Wheat: The master criminal
For the rest of this post we’ll talk about how wheat is essentially a “master criminal” able to flip our antigen identification system on its head. But unlike a virus, wheat doesn’t break the system to try to evade detection. Instead it intentionally sets off the alarms and provokes the immune system to draw its guns. Tragically it’s also very good at getting immune cells to fire on the wrong target.20
The lock-picker
Part 2 of this series explained how wheat effectively opens the tight junctions of our gut allowing bacteria, large molecules and gliadin from wheat itself to enter the body.21-24
But that’s not the only way wheat breaks in.
A protein in wheat called Wheat Germ Agglutinin (WGA) is very good at binding to the cells in our digestive tract and passing right through them into our blood stream.13, 25, 26 WGA can also bind other particles. So not only can it gain entry into circulation, but it can carry antigens from the gut with it.27, 28
The police-provoker
Above, we discussed how the immune system doesn’t automatically respond to foreign antigens. It first needs a co-stimulation before drawing its guns. We also covered the two things that cause APCs to provide this second signal.
The first was exposure to a large quantity of antigens. By “picking the locks” to the house, wheat essentially flings open the doors allowing a huge flow of antigens from the gut into the body.
The second thing that gets APCs to provide the co-stimulation is inflammation. In Part 3 of this series, I explained how wheat tricks the body into believing it is under perpetual bacterial stress.29-33 This creates a constant inflammatory state that causes the once suppressive DCs to flip and start activating the immune system.34, 35 Other APCs follow suite.30, 32, 36-39
In other words, the once tolerant “pencil-pusher” cops of the immune system become gun happy in a way that would make Arnold Schwarzenegger cringe.13
In short, wheat ensures there’s a co-stimulation. Wheat also breaks tolerance:
WGA is able to enter the body bypassing all the mechanisms of oral tolerance.25, 28 So, the first time WGA and the food antigens bound to it are exposed to the immune system is in circulation where the response is almost always inflammatory.
Worse, in multiple studies of wheat’s effect on mice and humans, wheat reduced the levels of Treg (the immune-suppressors) in favor of a type of T Cell called Th17.29, 34, 40 We’ll explore this shift in greater detail in Part 5. All you need to know for now is Th17 is the loose cannon cop who shoots first, asks questions later.41-43
The red herring
This is the definition of an autoimmune disease. It is a condition where the immune system identifies self-antigens as foreign and attacks its own body.44 In other words, the police accidently shoot the residents.
One popular theory of how autoimmune disease comes about is the viral mimicry theory. A virus enters the body that mimics self-antigens.14 In the process of fighting the virus, the immune system ends up identifying the mimicked self-antigens as foreign.6, 7, 45
For this to happen, the body has to be in an inflamed state. That way APCs provide the co-stimulation required and they also suppress Treg cells which would otherwise prevent a reaction to self. This is why the theorists looked at viruses. Not only would they mimic self-antigens, they’d also create the necessary inflammation.7, 45
However, we’ve just seen that wheat does an equally good job of providing the co-stimulation and shutting down Treg’s. And wheat may provide the mimicry as well, so forget the virus.20, 44, 46-48
Of the over 100 autoimmune conditions identified, the trigger has been discovered for only a handful. One of those is celiac disease. In this condition, gliadin from wheat binds a protein in the body called tissue transglutaminase (tTG). The immune system reacts to tTG-gliadin antigens causing it to attack the digestive tract.39, 49, 50
Gliadin may also cross-react with neural components of the brain and contribute to conditions like multiple sclerosis, gluten ataxia, and autism.46, 47, 51 Similarly, WGA is able to bind to many different cells once inside the body.20, 26, 31 While responding to WGA, the immune system will sometimes also react to its binding tissues.20, 52
What all of this amounts to is the ending to that home invasion story none of us want to hear. Wheat and the police end up in a tense standoff and guns are drawn. Tragically your son gets mistaken for one of the invaders and gets killed in the cross-fire.
Fortunately, while wheat can dysregulate the immune system in all of us, not everyone who eats it develops an autoimmune disease. In the final part of this series we’ll talk about how genetic susceptibility is required for disease.
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