Monoclonal Antibodies, MOABs or MABs, are a form of immunotherapy. They are currently the number one type of immunotherapy used for cancer patients.
The job of human antibodies is to mark foreign antigens that are on cells. This marking labels them for destruction by macrophages. Many researchers believe the body destroys cancer cells identified as foreign antigens on a regular basis, however; when the immune system is compromised the cancer cells are able to gain control.
Monoclonal antibodies are made in the laboratory using clones of “humanized” antibodies. This done by injecting human cancer cells into mice. The mice then produce antibodies to fight the cancer cells. Researchers combine these antibodies with laboratory grown antibodies and then they are injected into a vein.
Inside the body the antibodies can do several things such as:
- Stimulate the human immune system to recognize and destroy cancer cells
- Toxins can be attached to the antibodies which will destroy the cancer cells
- Radioactive particles can be attached to the antibodies to destroy cancer cells
- Block receptors which signal growth cells that help the cancer grow
Some monoclonal therapy is given with chemotherapy and some is given alone. It is important to note that monoclonal antibodies are antigen specific, targeted to a specific type of cell. An antigen protein that is targeted at breast cancer cells will not work for lymphoma.
There are side effects of this therapy including the fact that sometimes the antibodies do not recognize the cells and doesn’t do the intended job, which is why monoclonal therapy is often given with other therapies. It is also possible and likely that eventually the body will produce its own antibodies that will destroy the “humanized” antigens.
Other Side Effects of Monoclonal Antibodies May Include:
- Allergic reaction to the antibodies
- Flu-like symptoms
- Low blood counts
Types of Monoclonal Antibodies currently approved by the FDA for cancer:
- Alemtuzumab-Sampath-Chronic Lymphocytic Leukemia
- Bevacizumab-Avastin-Colorectal Cancer
- Cetuximab-Erbitux-Colorectal Cancer
- Ibitrumomab-Zevalin-Non-Hodgkin Lymphoma
- Panitumumab-Vectibix-Colorectal Cancer
- Gemuzamab ozogamicin-Mylotarg-Acute Myelogenous Leukemia
- Rituximab-Tituxin, Mabthera-Non-Hodgkin Lymphoma
- Tositumomab-Bexxar-Non Hodgkin Lymphoma
- Trastuzumab-Hereceptin-Breast Cancer
The Lymphoma Information Network provides a great webcast which explains Monoclonal Antibodies.
The American Cancer Society: Monoclonal Antibodies