A Series Approach to Disease Treatment is Provided by Macrophage-targeted Drug Delivery

It is well known that macrophages play a critical role in preserving the steady state of the immune system and are involved in the process of cancer and inflammation. Thus, macrophage-targeted drug delivery has the potential to transform disease treatment.

Indeed, macrophage-targeted drug delivery systems have gained significant scientific interest in recent years due to their superior properties such as good biocompatibility, possible long circulation, intrinsic homing properties, and ability to permeate biological barriers. For instance, proinflammatory M1 macrophages can phagocytose tumor cells, whereas anti-inflammatory M2 macrophages such as tumor-associated macrophages (TAMs) promote tumor growth and invasion. Based on these exciting results, the use of a macrophage-targeted drug delivery system with various features has been greatly expanded in order to investigate and treat diseases such as cancer, inflammation, and HIV infection.

Several studies have shown that macrophages can be employed to efficiently transport a wide range of chemicals. Macrophage membranes, for example, can incorporate NPs, liposomes, and chitosan. Macrophages can also be loaded with nanozymes and other natural small-molecule drugs while retaining their biological activity.

Macrophages can be engineered to transport drug nanoparticles (NPs) to tumor sites in a targeted manner, thereby exerting significant anticancer effects. For instance, TAMs can promote tumor growth via angiogenesis and metastasis, thereby being a potential target for cancer therapy by nano drugs. Meanwhile, based on the high plasticity of TAMs, it is possible to achieve a tumoricidal phenotype by reprogramming these cells. Macrophage-targeted nanoparticle drug delivery systems have been widely used after several decades of technological development, and the application of macrophage-targeted nanoparticles to treat inflammatory diseases, cancer, and cardiovascular diseases has ushered in an upsurge of research.

As particulate carriers, besides, liposomes are the most widely investigated delivery system, providing advantages such as low immunogenicity, biocompatibility, cell specificity, and drug protection. More importantly, liposome encapsulation can change the geographical and temporal distribution of the encapsulated drug molecules in the body, thus reducing undesirable toxic side effects and increasing treatment efficacy. Studies revealed that compared to non-liposomal oral delivery, liposomal delivery did attenuate effects on liver weight and liver and kidney PPAR target gene expression. Therefore, macrophage-targeted liposome drug delivery systems promise to be an efficient method in the field of diseases.

Overall, these macrophage-targeted drug delivery systems truly provide significant support for disease treatment. There is still significant room for the development of macrophage-targeted drug delivery, which will further enhance current tumor and other disease therapies.