Last week, I was scrolling through social media, and this ad came out talking about some “miracle” smoothie. This juice promised to give my immune system some superpower, allowing me to have better antibodies to fight any cold or viral infection that hit my way.
Well, I have to say that, sadly, there is no such thing. There is no magical smoothie that promotes the production of better antibodies. But there is one natural way we can do that. The answer lies inside your body!
I have already posted a small introduction on antibodies, but as always, there is so much to learn. Today, I’m focusing on an impressive immune mechanism that allows us to naturally improve our antibodies, which is critical when fighting infections. To write this post, I talked to an amazing scientist and friend, Anne-Marie Aubin, MSc, who shared her expertise on this subject. As always, get ready to be amazed!
Confocal microscopy showing germinal centers following Zika virus infection. Each little circle represents one cell and germinal center B cells are shown in blue. Image kindly provided by Dr. Maria E Gentile and Dr. Ryan D Pardy.
How to find your target?
As you already know, antibodies are produced by B cells, which can recognize and fight pathogens (microorganisms that cause diseases). B cells find those pathogens via a receptor located on their surface called the B cell receptor (easy, right?!).
Ok, Stefanie, why are you talking about the B cell receptor when I want to learn about antibodies? Actually, when the B cell receptor, which is usually “stuck” (bound) to the B cell, is released, it is now called an antibody!
An essential job of the B cell receptor (or antibody) is to find the threat, for example, a cell infected with a virus. Think about the receptor as a lock; it only works if it finds the correct key (a piece of the virus). The better this lock-key interaction is, the better our B cells can perform.
So, our B cells always strive to make their B cell receptor (and their antibodies) highly specific to their target, which in our hypothetical case is the virus that is making us sick. The more specific the antibody is to its target, the better our protection will be against the infection!
So how do they do it? How do B cells improve their antibodies?
It all happens when you get infected. Specific immune cells will generate many small structures inside your body called germinal centers. These structures are not like an organ, but they will develop inside immune organs such as the spleen and lymph nodes. Think about a germinal center as a bunch of cells coming together in a small space without a membrane to hold them there.
But don’t think of this as a chaotic, unorganized “party”. On the contrary! Each cell in a germinal center has a specific job. And somehow, they know exactly where to go, making this beautifully organized and temporary structure.
Once your specific B cell, located in an immune organ, realizes an infection is around, it becomes activated. This B cell will then multiply, going from one B cell to many B cells. With the help of other immune cells, they will then “create” a germinal center structure!
Anne-Marie explained to me that this MASSIVE proliferation inside the germinal center is the cause of inflammation of our lymph nodes when we fight an infection. Have you ever felt your lymph nodes swollen when you got a cold? This was the result of your immune system in action!
But here is where some remarkable things start to happen! B cell proliferation not only increases the number of B cells around, but it also results in tiny mutations in the DNA of these cells. Stefanie, you said mutation?!? Yes, but wait, don’t get scared!
In this case, mutations on the DNA of B cells are great because these happen in the specific location where it will inform our cells how to make a B cell receptor. More precisely, at the spot where our B cell receptor “lock” will recognize the viral protein “key”.
These tiny changes will later on dictate how well our B cell receptor will bind to its target. So, these random changes make your B cells better or worse at binding to the pathogen you are infected with. Cool, right? But don’t go away yet, as it gets even better!
“Good” versus “Bad” B cells and their antibodies
The goal here is that we only want to keep the “good B cells”, which are those cells that bind very well to our target (the infected cell). But how does this happen?
Remember when I said that we have immune cells with different jobs in the germinal center? The job of some immune cells will be to “scan” these newly produced B cells. Once they find the “good B cells”, these “scanning cells” will give them some survival cues to keep the B cells alive.
But our “good B cells” are eager and don’t stop there! They can continue multiplying and making tiny mutations on their DNA, aiming to make even better and more specific B cell receptor (their future antibody)!
At the same time, the “scanning” continues, as our immune system ensures to send the survival cues to all the “good B cells”!
An illustration of the germinal center. Proliferating B cells possessing different receptors are shown on the left. On the right, we can see “scanning cells” checking how well the B cell receptor can bind a piece of the virus we are infected with. “Good B cells” bind very well to their target and these cells are great to help us fight infections.
Illustration by Kim Millar (@killieart)
The “good B cells” have now two fates
Alright, we have naturally made some great B cells (without any magical smoothie); what now?
One. Our Good B cells can become an “antibody-producing machine” (also known as plasma cells). These cells’ main objective is to pump excellent, highly specific antibodies which help us fight the infection.
Two. With all the energy and work your immune system put into making these great soldiers, you want to ensure that all that work is not lost! So, our good B cells can become memory B cells. These cells will live long and help you fight a future infection if you ever get reinfected with the same virus.
And what happened to the germinal center when the “job is done”? Well, this structure will disappear within several weeks after you get infected. And it will only form again once needed. Neat, right?!
So yeah, there’s no need to take any “superpower juice” to ensure you have great antibodies. But Anne-Marie explained to me that there is something we can do to help our body make good antibodies. And the answer is to get vaccinated!
Vaccines tell your immune system to make germinal centers like an infection would but with the fantastic added benefit of not getting you sick!
“It is because vaccines will make memory B cells! In fact, when your body faces the pathogen at which you have been vaccinated, those memory B cells can either become fantastic machines that can pump highly specific antibodies rapidly or go back into germinal centers to proliferate and redo tiny mutations to increase even more the specificity of the antibodies against the pathogen [how strongly the antibody will bind to its target] !”
One of the functions of antibodies is that they can prevent a nasty virus from entering our cells – this is called neutralization. Anne-Marie explained that “the rapid neutralization of the pathogen by the antibodies will eliminate the invader while preventing you from developing symptoms of the disease!”
“What I find nice about vaccination is that if everyone gets vaccinated for a specific pathogen, it creates collective immunity against this pathogen across the population. That will certainly prevent vaccinated people from getting sick, but what’s even better is that the transmission of this specific disease from one person to another will now be impossible.”
And yes, this actually works! Anne-Marie reminded us that “the best example of collective immunity we have to date is the eradication of smallpox in 1980 thanks to worldwide vaccination against this virus!”
That’s why it is important to go check your vaccination card, get those shots you are missing and let your immune system do all the hard work for you and everyone around you!
Thank you, Anne-Marie, for sharing your incredible knowledge and insights with us!
Keep asking questions and seeking answers.
From your immunologist – in training
Stefanie Valbon, MSc, PhD candidate
Anne-Marie Aubin, MSc, did her bachelor’s and master’s degrees in the Department of Microbiology and Immunology at the University of Montreal. For her master’s degree, she devoted her time to studying the impact of genetic variability on the humoral immune response at Dr. Sylvie Lesage’s laboratory at Centre de recherche de l’Hôpital Maisonneuve-Rosemont (CRHMR). She is now a research assistant working at the flow cytometry platform at the CRHMR.