Immunoglobulins 101

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The Pure TheraPro Team

The Pure TheraPro Education Team is comprised of researchers from diverse backgrounds including nutrition, functional medicine, fitness, supplement formulation & food science. All articles have been reviewed for content, accuracy, and compliance by a holistic integrative nutritionist certified by an accredited institution.
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Immunoglobulins, commonly known as antibodies, constitute a fundamental component of your immune system, serving as crucial defenders against a broad spectrum of pathogens. Their existence is essential for identifying, neutralizing, and eliminating harmful invaders, including bacteria, viruses, and toxins. In this article, we’ll delve deep into the world of immunoglobulins, exploring their structure, and vital functions.

Immunoglobulin Structure

Immunoglobulins are like special proteins in our bodies that help protect us from harmful things like germs. They have a shape that looks like the letter Y, and they're made up of four parts: two heavy parts and two light parts. These parts are connected together in a way that allows them to move and bend.

What makes these proteins even more interesting is that there are two types of light parts: one called kappa and the other called lambda. These proteins also have two important regions: one that helps them recognize bad things called antigens, and another that decides what they do to fight these bad things.

Your body make these special proteins in your bone marrow, where cells called B cells grow and change. They do a kind of mixing and matching with their genes to create unique parts of the immunoglobulin proteins, so they can recognize many different bad things (pathogens and antigens).

When these proteins encounter the bad things, they change into another type of cell called plasma cells, which are like factories that produce a lot of these proteins. These proteins then go into our blood and other bodily fluids to help our immune system stay strong and ready to fight off infections.

So, these immunoglobulins are essential for our immune system to work well, and they're always being made and sent out to keep us healthy.

Immunoglobulin Functions

Immunoglobulins execute multifaceted roles, collectively contributing to your immune system’s vigor and prowess:

  • Antibody-Mediated Immunity: Immunoglobulins tag pathogens for destruction by immune cells.
  • Neutralization of Pathogens: Antibodies neutralize viruses and toxins, preventing them from causing harm.
  • Opsonization: These molecules facilitate the engulfment of pathogens by phagocytic cells.
  • Complement Activation: Some antibodies activate the complement system, which leads to the elimination of pathogens.

In addition to their immediate protective functions, immunoglobulins play a crucial role in immune memory. This ensures that subsequent encounters with the same pathogen result in a quicker and more effective immune response.

Immunoglobulin Diversity

Immunoglobulin diversity stands as a testament to the remarkable adaptability of the immune system. Within our bodies, various mechanisms play out to create an extensive collection of antibodies, each designed to recognize a unique array of pathogens.

Immunoglobulin receptors are the watchful guardians of our immune response, ever vigilant in their duty to identify and respond to potential threats. There are three major types of immunoglobulin receptors, each with a distinct role in orchestrating our immune defense.

  1. Fc Receptors (FcRs) adorn the surfaces of immune cells such as macrophages, neutrophils, and natural killer cells (NK cells). These receptors have a special affinity for the constant (Fc) region of antibodies, enhancing the immune system’s ability to respond to antibody-bound pathogens. They act like molecular beacons, signaling the presence of invaders to the immune troops.
  2. B-Cell Receptors (BCRs), interestingly, are possessed by the B cells themselves. These receptors bear a structural resemblance to antibodies and play a pivotal role in initiating immune responses when they encounter antigens. It’s almost as if B cells are equipped with their own sensory devices, allowing them to sound the alarm when a threat is detected.
  3.  T-Cell Receptors (TCRs), while not antibodies, are indispensable for the immune response. T cells have specialized receptors called TCRs, which recognize antigens presented on the surface of infected or abnormal cells. These receptors initiate a cellular immune response, akin to special ops forces targeting enemy strongholds.

