5-HT7R enhances neuroimmune resilience and alleviates meningitis by promoting CCR5 ubiquitination.

INTRODUCTION: Excessive immune activation induces tissue damage during infection. Compared to external strategies to reconstruct immune homeostasis, host balancing ways remain largely unclear. OBJECTIVES: Here we found a neuroimmune way that prevents infection-induced tissue damage. METHODS: By FACS and histopathology analysis of brain Streptococcus pneumonia meningitis infection model and behavioral testing. Western blot, co-immunoprecipitation, and ubiquitination analyze the Fluoxetine initiate 5-HT7R-STUB1-CCR5 K48-linked ubiquitination degradation. RESULTS: Fluoxetine, a selective serotonin reuptake inhibitor, or the agonist of serotonin receptor 5-HT7R, protects mice from meningitis by inhibiting CCR5-mediated excessive immune response and tissue damage. Mechanistically, the Fluoxetine-5-HT7R axis induces proteasome-dependent degradation of CCR5 via mTOR signaling, and then recruits STUB1, an E3 ubiquitin ligase, to initiate K48-linked polyubiquitination of CCR5 at K138 and K322, promotes its proteasomal degradation. STUB1 deficiency blocks 5-HT7R-mediated CCR5 degradation. CONCLUSION: Our results reveal a neuroimmune pathway that balances anti-infection immunity via happiness neurotransmitter receptor and suggest the 5-HT7R-CCR5 axis as a potential target to promote neuroimmune resilience.

TCR ß chain repertoire characteristic between healthy human CD4+ and CD8+ T cells.

T cell is vital in the adaptive immune system, which relays on T-cell receptor (TCR) to recognize and defend against infection and tumors. T cells are mainly divided into well-known CD4+ and CD8+ T cells, which can recognize short peptide antigens presented by major histocompatibility complex (MHC) class II and MHC class I respectively in humoral and cell-mediated immunity. Due to the Human Leukocyte Antigen (HLA) diversity and restriction with peptides complexation, TCRs are quite diverse and complicated. To better elucidate the TCR in humans, the present study shows the difference between the TCR repertoire in CD4+ and CD8+ T cells from 30 healthy donors. The result showed count, clonality, diversity, frequency, and VDJ usage in CD4+ and CD8+ TCR-ß repertoire is different, but CDR3 length is not. The Common Clone Cluster result showed that CD4+ and CD8+ TCR repertoires are connected separately between the bodies, which is odd considering the HLA diversity. More knowledge about TCR makes more opportunities for immunotherapy. The TCR repertoire is still a myth for discovery.

Neuropeptide Calcitonin Gene-Related Peptide Promotes Immune Homeostasis of Bacterial Meningitis by Inducing Major Histocompatibility Complex Class II Ubiquitination.

BACKGROUND: Calcitonin gene-related peptide (CGRP), an immunomodulatory neuropeptide, is important for regulating pain transmission, vasodilation, and the inflammatory response. However, the molecular mechanisms of the CGRP-mediated immune response remain unknown. METHODS: The effects of CGRP on bacterial meningitis (BM) and its underlying mechanisms were investigated in BM mice in vivo and macrophages in vitro. RESULTS: Peripheral injection of CGRP attenuated cytokine storms and protected mice from fatal pneumococcal meningitis, marked by increased bacterial clearance, improved neuroethology, and reduced mortality. When the underlying mechanisms were investigated, we found that CGRP induces proteasome-dependent degradation of major histocompatibility complex class II (MHC-II) in macrophages and then inhibits CD4+ T-cell activation. MARCH1 was identified as an E3 ligase that can be induced by CGRP engagement and promote K48-linked ubiquitination and degradation of MHC-II in macrophages. These results provide new insights into neuropeptide CGRP-mediated immune regulation mechanisms. CONCLUSIONS: We conclude that targeting the nervous system and manipulating neuroimmune communication is a promising strategy for treating intracranial infections like BM.

Chinese Patent Medicine Liuweiwuling Tablet had Potent Inhibitory Effects on Both Wild-Type and Entecavir-Resistant Hepatitis B Virus (HBV) in vitro and Effectively Suppressed HBV Replication in Mouse Model.

