Characterization of an immunosuppressive anti-CD40 ligand monoclonal antibody

Impact of the CD40-CD40L dyad in Alzheimer's disease

As the number of elderly individuals rises, Alzheimer's disease (AD), marked by amyloid-beta deposition, neurofibrillary tangle formation, and low-level neuroinflammation, is expected to lead to an ever-worsening socioeconomic burden. AD pathoetiologic mechanisms are believed to involve chronic microglial activation. This phenomenon is associated with increased expression of membrane-bound CD40 with its cognate ligand, CD40 ligand (CD40L), as well as increased circulating levels of soluble forms of CD40 (sCD40) and CD40L (sCD40L). Here, we review the role of this inflammatory dyad in the pathogenesis of AD. In addition, we examine potential therapeutic strategies such as statins, flavonoids, and human umbilical cord blood transplantation, all of which have been shown to modulate CD40-CD40L interaction in mouse models of AD. Importantly, therapeutic approaches focusing on CD40-CD40L dyad regulation, either alone or in combination with amyloid-beta immunotherapy, may provide for a safe and effective AD prophylaxis or treatment in the near future.

SOLUBLE CD40 LIGAND IN DEMENTIA

Some 15-20% of the population over the age of 65 years suffer from dementia, currently one of the leading causes of death behind cardiovascular diseases, cancer and cerebrovascular diseases. The major forms of dementia share in common overactivation of the CD40-CD40-L complex, leading to high levels of proinflammatory cytokine production by immune cells of the central nervous system (CNS), including microglia and astrocytes. Consequently, both neuronal survival and signaling are negatively affected, leading to the characteristic progressive loss of higher cortical functions. We have reviewed the literature concerning the involvement of this complex in the pathology of three major forms of dementia: Alzheimer's-type, HIV-associated and vascular dementia. This is followed by a discussion of current preclinical and clinical therapies that may influence this interaction, and thus point the way toward a future neuroimmunological approach to inhibiting the effects of CD40-CD40-L in neuropsychiatric disease.