Zero TE MRI for Craniofacial Bone Imaging

Zero TE MR imaging is a novel technique that achieves a near-zero time interval between radiofrequency excitation and data acquisition, enabling visualization of short-T2 materials such as cortical bone. Zero TE offers a promising radiation-free alternative to CT with rapid, high-resolution, silent, and artifact-resistant imaging, as well as the potential for "pseudoCT" reconstructions. In this report, we will discuss our preliminary experience with zero TE, including technical principles and a clinical case series demonstrating emerging applications in neuroradiology.

In vivo mechanisms by which Irf5 regulates BCR-, TCR- and TLR-induced plasma cell generation and antibody secretion

Generation of antibody secreting cells (ASCs) requires multiple B cell activation pathways, including B cell receptor (BCR), T cell receptor (TCR), and Toll-like receptors (TLRs). In human naïve B cells, we reported that knockdown of interferon regulatory factor 5 (IRF5) resulted in IgD retention, reduced proliferation and plasma cell differentiation, and reduced IgG secretion. Defects were due to early impairments in B cell activation and clonal expansion. Conversely, murine Irf5 was reported to regulate antibody production through direct control of class switch recombination (CSR) at the γ2a locus. To further elucidate distinct and overlapping roles between human and murine IRF5 in the regulation of plasma cell differentiation and antibody production, we performed in vivo analysis of B and T cell differentiation and function in wild-type (wt) and Irf5 knockout (ko) littermate mice after immunization. B and T cell subsets were analyzed by multi-color flow cytometry. Naïve B cells were in vitro differentiated to ASCs with CpG-B, anti-IgM, anti-CD40 and IL-21. Kinetics of B cell activation, AID expression and IgG production were determined. BCR and TCR signaling were examined by phospho-flow. A combination of T-dependent/independent and TLR-dependent/independent immunizations were used to study ASC differentiation. RAG−/− mice were used to determine cell type-specific effects. Results indicate distinct roles for human and murine IRF5 at the early stages of BCR signaling and redundant roles at the later stages of CSR, plasma cell differentiation and antibody secretion via regulation of AID.

Mutation Analysis of Pre-mRNA Splicing Genes PRPF31, PRPF8, and SNRNP200 in Chinese Families with Autosomal Dominant Retinitis Pigmentosa

BACKGROUND

To screen variants in pre-mRNA Splicing genes in 95 Chinese autosomal dominant retinitis pigmentosa (adRP) families.

METHODS

Clinical examination and pedigree analysis were performed. Targeted exome sequencing (TES) and / or Sanger sequencing were performed to detect the variants in genes of Splicing factors and conduct intra-familiar segregation analysis with DNA available. In silico analysis was performed to predict pathogenicity of variants in protein level and in vitro splicing assays were performed to compare splicing variants with their corresponding wildtype about their splicing effect.

RESULTS

In this study, total nine different variants were identified in PRPF31, SNRNP200, and PRPF8 respectively, including six PRPF31 variants [five novel variants 322+1G>A, c.527+2T>G, c.590T>C(p.Leu197Pro), c.1035_1036insGC (p.Pro346Argfs X18), and c.1224dupG (p.Gln409AlafsX66) plus one reported variant c.1060C>T (p.Arg354X)], a recurrent PRPF8 variant c.6930G>T (p.Arg2310Ser), two SNRNP200 variants [one heterozygous and homozygous SNRNP200 recurrent variant c.3260G>A (p.Ser1087Leu), and a reported heterozygous c.2042G>A(p.Arg681His)]. In family 20009, incomplete penetrance was observed. A novel PRPF31 missense variant c.590T>C (p.Leu197Pro) was predicted to be pathogenic in protein level via in silico analysis and in vitro splicing assay demonstrated that two novel splicing PRPF31 variants c.322+1G>A and c.527+2T>G affect splicing compared with the wildtype.

CONCLUSIONS

In our studies, RP-causing variants of pre-mRNA Splicing genes (PRPF31, PRPF8 and SNRNP200) were identified in nine of the ninety-five adRP families respectively, which extend the spectra of RP variant and phenotype. And we provide the first example that SNRNP200-related RP can be caused by both heterozygous and homozygous variants of this gene.

Antiviral effects of simeprevir on multiple viruses

Simeprevir was developed as a small molecular drug targeting the NS3/4A protease of hepatitis C virus (HCV). Unexpectedly, our current work discovered that Simeprevir effectively promoted the transcription of IFN-β and ISG15, inhibited the infection of host cells by multiple viruses including Zika virus (ZIKV), Enterovirus A71 (EV-A71), as well as herpes simplex virus type 1 (HSV-1). However, the inhibitory effects of Simeprevir on ZIKV, EV-A71 and HSV-1 were independent from IFN-β and ISG15. This study thus demonstrates that the application of Simeprevir can be extended to other viruses besides HCV.

