Sialoglycan – Siglec axis in the modulation of dendritic cells functions

Interactions between sialylated glycans and Siglec receptors have been recently described as potential new immune checkpoint that can be targeted to improve anticancer immunity. Myeloid cells have been reported to express a wide range of different Siglecs, however their expression and functions on cancer-associated dendritic cells (DCs) were not fully characterized. We found that classical conventional DCs (cDCs) from cancer patient samples have a high expression of several inhibitory Siglecs including Siglec-7, Siglec-9 and Siglec-10. In subcutaneous murine tumor models, we also found an upregulation of the inhibitory Siglec-E receptor on cancer-associated cDCs. DC cell lines and BMDCs with expression of these inhibitory Siglecs showed impaired maturation states on transcriptome and protein level. Furthermore, ablation of these inhibitory Siglecs from DCs enhanced their capability to prime antigen specific T cells and induce proliferation. Our work provides a deeper understanding of the influence of inhibitory Siglecs on DCs, and reveals a potential new target to improve cancer immunotherapy

Improved sensitivity in ellipsometry of thin biochemical films by employing sublayers

Journal ArticleEllipsometry is widely used for investigating the optical properties of thin films on planar substrates, including films of adsorbed proteins or polymers. The average thickness and effective refractive index of the adsorbed layer are calculated by measuring the A and ¥ ellipsometry parameters. Unfortunately the thickness of the adsorbed protein layers is often too thin to significantly affect the A and Y parameters. However, using a substructure consisting of an additional sublayer placed between the substrate and the adsorbed layer, we can improve the sensitivities of both A and 4* to changes in the adsorbed layer, provided that the thickness of the sublayer is optimized. We show that for a Si02 layer on a Si wafer, the optimum Si02 thickness is about 1350 A when the incident angle is 70 degrees and the wavelength is 6328 A. The materials of the sublayer can be metal, semiconductor and/or dielectric