In keeping with previous work, they found that high- and low-rank individuals showed different levels of responsiveness to a class of hormones called glucocorticoids, which regulate immune-system activity and response to stress.

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Cells use cytokines to communicate with each other, and to regulate the immune response.

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The disease is associated with abnormal levels of norepinephrine and estradiol, hormones that are known to help regulate the immune system.

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On the side, he took part in an international workshop studying the human leukocyte antigen gene complex, which helps regulate the immune system.

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Sure enough the answer, for a substantial fraction of them, was that they regulate aspects of the immune system.

ECONOMIST: Social status and health