Liuweiwuling Tablet (LWWL) is a licensed Chinese patent medicine (approval number: Z20060238) included in the national health insurance for anti-inflammation of chronic HBV infection, whereas its anti-HBV effect remains clarification. The study aimed to clarify its antiviral effect and related mechanisms. HepG2.2.15 cells (wild-type HBV-replicating cells) and HepG2. A64 cells (entecavir-resistant HBV-replicating cells) were used for in vitro test. Hydrodynamic injection-mediated HBV-replicating mouse model was used for in vivo test. Active compounds and related mechanisms for antiviral effect of LWWL were analyzed using network pharmacology and transcriptomics. The inhibition rates of LWWL (0.8 mg/ml) on HBV DNA, HBsAg, and pgRNA were 57.06, 38.55, and 62.49% in HepG2.2.15 cells, and 51.57, 17.57, and 53.88% in HepG2. A64 cells, respectively. LWWL (2 g kg-1 d-1 for 4 weeks)-treated mice had 1.16 log10 IU/mL decrease of serum HBV DNA, and more than 50% decrease of serum HBsAg/HBeAg and hepatic HBsAg/HBcAg. Compared to tenofovir control, LWWL was less effective in suppressing HBV DNA but more effective in suppressing HBV antigens. Thirteen differentially-expressed genes were found in relation to HBV-host interaction and some of them were enriched in interferon (IFN)-ß pathway in LWWL-treated HepG2.2.15 cells. CD3+CD4+ T-cell frequency and serum IFN-γ were significantly increased in LWWL-treated mice compared to LWWL-untreated mice. Among 26 compounds with potential anti-HBV effects that were predicted by network pharmacology, four compounds (quercetin, luteolin, wogonin, and kaempferol) were experimentally confirmed to have antiviral potency. In conclusion, LWWL had potent inhibitory effect on both wild-type and entecavir-resistant HBV, which might be associated with increasing IFN-ß and IFN-γ production.

Spliceosome protein Eftud2 promotes colitis-associated tumorigenesis by modulating inflammatory response of macrophage.

Alternative splicing (AS) of mRNA is known to be involved in regulation of immune cell differentiation and activation. Elongation factor Tu GTP binding domain containing 2 (Eftud2) is an AS factor to potentially modulate innate immune response in macrophages. In this study, we investigate its involvement in the pathogenesis of colitis-associated cancer (CAC). Using an established mouse model of CAC, we show that Eftud2 is constantly overexpressed in the colonic tissues as well as infiltrating macrophages. Myeloid-specific knockout of Eftud2 remarkably suppresses chronic intestinal inflammation and tumorigenesis, which is associated with decreased production of inflammatory cytokines and tumorigenic factors. Repression of colonic inflammation and colorectal tumor development in Eftud2-deficient mice is due to the impaired activation of NF-κB signaling in LPS-challenged macrophages. Furthermore, the alteration of Eftud2-mediated AS involving the components of TLR4-NF-κB cascades underlies the impairment of NF-κB activation. Overall, these findings provide new insights into the tight link between inflammation and cancer and modulation of AS in innate immune signals may be a potentially therapeutic avenue for CAC treatment.

An epithelial-to-mesenchymal transition-inducing potential of granulocyte macrophage colony-stimulating factor in colon cancer.

Growing evidence shows that granulocyte macrophage colony-stimulating factor (GM-CSF) has progression-promoting potentials in certain solid tumors, which is largely attributed to the immunomodulatory function of this cytokine in tumor niches. However, little is known about the effect of GM-CSF on cancer cells. Herein, we show that chronic exposure of colon cancer cells to GM-CSF, which harbor its receptor, leads to occurrence of epithelial to mesenchymal transition (EMT), in time and dose-dependent manners. These GM-CSF-educated cancer cells exhibit enhanced ability of motility in vitro and in vivo. Furthermore, GM-CSF stimulation renders colon cancer cells more resistant to cytotoxic agents. Mechanistic investigation reveals that MAPK/ERK signaling and EMT-inducing transcription factor ZEB1 are critical to mediate these effects of GM-CSF. In specimen of CRC patients, high-level expression of GM-CSF positively correlates with local metastases in lymph nodes. Moreover, the co-expression of GM-CSF and its receptors as well as phosphorylated ERK1/2 are observed. Thus, our study for the first time identifies a progression-promoting function of GM-CSF in colon cancer by inducing EMT.

A fluorogenic probe with aggregation-induced emission characteristics for carboxylesterase assay through formation of supramolecular microfibers.

Herein, we report a novel fluorescent "light-up" probe useful for carboxylesterase assay that is based on a tetraphenylethylene derivative containing carboxylic ester groups. The specific cleavage of the carboxylic ester bonds by carboxylesterase results in the generation of a relatively hydrophobic moiety that self-assembles into supramolecular microfibers, thus giving rise to "turn-on" fluorescent signals. A high sensitivity towards carboxylesterase was achieved with a detection limit as low as 29 pM, which is much lower than the corresponding assays based on other fluorescent approaches.

Incorporation of tyrosine phosphate into tetraphenylethylene affords an amphiphilic molecule for alkaline phosphatase detection, hydrogelation and calcium mineralization.

Simple conjugation of tyrosine-phosphate with tetraphenylethylene generates a new amphiphile, which not only undergoes enzymatic dephosphorylation to generate a relative hydrophobic residue for alkaline phosphatase (ALP) detection with significant enhancement of the fluorescence signals, but also self-assembles in water to result in a novel supramolecular hydrogel with gelation-enhanced fluorescence emission features upon the changes of pH. In addition, the highly ordered micelle nanostructures self-assembled from this amphiphile exhibit the ability to serve as efficient templates to promote the nucleation and growth of calcium phosphate. Since amino acids and peptides are an important class of bioactive entities whose functions range from biomolecular recognition to supramolecular self-assembly, this study demonstrates the potential to generate an amphiphile with a novel molecular architecture from the TPE and amino acid conjugate with multifunctional properties.