 The Five Classes of Immunoglobulins: Diversity in Immune Function

There are five main classes of immunoglobulins, each with unique properties and functions. These classes are IgM, IgG, IgA, IgD, and IgE:

  1. IgM (Immunoglobulin M): IgM is the first antibody produced in response to an infection. It is often associated with the initial stages of an immune response. IgM antibodies are large and pentameric, consisting of five antibody subunits. This structure allows them to efficiently trap pathogens in your bloodstream and activate complement proteins, aiding in the destruction of pathogens. IgM antibodies are particularly effective against bacteria and viruses. They serve as vital tools in the early stages of immune defense.
  2. IgG (Immunoglobulin G): IgG created by your body is the most abundant class of antibodies in the bloodstream, constituting approximately 75-80% of all antibodies. It is a versatile antibody class that provides long-lasting immunity support. IgG antibodies created by your body are responsible for neutralizing toxins and viruses, opsonizing (marking for destruction) bacteria, and crossing the placenta to extend passive immunity to newborns. They are also the primary antibodies produced during secondary immune responses, providing a robust and rapid defense against previously encountered pathogens.
  3. IgA (Immunoglobulin A): IgA is predominantly found in mucosal surfaces, such as the lining of the respiratory and gastrointestinal tracts, as well as in saliva, tears, and breast milk. It serves as the first line of defense against pathogens attempting to enter the body through these mucosal membranes. IgA antibodies are often present as dimers, joined by a protein called the secretory component, which enhances their stability in mucosal secretions. These antibodies work to prevent the attachment of pathogens to mucosal surfaces and inhibit their invasion.
  4. IgD (Immunoglobulin D): IgD is relatively less understood than other antibody classes, and its precise function remains a subject of ongoing research. It is primarily found on the surface of mature B cells, where it acts as a receptor for antigens. IgD may play a role in regulating B cell activation and differentiation. Although it is less abundant in circulation, IgD is essential for the activation of B cells and their involvement in adaptive immune responses.
  5. IgE (Immunoglobulin E): IgE antibodies are best known for their role in allergic reactions and immunity against parasites. When the immune system encounters an allergen, such as pollen or certain foods, it produces IgE antibodies. These antibodies bind to receptors on mast cells and basophils. Upon re-exposure to the allergen, IgE antibodies trigger the release of histamine and other chemicals, leading to allergic symptoms. Additionally, IgE plays a role in defense against parasitic infections by activating immune responses that expel parasites from the body.

These five classes of immunoglobulins work collaboratively to provide a multifaceted defense against a wide range of pathogens. Their diversity in structure and function ensures that our immune system can mount effective responses tailored to the nature of any threat, whether it be bacterial, viral, parasitic, or allergenic.

Associated Diseases:

Immunoglobulins occupy a central role in the intricate balance of the immune system, both in maintaining health and contributing to various diseases when this balance is disrupted. Primary immunodeficiencies are the result of genetic mutations that can lead to deficiencies in immunoglobulin production or function. Individuals with these conditions are more vulnerable to infections, highlighting the essential role of immunoglobulins in our defense against pathogens.

Autoimmune diseases, on the other hand, occur when the immune system turns against your body’s own tissues. This can happen when immunoglobulins and immune cells mistakenly target self-antigens, leading to autoimmune disorders such as rheumatoid arthritis, lupus, and multiple sclerosis. In these conditions, the immune system’s precision becomes a double-edged sword.

Low levels of immunoglobulins, particularly immunoglobulin G (IgG) and immunoglobulin A (IgA), can lead to an increased susceptibility to various infections and medical conditions. Here are some diseases and conditions associated with low levels of immunoglobulins:

