Department of Neuroscience and Regenerative Medicine, Medical College of Georgia, Augusta University, Augusta, GA, USA.
Department of Medical Illustration, Medical College of Georgia, Augusta University, Augusta, GA, USA.
Chem Senses. 2022 Jan 1;47. doi: 10.1093/chemse/bjac024.
Sensory cells that specialize in transducing olfactory and gustatory stimuli are renewed throughout life and can regenerate after injury unlike their counterparts in the mammalian retina and auditory epithelium. This uncommon capacity for regeneration offers an opportunity to understand mechanisms that promote the recovery of sensory function after taste and smell loss. Immune responses appear to influence degeneration and later regeneration of olfactory sensory neurons and taste receptor cells. Here we review surgical, chemical, and inflammatory injury models and evidence that immune responses promote or deter chemosensory cell regeneration. Macrophage and neutrophil responses to chemosensory receptor injury have been the most widely studied without consensus on their net effects on regeneration. We discuss possible technical and biological reasons for the discrepancy, such as the difference between peripheral and central structures, and suggest directions for progress in understanding immune regulation of chemosensory regeneration. Our mechanistic understanding of immune-chemosensory cell interactions must be expanded before therapies can be developed for recovering the sensation of taste and smell after head injury from traumatic nerve damage and infection. Chemosensory loss leads to decreased quality of life, depression, nutritional challenges, and exposure to environmental dangers highlighting the need for further studies in this area.
专门用于转导嗅觉和味觉刺激的感觉细胞在整个生命过程中都在更新，并且可以在受伤后再生，这与哺乳动物视网膜和听觉上皮中的感觉细胞不同。这种不常见的再生能力为了解促进味觉和嗅觉丧失后感觉功能恢复的机制提供了机会。免疫反应似乎会影响嗅觉感觉神经元和味觉受体细胞的变性和随后的再生。在这里，我们回顾了手术、化学和炎症损伤模型以及免疫反应促进或阻碍化学感觉细胞再生的证据。对化学感觉受体损伤的巨噬细胞和中性粒细胞反应是研究最广泛的，但对于它们对再生的净效应还没有共识。我们讨论了差异的可能技术和生物学原因，例如外周和中枢结构之间的差异，并为理解免疫调节化学感觉再生提出了进展方向。在开发治疗头部受伤、创伤性神经损伤和感染导致的味觉和嗅觉丧失的疗法之前，我们必须扩大对免疫-化学感觉细胞相互作用的机制理解。化学感觉丧失会导致生活质量下降、抑郁、营养挑战和暴露于环境危险之中，这突出表明需要在这一领域进行进一步研究。
