Therapeutic Applications of Monoclonal Antibodies

Summary

This video explores the therapeutic applications of monoclonal antibodies (mAbs), highlighting their use in treating autoimmune diseases and cancers. mAbs, known for their higher specificity and fewer side effects compared to traditional treatments, include types like murine, chimeric, humanized, and fully human antibodies. The video discusses several FDA-approved mAb drugs, such as Humira for rheumatoid arthritis, Rituxan for lymphoma, Herceptin for cancer, and Avastin for inhibiting tumor growth. mAbs work through mechanisms like immune system activation, growth signal blockage, anti-angiogenesis, and targeted radiation delivery, offering more precise and effective treatments with minimal side effects.

Takeaways

• 😀 Monoclonal antibody (mAb) treatments have fewer side effects than traditional therapies due to their higher specificity.
• 😀 There are four types of monoclonal antibodies: murine, chimeric, humanized, and fully human, each with varying levels of human content.
• 😀 Monoclonal antibodies are named based on their origin, with murine mAbs ending in 'omab', chimeric in 'ximab', humanized in 'zumab', and fully human in 'umab'.
• 😀 Fully human monoclonal antibodies, like adalimumab (Humira), have entirely human origins and are more effective with fewer side effects.
• 😀 Chimeric mAbs, such as abciximab (Reopro), contain murine variable regions and human constant regions and are used for preventing blood clotting.
• 😀 Omalizumab (Xolair) is an example of a humanized mAb, used to treat asthma by blocking IgE binding and interrupting allergic reactions.
• 😀 Monoclonal antibodies are utilized in cancer treatments through mechanisms such as opsonization, apoptosis, and blocking growth signals.
• 😀 Rituximab (Rituxan) is a chimeric mAb that targets CD20 to treat chronic lymphocytic leukemia by making cancerous B cells more visible to the immune system.
• 😀 Cetuximab (Erbitux) blocks epidermal growth factor receptors (EGFR) to inhibit cancer cell growth in colon and head/neck cancers.
• 😀 Bevacizumab (Avastin) is a humanized mAb that inhibits vascular endothelial growth factor (VEGF) to prevent the formation of blood vessels that feed tumors.
• 😀 Monoclonal antibodies like ibritumomab tiuxetan (Zevalin) deliver radiation directly to cancer cells, offering a targeted treatment approach with fewer side effects.

Q & A

What are monoclonal antibodies (mAbs)?

Monoclonal antibodies (mAbs) are lab-made molecules designed to mimic the immune system's ability to fight off harmful pathogens such as viruses and bacteria. They are highly specific and can target particular antigens on cells or pathogens.

Why do monoclonal antibody treatments have fewer side effects compared to traditional treatments?

Monoclonal antibody treatments are more specific to their target, meaning they are less likely to affect healthy cells and tissues. This high specificity reduces off-target therapeutic effects, leading to fewer side effects.

What are the four types of monoclonal antibodies (mAbs)?

The four types of monoclonal antibodies are murine (derived from mice), chimeric (combining mouse and human components), humanized (mostly human with a few mouse-derived regions), and fully human (completely human in origin).

What is the difference between humanized and chimeric monoclonal antibodies?

Humanized monoclonal antibodies are almost entirely human, except for the complementarity-determining regions (CDRs), which are derived from mice. Chimeric monoclonal antibodies contain mouse variable regions and human constant regions.

How are monoclonal antibodies used in the treatment of autoimmune diseases?

Monoclonal antibodies can target specific proteins involved in immune responses, such as tumor necrosis factor (TNF), which causes inflammation in autoimmune diseases like rheumatoid arthritis. By neutralizing TNF, mAbs help reduce inflammation and tissue damage.

What is the function of *Adalimumab* (Humira) in treating autoimmune diseases?

*Adalimumab* (Humira) is a monoclonal antibody that targets and neutralizes TNF, a protein involved in inflammatory processes. By blocking TNF, Humira helps reduce inflammation and prevent damage in autoimmune disorders like rheumatoid arthritis.

What role do monoclonal antibodies play in cancer treatment?

Monoclonal antibodies in cancer treatment can work by making cancer cells more visible to the immune system, blocking growth signals, preventing angiogenesis (new blood vessel formation), and even delivering radiation directly to cancer cells.

What is the function of *Rituximab* (Rituxan) in cancer treatment?

*Rituximab* (Rituxan) is a chimeric monoclonal antibody that targets CD20 on B cells. By binding to CD20, it helps make cancerous B cells more visible to the immune system and promotes their destruction via antibody-dependent cell-mediated cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC).

How does *Bevacizumab* (Avastin) help treat cancer?

*Bevacizumab* (Avastin) is a humanized monoclonal antibody that targets vascular endothelial growth factor (VEGF), a protein involved in blood vessel formation. By blocking VEGF, Avastin inhibits the growth of new blood vessels, thus starving tumors of the oxygen and nutrients they need to grow.

What is the primary advantage of fully human monoclonal antibodies like *Adalimumab*?

Fully human monoclonal antibodies, such as *Adalimumab*, are entirely derived from human sources, making them less likely to provoke immune responses compared to murine or chimeric antibodies. This increases their effectiveness and reduces the risk of side effects.