Abstract: The subject invention provides methods of treating amyloidogenic diseases, comprising the administration of therapeutically effective amounts of a composition comprising a carrier and an agent that interferes with the interaction of CD40L and CD40R to an individual afflicted with an amyloidogenic disease. Also provided are methods and/or assay systems for the identification of compounds or other small molecules capable of disrupting the CD40R/CD40L signaling pathway.

Abstract: The present invention provides a method of treating Alzheimer's Disease by blocking CD-40 receptor-mediated, A?-induced microglial cell activation with an agent. Also provided is a method of determining the therapeutic effectiveness of an agent for Alzheimer's Disease by measuring the inhibition of the interaction between the CD40 receptor and its ligand (CD40L) in the presence of the agent. The present invention further provides a method of testing the efficacy of a therapeutic agent by producing a TgAppSW/CD40L deficient mouse and administering to the mouse the therapeutic agent to be tested and determining the efficacy of the drug in suppressing neurodegeneration of Alzheimer's Disease.

Abstract: There is provided an assay method for determining the effect of an agent on Alzheimer's Disease pathology by treating microglial cells with A&bgr; peptides, adding CD40 ligand to the microglial cells, adding a therapeutic agent to the microglial cells, and measuring Alzheimer's Disease pathology. Also provided is a method of determining therapeutic effectiveness of an agent for Alzheimer's Disease by measuring the inhibition of CD40-CD40L binding in the presence of the agent. An assay for determining the effect of an agent on Alzheimer's Disease pathology having A&bgr; peptides for adding to microglial cells, CD40 ligand for being added to the microglial cells, a therapeutic agent being added to the microglial cells and a measuring device for reassuring Alzheimer's Disease pathology is also provided.

Abstract: CD45 isoform switching from the CD45RA to the CD45RO isoform is an indicator of peripheral CD4+ T lymphocyte function, as well as other blood cells. CD45 isoforms are altered on blood cells from AD patients compared to controls, showing significantly lower levels of CD45RA, and an increase in the CD45RO/CD45RA ratio compared to age-matched normal participants. The invention includes a method of assessing the risk of developing, of diagnosing, or of measuring the progression of Alzheimer's disease in a patient comprising of obtaining a blood sample from a patient, determining CD45 isoform expression of blood cells contained in the blood sample, and relating the determined CD45 isoform expression to an assessment of the risk of developing the disease, a diagnosis of the disease, or a measure of the progression of the disease. The blood cells, for purposes of illustration and not limitation, may comprise monocytes, macrophages, lymphocytes, or combinations thereof.

Abstract: A method of inhibiting the negative effects of beta-amyloid in the brain of an animal comprising administering an effective amount of a compound that modulates CD45 activity. This invention also relates to compositions for use in stimulating CD45, and assays for use in finding compounds useful in inhibiting the negative effects of beta-amyloid. An assay for use in identifying compounds that inhibit the negative effects of beta-amyloid comprises (a) contacting immune cells with a predetermined amount of one or more test compounds in the presence of beta-amyloid or one or more peptides derived therefrom, (b) monitoring the amount of one or more inflammatory molecules released by the immune cells, and (c) comparing the amount found in step (b) with another amount found in the absence of the one or more test compounds or using a different predetermined amount the one or more test compounds.