Monoclonal Antibodies: Overview & Applications

Monoclonal Antibodies: Overview & Applications

What are Monoclonal Antibodies?

Monoclonal antibodies are proteins developed in labs from the clone of a single B-cell. They possess an affinity for a specific antigen and are produced in large quantities to treat severe disease conditions, such as cancer.

The antibodies bind to the target locations, like antigens present on the surface of cancer cells, and initiate an immune response to protect you in a high-risk disease condition.

Scientists have developed many types of monoclonal antibodies, each having an affinity for a single type of antigen with a single type of epitope. However, there are also polyclonal antibodies that are derived from different lineages of B-cells and each possess the ability to bind to different epitopes.

The monoclonal antibodies have been used to diagnose and treat many medical conditions such as certain infectious diseases, inflammatory diseases, allergic reactions, many types of cancer, and some other conditions as well. Often they are solely used to carry certain drugs, radioactive substances, and toxins directly to diseased cells.

Furthermore, monoclonal antibodies have a strong resistance ability against viruses. That’s why the U.S. Food and Drug Administration (FDA) issued an emergency use authorization (EUA) in 2020 for considering these antibodies as a treatment option for the COVID-19 patients.

In this article, we will teach you how the monoclonal antibodies work, their side effects, and their application in disease diagnosis and treatment.

Need new or refurbished lab equipment? Excedr leases.

See our equipment list and browse a sample selection of what we can source. Or, if you’re ready, request an estimate.

How Do Monoclonal Antibodies Work?

The working mechanism of monoclonal antibodies is similar to normal antibodies in our body. After identifying an invader like bacteria, viruses, or other pathogens, our immune system starts producing antibodies. These antibodies bind to certain components (called antigens) present on the pathogen’s surface and trigger the immune system for its destruction.

However, there can be multiple ways or pathways in which monoclonal antibodies perform their functions. This means it can specifically identify and bind the target, and perform its actions by either triggering, inhibiting, mimicking, or restoring immune system functions.

For example, in terms of COVID-19, which is caused by the SARS-CoV-2 virus, the monoclonal antibodies attach to the spike protein of the coronavirus. The binding blocks the virus’s ability to enter its host cell and slows down the infection.

Thus, during the 2020 coronavirus global pandemic, the Food and Drug Administration (an agency within the Department of Health and Human Services, or HSS) authorized many monoclonal antibody therapies, such as monoclonal antibody infusion treatment product, bebtelovimab, to treat COVID-19.


Infusion therapy involves the administration of drugs intravenously or subcutaneously using a needle or catheter. It’s an effective method to deliver drugs with precision. For example, sotrovimab, an FDA-approved monoclonal antibody therapy, is used to treat diseases caused by different variants of the SARS-CoV-2 virus.

Possible Side Effects

People receiving monoclonal antibody injections, such as bebtelovimab IV injection, might experience some side effects, such as pain, bruising, swelling, bleeding, and soreness at locations injected by the healthcare providers.

Some severe and rare side effects, such as allergic reactions, might also be observed in some patients. In the case of COVID-19 patients, they might have reduced immune responses to the COVID-19 vaccine and the antibody might interfere in fighting off future infections. Therefore, it’s essential to talk to your healthcare provider in case of any concerns.

What Are Monoclonal Antibodies Used For?

Whenever our body is attacked by a new virus or pathogen for the first time, our immune system is unable to recognize it. As a result, it takes longer to respond and destroy the invader.

For such cases, monoclonal antibodies were designed by scientists to be introduced to patients and help trigger their immune response to fight the new virus or pathogen. Monoclonal antibodies are widely used for the treatment of several diseases, including cancer, autoimmune disorders, and viral infections.


During the COVID-19 public health emergency, the FDA approved monoclonal antibody therapies to reduce hospitalization for patients with positive COVID-19 tests and a higher risk of developing severe symptoms.

