How does the immune system work to fight COVID-19?
How does the immune system work to fight COVID-19?
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When our bodies are exposed to pathogens - tiny, foreign organisms such as viruses, bacteria, fungi, worms and other invaders - our natural defense called the 'immune system' tries to protect us and keep us healthy. When the body senses that the pathogen, in this case, COVID-19, is trying to get into the body through the nose, mouth, or eyes, it launches into the first part of this defense called the 'innate immune system.' A. Innate Immune System This part of the immune system tries to prevent the virus from spreading and reproducing in our bodies, and from moving around in our bodies. The innate immune system is made up of several types of defenses, including the skin and body openings (like the mouth and nose); different white blood cells to defend our bodies from pathogens; and different substances in bodily fluids and the blood to try and stop the virus from reproducing. This system tries to prevent the virus from entering the body through the mouth, nose, and eyes, but if the virus does get inside a person, then white blood cells will move toward the virus' location and cause an increase in blood circulation there so it becomes hot and swollen while the body might also produce a fever (as high temperatures can sometimes kill pathogens). At this point, other cells in the blood and tissue try to enclose the virus and eat the viral particles. But if after four to seven days, the innate immune system is not able to kill all of the virus and the virus causes an infection, the adaptive immune system will begin to defend the body. B. Adaptive Immune System The adaptive immune response, also called the acquired immune system, is a much more focused effort to target and destroy the foreign threat: the virus. Two important parts of the adaptive immune system are white blood cells called B cells and T cells. B cells create antibodies - small proteins that attach** **to unique parts of each pathogen called 'antigens'. When your body senses a particular antigen attached to the virus in the body, B cells then creates antibodies that can connect to those antigens using a specific shape that was created to match it. Meanwhile, T cells try to kill the antigen like an army fighting off an invader. Some T cells also help B cells make antibodies while others are busy working to stop the virus from reproducing in your body and spreading to different parts of your body. This part of the adaptive immune response also creates longer term memory of the virus that will help it fight off the virus if it is exposed to it again in the future, and to launch its defenses more quickly. Researchers are now studying how long-term this memory-based immunity lasts and how strong it is in defending against COVID-19 infection in the future. C. Conclusion Hopefully at this point, the innate and adaptive immune systems are able to kill the virus and create some immunity to it. If not, the immune system continues working to fight off the virus, but symptoms might worsen as the body weakens after spending so much energy to fight off the virus. In some cases, COVID-19 might impact organs so severely that it can result in death.
When our bodies are exposed to pathogens - tiny, foreign organisms such as viruses, bacteria, fungi, worms and other invaders - our natural defense called the 'immune system' tries to protect us and keep us healthy. When the body senses that the pathogen, in this case, COVID-19, is trying to get into the body through the nose, mouth, or eyes, it launches into the first part of this defense called the 'innate immune system.' A. Innate Immune System This part of the immune system tries to prevent the virus from spreading and reproducing in our bodies, and from moving around in our bodies. The innate immune system is made up of several types of defenses, including the skin and body openings (like the mouth and nose); different white blood cells to defend our bodies from pathogens; and different substances in bodily fluids and the blood to try and stop the virus from reproducing. This system tries to prevent the virus from entering the body through the mouth, nose, and eyes, but if the virus does get inside a person, then white blood cells will move toward the virus' location and cause an increase in blood circulation there so it becomes hot and swollen while the body might also produce a fever (as high temperatures can sometimes kill pathogens). At this point, other cells in the blood and tissue try to enclose the virus and eat the viral particles. But if after four to seven days, the innate immune system is not able to kill all of the virus and the virus causes an infection, the adaptive immune system will begin to defend the body. B. Adaptive Immune System The adaptive immune response, also called the acquired immune system, is a much more focused effort to target and destroy the foreign threat: the virus. Two important parts of the adaptive immune system are white blood cells called B cells and T cells. B cells create antibodies - small proteins that attach** **to unique parts of each pathogen called 'antigens'. When your body senses a particular antigen attached to the virus in the body, B cells then creates antibodies that can connect to those antigens using a specific shape that was created to match it. Meanwhile, T cells try to kill the antigen like an army fighting off an invader. Some T cells also help B cells make antibodies while others are busy working to stop the virus from reproducing in your body and spreading to different parts of your body. This part of the adaptive immune response also creates longer term memory of the virus that will help it fight off the virus if it is exposed to it again in the future, and to launch its defenses more quickly. Researchers are now studying how long-term this memory-based immunity lasts and how strong it is in defending against COVID-19 infection in the future. C. Conclusion Hopefully at this point, the innate and adaptive immune systems are able to kill the virus and create some immunity to it. If not, the immune system continues working to fight off the virus, but symptoms might worsen as the body weakens after spending so much energy to fight off the virus. In some cases, COVID-19 might impact organs so severely that it can result in death.
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What our experts say
When our bodies are exposed to pathogens - tiny, foreign organisms such as viruses, bacteria, fungi, worms and other invaders - our natural defense called the 'immune system' tries to protect us and keep us healthy. When the body senses that the pathogen, in this case, COVID-19, is trying to get into the body through the nose, mouth, or eyes, it launches into the first part of this defense called the 'innate immune system.'
A. Innate Immune System
This part of the immune system tries to prevent the virus from spreading and reproducing in our bodies, and from moving around in our bodies. The innate immune system is made up of several types of defenses, including the skin and body openings (like the mouth and nose); different white blood cells to defend our bodies from pathogens; and different substances in bodily fluids and the blood to try and stop the virus from reproducing. This system tries to prevent the virus from entering the body through the mouth, nose, and eyes, but if the virus does get inside a person, then white blood cells will move toward the virus' location and cause an increase in blood circulation there so it becomes hot and swollen while the body might also produce a fever (as high temperatures can sometimes kill pathogens). At this point, other cells in the blood and tissue try to enclose the virus and eat the viral particles.
