Macrophage Imaging of Intracranial Aneurysms

Abstract

Considered with a poor outcome of subarachnoid hemorrhage due to rupture of intracranial aneurysms (IAs), treatment interventions to prevent rupture of the lesions are mandatory for social health. As treatment option is limited to surgical manipulations, like microsurgical clipping, endovascular coiling or deployment of flow diverter, and these surgical interventions have a potential risk of complications in nature, a proper selection of rupture-prone IAs among ones incidentally found is essential. Today, a rupture risk in each case is estimated by several factors like patient characteristics and morphological ones of each lesion. However, unfortunately, an IA without treatment sometimes unexpectedly ruptures resulting in a devastating outcome or an IA surgically treated is turned out to have a thick wall. To achieve more efficient treatment interventions, the development of a novel diagnostic modality is required. Here, mainly through the accumulation of experimental findings, the crucial contribution of macrophagemediated chronic inflammatory responses to IA progression have been revealed, making macrophage being a promising target for a diagnosis. If we could non-invasively visualize accumulation of macrophages in lesions, this imaging technique 'macrophage imaging' may enable a qualitative evaluation of IAs to stratify rupture-prone 'dangerous' lesions among many stable ones. Thereby, a development of macrophage imaging makes an indication of surgical interventions being more accurate and also greatly facilitates a development of a novel medical therapy if used as a surrogate marker.

Involvement of neutrophils in machineries underlying the rupture of intracranial aneurysms in rats

“…Thus, a non-invasive imaging of the presence or the activation of this type of cells in lesions could be an ideal diagnostic method to more exactly predict the rupture of lesions or to identify rupture-prone lesions from stable ones. Nano-particle-based visualization of neutrophils using MRI as in macrophages [37][38][39] , may become a novel diagnostic method. Although the excellent specificity to neutrophils is essential as a diagnostic method to accurately reflect their presence or activity, the minimum specificity needed for usage as a diagnosis predictor still remains to be established.…”

Ferumoxytol-β-glucan Inhibits Melanoma Growth via Interacting with Dectin-1 to Polarize Macrophages into M1 Phenotype

“…In a previous phase III clinical study, the intravenous iron replacement therapy with FMT was well tolerated in the patients and achieved the expected therapeutic effect without any gastrointestinal symptoms or hypotension 12 . Given its strong safety and unique characterization to label macrophages, FMT has been used to identify inflammation status and monitor therapy-mediated changes in inflammatory diseases in magnetic resonance imaging 13 , 14 . Moreover, the potential value of FMT in tumor therapies has recently gained great interest from researchers.…”

Circulating Treg cells from patients with cerebral aneurysms displayed deficiency in ICOS expression and function

“…Upregulation of elastase and reduction in collagen synthesis are found in human CA samples and murine CA models 3‐5 . Endothelial cells and infiltrating immune cells in the CA lesions expressed higher levels of proinflammatory molecules, such as adhesion molecules, genes involved in NO production, and proinflammatory cytokines 6‐9 …”