Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
Department of Orthopaedics, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan.
Ultrasonics. 2014 Mar;54(3):874-81. doi: 10.1016/j.ultras.2013.10.021. Epub 2013 Nov 11.
The goal of this feasibility study was to examine whether sonoporation assisted transduction of siRNA could be used to ameliorate arthritis locally. If successful, such approach could provide an alternative treatment for the patients that have or gradually develop adverse response to chemical drugs. Tumor necrosis factor alpha (TNF-α) produced by synovial fibroblasts has an important role in the pathology of rheumatoid arthritis, inducing inflammation and bone destruction. In this study, we injected a mixture of microbubbles and siRNA targeting TNF-α (siTNF) into the articular joints of rats, and transduced siTNF into synovial tissue by exposure to a collimated ultrasound beam, applied through a probe 6mm in diameter with an input frequency of 3.0 MHz, an output intensity of 2.0 W/cm(2) (spatial average temporary peak; SATP), a pulse duty ratio of 50%, and a duration of 1 min. Sonoporation increased skin temperature from 26.8 °C to 27.3 °C, but there were no adverse effect such as burns. The mean level of TNF-α expression in siTNF-treated knee joints was 55% of those in controls. Delivery of siTNF into the knee joints every 3 days (i.e., 7, 10, 13, and 16 days after immunization) by in vivo sonoporation significantly reduced paw swelling on days 20-23 after immunization. Radiographic scores in the siTNF group were 56% of those in the CIA group and 61% of those in the siNeg group. Histological examination showed that the number of TNF-α positive cells was significantly lower in areas of pannus invasion into the ankle joints of siTNF- than of siNeg-treated rats. These results indicate that transduction of siTNF into articular synovium using sonoporation may be an effective local therapy for arthritis.
本可行性研究的目的是探讨声孔法辅助 siRNA 转导是否可用于局部改善关节炎。如果成功，这种方法可以为那些对化学药物有或逐渐产生不良反应的患者提供一种替代治疗方法。滑膜成纤维细胞产生的肿瘤坏死因子-α（TNF-α）在类风湿关节炎的病理中具有重要作用，可诱导炎症和骨破坏。在这项研究中，我们将微泡和针对 TNF-α 的 siRNA（siTNF）混合物注入大鼠关节，并通过将聚焦超声束透射到滑膜组织来转导 siTNF，应用直径为 6mm 的探头，输入频率为 3.0MHz，输出强度为 2.0W/cm²（空间平均瞬时峰值；SATP），脉冲占空比为 50%，持续时间为 1 分钟。声孔法使皮肤温度从 26.8°C 升高到 27.3°C，但没有出现如灼伤等不良反应。siTNF 处理的膝关节中 TNF-α 表达的平均水平为对照组的 55%。通过体内声孔法每 3 天（即在免疫后 7、10、13 和 16 天）将 siTNF 递送到膝关节中，可显著降低免疫后第 20-23 天的爪肿胀。siTNF 组的放射学评分分别为 CIA 组的 56%和 siNeg 组的 61%。组织学检查显示，在滑膜侵袭踝关节的区域中，siTNF 处理的大鼠 TNF-α 阳性细胞的数量明显低于 siNeg 处理的大鼠。这些结果表明，声孔法介导的 siTNF 转导到关节滑膜可能是关节炎的一种有效局部治疗方法。
