的免疫调节作用，从而导致 T 细胞增殖的抑制增加和促炎细胞因子的产生减少，从而在受刺激的共培养 OA 模型中提供细胞外基质 (ECM) 的保护。治疗组包括以下：未转导的 BM-MSC、腺相关病毒 (AAV)-IL10 转导的 BM-MSC 和 AAV-null 转导的 BM-MSC，未刺激或用 IL-1β/肿瘤坏死因子-α 刺激(TNF-α)。BM-MSCs 的存在显着降低了 T 细胞增殖，特别是当这些 BM-MSCs 被 AAV 转导时。当细胞与 AAV-IL10 转导或 AAV-null 转导 BM-MSC 一起培养时，T 细胞抑制没有显着差异。AAV 转导本身与 IL-1β、IL-6 和 TNF-α 的合成减少有关。的表达IL-1β和MMP13在 AAV 转导的 BM-MSCs 中下调，MMP13表达在与 AAV 转导的 BM-MSCs 共培养的软骨外植体中下调。尽管减轻了一些促炎级联反应，但在 AAV-IL10 转导或 AAV-null 转导的共培养物中均未发生通过糖胺聚糖定量和组织学评估确定的 ECM 损失的挽救。尽管 IL-10 过表达可能增强 BM-MSC 介导的 T 细胞抑制，但我们没有观察到在含有 AAV-IL10 转导的 BM-MSC 的培养物中炎症驱动的软骨降解的显着调节。AAV 转导本身似乎确实会影响 BM-MSCs 的旁分泌信号传导，这值得进一步研究。