Rat Anti-Mouse CD1d (CD1.1) Monoclonal antibody, clone 20H2 (HB323) Functional Grade

Background: alpha-Synuclein (alpha-syn) is a pre-synaptic protein which progressively accumulates in neuronal and non-neuronal cells in neurodegenerative diseases such as Parkinson's disease (PD), dementia with Lewy bodies (DLB), and multiple system atrophy. Recent evidence suggests that aberrant immune activation may be involved in neurodegeneration in PD/DLB. While previous studies have often focused on the microglial responses, less is known about the role of the peripheral immune system in these disorders. Methods: To understand the involvement of the peripheral immune system in PD/DLB, we evaluated T cell populations in the brains of alpha-syn transgenic (tg) mice (e.g., Thy1 promoter line 61) and DLB patients. Results: Immunohistochemical analysis showed perivascular and parenchymal infiltration by CD3+/CD4+ helper T cells, but not cytotoxic T cells (CD3+/CD8+) or B cells (CD20+), in the neocortex, hippocampus, and striatum of alpha-syn tg mice. CD3+ cells were found in close proximity to the processes of activated astroglia, particularly in areas of the brain with significant astrogliosis, microgliosis, and expression of pro-inflammatory cytokines. In addition, a subset of CD3+ cells co-expressed interferon gamma. Flow cytometric analysis of immune cells in the brains of alpha-syn tg mice revealed that CD1d-tet+ T cells were also increased in the brains of alpha-syn tg mice suggestive of natural killer T cells. In post-mortem DLB brains, we similarly detected increased numbers of infiltrating CD3+/CD4+ T cells in close proximity with blood vessels. Conclusion: These results suggest that infiltrating adaptive immune cells play an important role in neuroinflammation and neurodegeneration in synucleinopathies and that modulating peripheral T cells may be a viable therapeutic strategy for PD/DLB.

A synthesis strategy for the swift generation of 4"-modified alpha-galactosylceramide (alpha-GalCer) analogues is described, establishing a chemical platform to comprehensively investigate the structure activity relationships (SAR) of this understudied glycolipid part. The strategy relies on a late-stage reductive ring-opening of a p-methoxybenzylidene (PMP) acetal to regioselectively liberate the 4"-OH position. The expediency of this methodology is demonstrated by the synthesis of a small yet diverse set of analogues, which were tested for their ability to stimulate invariant natural killer T cells (iNKT) in vitro and in vivo. The introduction of a p-chlorobenzyl ether yielded an analogue with promising immunostimulating properties, paving the way for further SAR studies.