FPR2 enhances colorectal cancer progression by promoting EMT process

Formyl peptide receptor-2 (FPR2) has been shown to promote various tumors, but its role in colorectal cancer (CRC) has not been clearly illuminated. The aim of this study was to investigate the effect of FPR2 interference on cell proliferation, migration, invasion, apoptosis, pro-angiogenesis of CRC cells, and also the mechanisms involved. Quantitative PCR assays were applied to assess the expression levels of FPR2 in CRC tissues. CRC cell line SW1116 was chosen to perform this study. We knocked down FPR2 gene by sh-RNA. Then, the cell proliferation was assayed by soft agar colony formation assay, the cell migration capacity was checked by wound healing assay, and cell invasion ability was detected by transwell assay. In addition, flow cytometric analysis was used to detect apoptosis, while endothelial tube formation assay was used to evaluate the effects of FPR2 on pro-angiogenesis in vitro. Tumorigenesis experiment in vivo was performed in nude mice. EMT-related proteins were studied by western blotting. Quantitative PCR demonstrated that FPR2 mRNA was highly expressed in the colorectal cancer tissues. SW1116 cells' capacities of proliferation, migration, invasion, anti-apoptosis and pro-angiogenesis were distinctly suppressed after silencing FPR2 in SW1116 by sh-RNA. Suppression FPR2 mRNA in SW1116 cells suppressed tumorigenicity in nude mice. The expression of proteins related to epithelial-mesenchymal transition (EMT) such as E-cadherin, N-cadherin, Snail, Slug and vimentin was changed after suppressing FPR2. In conclusion, our study demonstrated that FPR2 could promote CRC cells progression in vitro and in vivo that may relate to promoting EMT.

Development of β-elemene and Cisplatin Co-Loaded Liposomes for Effective Lung Cancer Therapy and Evaluation in Patient-Derived Tumor Xenografts

PURPOSE

β-elemene and cisplatin combined chemotherapy currently is one of the most important settings available for lung cancer therapy in China. However, the clinical outcome is limited by their pharmacokinetic drawbacks. On the other hand, most of nanomedicines have failed in clinical development due to the huge differences between heterogeneous clinical tumor tissues and homogenous cell-derived xenografts. In this work, we fabricated a β-elemene and cisplatin co-loaded liposomal system to effectively treat lung cancer.

METHOD

In vitro cytotoxicity of co-loaded liposomes was studied by MTT, trypan and Hoechst/PI staining, and western blot in A549, A549/DDP, and LCC cells. In vivo antitumor efficacy was evaluated in cell-derived and clinically relevant patient-derived xenografts.

RESULTS

Co-loaded liposomes were more cytotoxic to cancer cells, especially than the combination of single-loaded liposomes, benefiting from their simultaneous drug internalization and release. As a result, they exhibited desirable therapeutic outcome in both cell-derived and patient-derived xenografts.

CONCLUSION

β-elemene and cisplatin co-loaded liposomes are a clinically promising candidate for effective lung cancer therapy.

Hyperactivation of the NLRP3 inflammasome protects mice against influenza A virus infection via IL-1β mediated neutrophil recruitment

Host innate immune system is critical for combating invading microbes including Influenza A virus (IAV). As an important arm of the innate immunity, the NLRP3 inflammasome has been found essential for protecting host against IAV challenge, while the mechanism remained elusive. Here we found that mice carrying a gain-of-function mutation in the Nlrp3 gene (Nlrp3^R258W) are strongly resistant to IAV infection. Upon H1N1 IAV infection, the Nlrp3^R258W mice exhibited decreased weight loss, increased survival rate and attenuated lung damage compared with WT littermate controls. Mechanistically, the resistance of Nlrp3^R258W mice to IAV infection was dependent on IL-1β-mediated neutrophil recruitment. Upon IAV infection, mice carrying the Nlrp3^R258W mutation produced more IL-1β than WT mice in the lung, which enhanced neutrophil recruitment locally. The recruited neutrophils facilitated IAV clearance, so that the viral load in Nlrp3^R258W mice was lower than that in control mice. Conversely, neutrophil depletion in Nlrp3^R258W mice compromised IAV clearance. Taken together, our results demonstrate a previously undescribed mechanism by which hyperactivation of the NLRP3 Inflammasome protects mice from IAV infection through IL-1β mediated neutrophil recruitment, thus suggest that positively fine tuning the physiological function of NLRP3 inflammasome can be beneficial for a mammalian host against IAV challenge.

