Measuring sIgA can give us insights into a patient’s oxidative stress stemming from gut dysbiosis.
Secretory Immunoglobulin A (sIgA) is a crucial component of the immune system, particularly in mucosal immunity. It is the most abundant immunoglobulin found in mucosal secretions, including saliva, tears, and secretions from the respiratory and gastrointestinal tracts. In functional medicine, sIgA is considered a key marker for assessing mucosal immunity and overall immune function. It helps in understanding the body’s first line of defense against infections and its ability to maintain mucosal integrity. sIgA’s role in immune exclusion, where it traps pathogens and facilitates their removal, is essential for preventing infections and maintaining a balanced immune response.
sIgA is particularly important in the gut, where it helps maintain the balance of the gut microbiota and protects against pathogenic bacteria. Low levels of sIgA in the gut can indicate a compromised mucosal barrier, which may lead to increased susceptibility to infections, inflammation, and conditions like leaky gut syndrome. Testing sIgA levels can help identify these issues early, allowing for targeted interventions to restore gut health.
Oxidative stress occurs when there is an imbalance between the production of reactive oxygen species (ROS) and the body’s ability to neutralize them. This imbalance can lead to cellular damage and inflammation. The gut microbiota plays a significant role in regulating oxidative stress by producing metabolites that influence the REDOX balance. Dysbiosis, or an imbalance in the gut microbiota, can disrupt this balance and contribute to oxidative stress. Measuring sIgA levels can provide insights into the state of the gut microbiota and its ability to manage oxidative stress, helping to identify potential areas of intervention.
Originally it was thought that sIgA was merely a barrier. An important barrier, one that comprises 80-90% of our overall immune function. sIgA lines any area of the body that interfaces with the outside world. It does not merely function as a barrier, but also as the first touchpoint for ongoing immune conversations, not just locally but systemically as well.
sIgA circulates into immune cells that line the gut, or GALT. Peyer’s patches, part of this network, receive queues from the relative amount of sIgA that is present. When sIgA goes down, this changes how the systemic immune system responds. For example, lower levels of sIgA will cause more immune confusion, resulting in higher IgG titers to foods. Even when the food is removed, if the body’s first-line defense is down (sIgA), titers will remain higher for a longer period of time as the body works to compensate for its normal, first-line immune support being compromised. This has particular relevance for elimination diets prescribed for those who test positive for food allergies and sensitivities, and it’s why it makes sense to run our new Gut-Ox Stress Test at the same time as our P88-DIY DAT test- especially since samples for both tests can be collected by the patient themselves, no phlebotomist required.
Also, when sIgA is low, the body begins to treat commensal organisms as pathogens. The body realizes that immune support is down, and becomes more reactive, assuming that maybe even a commensal organism is now the reason for decreased level of sIgA. Remaining immune cells will create more oxidative stress in response to commensal pathogens and the body can get worse from the immune system being overly activated to commensal organisms and through immune confusion to foods or other environmental allergens.
sIgA also works to trap pathogens, and flush them downstream, and out of the body. Without sIgA, a pathogen is not only less likely to be trapped but also less likely to be moved out of the body.
sIgA also communicates with dendric cells helping them to be primed and commit to an identity. Exhaustion of sIgA will cause dendritic cells to move in a more inflammatory direction, further skewing immune response.
sIgA helps the rest of the immune system know what it is up against, and how aggressive it needs to be. Low levels of sIgA shift systemic immune response to become more inflammatory. sIgA is not merely 80% of our immune system, but the first signal that lets the rest of the immune system know how to behave. Understanding levels of sIgA can help us decrease reactions to environmental and food allergies and sensitivities, help protect us from infection, and prevent autoimmunity.
The interplay between sIgA and oxidative stress is complex and important, and it’s why we’ve included sIgA in our newest test, the Gut-Ox Stress Test, which is a comprehensive look at the interplay between the gut and oxidative stress.
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