P52 is the C-terminal region of P159 which is a adhesin of Mycoplasma hyopneumonlae. The P52 fragment was cloned into expression vector pET-30a and sequenced. The recombinant plasmid was transformed into BL21 and protein expression was detected by SDS-PAGE. The P52 protein was about 50 ku and expressed in high yield (28 % ). Western blot indicated that the P52 protein reacted with specific antibodies. Indirect immunofluorescence assay showed that P52 protein had successfully expressed in eukaryotic systems.
Natural killer T (NKT) cells are a key component of innate immunity. Importantly, a growing body of evidence indicates that NKT cells play an integral role in various acute and chronic liver injuries. NKT cells participate in the progression of an injury through the secretion of cytokines, which promote neutrophil infiltration and enhance Fas ligand (FasL) and granzyme-mediated NKT cytotoxic activity. Therefore, examining the role of NKT cells in hepatic disease is critical for a comprehensive understanding of disease pathogenesis and may provide insight into novel approaches for treatment. For more than a century, mouse models that imitate the physiopathological conditions of human disease have served as a critical tool in biological and medical basic research, including studies of liver disease. Here, we review the role of NKT cells in various mouse models of hepatitis.
Endotoxin tolerance (ET) is a protective mechanism in the process of sepsis, septic shock, and their sequelae including uncontrolled inflammation. Accumulating evidence has shown that peripheral T cells contribute to the induction of ET. However, what and how T-cell development contributes to ET inductions remain unclear.Mice were intraperitoneally injected with LPS at a concentration of 5 mg/kg to establish an LPS tolerance model and were divided into two groups: a group examined 72 h after LPS injection (72-h group) and a group examined 8 days after LPS injection (8-day group). Injection of PBS was used as a control. We performed high-throughput sequencing to analyze the characteristics and changes of CD4+SP TCRβ CDR3 repertoires with respect to V direct to J rearrangement during the ET induction. Moreover, the proportion and proliferation, as well as surface molecules such as CD80 and CD86, of F4/80+ macrophages were analyzed using FCM. Furthermore, ACT assay was designed and administered by the tail vein into murine LPS-induced mouse model to evaluate the role of F4/80+ macrophages on the development of CD4+SP thymocytes in ET condition.We found that the frequency and characteristics of the TCRβ chain CDR3 changed obviously under condition of ET, indicating the occurrence of TCR rearrangement and thymocyte diversification. Moreover, the absolute numbers of F4/80+ macrophages, but not other APCs, were increased in thymic medulla at 72-h group, accompanied by the elevated function-related molecules of F4/80+ macrophages. Furthermore, adoptively transferred OVA332-339 peptide-loaded macrophages into Rag-1-/- mice induced the clone deletion of OVA-specific CD4+SP, thereby ameliorating the pathology in lung tissue in LPS challenge.These data reveal that the frequency and characteristics of the TCRβ chain CDR3 undergo dynamic programming under conditions of LPS tolerance. Furthermore, the peripheral macrophages may be a key factor which carry peripheral antigen to thymic medulla and affect the negative selection of T-cell population, thereby contributing to the formation of ET. These results suggest that the clone selection in thymus in ET may confer protection against microbial sepsis.
Hypoxic-ischemic (HI) induced perinatal white matter injury (PWMI) is a major cause of neurologic disabilities characterized by selective oligodendroglial death and myelin disruption. Galectin-3 (Gal-3) modulates postnatal subventricular zone gliogenesis and attenuates ischemic injury. However, the association between Gal-3 and myelin formation still remains unclear. In this study, we first perform Gal-3 knockdown (KD) to identify the importance of Gal-3 on myelin formation. Our results show impeded myelin formation, manifested by Olig2/CC1 (+) mature oligodendrocytes number, expression of oligodendroglial maturation-associated markers (MBP and CNPase), and myelin thickness and integrity. Then we perform recombinant Gal-3 (rGal-3) administration by intracerebroventricular injection. Notably, although rGal-3 administration shows no beneficial effect on oligodendrogenesis and myelin formation under normal condition, our results show that rGal-3 administration attenuates cognitive deficits and drives remyelination after PWMI, which are coupled to signs of enhanced myelin resiliency and cognition. Also, our results indicates that the significant increases in substrates for remyelination of rGal-3 administration are accompanied by enhanced Iba-1 (microglia marker)/ Mrc1 (M2 marker) (+) microglia and decreased Iba-1/ iNOS (M1 marker) (+) microglia. Altogether, our data in this research confirm the association between Gal-3 and myelin formation, underscore its position for the capacity for remyelination and restoration of function, and unveils the efficacy of rGal-3 administration with anti-inflammatory phenotype microglia (M2 microglia) activation. Thus, the findings suggest that Gal-3 plays a significant role in myelin formation and remyelination restoration.
Objective
To explore the effect of TAK-242, TLR4 inhibitor, on the secreting inflammatory cytokines in BV2 microglia caused by LPS.