The four infusion therapies approved for the treatment of COVID-19 are:

  • Tocilizumab
  • Sotrovimab
  • Bebtelovimab
  • The combination of tixagevimab and cilgavimab (or EVUSHELD)

The outpatient treatments, tocilizumab and sotrovimab, are used to treat mild to moderate COVID-19 in adults and children over 12 years of age who may be at high risk for severe COVID-19. Whereas, bebtelovimab as inpatient treatment is used to treat hospitalized adults and 2 years old children infected with the coronavirus.

EVUSHELD is given to adults and children of 12 years or more, weighing at least 88 pounds, and is immunocompromised for pre-exposure prophylaxis of COVID-19.

Additionally, other than being more than 12 years old, one can also take the therapy if there are any underlying health conditions present, such as asthma, hypertension, or cardiovascular diseases.


Even though many monoclonal antibodies are in clinical trials to be tested for their efficacy and utility in treating cancers, some are being used in hospitals as part of standard treatments.

There are multiple ways in which these antibodies act on cancer cells, such as:

  • Flagging the cancer cells to help the immune system identify these cells
  • Triggering immune responses to fight infectious diseases
  • Helping in blocking cancer cell growth
  • Blocking protein-protein interaction, thus, limiting the growth of blood vessels in cancer cells
  • Directly attacking cancerous cells and causing their destruction
  • Combining with other chemotherapy drugs to deliver at targeted locations having cancerous growth

Monoclonal Antibody Treatments

Assuring the safety and security of public health, the FDA gave emergency authorization to some monoclonal antibody products for COVID-19. Some of these therapies are explained below.


Bebtelovimab is an outpatient treatment for COVID-19. The bebtelovimab 175 mg intravenous (IV) injection is used as a treatment for COVID-19 patients of more than 12 years, after seven days of COVID symptoms. It’s especially useful as an alternative COVID-19 treatment that is recommended in the absence of ritonavir-boosted nirmatrelvir (Paxlovid) and remdesivir, or when these treatments aren’t feasible to use.


Sotrovimab is effective against severe acute respiratory syndrome coronavirus 2 or SARS-CoV-2. The monoclonal antibody targets RBD epitopes present across the entire family of SARS-like coronaviruses and protects the host against the diseases.

The emergency use authorization (EUA) for sotrovimab is for non-hospitalized patients 12 years of age or older, who weigh more than 88 lbs with mild or moderate symptoms, and who have at least one risk factor of developing a severe illness.

Don’t have the budget to purchase lab equipment outright? Consider leasing through Excedr to save your lab time and money. Browse your leasing options today!

Procure Your R&D Lab Needs with Excedr

Monoclonal antibodies are proteins designed in labs to treat severe diseases, such as viral infections like COVID-19 and many types of cancer. They work in the same way as our natural antibodies work in our bodies, but with more specificity. They recognize specific foreign pathogens, such as bacteria and viruses, and trigger the immune responses to cause their destruction.

Some examples of monoclonal antibody treatments are bebtelovimab and sotrovimabs which have been recommended by the FDA to treat COVID-19 patients. The side effects of using these treatments are swelling, bruises, bleeding, and pain at the location where it’s injected by the doctors.

If you’re someone working on developing these monoclonal antibodies in your labs or are trying to study them against certain diseases, you might require high-quality equipment to produce reliable data and prevent the repetition of such expensive experiments.

Leasing equipment is a great option if you are just starting out in the field and don’t have much money to invest in high-tech equipment. Moreover, the approach prevents you from paying any upfront cost to procure your desired equipment.

Excedr’s leasing solution is an affordable and flexible solution for leasing equipment for organizations of all sizes, ranging from small to giant organizational labs. We not only help you to choose the right equipment for your labs but also help you throughout the process of installing and getting started with the equipment.

Further, repair and maintenance of the acquired equipment aren’t an issue when it’s part of our leasing program. The range of equipment we have in our store is analytical equipment, biotech equipment, clinical equipment, and other general biology instruments.

Excedr’s leasing solution not only saves you money but also gives you more time to focus on experiments and achieve results.