Lipophilic glucose monoesters and glycosides are potent human Mincle agonists.

Macrophage inducible C-type lectin (Mincle) is a pattern recognition receptor on myeloid cells that represents a promising target for Th1-stimulating adjuvants. We report on the synthesis of branched and aromatic glucose monoesters and glycosides and their activation of mouse and human Mincle. In studies using mMincle, derivatives containing aromatic groups in the 6--acyl chain were poor Mincle agonists, while analogues with branched lipophilic groups at the glucose 6-position and anomeric hydroxy or methoxy groups exhibited better Mincle-mediated agonist activity than compounds with a docosyl group at the anomeric position.

Agonistic or antagonistic mucosal-associated invariant T (MAIT) cell activity is determined by the 6-alkylamino substituent on uracil MR1 ligands.

Mucosal-associated invariant T (MAIT) are a subset of innate-like T cells that are activated by uracil ligands presented by MR1. For the first time, we demonstrate that changes to the 6-aminoalkyl chain on uracil agonist 5-OP-RU can determine agonistic or antagonistic MAIT cell activity. Insomuch, a simplified agonist with a functional profile similar to 5-OP-RU, and a new structural class of antagonist that exhibits similar activity to known MAIT cell antagonist Ac-6-FP, were identified.

Stereochemistry, lipid length and branching influences Mincle agonist activity of monoacylglycerides.

Herein, we report on the synthesis of a series of enantiomerically pure linear, iso-branched, and α-branched monoacyl glycerides (MAGs) in 63-72% overall yield. The ability of the MAGs to signal through human macrophage inducible C-type lectin (hMincle) using NFAT-GFP reporter cells was explored, as was the ability of the compounds to activate human monocytes. From these studies, MAGs with an acyl chain length ≥C22 were required for Mincle activation and the production of interleukin-8 (IL-8) by human monocytes.

The effect of MR1 ligand glyco-analogues on mucosal-associated invariant T (MAIT) cell activation.

Mucosal-associated invariant T (MAIT) cells are a subset of recently identified innate-like T lymphocytes that appear to play an important role in many pathologies ranging from viral and bacterial infection, to autoimmune disorders and cancer. MAIT cells are activated via the presentation of ligands by MR1 on antigen presenting cells to the MAIT T cell receptor (TCR), however few studies have explored the effects of systematic changes to the ligand structure on MR1 binding and MAIT cell activation. Herein, we report on the first study into the effects of changes to the sugar motif in the known MAIT cell agonists 7-hydroxy-6-methyl-8-d-ribityllumazine (RL-6-Me-7-OH) and 5-(2-oxopropylideneamino)-6-d-ribitylaminouracil (5-OP-RU).

Evaluation of anti α-d-Glc-(1→4)-α-d-Glc (GAGA4) IgM antibodies as a biomarker for multiple sclerosis.

The correct diagnosis of multiple sclerosis (MS) remains challenging due to the complex pathophysiological and clinical characteristics of the disease. Consequently, there has been immense interest in finding a non-invasive diagnostic test for MS. Recent studies found that serum anti-α-d-Glc-(1→4)-α-d-Glc (GAGA4) IgM antibodies were upregulated in MS patients, and this finding led to the development of a commercial diagnostic test (gMS® Dx test), although the test has poor selectivity and has not been independently validated.

Identification and Biological Activity of Synthetic Macrophage Inducible C-Type Lectin Ligands.

The macrophage inducible C-type lectin (Mincle) is a pattern recognition receptor able to recognize both damage-associated and pathogen-associated molecular patterns, and in this respect, there has been much interest in determining the scope of ligands that bind Mincle and how structural modifications to these ligands influence ensuing immune responses. In this review, we will present Mincle ligands of known chemical structure, with a focus on ligands that have been synthetically prepared, such as trehalose glycolipids, glycerol-based ligands, and 6-acylated glucose and mannose derivatives. The ability of the different classes of ligands to influence the innate, and consequently, the adaptive, immune response will be described, and where appropriate, structure-activity relationships within each class of Mincle ligands will be presented.

Identification, library synthesis and anti-vibriosis activity of 2-benzyl-4-chlorophenol from cultures of the marine bacterium Shewanella halifaxensis.

Summer Gut Syndrome (SGS) is caused by various Vibrio bacterial species and can have negative effects on aquaculture farms worldwide. In New Zealand, SGS is caused by Vibrio harveyii infecting King Salmon (Oncorhynchus tshawytscha). To find leads for the prevention of SGS, we screened the inhibitory effects of 16 strains of Shewanella upon V.