Sharma Kaushik, Bisht Kanchan, Eyo Ukpong B
Center for Brain Immunology and Glia, University of Virginia, Charlottesville, VA, United States.
Department of Neuroscience, University of Virginia, Charlottesville, VA, United States.
Front Cell Dev Biol. 2021 Apr 1;9:652748. doi: 10.3389/fcell.2021.652748. eCollection 2021.
Microglia are unique brain-resident, myeloid cells. They have received growing interest for their implication in an increasing number of neurodevelopmental, acute injury, and neurodegenerative disorders of the central nervous system (CNS). Fate-mapping studies establish microglial ontogeny from the periphery during development, while recent transcriptomic studies highlight microglial identity as distinct from other CNS cells and peripheral myeloid cells. This evidence for a unique microglial ontogeny and identity raises questions regarding their identity and functions across species. This review will examine the available evidence for microglia in invertebrate and vertebrate species to clarify similarities and differences in microglial identity, ontogeny, and physiology across species. This discussion highlights conserved and divergent microglial properties through evolution. Finally, we suggest several interesting research directions from an evolutionary perspective to adequately understand the significance of microglia emergence. A proper appreciation of microglia from this perspective could inform the development of specific therapies geared at targeting microglia in various pathologies.
小胶质细胞是一类独特的驻留在大脑中的髓样细胞。它们在越来越多的中枢神经系统（CNS）神经发育、急性损伤和神经退行性疾病中所起的作用，已引发了越来越多的关注。命运图谱研究确定了发育过程中小胶质细胞起源于外周，而最近的转录组学研究则突出了小胶质细胞与其他中枢神经系统细胞和外周髓样细胞不同的特性。这种关于小胶质细胞独特起源和特性的证据，引发了关于它们在不同物种间的特性和功能的问题。这篇综述将审视有关无脊椎动物和脊椎动物中小胶质细胞的现有证据，以阐明不同物种间小胶质细胞特性、起源和生理学方面的异同。本讨论突出了小胶质细胞在进化过程中的保守和不同特性。最后，我们从进化角度提出了几个有趣的研究方向，以充分理解小胶质细胞出现的意义。从这个角度正确认识小胶质细胞，可为针对各种病理状况中靶向小胶质细胞的特定疗法的开发提供信息。
