Biran Roy, Martin Dave C, Tresco Patrick A
The Keck Center for Tissue Engineering, Department of Bioengineering, College of Engineering, University of Utah, Salt Lake City, Utah 84112, USA.
J Biomed Mater Res A. 2007 Jul;82(1):169-78. doi: 10.1002/jbm.a.31138.
The influence of tethering silicon microelectrode arrays on the cortical brain tissue reaction was compared with that of untethered implants placed in the same location by identical means using immunoflourescent methods and cell type specific markers over indwelling periods of 1-4 weeks. Compared with untethered, freely floating implants, tethered microelectrodes elicited significantly greater reactivity to antibodies against ED1 and GFAP over time. Regardless of implantation method or indwelling time, retrieved microelectrodes contained a layer of attached macrophages identified by positive immunoreactivity against ED1. In the tethered condition and in cases where the tissue surrounding untethered implants had the highest levels of ED1+ and GFAP+ immunoreactivity, the neuronal markers for neurofilament 160 and NeuN were reduced. Although the precise mechanisms are unclear, the present study indicates that simply tethering silicon microelectrode arrays to the skull increases the cortical brain tissue response in the recording zone immediately surrounding the microelectrode array, which signals the importance of identifying this important variable when evaluating the tissue response of different device designs, and suggests that untethered or wireless devices may elicit less of a foreign body response.
使用免疫荧光方法和细胞类型特异性标记物，在1至4周的留置期内，将束缚式硅微电极阵列对皮质脑组织反应的影响与通过相同方式放置在相同位置的非束缚式植入物的影响进行了比较。与非束缚式、自由漂浮的植入物相比，随着时间的推移，束缚式微电极对针对ED1和GFAP的抗体引发了显著更高的反应性。无论植入方法或留置时间如何，回收的微电极都包含一层附着的巨噬细胞，通过对ED1的阳性免疫反应性得以识别。在束缚式情况下以及在非束缚式植入物周围组织具有最高水平的ED1+和GFAP+免疫反应性的情况下，神经丝160和NeuN的神经元标记物减少。尽管确切机制尚不清楚，但本研究表明，简单地将硅微电极阵列束缚在颅骨上会增加微电极阵列周围记录区域的皮质脑组织反应，这表明在评估不同设备设计的组织反应时识别这一重要变量的重要性，并表明非束缚式或无线设备可能引发较少的异物反应。
