Innate and Acquired Immune Systems

TAG TEAM ACTION AGAINST INFECTIONS AND HARMFUL SUBSTANCES

WHAT'S THE IMMUNE SYSTEM?

The immune system is an extensive network of internal organs, white blood cells (WBC), proteins (called antibodies), and chemicals. These structures and substances protect your body against foreign invaders like viruses, bacteria, fungi, and parasites that cause infection and disease. You overlook your immune system if it’s functioning properly. You get sick when it malfunctions because it’s weak or can’t mount a defence against certain disease-causing microorganisms. Harmful microorganisms your body has never met also tend to make you ill. A few of these microorganisms will only make you sick the first time you encounter them.

You’ll be amazed that your immune system fights disease-causing microorganisms, fights cancer cells, and neutralises harmful substances (e.g., moulds and dangerous chemicals) from the environment. The members of your immune system include cells, tissues, and organs.

WHAT DOES IMMUNITY MEAN WHEN IT COMES TO HEALTH?

Different parts of the immune system offer your body protection against numerous diseases. This protection is termed immunity.

HOW DOES YOUR IMMUNE SYSTEM WORK?

Your immune system starts to kick in and do its work when it meets foreign substances that your body doesn’t recognise as a part of its own. These foreign substances are called antigens. The main goal of your immune system is to recognise the antigens and eliminate them. An antigen may be a product or a part of viruses, fungi, bacteria, parasites, and chemicals that evoke an immune response. The antigens attach to particular receptors on the cells of the immune system, and a series of specialised processes are triggered in your body.

The first time your body encounters a disease-causing microorganism, it gets information from the microorganism and learns how to overcome it. Your body then produces antibodies to protect you from these microorganisms. If your body reencounters the same microorganisms, it can recognise them and fight them with antibodies. Antibodies are proteins produced by some immune system cells to protect your body.

INNATE AND ADAPTIVE IMMUNITY

Our immune system is broadly made up of two interrelated subsystems that work together to keep your body safe from harmful microorganisms and foreign substances:

Innate Immunity

It is simply the immunity that you’re born with. This type of immunity is non-specific, responding similarly to all foreign substances or antigens. Innate immunity is also known as natural immunity. Try to think of them as the first responders in an emergency. They’re quick to respond and address the problem. It’s composed of various internal and external defences:

1. Internal defences are composed of immune system cells (e.g., neutrophils, macrophages, natural killer cells, and dendritic cells), antimicrobial peptides, soluble mediators (cytokines, particular proteins), and cellular receptors.
2. External defences include physical barriers like your skin and mucous membranes. Mucosal membranes line structures and tracts in your body like the eyelids, nose, mouth, windpipe (trachea) and lungs, stomach, intestines, ureters, urinary bladder, and urethra.

Adaptive Immunity

It is the immunity that must be developed or acquired over a lifetime. It’s also called specific, learned, or acquired immunity. What’s lovely about this type of immunity is its ability to learn and adapt to fight disease-causing microorganisms that evolve. Furthermore, adaptive immunity may be subdivided into passive and active immunity.

1. Passive immunity is immunity you borrow or inherit from another source. It only lasts for a short time. An example would be antibodies found in breast milk. These antibodies give the newborn baby temporary but effective immunity to diseases the mother has encountered or was exposed to. When the baby meets these same diseases, it can defend itself, thanks to the mother’s antibodies.


2. Active immunity is the core of adaptive immunity. It develops throughout your life. You develop it when you’re exposed to diseases (natural development of antibodies) or immunised against them with vaccines (artificial development). nfluential members of this group include B-cells and T-cells (B and T lymphocytes). We’ll have more on B-cells and T-cells in future articles.

MEDICAL CONDITIONS THAT AFFECT THE IMMUNE SYSTEM

Infections

An infection like glandular fever or kissing disease (mono or mononucleosis) is a well-recognised infection that cripples your immune system. A more serious infection is an infection with HIV (human immunodeficiency virus) that diminishes your body to fight off other infections as time passes.

