Glial fibrillary acidic protein stimulates proliferation and immunoglobulin synthesis of lymphocytes from Alzheimer's disease patients.

The level of anti-GFAP (glial fibrillary acidic protein) IgG antibody titer was assayed in sera of patients with Alzheimer's disease, multi-infarct dementia, and the age-matched control subjects. Significantly higher level of anti-CFAP titer was found in sera of Alzheimer's disease patients. The in vitro lymphocyte response was studied by stimulation with GFAP and interleukin 2 (IL-2). The lymphocytes of Alzheimer's disease patients showed higher proliferative response than those of the control by GFAP and IL-2 stimulation. The IgG secretion by lymphocytes from Alzheimer's disease patients was also stimulated by GFAP as well as by GFAP plus IL-2. The results demonstrate that the lymphocytes of Alzheimer's disease patients are more responsive to GFAP than those of the control subjects.