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Immune Resilience – Keep Your Patients Healthy during the Cold & Flu Season

Immune Resilience – Keep Your Patients Healthy during the Cold & Flu Season
Happy friends talking with coffee mugs in a park
By DiagnosTechs News September 28, 2023

We are now just beginning the cold & flu season, and it is crucial to support the health of the immune system this time of year. The cold & flu season has been an annual phenomenon for centuries. Hippocrates, the father of medicine, noted the seasonal nature of highly infectious respiratory diseases in the “Book of Epidemics” in 400 BC.1

In modern times, the estimated costs for the common cold in the US are $40 billion per year. Influenza costs are an astounding $87 billion each year in the US, which highlights the colossal scope of the cold & flu season.1

Two of the newest viruses, SARS-CoV and SARS-CoV-2, emerged during the winter months since the winter environment promotes the spread of several respiratory viral infections. Human respiratory syncytial virus (RSV), influenza, and human coronaviruses are some of the most common underlying causes of seasonal respiratory tract infections.1 Continue reading below to learn more about the natural shield against viruses – Secretory IgA!

The Mucosal Immune System

The moist tissues that line the nasal passages, sinuses, mouth, and throat are known as mucosal surfaces. Since these surfaces are exposed to the outside world, they have a robust mucosal immune system to protect them. Every time you take a breath, your airways are exposed to innumerable and invisible toxins, allergens, and pathogens. If mucosal immunity is not optimal, respiratory viruses can quickly invade the body, causing infection and dysfunction.2

One of the first lines of defense against viruses is an extraordinary and specialized antibody known as Secretory IgA (sIgA) that is naturally produced by the mucosal immune system.

What is Secretory IgA (sIgA)?

Secretory Immunoglobulin A, also known as Secretory IgA or sIgA, is a specialized antibody that can function outside the body on mucosal surfaces. IgA was first discovered in 1953 and is the most abundant immunoglobulin produced along the mucosal surfaces.3 Studies show approximately 74% of all mucosal antibodies are IgA antibodies.2

Immunoglobulin A (IgA) is one antibody isotype produced by the immune system. Other antibody isotypes include IgG, IgD, IgE, and IgM. To produce secretory IgA, two IgA molecules are linked together along with a secretory component. More IgA antibodies are produced daily than the total amount of all other antibody isotypes combined.2 Here is a picture of the structure of the different isotypes of antibodies:

Secretory IgA is considered a protective and anti-inflammatory antibody, while other antibodies primarily have an inflammatory effect. For example, when an IgG antibody interacts with a pathogen, it has the ability to kill it, which sounds beneficial, but this process can cause a high level of inflammation that damages cells and tissues.4 Secretory IgA antibodies prevent infections by other mechanisms that minimize inflammation and damage.

Because of its unique immunosuppressive and immunomodulatory capabilities, sIgA helps to maintain homeostasis at the mucosal barrier. Maintaining a balance in inflammatory and anti-inflammatory activity is a challenge since the mucosal surfaces are permanently exposed to an enormous variety of both harmful and harmless organisms, compounds, and molecules. More research has been performed on the protective activities of sIgA in the gut than in the airways. However, similar mechanisms are likely to occur in the respiratory mucosal tissues to maintain health during the cold & flu season.5

How does sIgA offer Protection from Cold & Flu Viruses?

Technically, sIgA begins to protect health in infancy since it is the predominant immunoglobulin present in breastmilk. In infants, sIgA in natural breast milk protects against acute infections but also supports lifelong health. Research shows a lack of sIgA in early life due to being formula-fed rather than breastfed may increase the risk of developing inflammatory bowel disease (IBD), obesity, allergies, and autoimmune disorders, including asthma.3

Secretory IgA and the mucosal immune system also play a starring role during every cold and flu season. The total surface area of the respiratory and digestive tracts is approximately 200 times larger than that of the skin. Approximately 60–70% of white blood cells reside in the mucosal tissues to protect them since the mucosal surfaces are incessantly exposed to microorganisms, allergens, and toxins from the outside world.4 Secretory IgA binds to the mucus layer that covers and protects the mucosal surfaces.5

In the gut, research shows sIgA protects the mucosal tissues in at least three different ways:

  • Secretory IgA neutralizes pathogens, including viruses
  • Secretory IgA develops the composition of the beneficial commensal microbiota
  • Secretory IgA prevents harmful inflammatory responses to pathogens, foods, and other substances that interact with the mucosal surfaces.5