miR-155 Aggravates Liver Ischemia/reperfusion Injury by Suppressing SOCS1 in Mice

Liver ischemia/reperfusion injury (IRI) occurs during partial liver resection and liver transplantation. Activation of Toll-like receptors (TLRs) is a key event triggered by a range of proinflammatory cytokines during liver I/R. Although it has been reported that miR-155 takes part in both innate and adaptive immune responses, the potential role of miR-155 in liver IRI remains unknown. In this study, we found that expression of miR-155 was upregulated during liver I/R by many inflammatory cytokines, and forced expression of miR-155 aggravated hepatocyte injury following liver I/R both in vivo and in vitro. Mice transfected with Ago-miR-155-a chemically modified miR-155-showed enhanced liver severity compared to those transfected with negative control miRNA by inhibiting the expression of SOCS1, the target of miR-155. Thus by the inhibition of SOCS1, the overexpression of miR-155 promoted activation of NF-κB, and elevating the production of proinflammatory cytokines, such TNF-α and IL-6. In conclusion, miR-155 aggravates liver I/R injury in vivo and hepatocyte hypoxia/reoxygenation injury by suppressing the expression of SOCS1.

Antiviral effects of ferric ammonium citrate

Iron is an essential nutrient for cell survival and is crucial for DNA replication, mitochondrial function and erythropoiesis. However, the immunological role of iron in viral infections has not been well defined. Here we found the iron salt ferric ammonium citrate (FAC) inhibited Influenza A virus, HIV virus, Zika virus, and Enterovirus 71 (EV71) infections. Of note, both iron ion and citrate ion were required for the antiviral capability of FAC, as other iron salts and citrates did not exhibit viral inhibition. Mechanistically, FAC inhibited viral infection through inducing viral fusion and blocking endosomal viral release. These were further evidenced by the fact that FAC induced liposome aggregation and intracellular vesicle fusion, which was associated with a unique iron-dependent cell death. Our results demonstrate a novel antiviral function of FAC and suggest a therapeutic potential for iron in the control of viral infections.

Remodelling of the gut microbiota by hyperactive NLRP3 induces regulatory T cells to maintain homeostasis

Inflammasomes are involved in gut homeostasis and inflammatory pathologies, but the role of NLRP3 inflammasome in these processes is not well understood. Cryopyrin-associated periodic syndrome (CAPS) patients with NLRP3 mutations have autoinflammation in skin, joints, and eyes, but not in the intestine. Here we show that the intestines of CAPS model mice carrying an Nlrp3^R258W mutation maintain homeostasis in the gut. Additionally, such mice are strongly resistant to experimental colitis and colorectal cancer; this is mainly through a remodelled gut microbiota with enhanced anti-inflammatory capacity due to increased induction of regulatory T cells (T_regs). Mechanistically, NLRP3^R258W functions exclusively in the lamina propria mononuclear phagocytes to directly enhance IL-1β but not IL-18 secretion. Increased IL-1β boosts local antimicrobial peptides to facilitate microbiota remodelling. Our data show that NLRP3^R258W-induced remodelling of the gut microbiota, induces local T_regs to maintain homeostasis and compensate for otherwise-detrimental intestinal inflammation.

Inflammasomes are involved in gut homeostasis and inflammatory pathologies. The authors show that a hyperactive NLRP3 inflammasome maintains gut homeostasis through remodelling of the gut microbiota and induction of regulatory T cells.

Laparoscopic abdominoperineal excision with trans-abdominal individualized levator transection: interim analysis of a randomized controlled trial

AIM

Extralevator abdominoperineal excision (ELAPR) is challenging 'conventional' abdominoperineal excision (APR), yet the safety and efficacy of ELAPR is still under debate. We therefore developed a laparoscopic APR with trans-abdominal individualized levator transection (LAPR-TILT) approach and compared the outcome with a conventional laparoscopic APR (CLAPR).

METHOD

All eligible patients were entered a single-centre randomized controlled trial to compare CLAPR and LAPR-TILT. We assessed the first 185 patients, including operative findings, complications, histopathology and urogenital function.

RESULTS

Ninety-three patients in the CLAPR group and 92 patients in the APR-TILT group were included for analysis. The APR-TILT procedure took less time [137 (101-175) min vs 146 (102-187) min; P = 0.03], mainly owing to faster perineal dissection. APR-TILT resulted in a reduced rate of bowel perforation (1.1% vs 8.6%; P = 0.04), circumferential resection margin positivity (1.1% vs 10.8%; P = 0.01) and postoperative wound complications (5.4% vs 16.2%; P = 0.02) compared with the CLAPR procedure. At a median follow-up of 19 months after surgery, three patients (3.2%) in the CLAPR group had tumour recurrence while no tumour recurrence occurred in the LAPR-TILT group. Patients who underwent LAPR-TILT reported fewer urinary or sexual problems (LAPR-TILT vs CLAPR, 10.9% vs 24.7% and 17.4% vs 38.7%, respectively).

