Immunoglobulins: Optimizing Immune and Digestive Function

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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 are glycoproteins that maintain your immune system by binding to unwanted pathogens and potentially inflammatory antigens. Immunoglobulins support a healthy digestive system and immune function by breaking a pro-inflammatory cycle that can lead to digestive dysfunction and poor health.

So where can you find Immunoglobulins and how do you get more of them? While colostrum supplements and lactoferrin supplements are arguably the most popular way, they are not the best choice for most people. This is because colostrum supplements and lactoferrin supplements:

  • Must be derived from cow’s milk 
  • Usually full of poorly tolerated lactose 
  • Contain inflammatory milk proteins such as whey and casein 
  • Often rife with other toxins such as lipopolysaccharides (LPS), antibiotic and growth hormone residues

    Serum-derived bovine immunoglobulin supplements (IgG supplements) on the other hand, such as Pure TheraPro Rx®’s Elite IgG™, are not derived from milk, rather they are derived from bovine serum, making them safer, better tolerated and more effective than colostrum and lactoferrin supplements. 

    Read on to discover why serum-based immunoglobulin supplements  (IgG Supplements) can be an absolute game changer for those wishing to overcome gut health challenges and support optimized immune function. 

    What are Immunoglobulins?

    When they were discovered in 1890 by immunologists, immunoglobulins were initially called “neutralizing substances.” Immunoglobulins, or antibodies, are special types of glycoproteins that maintain and optimize your body’s immune system. Traditionally they are released by your immune cells to fight off unwanted pathogens and are varied in their type and function in your body. 

    Often found in liquid secretions of the body including: breast milk, tears, saliva, gastric juices, and in protective mucus that lines internal body cavities, there are five types or classes of these molecules - IgG, IgM, IgA, IgD, and IgE. They are classified based on their function, structure, and location in your body. 

    IgG is the most common and plentiful immunoglobulin in your body, about 80% of immunoglobulins in your body are the IgG (Immunoglobulin-G) form – IgG can: 

    • Provide immunity to babies through breast milk
    • Neutralize unwanted pathogens
    • Remembering what germs you have been exposed to in the past
    • With exposure to these germs again, your body knows exactly how to attack them based on IgG ‘memory’

    IgA immunoglobulins make up about 10-15% of the immunoglobulins present.These molecules are present in areas with mucous membranes including in your nose, breathing passages, digestive tract, eyes, saliva, and tears, protecting body surfaces that are exposed to outside foreign substances. 

    IgM immunoglobulins are found in your blood and lymphatic fluid. They are the first line of defense against any unwanted pathogens. When you come in contact with a germ, IgM is the first level of immunoglobulin to rise in your body. 

    IgE immunoglobulins are found in your lungs, skin, and mucous membranes. Often these immunoglobulins are created in large amounts when your immune system overreacts to things that aren’t harmful like pollen or dust. These immunoglobulins are found in high levels in people with allergies and can be involved in allergic reactions to certain foods like milk or peanuts and medications. 

    IgD immunoglobulins are found in small amounts in your stomach and chest, experts are unsure how these particular immunoglobulins function. (1) 

    Digestive Function and Immunoglobulins

    There is a common cycle in the body that often goes like this: something foreign enters your digestive system and triggers an overreaction within your gut. This trigger leads to changes in the lining of your intestine, an increased inflammatory response from your immune system and subsequent gut barrier dysfunction or “leaky gut” syndrome. These foreign substances leak out of your gut and travel throughout your body, inciting a greater inflammatory response on a systemic level, this can occur over and over again and can lead to unwanted health problems. By using IgG, IgM, and IgA immunoglobulins supplements, you can break this cycle. Immunoglobulins bind to unwanted substances and discourage them from impacting your gut and/or whole body.

    Dietary Supplement Solutions to Digestive Dysfunction 

    Many dietary supplements utilize bovine colostrum (the milk produced by a mother cow immediately after the birth of a calf) as a source of these beneficial immunoglobulins. Colostrum contains high levels of immunoglobulins and other immune supportive factors like lactoferrin (found readily in lactoferrin supplements) as well as other peptides important for nutrition (2,3). Since colostrum contains a high concentration of immunoglobulins, it is often used in dietary supplements to support immune and digestive health. There are some significant drawbacks to colostrum, however, which we’ll detail below. A superior source of immunoglobulins is serum-derived bovine immunoglobulins or SBI. Even the best lactoferrin supplement or colostrum supplement cannot meet the potency, purity and efficacy standards set by SBI.

