The nervous system coordinates pathways and circuits to process sensory information and govern motor behaviors. Mapping these pathways is important to further understand the connectivity throughout the nervous system and is vital for developing treatments for neuronal diseases and disorders. We targeted long ascending propriospinal neurons (LAPNs) in the rat spinal cord utilizing Fluoro-Ruby, a traditional chemical tracer, and two dual-viral systems. Dual-viral tracing utilizing a retrograde adeno-associated virus (retroAAV), which confers robust labeling in the brain, resulted in a small number of LAPNs being labeled, but dual-viral tracing using a highly efficient retrograde (HiRet) lentivirus provided robust labeling similar to Fluoro-Ruby. However, dual-viral tracing with HiRet lentivirus improved specificity of labeling beyond that of Fluoro-Ruby. These data demonstrate that dual-viral tracing in the spinal cord employing a HiRet lentivirus provides robust and specific labeling of LAPNs and emphasizes the need to empirically optimize viral systems to target specific neuronal population(s).

中文翻译：

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双病毒转导增强了靶向长脊髓长神经元时标记的数量和特异性

神经系统协调通路和回路以处理感觉信息和控制运动行为。绘制这些通路对于进一步了解整个神经系统的连通性非常重要，对于开发神经元疾病和紊乱的治疗方法也至关重要。我们利用传统化学示踪剂 Fluoro-Ruby 和两个双病毒系统靶向大鼠脊髓中的长上升脊髓神经元 (LAPN)。利用逆行腺相关病毒 (retroAAV) 进行双病毒追踪，在大脑中赋予稳健的标记，导致少量 LAPN 被标记，但使用高效逆行 (HiRet) 慢病毒的双病毒追踪提供了稳健的标记类似于氟红宝石。然而，使用 HiRet 慢病毒的双病毒追踪提高了标记的特异性，超过了 Fluoro-Ruby。这些数据表明，使用 HiRet 慢病毒在脊髓中进行双病毒追踪可提供稳健且特定的 LAPN 标记，并强调需要根据经验优化病毒系统以针对特定神经元群体。