Sepsis

It is your body’s extreme response or reaction to an infection. In sepsis, an ongoing infection in your body triggers a chain reaction in several organs, leading to organ damage and even death.

Cancers

Like lymphoma, leukaemia, and myeloma impact your immune system directly. These cancer cells come from immune system cells that grow out of control. The cancer cells don’t do anything useful and cause damage.

Medications

Like corticosteroids depress or weaken your immune system. They decrease inflammation in your body but leave you vulnerable to subsequent infection, especially when taken for long periods. Immunosuppressant drugs keep the immune system from attacking a transplanted organ and rejecting it after an organ transplant. Unfortunately, these medications also increase the risk of catching an infection.

Autoimmune Disorders

A few times, your immune system erroneously thinks that your cells are foreign substances and attacks them. This type of response is called an autoimmune response, and the resulting disease is termed an autoimmune disorder. There are currently more than 80 known autoimmune disorders. Examples include diabetes mellitus type 1, systemic lupus erythematosus, and rheumatoid arthritis.

Allergies

Who’s not familiar with allergies? An allergy is a reaction to a substance your body thinks is an invader. The reaction may be to pollen, pet dander, or food that doesn’t normally cause a reaction in most people.

PIDD

Or primary immunodeficiency diseases are secondary to genetic changes and are usually inherited (run in families). This is a large group of more than 100 immunodeficiency diseases. All of them basically keep your immune system from working correctly in one way or another.

Alcoholism and alcohol abuse

Chronic heavy alcohol consumption is linked to decreased numbers of lymphocytes (both B-cells and T-cells) and increased susceptibility to both viral and bacterial infections. The exact process of how this happens is still unknown.

Heat Stress, heat stroke, and heat exhaustion

People who engage in strenuous physical activities or work under the sun for too long can experience inflammation throughout the body that leads to immune dysfunction. Like alcoholism, heat stress can increase susceptibility to infections.

HOW TO KEEP YOUR IMMUNE SYSTEM HEALTHY

Cover the basics

It doesn’t get any more straightforward than this. Positive lifestyle changes can undoubtedly boost your immune system. The following are the bare minimum measures you can take to support a healthy immune system:

1. Maintain a healthy body weightthrough diet and regular exercise. Also, assess your nutritional status.
2. Stop smoking and limit your alcohol intake.
3. Learn to handle and relieve stress.
4. Get sufficient rest and sleep.
5. Stay up to date with your vaccinations.
6. Keep your surroundings clean, and wash your hands often.

Immune boosters

You may have heard or read the term immune booster on supplements. Immune boosters are nutritional supplements that provide raw material and substrates to your immune system. They don’t literally boost your body’s immune response to any disease. Supplements that are immune boosters may contain a unique formula or cocktail of immune-boosting nutrients. Experts like a qualified naturopath or a doctor specialising in functional medicine can tailor these formulas to your specific needs. Below are some essential immune-boosting nutrients:

