ABSTRACT
There can be little doubt that there are intimate and interesting connections between the functioning of the nervous and immune systems. Our interest in this area grew from our studies on the effects of glucocorticoids administered as drugs to mice. This was a worthwhile area to investigate, because glucocorticoids are the most effective drugs for modifying immunologic disease, including allergy, autoimmunity, and transplant rejection. One of the most curious of our findings was that the familiar lymphopenia that follows an injection of glucocorticoid is not due, as had been thought, to lymphocyte destruction. In fact, the missing lymphocytes had left the blood and were sequestered in tissues, especially in the bone marrow (1,2). These lymphocytes remain there for a few days, presumably until glucocorticoids levels fall to normal. They then reenter the circulation, as has been shown in humans and mice (3).
