巨噬细胞是一种免疫细胞,具有多种功能,包括吞噬病原体,抗原呈递和组织重塑。为了履行他们在功能上不同的角色,巨噬细胞经历向一系列表型的极化,特别是经典激活(M1)和交替激活(M2)亚型。然而,二元M1/M2表型未能在体内捕获巨噬细胞亚群的复杂性。因此,采用时空成像技术来可视化巨噬细胞表型和极化是至关重要的,能够监测疾病进展和评估对候选药物的治疗反应。这篇评论首先讨论了起源,巨噬细胞在生理和病理条件下的功能和多样性。随后,我们总结了已鉴定的巨噬细胞表型及其特异性生物标志物.此外,我们提出了通过在体内观察具有特定表型的巨噬细胞来定位病变的成像探针。最后,我们讨论了通过巨噬细胞表型成像监测免疫微环境和疾病进展的挑战和前景.
Macrophage is a kind of immune cell and performs multiple functions including pathogen phagocytosis, antigen presentation and tissue remodeling. To fulfill their functionally distinct roles, macrophages undergo polarization towards a spectrum of phenotypes, particularly the classically activated (M1) and alternatively activated (M2) subtypes. However, the binary M1/M2 phenotype fails to capture the complexity of macrophages subpopulations in vivo. Hence, it is crucial to employ spatiotemporal imaging techniques to visualize macrophage phenotypes and polarization, enabling the monitoring of disease progression and assessment of therapeutic responses to drug candidates. This review begins by discussing the origin, function and diversity of macrophage under physiological and pathological conditions. Subsequently, we summarize the identified macrophage phenotypes and their specific biomarkers. In addition, we present the imaging probes locating the lesions by visualizing macrophages with specific phenotype in vivo. Finally, we discuss the challenges and prospects associated with monitoring immune microenvironment and disease progression through imaging of macrophage phenotypes.