Fredericks J Megan, Dash Kiana E, Jaskot Emilia M, Bennett Thomas W, Lerchner Walter, Dold George, Ide David, Cummins Alexander C, Der Minassian Violette H, Turchi Janita N, Richmond Barry J, Eldridge Mark A G
Laboratory of Neuropsychology, NIMH/NIH/DHHS, Bethesda, MD, USA; Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY 10014, USA.
Laboratory of Neuropsychology, NIMH/NIH/DHHS, Bethesda, MD, USA.
J Neurosci Methods. 2020 Jun 1;339:108730. doi: 10.1016/j.jneumeth.2020.108730. Epub 2020 Apr 14.
Modern molecular tools make it possible to manipulate neural activity in a reversible and cell-type specific manner. For rhesus monkey research, molecular tools are generally introduced via viral vectors. New instruments designed specifically for use in monkey research are needed to enhance the efficiency and reliability of vector delivery.
A suite of multi-channel injection devices was developed to permit efficient and uniform vector delivery to cortical regions of the monkey brain. Manganese was co-infused with virus to allow rapid post-surgical confirmation of targeting accuracy using MRI. A needle guide was designed to increase the accuracy of sub-cortical targeting using stereotaxic co-ordinates.
The multi-channel injection devices produced dense, uniform coverage of dorsal surface cortex, ventral surface cortex, and intra-sulcal cortex, respectively. Co-infusion of manganese with the viral vector allowed for immediate verification of injection accuracy. The needle guide improved accuracy of targeting sub-cortical structures by preventing needle deflection.
COMPARISON WITH EXISTING METHOD(S): The current methods, hand-held injections or single slow mechanical injection, for surface cortex transduction do not, in our hands, produce the density and uniformity of coverage provided by the injector arrays and associated infusion protocol.
The efficiency and reliability of vector delivery has been considerably improved by the development of new methods and instruments. This development should facilitate the translation of chemo- and optogenetic studies performed in smaller animals to larger animals such as rhesus monkeys.
现代分子工具使得以可逆且细胞类型特异性的方式操纵神经活动成为可能。对于恒河猴研究，分子工具通常通过病毒载体引入。需要专门为猴研究设计的新仪器来提高载体递送的效率和可靠性。
开发了一套多通道注射装置，以实现向猴脑皮质区域高效且均匀地递送载体。将锰与病毒共同注入，以便术后利用磁共振成像快速确认靶向准确性。设计了一个针引导器，以利用立体定位坐标提高皮质下靶向的准确性。
多通道注射装置分别在背侧皮质表面、腹侧皮质表面和脑沟内皮质产生了密集且均匀的覆盖。将锰与病毒载体共同注入可立即验证注射准确性。针引导器通过防止针头偏转而提高了靶向皮质下结构的准确性。
在我们的操作中，当前用于表面皮质转导的方法，即手持注射或单次缓慢机械注射，无法产生注射阵列及相关输注方案所提供的覆盖密度和均匀性。
新方法和仪器的开发显著提高了载体递送的效率和可靠性。这一进展应有助于将在较小动物中进行的化学遗传学和光遗传学研究转化到诸如恒河猴等较大动物身上。
