Division of Experimental Medicine, Imperial College, Hammersmith Hospital, London, United Kingdom.
Int Rev Neurobiol. 2011;101:19-39. doi: 10.1016/B978-0-12-387718-5.00002-X.
Microglia are rapidly activated by a wide range of neuropathological insults. Quantifying microglial density in vivo would allow a new, potentially important range of clinic-pathological correlations. Microglia express the 18kDa translocator protein (TSPO) which can be quantified by the positron emission tomography (PET) ligand [(11)C]PK11195, although signal quantification is limited by nonspecific binding. New generation TSPO radioligands with an improved signal-to-noise ratio are now available, but variation in their binding affinity for the TSPO between subjects complicates their use. This review describes the principles of PET imaging, the rationale and challenges in targeting the TSPO as means of quantifying microglial activation in vivo, and disease applications that have been studied with TSPO-PET hitherto.
小胶质细胞可被多种神经病理学损伤迅速激活。在体内定量检测小胶质细胞密度可提供新的、潜在重要的临床病理相关性。小胶质细胞表达 18kDa 转位蛋白（TSPO），可用正电子发射断层扫描（PET）配体[11C]PK11195 进行定量，尽管信号定量受到非特异性结合的限制。目前已有新一代具有更高信噪比的 TSPO 放射性配体，但由于其在不同个体之间对 TSPO 的结合亲和力存在差异，使得它们的应用变得复杂。本综述描述了 PET 成像的原理、以 TSPO 为靶点作为活体定量检测小胶质细胞激活的原理和挑战，以及迄今为止用 TSPO-PET 研究的疾病应用。
