Binding of [125I]corticotropin releasing factor to blood immunocytes and its reduction in Alzheimer's disease.

The binding of [125I]iodine-labelled corticotropin releasing factor (CRF) was studied using peripheral blood lymphocytes from normal donors and Alzheimer's disease (AD) patients. The high affinity binding of [125I]CRF was found in the membranes of various immunocytes. Monocytes and T cells displayed binding which was several times greater than the binding of brain (cortical) cells. The immunocyte CRF binding was significantly (P less than 0.001) lower in 14 out of 18 (78%) AD patients relative to non-AD controls, suggesting the association of CRF in the pathology of AD. Our data demonstrate that blood immunocytes can be used to analyze deficiency of neurohormone sites in neuropsychiatric diseases, e.g., AD.