The short answer
Monoclonal antibodies are immune system proteins made in a lab to recognize specific targets. Many are used to treat cancer, some by marking cancer cells for the immune system and others by bringing immune cells close to the cancer. They can cause side effects such as skin reactions and flu-like symptoms.
Monoclonal antibodies are immune system proteins created in the lab to recognize specific targets.
They are a type of targeted therapy, and some are also immunotherapy.
Some mark cancer cells so the immune system destroys them; others bring T cells close to cancer cells.
Many have been approved to treat a wide variety of cancers.
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The full explanation.
The simple version
Your body naturally makes proteins called antibodies. Antibodies help your immune system recognize germs that cause disease, such as bacteria and viruses, and mark them for destruction.
Monoclonal antibodies are immune system proteins that are created in the lab. Like your body's own antibodies, they recognize specific targets. Scientists design them to attach to targets found on cancer cells.
Monoclonal antibodies are lab-made proteins that lock onto specific targets on cancer cells.
How they fight cancer
Many monoclonal antibodies are used to treat cancer. They are a type of targeted cancer therapy, which means they are designed to interact with specific targets. Some are also immunotherapy, because they help turn the immune system against cancer.
They can work in a few different ways:
- Marking cancer cells. Some monoclonal antibodies mark cancer cells so that the immune system can better recognize and destroy them. For example, one antibody binds to a protein called CD20 on B cells and some cancer cells, causing the immune system to kill them. B cells are a type of white blood cell.
- Bringing T cells to the cancer. Other monoclonal antibodies bring T cells close to cancer cells. For example, one binds to both a protein on the surface of leukemia cells and a protein on the surface of T cells. This helps the T cells get close enough to respond to and kill the leukemia cells.
Which cancers they treat
Many monoclonal antibodies have been approved to treat a wide variety of cancers. Whether one is an option for you depends on your specific cancer, so your care team is the best source of information about your treatment.
Side effects to know about
Monoclonal antibodies can cause side effects, which differ from person to person. What you may have depends on how healthy you are before treatment, your type of cancer, how advanced it is, the type of antibody, and the dose. Doctors and nurses cannot know for sure when or if side effects will occur, so it is important to know the warning signs.
Like most immunotherapy, monoclonal antibodies can cause skin reactions at the needle site and flu-like symptoms.
Needle site reactions include pain, swelling, soreness, redness, itchiness, and rash.
Flu-like symptoms include chills, fatigue, fever, muscle aches and pains, nausea, vomiting, and diarrhea.
Less common but serious reactions
Monoclonal antibodies can also cause more serious problems, such as mouth and skin sores that can lead to infections, high blood pressure, congestive heart failure, heart attacks, and inflammatory lung disease.
They can cause mild to severe allergic reactions while you are receiving the drug. In rare cases, a reaction is severe enough to be life-threatening.
Some can cause capillary leak syndrome, where fluid and proteins leak out of tiny blood vessels into surrounding tissues, causing dangerously low blood pressure. Cytokine release syndrome can also occur, but it is often mild. Cytokines are immune substances, and a sudden rise in their levels can cause fever, nausea, headache, rash, rapid heartbeat, low blood pressure, and trouble breathing.
Because reactions can happen during or after treatment, tell your care team right away if you feel unwell.
Words to know
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Common questions
▸What are monoclonal antibodies?
Monoclonal antibodies are immune system proteins that are created in the lab. Your body naturally makes antibodies that help the immune system recognize germs and mark them for destruction. Like your own antibodies, monoclonal antibodies recognize specific targets.
▸How do monoclonal antibodies treat cancer?
They are a type of targeted therapy designed to interact with specific targets. Some are also immunotherapy. For example, some mark cancer cells so the immune system recognizes and destroys them, and others bring T cells close to cancer cells to help the immune cells kill them.
▸Are monoclonal antibodies the same as targeted therapy?
Monoclonal antibodies are a type of targeted cancer therapy, which means they are designed to interact with specific targets. Some monoclonal antibodies are also considered immunotherapy because they help turn the immune system against cancer.
▸Which cancers do they treat?
Many monoclonal antibodies have been approved to treat a wide variety of cancers. Your care team can tell you whether one is an option for your specific cancer.
▸What are common side effects?
Like most immunotherapy, monoclonal antibodies can cause skin reactions at the needle site (such as pain, swelling, redness, itchiness, or rash) and flu-like symptoms (such as chills, fatigue, fever, muscle aches, nausea, vomiting, and diarrhea).
▸Can monoclonal antibodies cause serious reactions?
Yes, though this is less common. They can cause mild to severe allergic reactions while you receive the drug, and in rare cases a reaction is severe. They can also cause other serious problems, so it is important to know the warning signs and tell your team if you have problems.
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