The effects of illness and nutritional status on various areas of the immune system are important considerations. This is especially true in attempting to define the effects of aging on immune function. Vitamin E apparently has little effect on immune function in vivo or in vitro. Burn trauma results in an overall depletion of circulating T cells, especially CD8+ cells. The receptor for IL-2, an activation marker, is induced not only by antigen and mitogen activation but by endotoxin. This can be seen frequently in older individuals. The T cell antigen receptor is under the control of at least 4 genes, which all are equally transcribed by an activation signal. Studies on genes involved in neurologic disorders have demonstrated that abnormal superoxide dismutase and tubulin gene transcription are not a features of Alzheimer's disease. Also, there are no common viral infections associated with this disorder.
