PLGA and PLGA-PEG-Mal from PolySciTech used in development of cancer immunotherapy

One of the more insidious facets of cancer is that, for a variety of biochemical reasons, most cancers do not elicit an immune response from the body. The human body’s immune system is well adept at thwarting foreign cells and pathogens and is very capable of destroying many cancer cells once activated. For this reason, there has been a great deal of research in ‘immunotherapy’ which is effectively a process of vaccinating the human body against cancer so that it recognizes and destroys cancer cells as though they were pathogens. This provides for a much more selective therapy overall as compared to conventional cytotoxic chemotherapies. Recently, researchers at Dana Faber, Harvard Medical School, MIT, Howard Hughes Medical Institute, and Koch Institute for Integrative Cancer Research utilized Mal-PEG-PLGA (Cat# AI053) and PLGA (Cat # AP041) from PolySciTech (www.polyscitech.com) to generate nanoparticles with reactive exteriors. These nanoparticles were conjugated to targeting ligands via Michael’s reaction between the maleimide units and thiol-bearing antibody fragments. The formed nanoparticles were found to target immune cells and deliver immunotherapy agents to them. This research holds promise for enhanced cancer therapy. Read more: Cartwright, A.N., Hartl, C.A., Park, C.G., Schmid, D., Irvine, D.J., Freeman, G.J., Maiarana, J., Wucherpfennig, K.W., Goldberg, M.S., Subedi, N. and Puerto, R.B., 2017. T cell-targeting nanoparticles focus delivery of immunotherapy to improve antitumor immunity. Nature communications, 8, p.1747. https://www.nature.com/articles/s41467-017-01830-8

“Abstract: Targeted delivery of compounds to particular cell subsets can enhance therapeutic index by concentrating their action on the cells of interest. Because attempts to target tumors directly have yielded limited benefit, we instead target endogenous immune cell subsets in the circulation that can migrate actively into tumors. We describe antibody-targeted nanoparticles that bind to CD8+ T cells in the blood, lymphoid tissues, and tumors of mice. PD-1+ T cells are successfully targeted in the circulation and tumor. The delivery of an inhibitor of TGFβ signaling to PD-1-expressing cells extends the survival of tumor-bearing mice, whereas free drugs have no effect at such doses. This modular platform also enables PD-1-targeted delivery of a TLR7/8 agonist to the tumor microenvironment, increasing the proportion of tumor-infiltrating CD8+ T cells and sensitizing tumors to subsequent anti-PD-1. Targeted delivery of immunotherapy to defined subsets of endogenous leukocytes may be superior to administration of free drugs.”