STARTRAC analyses of scRNAseq data from tumor models reveal T cell dynamics and therapeutic targets.

Single-cell RNA sequencing is a powerful tool to examine cellular heterogeneity, novel markers and target genes, and therapeutic mechanisms in human cancers and animal models. Here, we analyzed single-cell RNA sequencing data of T cells obtained from multiple mouse tumor models by PCA-based subclustering coupled with TCR tracking using the STARTRAC algorithm. This approach revealed various differentiated T cell subsets and activation states, and a correspondence of T cell subsets between human and mouse tumors.

Trans-ancestry analysis reveals genetic and nongenetic associations with COVID-19 susceptibility and severity.

COVID-19 presents with a wide range of severity, from asymptomatic in some individuals to fatal in others. Based on a study of 1,051,032 23andMe research participants, we report genetic and nongenetic associations with testing positive for SARS-CoV-2, respiratory symptoms and hospitalization. Using trans-ancestry genome-wide association studies, we identified a strong association between blood type and COVID-19 diagnosis, as well as a gene-rich locus on chromosome 3p21.

Discovery of 6-Oxo-4-phenyl-hexanoic acid derivatives as RORγt inverse agonists showing favorable ADME profile.

The retinoic acid receptor-related orphan nuclear receptor gamma t (RORγt), which is a promising therapeutic target for immune diseases, is a major transcription factor of genes related to psoriasis pathogenesis, such as interleukin (IL)-17A, IL-22, and IL-23R. Inspired by the co-crystal structure of RORγt, a 6-oxo-4-phenyl-hexanoic acid derivative 6a was designed, synthesized, and identified as a ligand of RORγt. The structure-activity relationship (SAR) studies in 6a, which focus on the improvement of its membrane permeability profile by introducing chlorine atoms, led to finding 12a, which has a potent RORγt inhibitory activity and a favorable pharmacokinetic profile.

Discovery of [1,2,4]Triazolo[1,5-]pyridine Derivatives as Potent and Orally Bioavailable RORγt Inverse Agonists.

The retinoic acid receptor-related orphan nuclear receptor γt (RORγt), a promising therapeutic target, is a major transcription factor of genes related to psoriasis pathogenesis such as interleukin (IL)-17A, IL-22, and IL-23R. On the basis of the X-ray cocrystal structure of RORγt with , an analogue of the known piperazine RORγt inverse agonist , triazolopyridine derivatives of were designed and synthesized, and analogue was found to be a potent RORγt inverse agonist. Structure-activity relationship studies on , focusing on the treatment of its metabolically unstable cyclopentyl ring and the central piperazine core, led to a novel analogue, namely, 6-methyl--(7-methyl-8-(((2,4)-2-methyl-1-(4,4,4-trifluoro-3-(trifluoromethyl)butanoyl)piperidin-4-yl)oxy)[1,2,4]triazolo[1,5-]pyridin-6-yl)nicotinamide (), which exhibited strong RORγt inhibitory activity and a favorable pharmacokinetic profile.

High-Throughput Implementation of the NanoBRET Target Engagement Intracellular Kinase Assay to Reveal Differential Compound Engagement by SIK2/3 Isoforms.

The real-time quantification of target engagement (TE) by small-molecule ligands in living cells remains technically challenging. Systematic quantification of such interactions in a high-throughput setting holds promise for identification of target-specific, potent small molecules within a pathophysiological and biologically relevant cellular context. The salt-inducible kinases (SIKs) belong to a subfamily of the AMP-activated protein kinase (AMPK) family and are composed of three isoforms in humans (SIK1, SIK2, and SIK3).

Dual Mechanisms for Balancing Th17 and Treg Cell Fate by CREB.

Th17 cells, which express the cytokine IL-17A, and master regulator RORγt, are important in the inflammatory response to fungal and bacterial pathogens, but also have a pathogenic role in many inflammatory disorders. In contrast, regulatory T cells (Treg), expressing the Foxp3 transcription factor, have a suppressive function and can dampen an immune response. The appropriate balance of these distinct effector functions is critical for an effective immune response and autoimmunity can arise if this process goes awry.

Differential Roles for Interleukin-23 and Interleukin-17 in Intestinal Immunoregulation.

Interleukin-23 (IL-23) and IL-17 are cytokines currently being targeted in clinical trials. Although inhibition of both of these cytokines is effective for treating psoriasis, IL-12 and IL-23 p40 inhibition attenuates Crohn's disease, whereas IL-17A or IL-17 receptor A (IL-17RA) inhibition exacerbates Crohn's disease. This dichotomy between IL-23 and IL-17 was effectively modeled in the multidrug resistance-1a-ablated (Abcb1a(-/-)) mouse model of colitis.

TPL2-mediated activation of ERK1 and ERK2 regulates the processing of pre-TNF alpha in LPS-stimulated macrophages.

Activation of the TPL2-MKK1/2-ERK1/2 signalling pathway is essential for lipopolysaccharide (LPS)-stimulated production of TNF alpha in macrophages. Here, we demonstrate that, unexpectedly, TPL2-deficient or MKK1-inhibited macrophages produce near normal levels of pre-TNF alpha when TLR2, TLR4 and TLR6 are activated by their respective agonists, but fail to secrete TNFalpha. We show that LPS stimulates the appearance of pre-TNFalpha at the cell surface and that this is prevented by inhibition of MAPK kinases 1 and 2 (MKK1/2) or in TPL2-deficient macrophages.

ABIN-2 is required for optimal activation of Erk MAP kinase in innate immune responses.

The TPL-2 MEK kinase is essential for activation of the Erk MAP kinase pathway during innate immune responses. TPL-2 is found in complex with ABIN-2 (A20-binding inhibitor of NF-kappaB 2). Here, using antigen-presenting cells from ABIN-2-deficient mice, we show that ABIN-2 was required for optimal activation of Erk induced by receptors that signal via TPL-2, including Toll-like receptor 4 and tumor necrosis factor receptor 1 in macrophages, and CD40 in B cells.

MAP kinase kinase kinases and innate immunity.

Toll-like receptors, which respond to invariant microbial molecules, and receptors for the proinflammatory cytokines tumour necrosis factor and interleukin-1 are crucial for initiation and regulation of innate immune responses. These receptors activate each of the major mitogen-activated protein (MAP) kinase subtypes, extracellular signal-regulated protein kinases, c-Jun amino-terminal kinases and p38 MAP kinases, which are crucial for cell survival and controlling the expression of immune mediators. Here we discuss recent studies characterizing the specific MAP kinase kinase kinases (MAP 3-kinases) that link MAP kinases to receptors involved in innate immunity and the mechanisms by which the activity of MAP 3-kinases is regulated by such receptors.

CD45 ectodomain controls interaction with GEMs and Lck activity for optimal TCR signaling.

The transmembrane phosphatase CD45 regulates both Lck activity and T cell receptor (TCR) signaling. Here we have tested whether the large ectodomain of CD45 has a role in this regulation. A CD45 chimera containing the large ectodomain of CD43 efficiently rescues TCR signaling in CD45-null T cells, whereas CD45 chimeras containing small ectodomains from other phosphatases do not.