We previously demonstrated that octadecylamine-functionalized nanodiamond (ND-ODA) and dexamethasone (Dex)-adsorbed ND-ODA (ND-ODA-Dex) promoted anti-inflammatory and pro-regenerative behavior in human macrophages in vitro. In this study, we performed a pilot study to investigate if these immunomodulatory effects translate when used as a treatment for rheumatoid arthritis in mice. Following local injection in limbs of mice with collagen type II-induced arthritis, microcomputed tomography showed that mice treated with a low dose of ND-ODA and ND-ODA-Dex did not experience bone loss to the levels observed in non-treated arthritic controls. A low dose of ND-ODA and ND-ODA-Dex also reduced macrophage infiltration and expression of pro-inflammatory mediators iNOS and tumor necrosis factor-α compared to the arthritic control, while a high dose of ND-ODA increased expression of these markers. Overall, these results suggest that ND-ODA may be useful as an inherently immunomodulatory platform, and support the need for an in-depth study, especially with respect to the effects of dose.

中文翻译：

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免疫调节纳米金刚石聚集体为基础的类风湿关节炎的治疗平台。

我们以前证明十八烷基胺官能化的纳米金刚石（ND-ODA）和地塞米松（Dex）吸附的ND-ODA（ND-ODA-Dex）促进了体外人类巨噬细胞的抗炎和促再生行为。在这项研究中，我们进行了一项初步研究，以调查这些免疫调节作用在用作小鼠类风湿性关节炎的治疗方法时是否转化。在局部注射II型胶原引起的关节炎的小鼠肢体后，微计算机断层扫描显示，低剂量ND-ODA和ND-ODA-Dex治疗的小鼠的骨质流失没有达到未治疗的关节炎对照组所观察到的水平。与关节炎对照组相比，低剂量的ND-ODA和ND-ODA-Dex还能减少巨噬细胞浸润和促炎性介质iNOS和肿瘤坏死因子-α的表达，而高剂量的ND-ODA可以增加这些标志物的表达。总体而言，这些结果表明，ND-ODA可用作固有的免疫调节平台，并支持进行深入研究的需要，尤其是在剂量影响方面。