  • Common Variable Immunodeficiency (CVID): CVID is a primary immunodeficiency disorder characterized by low levels of IgG and IgA, which can result in recurrent infections, particularly of the respiratory and gastrointestinal tracts.
  • Recurrent Respiratory Tract Infections: Low levels of immunoglobulins, especially IgA and IgG, can make individuals more prone to frequent respiratory infections such as pneumonia, bronchitis, and sinusitis.
  • Selective IgA Deficiency: Individuals with selective IgA deficiency have a decreased level or absence of IgA, which can lead to recurrent respiratory and gastrointestinal infections. They may also be at risk for autoimmune diseases.
  • Hypogammaglobulinemia: Hypogammaglobulinemia is a condition characterized by low levels of immunoglobulins, increasing susceptibility to various bacterial and viral infections.
  • Chronic Sinusitis and Ear Infections: Individuals with low levels of immunoglobulins may experience chronic sinusitis and ear infections due to their compromised immune response.
  • Gastrointestinal Infections: Low IgA levels can make individuals more susceptible to gastrointestinal infections and conditions, including chronic diarrhea and malabsorption syndromes.
  • Autoimmune Diseases: While low immunoglobulin levels are more often associated with immunodeficiency, some autoimmune diseases, like systemic lupus erythematosus (SLE), can result in decreased levels of certain immunoglobulins.

It's essential to note that low immunoglobulin levels can be congenital (present from birth) or acquired due to various underlying medical conditions or treatments. Treatment options may include immunoglobulin replacement therapy (IVIG) to help boost the immune system's defenses in individuals with immunoglobulin deficiencies. 

Tips to Improve Immunoglobulin Levels

Improving immunoglobulin levels can help enhance your immune system's ability to defend against infections and maintain overall health. Here are five tips, including the use of supplementation, to boost immunoglobulin levels:

Balanced Diet and Supplementation: Proper nutrition is essential for a healthy immune system. Consume a well-balanced diet rich in vitamins and minerals, especially those that support immune function. Focus on foods like fruits, vegetables, lean proteins, gluten-free whole grains, and healthy fats. Vitamins and minerals such as Liposomal Vitamin C, Lipsomal Vitamin D3, chelated Zinc, and the antioxidant mineral Selenium are particularly important for immune health.

Pure Thera’s Elite IgG™ is a best-in-class, serum-derived immunoglobulin powder clinically proven to support robust immune function and optimal digestive wellness. It works in your body by binding inflammatory, potentially toxic antigens within your digestive tract and prohibiting them from crossing the gut barrier. This has tremendous implications in supporting the restoration of a healthy inflammatory balance, a normal bowel pattern and stool consistency, and helping to reverse and repair “leaky gut”.

Elite IgG formulated with ImmunoLin® is lactose-free. Colostrum, on the other hand, is a milk-based compound, thus products containing it include elevated levels of lactose (a sugar that is often poorly tolerated, resulting in GI distress for many of us). Elite IgG contains no lactose since it is derived from serum & not milk. Laboratory tests show that ImmunoLin® IgG immunoglobulins provide the highest percentage of immunoglobulins available compared to other commercially available colostrum supplements.

Available in capsules and powder,  Elite IgG provides powerful serum proteins, 18 crucial amino acids and rare growth factors that are essential for optimal vitality. Unlike inflammatory cow’s milk-based colostrum and IgG products, Elite IgG is sourced only from patented, pharmaceutical-grade ImmunoLin Bovine Immunoglobulin Isolate.

Each serving of Elite IgG provides over 1,000 mg of Immunoglobulin G and is completely free from dairy, GMOs, sugar and antibiotics.

Regular Exercise: Engaging in regular physical activity can help improve immune function. Exercise promotes better circulation, reduces inflammation, and enhances overall immune system performance. Aim for at least 150 minutes of moderate-intensity aerobic exercise per week, along with strength training exercises.

Adequate Sleep: Quality sleep is crucial for immune function and the production of immunoglobulins. Aim for 7-9 hours of restorative sleep each night to support your body's immune system. Create a sleep-conducive environment, establish a regular sleep schedule, and limit exposure to screens before bedtime.

Stress Management: Chronic stress can weaken the immune system, including reducing immunoglobulin levels. Practice stress-reduction techniques such as mindfulness meditation, deep breathing exercises, yoga, or spending time in nature. Engaging in activities you enjoy can also help reduce stress.


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