But if after four to seven days, the innate immune system is not able to kill all of the virus and the virus causes an infection, the adaptive immune system will begin to defend the body.
B. Adaptive Immune System
The adaptive immune response, also called the acquired immune system, is a much more focused effort to target and destroy the foreign threat: the virus. Two important parts of the adaptive immune system are white blood cells called B cells and T cells. B cells create antibodies - small proteins that attach to unique parts of each pathogen called 'antigens'. When your body senses a particular antigen attached to the virus in the body, B cells then creates antibodies that can connect to those antigens using a specific shape that was created to match it.
Meanwhile, T cells try to kill the antigen like an army fighting off an invader. Some T cells also help B cells make antibodies while others are busy working to stop the virus from reproducing in your body and spreading to different parts of your body. This part of the adaptive immune response also creates longer term memory of the virus that will help it fight off the virus if it is exposed to it again in the future, and to launch its defenses more quickly. Researchers are now studying how long-term this memory-based immunity lasts and how strong it is in defending against COVID-19 infection in the future.
C. Conclusion Hopefully at this point, the innate and adaptive immune systems are able to kill the virus and create some immunity to it. If not, the immune system continues working to fight off the virus, but symptoms might worsen as the body weakens after spending so much energy to fight off the virus. In some cases, COVID-19 might impact organs so severely that it can result in death.
When our bodies are exposed to pathogens - tiny, foreign organisms such as viruses, bacteria, fungi, worms and other invaders - our natural defense called the 'immune system' tries to protect us and keep us healthy. When the body senses that the pathogen, in this case, COVID-19, is trying to get into the body through the nose, mouth, or eyes, it launches into the first part of this defense called the 'innate immune system.'
A. Innate Immune System
This part of the immune system tries to prevent the virus from spreading and reproducing in our bodies, and from moving around in our bodies. The innate immune system is made up of several types of defenses, including the skin and body openings (like the mouth and nose); different white blood cells to defend our bodies from pathogens; and different substances in bodily fluids and the blood to try and stop the virus from reproducing. This system tries to prevent the virus from entering the body through the mouth, nose, and eyes, but if the virus does get inside a person, then white blood cells will move toward the virus' location and cause an increase in blood circulation there so it becomes hot and swollen while the body might also produce a fever (as high temperatures can sometimes kill pathogens). At this point, other cells in the blood and tissue try to enclose the virus and eat the viral particles.
But if after four to seven days, the innate immune system is not able to kill all of the virus and the virus causes an infection, the adaptive immune system will begin to defend the body.
B. Adaptive Immune System
The adaptive immune response, also called the acquired immune system, is a much more focused effort to target and destroy the foreign threat: the virus. Two important parts of the adaptive immune system are white blood cells called B cells and T cells. B cells create antibodies - small proteins that attach to unique parts of each pathogen called 'antigens'. When your body senses a particular antigen attached to the virus in the body, B cells then creates antibodies that can connect to those antigens using a specific shape that was created to match it.
Meanwhile, T cells try to kill the antigen like an army fighting off an invader. Some T cells also help B cells make antibodies while others are busy working to stop the virus from reproducing in your body and spreading to different parts of your body. This part of the adaptive immune response also creates longer term memory of the virus that will help it fight off the virus if it is exposed to it again in the future, and to launch its defenses more quickly. Researchers are now studying how long-term this memory-based immunity lasts and how strong it is in defending against COVID-19 infection in the future.
C. Conclusion Hopefully at this point, the innate and adaptive immune systems are able to kill the virus and create some immunity to it. If not, the immune system continues working to fight off the virus, but symptoms might worsen as the body weakens after spending so much energy to fight off the virus. In some cases, COVID-19 might impact organs so severely that it can result in death.
Context and background
One of the reasons it can be difficult to understand how the immune system responds to the virus that causes COVID-19 (and all viruses) is because everyone's immune system is unique. After being infected, each of us produces different levels of antibodies -- these are proteins that attach to the antigens (any substance, usually a protein, that triggers your immune system to produce antibodies against it) and attack them. These differences can impact how long patients remain sick with COVID-19 and how severe their cases can be. A further complicating factor is that non-active parts of the virus can still cause your immune system to overreact, as if the virus is still reproducing in your body, when it isn't really doing that.
Inducing an immune response in our body is also a crucial component of vaccine development. A successful vaccine must produce antibodies to prepare our bodies to defend against the virus if we are exposed to it again in the future. The better a vaccine can mimic a natural infection, the better it will be able to trigger an immune reaction that mimics a natural immune response.
One of the reasons it can be difficult to understand how the immune system responds to the virus that causes COVID-19 (and all viruses) is because everyone's immune system is unique. After being infected, each of us produces different levels of antibodies -- these are proteins that attach to the antigens (any substance, usually a protein, that triggers your immune system to produce antibodies against it) and attack them. These differences can impact how long patients remain sick with COVID-19 and how severe their cases can be. A further complicating factor is that non-active parts of the virus can still cause your immune system to overreact, as if the virus is still reproducing in your body, when it isn't really doing that.
Inducing an immune response in our body is also a crucial component of vaccine development. A successful vaccine must produce antibodies to prepare our bodies to defend against the virus if we are exposed to it again in the future. The better a vaccine can mimic a natural infection, the better it will be able to trigger an immune reaction that mimics a natural immune response.
