CTLA4 and Alzheimer disease: CD152 and GITR particles, which are responsible for the activation of suppressive function, were not altered in AD patients whereas CD62L and CD134 receptors, which are able to modulate the function of other lymphocytes, were markedly increased, reaching 67.9 ± 11.0 and 5.5 ± 1.6 %, respectively, as compared to controls (49.4 ± 13.9 %, p < 0.02 and 3.8 ± 1.7 %, p < 0.05).