Biological Evaluation of Multivalent Lewis X–MGL‐1 Interactions

Abstract

Myeloid C-type lectin receptors (CLRs) expressed by antigen-presenting cells are pattern-recognition receptors involved in the recognition of pathogens as well as of self-antigens. The interaction of carbohydrate ligands with a CLR can trigger immune responses. Although several CLR ligands are known, there is limited insight into CLR targeting by carbohydrate ligands. The weak affinity of lectin-carbohydrate interactions often renders multivalent carbohydrate presentation necessary. Here, we have analyzed the impact of multivalent presentation of the trisaccharide Lewis X (Le(X) ) epitope on its interaction with the CLR macrophage galactose-type lectin-1 (MGL-1). Glycan arrays, including N-glycan structures with terminal Le(X) , were prepared by enzymatic extension of immobilized synthetic core structures with two recombinant glycosyltransferases. Incubation of arrays with an MGL-1-hFc fusion protein showed up to tenfold increased binding to multiantennary N-glycans displaying Le(X) structures, compared to monovalent Le(X) trisaccharide. Multivalent presentation of Le(X) on the model antigen ovalbumin (OVA) led to increased cytokine production in a dendritic cell /T cell coculture system. Furthermore, immunization of mice with Le(X) -OVA conjugates modulated cytokine production and the humoral response, compared to OVA alone. This study provides insights into how multivalent carbohydrate-lectin interactions can be exploited to modulate immune responses.

Fluorescent Neoglycoprotein Gold Nanoclusters: Synthesis and Applications in Plant Lectin Sensing and Cell Imaging

“…Biantennary N-glycan G0 equipped with a C5 amino linker was synthesized as previously described [ 34 ] and the conjugation with OVA was achieved employing disuccinimidyl suberate ester (DSS) as crosslinking reagent (Fig. 2 a) [ 21 , 35 ]. In brief, the conjugation is performed in a two-step reaction: N-glycan G0 is functionalized with a 13-fold excess of DSS linker and then coupled to free amino groups on OVA.…”

Role of the C-Type Lectin Receptors MCL and DCIR in Experimental Colitis

“…The extracellular parts of MCL, DCIR, and MGL1 were expressed as hFc fusion proteins as described previously [38]–[40]. Faecal samples were isolated from colon of female C57BL/6 J mice, filtered through a 40 µm cell strainer (BD Biosciences, Heidelberg, Germany), adjusted to an OD 600 of 0.6 with sterile PBS and inactivated at 65°C for 2 h. Commensal microbes present in the samples were labeled with SYTO 61 fluorescent dye (Life Technologies, Darmstadt, Germany) at 2.5 µM in PBS for 30 min.…”

Myeloid C-Type Lectin Receptors in Viral Recognition and Antiviral Immunity

“…Since an efficient inhibition of virus/CLR interactions by glycan-based carrier systems requires a high binding avidity, multivalent ligand display using different scaffolds has been employed, including nanoparticles, dendrimers, polymers, fullerenes, and glycan-modified antigens [135,136,137,138,139,140]. Besides the inhibition of viral entry into host cells, multivalent CLR targeting also represents a promising strategy to stimulate APC effector functions to boost immune responses [141,142,143]. …”