When present in mucosal secretions, sIgA molecules bind to infectious pathogens, thus preventing their adhesion and entrance into the body. The binding of sIgA molecules to these pathogens then facilitates their elimination. Preventing the adhesion and adsorption of pathogenic organisms while also facilitating their removal is a phenomenon known as “immune exclusion.” Two additional methods by which sIgA molecules reduce the likelihood of viral infections include direct interference with surface receptor binding and a reduction in the activation and expression of pathogenic virulence factors.6

So, sIgA is able to eliminate viruses (and other pathogens) via immune exclusion before they enter the body and neutralize intracellular viruses.5

Evidence that Supporting sIgA Production is Beneficial during the Cold & Flu Season

Research shows active infection with cold & flu viruses, including influenza, rhinovirus, and coronavirus, elicits an increase in sIgA production along the nasal mucosae. Also, animal studies have demonstrated that nasal sIgA directly protects against infection with influenza.5

Evidence from studying endurance athletes also supports the powerful role sIgA plays in preventing upper respiratory viral infections. Research shows strenuous exercise, a stressor, decreases sIgA production, which then leads to increased upper respiratory viral infections in elite athletes.5

Selective IgA Deficiency (SIgAD) is a genetic condition characterized by an inability to produce IgA and sIgA. Since individuals with SIgAD cannot produce sIgA, they offer an opportunity to assess the effects of low sIgA production. Epidemiological studies show recurrent infections of the respiratory system are the most common finding in patients with SIgAD. Not all patients with SIgAD experience increased infections, though. Researchers speculate that some of these patients have increased production of sIgM antibodies to adapt to the absence of sIgA.5

Are you and your patients adequately protected in preparation for this cold & flu season? Have you tested your sIgA level?

Secretory IgA (sIgA) Testing

Secretory IgA (sIgA) is a measurable biomarker that reflects the resilience of the mucosal immune response. Secretory IgA is synthesized by activated B cells along the mucosal membranes in the mouth, sinuses, eyes, throat, lungs, gastrointestinal tract, and genitourinary tract. Since these mucosal surfaces are exposed to the outside world, sIgA is considered to be an important part of the first line of immune defense against the pathogens that cause infections – including cold & flu viruses.6

The total salivary sIgA level generally mirrors the sIgA level in other mucosal tissues (e.g., lungs) and is an expedient tool to monitor changes in mucosal immune status.6 Intestinal sIgA directly assesses sIgA production in the GI tract. Get your patients ready for the cold & flu season by testing and optimizing their sIgA level.

Treatment Options to Boost sIgA Production

Evidence shows these supportive options help maintain the optimal production of sIgA*:

  • Probiotics7-9
  • Prebiotics21-24
  • Colostrum25,26
  • Thymus glandular27
  • Nutritional Immune support
  • Herbal Immune Support
    • Turmeric36,37
    • Medicinal mushrooms36,38-42
    • Astragalus41,43
    • Echinacea44
    • Ginseng45
    • Shosaiko-to46
    • Fucoidan47
    • Chlorella48,49
    • Aloe vera gel50
    • Elderberry9
  • Stress Management51-54
    • Adaptogens such as Ginseng, Ashwagandha, and Eleuthero45,46,55,56
    • GABA57,58
    • Glycine59
    • Passiflora spp.60,61
    • Meditation62,63
    • Therapy/companion dog64
    • Forest bathing65
    • Biofeedback66
    • Expression of anger67
    • Participation in musical activity68
    • Listening to music69,70
    • Daily relaxation routine71
  • Amino Acids
    • N-acetylcysteine72
    • Glutamine73,74
    • Arginine75-77
    • L-tryptophan78
    • Leucine79
    • Taurine80
  • Exercise
    • Regular moderate aerobic exercise81,82
    • Resistance training83,84
  • Acupuncture85,86
  • Optimize blood glucose management and HbA1c level87
  • Pre-germinated brown rice88
  • Intermittent fasting89

 

Total Salivary Secretory IgA (sIgA) can be ordered as part of an:

Total Intestinal Secretory IgA (sIgA) can be ordered as part of a:

Total Intestinal sIgA and Total Salivary sIgA can also be ordered as single tests.

To place a test order, click here. As a reminder, DiagnosTechs will drop ship test kits directly to your patients. You may select this option at the top of the order form.

Please visit our Provider Tools page for more information about choosing the right test and mucosal immunity.

* This statement has not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure or prevent any disease.

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NATURAL IMMUNE SUPPORT FOR THE COLD AND FLU SEASON

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