1. Minerals like zinc, iron, and magnesium. Zinc , particularly in syrup or lozenge form, is effective in keeping the rhinovirus (the cause of the common cold) from multiplying in the nasal airways and throat during a cold, according to a 2017 research study. It’s most helpful, especially when taken within 24 hours from the start of the cold. Zinc is vital for the normal function of cells responsible for regulating innate immunity like natural killer cells, macrophages, and neutrophils. If you have a zinc deficiency, the optimal functioning of these cells will be affected. Iron is strictly controlled in your body. A minor disturbance in iron balance can affect both adaptive and innate immunity. In adaptive immunity, iron influences antibody production by B-cells and activation of T-cells. Concerning innate immunity, iron also helps regulate the activities of natural killer cells, neutrophils, and macrophages, similar to zinc. Magnesium deficiency or hypomagnesemia had been associated with an increased risk of developing some types of cancers, according to a 2022 research study from the University of Basel, Switzerland. T-cells are members of the adaptive immune system that target and eliminate cancer cells. They need an adequate amount of magnesium to work correctly. The study found that among cancer patients, immunotherapy (a form of cancer treatment) was less effective among patients with less-than-ideal blood levels of magnesium.
2. Vitamins A, C, D, and E. Vitamin A is required for the regeneration of mucus membranes (after being damaged by an infection) and optimal functioning of B-cells and T-cells. Vitamin C has a long and controversial reputation for helping the immune system prevent and treat upper respiratory tract infections (e.g., the common cold) among the general population. This is not the case for people who have stressful jobs. They benefit the most from vitamin C supplementation to prevent infections.Vitamin D modulates the innate and adaptive immune response. It adjusts the magnitude of the response to appropriate levels for the disease-causing microorganism. It’s a fact that almost all cells of your immune system have a receptor for vitamin D, signifying a solid connection between them. People with darker skin, the elderly, immunocompromised, and those who live in cold climates with less sunshine duration are at risk of developing vitamin D deficiency. Vitamin E is a potent antioxidant and is effective in minimising age-related immune dysfunction. The older you get, the more your immune system benefits from vitamin E supplementation due to its ability to prevent cell damage. This is handy, especially during an intense immune response where reactive oxygen species are generated. Note: A deficiency in any of these vitamins and minerals can weaken your immune system and make you more susceptible to infections. Click on the attached links to each vitamin or mineral to know more about it.
3. NAC or N-acetyl-L-cysteine, as a medication, is used to cure paracetamol overdose and loosen mucus in people with respiratory conditions. In experimental conditions, it has been shown that NAC has good antibacterial properties and can disrupt biofilm formation under controlled conditions. Biofilms are layers of disease-causing microorganisms that adhere to wet surfaces and cause several infections.
4. Carotenoids such as curcumin, β-carotene, lutein, lycopene, and zeaxanthin have antioxidant properties and various immunological functions. Some of these functions include stimulating the bacteria-killing ability of macrophages and neutrophils, increasing the population of specific immune cells, and increasing the production of cytokines (e.g., growth factors).
5. Bioflavonoids have potent anti-inflammatory and antioxidant properties that help maintain the immune system's function. They also enhance the absorption of vitamin C and its utilisation in the body.
6. β-glucans behave as immunomodulating agents that directly bind and activate cells of innate immunity. They’re made up of glucose molecules and are regular cell wall components of cereals (e.g., barley, oats), mushrooms (shiitake, reishi), seaweed, and yeasts.
7. Reishi mushroom is usually taken as an extract in the form of a capsule, powder, or liquid. Some molecules in this mushroom can magnify the activity of natural killer cells, which are noted for fighting off infections and cancer cells.
8. Shitake (or shiitake) mushrooms are well-recognised for their rich taste and flavour. Like reishi mushrooms, they’re also available as supplements. Experiments under controlled conditions have shown that a polysaccharide (carbohydrate) derived from these mushrooms may enhance mucosal and systemic immunity on a genetic level. More studies are warranted to document these findings in vivo (under living conditions).
9. Elderberries are the dark purple berries from the European elder tree. It has traditionally been used as medicine for the cold and flu. Elderberry and its extracts are rich in bioactive compounds like anthocyanins and quercetin. These compounds contribute to the decrease in the severity of symptoms and shorten the duration of upper respiratory tract infections like the common cold and flu.

Your immune system is comprised of two interrelated systems, the innate and adaptive immune systems. Whenever there’s a threat from a foreign substance or infection, your innate immune system is the first to respond and contain the threat. It’s quick, and the response is always the same. The adaptive immune system is the second line of defence and tailor-made (specific) to the disease-causing microorganism or harmful substance. Its effect is long-lasting. Depending on the present status of your health and nutrition, immune-boosting supplements can help your body stay healthy and fight off infections. Finding the right formula or mixture of ingredients in a supplement can address deficiencies you may not be aware of. And, of course, before you take any immune-boosting supplement, it’s always best to talk to your doctor first, especially if you have a medical condition.