What is the immune system?

What is the immune system?

The immune system is a vital part of your body’s efforts to keep you alive and well. You may be aware that certain foods and drinks are thought to be good for your immune system, but how much do you know about how it actually works? 

Keep reading to learn more about the immune system.

What is the role of the immune system?

Simply put, the immune system is how your body fights off infections and diseases. You won’t find it in any one part of your body; in fact, it is a complex system that includes different organs, proteins and cells that all play a role in protecting you from infection. Your immune system can defend against infectious organisms known as pathogens without you even noticing, but this isn’t always the case[1].

Sometimes, it takes a little bit longer to fight off the pathogen, which is when you might notice symptoms of the disease or infection. Depending on the illness, it may only be necessary to treat the symptoms with simple medications like Chloralieve’s soothing throat lozenges. This way, you let your body tackle the illness and improve your immunity to that disease.

Although it’s rare, some people have problems with their immune system that stop it from working properly. These conditions are known as autoimmune disorders and there are treatments available to limit their impact on a person’s daily life[1].

How does the immune system work?

The immune system has multiple lines of defence that help it to tackle pathogens and diseases. These are split into two categories: the nonspecific or innate immune system, and the specific or adaptive immune system. When a pathogen enters the body, it first encounters the innate immune system. If it gets past the innate immune system, then the adaptive immune system steps up to attack the pathogen[1].

What is the innate immune system?

In this context, the term ‘innate’ means essential or inherent. It refers to the immune responses that are always active and therefore aren’t reacting to any one specific pathogen. This can include things like the skin, which acts like the walls of a castle to reduce the likelihood of pathogens entering the body. 

However, other parts of the innate immune system can be reactive. For example, coughing is a natural response to inhaling dust or smoke that irritates the throat. While this is a reactive response, it’s not targeted towards any specific type of pathogen – anything that irritates your throat is likely to make you cough. 

Another example of the innate immune system is mucus or phlegm production. While you always have some amount of mucus production occurring to keep you healthy, you’ll often produce more phlegm when you’re ill. This has the effect of trapping any germs or pathogens in the phlegm to be removed via coughing[2]

What is the adaptive immune system?

It might be easier to understand the nonspecificity of the innate response by contrasting it with the adaptive response. When pathogens get past the innate response, your body starts to make cells that can attack the pathogens. These cells are purpose built to attack that type of pathogen, either directly or by secreting antibodies to disrupt infection. 

Once the infection is dealt with, your body remembers how to make those specific cells, so that the next time those pathogens get into your body, the immune response is quicker. When the second infection happens, your body doesn’t need to spend time figuring out what to do, because it already effectively has an instruction manual for fighting off that pathogen.

This is why mutating pathogens are a worry for doctors. If a pathogen mutates and changes, the old instructions your body has been using won’t work anymore, which means you’ll spend more time fighting off the infection[2].


[1] https://www.betterhealth.vic.gov.au/health/conditionsandtreatments/immune-system

[2] https://www.ncbi.nlm.nih.gov/books/NBK279396/ InformedHealth.org [Internet]. Cologne, Germany: Institute for Quality and Efficiency in Health Care (IQWiG); 2006-. The innate and adaptive immune systems. [Updated 2020 Jul 30].