Macrophages

Macrophages play an important role in human immune systems. Macrophages are born from white blood cells called monocytes, which are produced by stem cells in our bone marrow. Macrophages engulf and digest cellular debris, foreign substances, microbes, viruses and cancer cells by a process known as phagocytosis.  Macrophages live for months, patrolling our cells and organs and keeping them clean. 

Uses for Macrophages

These scavenger cells can sometimes cause problems in the body. When macrophages become activated, they can actually cause harm, rather than simply protecting the body from something foreign. These cells have been implicated in the development of many macrophage-associated disorders including cancer, rheumatoid arthritis, CNS, inflammatory, infectious, and other autoimmune diseases.  Some types of cancer also appear to be effected by macrophages causing them to protect the tumor from immune response, and these cells can be hijacked by viruses such as HIV and used to spread it in the body.

Activated Macrophages Highly Express CD206, the Mannose Receptor

Early clinical trials suggest that macrophages may be an attractive target in cancer treatment among other disorders. Macrophages are a dominant cell population found in the tumor microenvironment. Accumulating evidence suggests that these tumor-associated macrophages (TAMs) actively promote all aspects of tumor initiation, growth, and development.   Macrophages can also be immunosuppressive, preventing tumor cell attack by natural killer and T cells during tumor progression and after recovery from chemo- or immunotherapy.

A biochemical marker such as CD206 expressed by tumor-associated macrophages has the potential to identify only those suppressive macrophages that have been reprogrammed by the tumor. The Manocept platform has been proven to target CD206 and may lead to the development of therapeutic approaches that specifically target these cells for deletion and, consequently, restore immune responses in the tumor following therapy.

Manocept Tumor Image

Sources:

Exploring the full spectrum of macrophage activation.Nat Rev Immunol. 2008 Dec; 8(12): 958–969. doi10.1038/nri2448  accessed July 14, 2015.

Tumor-Associated Macrophages: From Mechanisms to Therapy; Immunity Volume 41, Issue 1, p49–61, 17 July 2014.

Tumor-associated macrophages: function, phenotype, and link to prognosis in human lung cancer;  Am J Transl Res. 2012; 4(4): 376–389..

Innovations in receptor-targeted precision imaging:  Diagnosis up close and personal.  Nature; 502(7473), 2013. (Nature Outlook section S125-S130).