Methods
The inflammatory reaction cells were inducedby LPS. (1)Microglias BV2 were cultured with different concentrations of TAK-242, and then , the cell survival rate was detected by cck-8 kit to select the suitable concentration; (2)Microglias BV2 were cultured with different concentrations of lipopolysaccharide(LPS)(0, 0.1, 0.5, 1μg/mL), and then, the TLR4 mRNA expression was detected by Quantitative real-time PCR(qRT-PCR); (3)Microglias BV2 were divided into four groups: Control group, TAK-242 group, LPS group and LPS+ TAK-242 pretreatment group, and then, the TLR4, MYD88, IL-1β, IL-6 mRNA expression were detected by Quantitative real-time PCR(qRT-PCR).
Results
(1)CCK-8: Compared with control group, low concentration of TAK-242 have no effect on the viability of BV2 cells. Compared with LPS group, pretreating of TAK-242(1μM) especially increased the viability of BV2 cells (P<0.05). (2)qRT-PCR: compared with control group, LPS can increase the TLR4 mRNA expression (P<0.05); (3)qRT-PCR: compared with control group, LPS can increase the TLR4mRNA, MyD88mRNA, IL-1βmRNA and IL-6 mRNA expression (P<0.05); Compared with LPS group, pretreating of TAK-242(1μM) can significantly decrease the TLR4mRNA, MyD88mRNA, IL-1βmRNA and IL-6 mRNA expression (P<0.05).
Conclusion
TLR4 signal pathway can be activateed by LPS; TAK-242 can decrease TLR4mRNA, MyD88mRNA, IL-1βmRNA and IL-6 mRNA expression and increase the cells viability.
Key words:
TLR4; TAK-242; LPS; BV2 microglia cells
Toll-like receptor (TLR) 4 signalling is critical for innate immunoinflammatory response and widely triggers the development of various types of clinical diseases. MicroRNA-7 (miR-7) is well documented to play an important regulatory role in various biological events. However, the exact role of miR-7 in TLR4 signalling pathway remains to be fully elucidated. In the present study, we found that miR-7 expression in TLR4 signalling-activated bone marrow-derived macrophages (BMDMs) stimulated by LPS was dramatically increased. Importantly, miR-7 deficiency significantly enhanced the production of related inflammatory cytokines including IL-1β, IL-6 and IL-12, as well as TNF-α, on LPS-activated BMDMs, accompanied by elevated transduction of TLR4 signalling including Myd88-dependent and Myd88-independent pathways, whereas miR-7 overexpression significantly decreased the transduction of TLR4 signalling and the production of related inflammatory cytokines. Mechanistically, we identified family with sequence similarity 177, member A (FAM177A) as a novel target molecule of miR-7. Furthermore, down-regulation of FAM177A using RNAi could impair the transduction of TLR4 signalling. Finally, down-regulation of FAM177A also reversed the effect of miR-7 deficiency on TLR4 signalling transduction and production of related inflammatory cytokines on BMDMs. Therefore, we provide the new evidence that miR-7 acts as a novel negative fine-tuner in regulating TLR4 signalling pathways by targeting FAM177A, which might throw light on the basal understanding on the regulatory mechanism of TLR4 signalling and benefit the development of therapeutic strategies against related clinical diseases.
Abstract Background: C-Jun, a critical component of AP-1, exerts essential functions in various tumors, including melanoma, and is believed to be a druggable target for cancer therapy. Unfortunately, no effective c-Jun inhibitors are currently approved for clinical use. The advent of immune checkpoint inhibitor (ICI) has brought a paradigm shift in melanoma therapy, but more than half of patients fail to exhibit clinical responses. The exploration of new combination therapies has become the current pursuit of melanoma treatment strategy. This study aims to screen out Chinese herbal monomers that can target c-Jun, explore the combined effect of c--Jun inhibitor and ICI, and further clarify the related molecular mechanism. Methods: We adopted a combinatorial screening strategy, including molecular docking, ligand-based online approaches and consensus quantitative structure-activity relationship (QSAR) model, to filter out c-Jun inhibitors from a traditional Chinese medicine (TCM) library. A mouse melanoma model was used to evaluate the therapeutic efficacy of monotherapy and combination therapy. Multicolor flow cytometry was employed to assess the tumor microenvironment (TME). Multiple in vitro assays were performed to verify down-streaming signaling pathway. CD4+ T-cell differentiation assay was applied to investigate Treg differentiation in vitro . Results: Ailanthone (AIL) was screened out as a c-Jun inhibitor, and inhibited melanoma cell growth by directly targeting c-Jun and promoting its degradation. Surprisingly, AIL also facilitated the therapeutic efficacy of anti-programmed death ligand-1 (PD-L1) in melanoma cells by reducing the infiltration of Tregs in TME. Additionally, AIL treatment inhibited c-Jun-induced PD-L1 expression and secretion. As a consequence, Treg differentiation was attenuated after treatment with AIL through the c-Jun/PD-L1 axis. Conclusions: Our findings identified AIL as a novel c-Jun inhibitor, and revealed its previously unrecognized anti-melanoma effects and the vital role in regulating TME by Treg suppression, which provides a novel combination therapeutic strategy of c-Jun inhibition by AIL with ICI.