The Scattering of Gold Nanorods Combined with Differential Uptake, Paving a New Detection Method for Macrophage Subtypes Using Flow Cytometery

Abstract

The strategy of identification for M1 and M2 macrophages both in vivo and in vitro would help to predict the health condition of the individual. Here, we introduced a solution to this problem with the advantage of both the phagocytic nature of macrophages and the scattering effect of gold nanorods (GNRs). The internalized GNRs, relating to their extent of intake, caused a conspicuous scattering profile at the red channel in flow cytometry, overruling the contribution of the cellular side scatters. This internalization is solely governed by the surface chemistry of GNRs. The PAH-GNRs showed maximum intake potency followed by Cit-, PSS-, and PEG-GNRs. On a substantial note, PAH-GNRs lead to differential uptake between M1 and M2 cells, with three times higher intake in M2 cells over M1. This is the first report of employing the scattering of unlabeled GNRs to discriminate M1 and M2 cell types using a flow cytometer.

SARS-CoV-2 Detection Using Colorimetric Plasmonic Sensors: A Proof-of-Concept Computational Study

“…Any other shape will require studying the variations in the orientation of the AuNPs in addition to their location and the percentage coverage of the virus' surface. For example, gold nanorods are asymmetric which causes them to exhibit both longitudinal and/or transverse resonances based on their orientation [6], [8]. Therefore, the orientation of each gold nanorod on the surface of the virus needs to be varied to follow what happens in This randomness in orientation might enhance the bandwidth of the broadband absorption similar to what was reported in other kinds of nanostructures [35], [36].…”

“…Plasmonic nanoparticles have been used to accurately detect a wide range of cells and biomarkers [6]- [8]. For example, gold nanorods have been recently proposed to detect and classify macrophages, which are a kind of white cells released by the immune system [6]. Chakraborty et al studied the differences in gold nanorods uptake by the M1 and M2 macrophages.…”

“…Chakraborty et al studied the differences in gold nanorods uptake by the M1 and M2 macrophages. They showed that the uptake of poly(allylamine hydrochloride) (PAH) coated gold nanorods by M2 macrophages was three times higher than the uptake by M1 macrophages [6]. By monitoring the scattering characteristics of the sample, this differential uptake can be used to predict the ratio of the M1 macrophages to the M2 macrophages, which can classify a wide range of infectious diseases and cancer and diagnose its current stage [6].…”

Gold nanorods enhance different immune cells and allow for efficient targeting of CD4+ Foxp3+ Tregulatory cells

“…Furthermore, at the early time point, we did not see a change in cell granularity, as analyzed by side scatter area ( S12 Fig ). It is noteworthy that changes in cellular granularity were reported after macrophages internalized AuNRs [ 53 ].…”

Gold Nanorods-Based Photothermal Therapy: Interactions Between Biostructure, Nanomaterial, and Near-Infrared Irradiation

“…Exploiting the interactions between AuNRs and cells enables the identification of M1 and M2 macrophages in vitro and in vivo, promotes cell proliferation and cancer cell death, and modulates the cellular activity and behavior [ 46 , 47 ]. The complex system of PEG and terminal amine-functionalized AuNRs can regulate the differentiation of adipose tissue-derived human mesenchymal stem cells into neural-like progenitor cells [ 48 ].…”