What are Antibodies and How Do They Work?
Posted: Mar 23rd, 2022 at 12:00AM
Immunity remains a significant discussion — and concern — as the world tries to contain and mitigate the COVID-19 pandemic. The topic of immunization after a COVID-19 infection continues to be studied and explored by experts.
Immunity occurs when an antibody stays in the body after an individual has recovered from an illness. Antibodies form as a part of the body's response to a pathogen, and they are crucial in protecting your body against a lot of viruses and bacteria, preventing diseases from causing severe harm and complications.
But what are antibodies exactly, and how do they work to boost the body's immune system? Read on to find out.
What are Antibodies?
Antibodies, also called immunoglobulin, are specialized proteins produced by the immune system in response to foreign substances or pathogens entering the body. Pathogens can range from microorganisms, bacteria, and fungi to parasites and viruses that are attempting to use the body as a host to divide and multiply.
Antibodies act upon a search-and-destroy operative, working like scouts of the immune system to locate intruders and identify them for the body to destroy. After the body recovers from an infection, the immune system will remember how to produce the specific type of antibodies that can put up a fight against that particular pathogen that caused the infection.
Antibodies don't only work as the body's defenders against viruses and bacteria, but they also serve as a good benchmark for how strong an individual's immune system is against a pathogen.
How Do Antibodies Work?
When a pathogen enters the body, it first meets a type of cell called the B cells. Also referred to as B lymphocytes, these cells are produced in the bone marrow and located in the lymph and blood. Upon encountering pathogens, B cells will produce antibodies.
Antibodies have a distinct Y shape, which serves as a lock-and-key function. Once the antibodies are released by the B cells, they begin to search for the location of the foreign substance — also called antigens — in the body. Located at the tips of antibodies are unique sites which they use to bind to thousands, even millions, of various antigens, destroying the antigens themselves or tagging them for the other immune system cells to destroy.
T cells are then deployed to recognize and attack the marked antigens. After the antigens have been destroyed, phagocytes, which are large cells that swallow alien substances, will come to clean up the scene and consume the remains of the infection.
The antibodies stay in the body even after the infection is gone. They remain there in waiting in case the same type of antigen returns. If you get the common cold and recover, the antibody that was produced by your immune system to destroy the virus that caused your sickness will stay in your body, and it will be ready should the same common cold virus invade your system again. It will instantly bind with the pathogen, call for the phagocytes and T cells much faster, and prevent the infection from doing any damage much quicker.
What are the Types of Antibodies?
There are five types of antibodies or immunoglobulins, which can be characterized by their function and location in the body:
- IgG (immunoglobulin G): The smallest antibody but accounts for 75% of antibodies found in all the body fluids; plays an essential role in tagging pathogens or directly destroying them; the only antibodies that can pass over the placenta from mother to fetus.
- IgA (immunoglobulin A): Located in mucosal tissues, respiratory and digestive passages, and saliva, breast milk, and tears; the first line of defense and binds with pathogens to mark them for destruction.
- IgM (immunoglobulin M): The first and largest antibody to respond to infection; a subset of IgM aids B cells to “remember” an antigen after it has been killed.
- IgD (immunoglobulin D): Only accounts for .025% of antibodies in the body, located in the stomach and chest cells; little is known about its role in other immune functions.
- IgE (immunoglobulin E): Responsible for allergic responses and symptoms and is commonly found in the lung, skin, and mucosal membranes.
What is an Antibody Test?
Antibody testing, also known as titer testing, is performed to determine the number of antibodies in your body, evidence of recent infection, and to know if your body's prepared to fight off a specific virus or bacteria.
Antibody titer testing is a common way to test your body's preparedness against certain illnesses. e7 Health offers titer testing to check your immune status from previous vaccinations or infections against the following diseases:
- Hepatitis A
- Hepatitis B
- MMR
- Varicella (Chickenpox)
- Rabies
While there's a possibility of side effects, including dizziness, soreness, and feeling faint at the sight of your blood, the test is a relatively low-risk procedure and will be overseen by a healthcare provider.
Getting a positive result means you may have received vaccinations or you've been exposed to the virus in the past. On the other hand, a negative result can indicate a need to follow up on your vaccinations or booster shots.
COVID-19 Antibody Testing
While the level of immunity and how long immunity lasts after a COVID-19 infection remain unknown, a COVID-19 antibody test is a good indication if you've been recently infected or if you have some immunity against COVID-19. A positive antibody test will tell you that you have several antibodies against COVID-19, which could've been created because of past infection with SARS-CoV-2 itself or from the COVID-19 vaccines.
e7 Health offers an antibody test for COVID-19, as well as a PCR saliva test to determine if you're currently dealing with an active infection. If you're thinking of getting an antibody test, keep in mind that the CDC recommends that you take an antibody test at least three weeks after symptoms have started to give your immune system some time to make antibodies needed to fight COVID-19.
e7 Health to schedule a same-day or next-day appointment at a location near you.
