Characterization of innate immune signalings stimulated by ligands for pattern recognition receptors

Structural characterization of two novel heteropolysaccharides from Catharanthus roseus and the evaluation of their immunological activities

Catharanthus roseus, a plant with significant therapeutic value in Chinese folk medicine, contain numerous secondary metabolites. However, the primary metabolites, specifically polysaccharides which might play an important role in immunotherapy, have received limited attention. In the present study, two novel polysaccharides, designated as CRPS-1 and CRPS-2, were isolated from C. roseus. The structures of CRPS-1 and CRPS-2 were characterized using a combination of HPSEC, HPLC, IR, GC-MS, 1D NMR and 2D NMR. Both CRPS-1 and CRPS-2 were identified as homogeneous heteropolysaccharides. Additionally, the weight-average molecular weight of CRPS-2 was lower than that of CRPS-1. The backbone of CRPS-1 was composed of 1,3-α-L-Araf, 1,5-α-L-Araf, 1,3,5-α-L-Araf, 1,3,4-α-L-Rhap, 1,3-α-D-Galp, 1,3,4-α-D-Galp, 1,4-β-D-Manp, and side chains comprised of T-α-L-Araf, T-β-D-Manp, and β-D-Glcp-(1 → 3)-α-D-Galp-(1 → 3) -α-L-Rhap-(1→. CRPS-2 mainly consisted of 1,3-α-D-Galp, 1,3,4-α-D-Galp, 1,6-β-D-Manp, 1,5-α-L-Araf, 1,3,5-α-L-Araf, 1,3-α-L-Rhap and 1,3,4-α-L-Fucp with complex branching structures. Furthermore, CRPS-2 could significantly enhance proliferation and phagocytosis, as well as the secretion of cytokines in RAW264.7 cells. It demonstrated potent immunoregulatory activity by activating the MAPK/Akt/NF-κB signaling pathways. In summary, the utilization of galactose-enriched and low-molecular-weight polysaccharides exhibits great potential in the advancement of innovative functional foods that may provide health benefits.

RNA sequencing-based longitudinal transcriptomic profiling gives novel insights into the disease mechanism of generalized pustular psoriasis

Background

Generalized pustular psoriasis (GPP) is a rare, episodic, potentially life-threatening inflammatory disease. However, the pathogenesis of GPP, and universally accepted therapies for treating it, remain undefined.

Methods

To better understand the disease mechanism of GPP, we performed a transcriptome analysis to profile the gene expression of peripheral blood mononuclear cells (PBMCs) from patients enrolled at the time of diagnosis and receiving follow-up treatment for up to 6 months.

Results

RNA sequencing data revealed that gene expression in five GPP patients’ PBMCs was profoundly altered following acitretin treatment. Differentially expressed gene (DEG) analysis suggested that genes related to psoriatic inflammation, including CXCL1, CXCL8 (IL-8), S100A8, S100A9, S100A12 and LCN2, were significantly downregulated in patients in remission from GPP. Functional enrichment and annotation analysis unveiled a cluster of DEGs significantly associated with the function of leukocytes, particularly neutrophils. Pathway analysis suggested that a variety of pro-inflammatory pathways were inhibited in patients in remission. This analysis not only reaffirmed known signaling pathways in GPP pathogenesis, but also implicated novel factors and pathways, such as cell cycle regulation pathways. Furthermore, regulator network analysis provided bioinformatics-based support for upstream molecules as potential therapeutic targets such as oncostatin M.

Conclusions

This longitudinal analysis of blood transcriptomes provides the first evidence that dysregulated gene expression in peripheral blood may significantly contribute to psoriatic inflammation in GPP patients. Novel canonical pathways and biomarkers identified in the current research may provide insights to help understand GPP pathobiology and advance novel therapeutics.

Electronic supplementary material

The online version of this article (10.1186/s12920-018-0369-3) contains supplementary material, which is available to authorized users.