Macrophages play a powerful role in directing a body’s fight against disease with unique capacity to switch activity to also help rebuild damaged tissues. Unfortunately, as diseases such as cancer develop, macrophage activity is subverted, and the secretion of cytokines stopped that would normally activate anti-cancer activities of other immune cells. As a result, macrophages begin to contribute to the development and spread of cancer. To compensate for the reduction in cytokines and to correct the imbalance, targeted approaches are needed as simply injecting cytokines into the body generates high levels of systemic toxicity.
To address this, Cell Guidance Systems’ scientists “fed” macrophages with nanoscale chunks of concentrated protein in the form of PODS crystals - solid cubes able to hold a variety of cytokine cargos which can be ingested by macrophages without adverse effects to the macrophage itself. PODS are packed with protein and the macrophages cannot completely break them down. Instead, the macrophages secrete a constant stream of bioactive cytokines with the ability to instruct adjacent cells. This ability to restore and increase cytokine levels has therapeutic potential to treat diseases, in which macrophage cytokine levels are reduced, such as cancer.
There are many potential applications of PODS-loaded macrophages. Currently, they are used to study complex cellular interactions and other phagocytic cells, such as chondrocytes. Ultimately, PODS-loaded macrophages have potential to improve cytokine treatments for diseases including cancer.
“Macrophages are well known for their ability to engulf pathogens. These remarkable cells are both the body’s soldiers and builders: apart from fighting disease, they have a unique capacity to change their activity to help rebuild damaged tissues," commented Dr Michael Jones, CEO of Cell Guidance Systems. “Although highly potent, cytokines can be very toxic. This has really limited their use to treat disease. With a few exceptions, cytokines need targeted delivery and what is unique about our approach using PODS with macrophages is the ability to deliver specific cytokines from macrophages to surrounding cells. It is very exciting as there is likely therapeutic potential, particularly in diseases such as cancer.”
- ‘Phagocytosed polyhedrin-cytokine co-crystal nanoparticles provide sustained secretion of bioactive cytokines from macrophages’, bioRxiv
https://www.biorxiv.org/content/10.1101/2021.02.17.431660v2
For further information about Cell Guidance Systems’ PODS technology, please visit: https://www.cellgs.com/pods-technology.htm