“People get exposed to the same virus, the same dose, even the same source. One gets very sick, and the other doesn’t,” [says immunologist John Mellors.] It’s only natural to wonder: Why do some people always seem to fall on the right side of this equation? And could our own immune systems approach the same level with the right tuneup?
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[New research] is starting to illustrate just how your genes, habits and past disease exposures affect the character and strength of your immune response.…
[W]hen a bacterium gets into one of your cells, your HLA genes churn out proteins that flag the cell as infected so that specialized immune cells will swarm in to destroy it. Other HLA genes activate cells that rein in the immune response, so it doesn’t destroy more than necessary.Like fingerprints, everyone’s HLA gene assortment is unique. Your HLA genes give you a broad repertoire of immune defense tactics, but “that repertoire may be great for some microorganisms and lousy for others,” Mellors says.
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Regardless of your T cell balance or your immune track record, there’s a hefty dose of serendipity involved each time your immune system faces a threat. You might consider yourself forever prone to the flu or sniffles, but an X-factor — a cross-country move, a dietary tweak, a new therapy — can unexpectedly realign things and boost your immune potential.