    Colostrum vs. Serum Derived Bovine Immunoglobulin 

    The Pure TheraPro Rx® Difference: ImmunoLin® 

    Pure TheraPro Rx® chose ImmunoLin® over any other immunoglobulin source for many reasons including: 

    • ImmunoLin® contains over 50% immunoglobulins
    • Dairy & Lactose free 
    • Clinically studied for its superior ability to support healthy digestive function, gastrointestinal lining strength, immune response, and nutritional status 
    • Created in an FDA inspected facility using the highest quality ingredients and manufacturing standards

    Colostrum (often found as a stand-alone colostrum supplement) is a milk-based product and almost always contains lactose, which is poorly tolerated by most people. The gene that controls production of lactase, the enzyme responsible for breaking down lactose, should be turned on after birth and off after breastfeeding. Often this normal and common lactose intolerance causes digestive discomfort and can result in decreased absorption of nutrients. Elite IgG™’s ImmunoLin®, on the other hand, contains no lactose since it is derived from serum and not cow’s milk or colostrum.

    Let’s look at a few other benefits that serum-derived immunoglobulin supplements have over dairy-sourced immunoglobulins:

    • Provides a higher concentration of immunoglobulins as compared to colostrum. In fact, ImmunoLin® provides the highest percentage of immunoglobulins, specifically IgG per gram. This higher concentration of immunoglobulins makes ImmunoLin® a more potent source of these immune supportive substances.
    • When processing bovine colostrum, there are many other variables that come into play including the health of the cow, composition of the milk, and more. Often the colostrum harvesting process exposes the end product to LPS. If bovine colostrum is collected when a cow is sick, the milk product may be high in pro-inflammatory LPS molecules. Additionally, proper storage of colostrum, once collected, is key to maintaining its ability to support digestive and immune function (4). 
    • Contains extremely low levels of LPS as compared to colostrum supplements. These naturally pro-inflammatory molecules can inflame your intestinal mucosa increasing gut permeability and gastrointestinal distress. Higher concentrations of LPS in colostrum can exacerbate digestive issues, lower LPS levels in serum-derived bovine immunoglobulin supplements make them a much purer alternative to colostrum supplements. Often this exposure to LPS cannot be purified away during processing. 
    • More stable than colostrum. The ImmunoLin® found in Elite IgG™ is manufactured in a cGMP facility using rigorous, isolation purification and filtration methods and precautions and procedures to ensure the safety, cleanliness, stability and consistency of each batch of SBI. 
    • Serum-derived bovine immunoglobulin supplement contains transferrin, cytokines, and albumin protein. Transferrin is an iron binding protein that can bind unwanted pathogens and supports a healthy inflammatory response. Cytokines are small proteins that allow communication between immune cells. If this communication is disrupted, this can lead to an increased inflammatory response. Albumin is one of the most abundant proteins found in your body. These key proteins help to maintain fluid balance in your body, support healthy hormone levels, and aid in the transportation of nutrients.

    Pure TheraPro Rx’s Elite IgG 

    Pure TheraPro Rx®’s Elite IgG™ ImmunoLin® SBI immunoglobulin supplement offers many benefits to digestive and immune health. Pure TheraPro Rx® Elite IgG™ harnesses the power of serum-derived bovine immunoglobulins. Providing clinically proven support for robust immune function and optimal digestive wellness. This supplement supports the restoration of a healthy inflammatory balance, a normal bowel pattern and stool consistency, and helps to reverse and repair “leaky gut”. Elite IgG™ also 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 lactoferrin supplements, Elite IgG™ is sourced only from patented, pharmaceutical-grade ImmunoLin® Bovine Immunoglobulin Isolate. Each serving provides over 1,000 mg of Immunoglobulins and is completely free from dairy, GMOs, sugar and antibiotics.


    1. Justiz Vaillant AA, Jamal Z, Ramphul K. Immunoglobulin. [Updated 2022 Jan 24]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from:
    2. Godhia ML, N. P. Colostrum - Its Composition, Benefits As A Nutraceutical : A Review. Current Research in Nutrition and Food Science. 2013;1(1):37-47.
    3. Hurley WL, Theil PK. Perspectives on immunoglobulins in colostrum and milk. Nutrients. 2011;3(4):442-474. doi:10.3390/nu3040442
    4. Kaplan M, Arslan A, Duman H, et al. Production of Bovine Colostrum for Human Consumption to Improve Health. Front Pharmacol. 2022;12:796824. Published 2022 Jan 3. doi:10.3389/fphar.2021.796824


    Author bio: 

    Melissa Anzelone, ND, has worked in the naturopathic field for 11 years and trained under Drs. Ashley Lewin, Peter D’Adamo, and David Brady. She exemplifies her passion for natural health by helping clients balance hormones, intervene in metabolic disease, and promote weight loss using the most gentle modalities first.