CONCLUSION

Compared with CLAPR, LAPR-TILT achieved better pathological results for factors that are surrogate parameters for local recurrence. LAPR-TILT could also reduce the risk of urogenital dysfunction.

Characterization of an entomopathogenic fungi target integument protein, Bombyx mori single domain von Willebrand factor type C, in the silkworm, Bombyx mori

The insect cuticle works as the first line of defence to protect insects from pathogenic infections and water evaporation. However, the old cuticle must be shed in order to enter the next developmental stage. During each ecdysis, moulting fluids are produced and secreted into the area among the old and new cuticles. In a previous study, the protein Bombyx mori single domain von Willebrand factor type C (BmSVWC; BGIBMGA011399) was identified in the moulting fluids of Bo. mori and demonstrated to regulate ecdysis. In this study we show that in Bo. mori larvae, BmSVWC primarily locates to the integument (epidermal cells and cuticle), wing discs and head. During the moulting stage, BmSVWC is released into the moulting fluids, and is then produced again by epidermal cells after ecdysis. Fungal infection was shown to decrease the amount of BmSVWC in the cuticle, which indicates that BmSVWC is a target protein of entomopathogenic fungi. Thus, BmSVWC is mainly involved in maintaining the integrity of the integument structure, which serves to protect insects from physical damage and pathogenic infection.

Hyperactivation of the NLRP3 Inflammasome in Myeloid Cells Leads to Severe Organ Damage in Experimental Lupus

Systemic lupus erythematosus (SLE) is an autoimmune syndrome associated with severe organ damage resulting from the activation of immune cells. Recently, a role for caspase-1 in murine lupus was described, indicating an involvement of inflammasomes in the development of SLE. Among multiple inflammasomes identified, the NLRP3 inflammasome was connected to diverse diseases, including autoimmune encephalomyelitis. However, the function of NLRP3 in SLE development remains elusive. In this study, we explored the role of NLRP3 in the development of SLE using the pristane-induced experimental lupus model. It was discovered that more severe lupus-like syndrome developed in Nlrp3^-R258W mice carrying the gain-of-function mutation. Nlrp3^-R258W mutant mice exhibited significantly higher mortality upon pristane challenge. Moreover, prominent hypercellularity and interstitial nephritis were evident in the glomeruli of Nlrp3^-R258W mice. In addition, hyperactivation of the NLRP3 inflammasome in this mouse line resulted in proteinuria and mesangial destruction. Importantly, all of these phenotypes were largely attributed to the Nlrp3^-R258W mutation expressed in myeloid cells, because Cre recombinase-mediated depletion of this mutant from such cells rescued mice from experimental lupus. Taken together, our study demonstrates a critical role for NLRP3 in the development of SLE and suggests that modulating the inflammasome signal may help to control the inflammatory damage in autoimmune diseases, including lupus.

Inhibition of Transforming Growth Factor-β Activation Diminishes Tumor Progression and Osteolytic Bone Disease in Mouse Models of Multiple Myeloma

Transforming growth factor (TGF)-β supports multiple myeloma progression and associated osteolytic bone disease. Conversion of latent TGF-β to its biologically active form is a major regulatory node controlling its activity. Thrombospondin1 (TSP1) binds and activates TGF-β. TSP1 is increased in myeloma, and TSP1-TGF-β activation inhibits osteoblast differentiation. We hypothesized that TSP1 regulates TGF-β activity in myeloma and that antagonism of the TSP1-TGF-β axis inhibits myeloma progression. Antagonists (LSKL peptide, SRI31277) derived from the LSKL sequence of latent TGF-β that block TSP1-TGF-β activation were used to determine the role of the TSP1-TGF-β pathway in mouse models of myeloma. TSP1 binds to human myeloma cells and activates TGF-β produced by cultured human and mouse myeloma cell lines. Antagonists delivered via osmotic pump in an intratibial severe combined immunodeficiency CAG myeloma model or in a systemic severe combined immunodeficiency CAG-heparanase model of aggressive myeloma reduced TGF-β signaling (phospho-Smad 2) in bone sections, tumor burden, mouse IL-6, and osteoclasts, increased osteoblast number, and inhibited bone destruction as measured by microcomputed tomography. SRI31277 reduced tumor burden in the immune competent 5TGM1 myeloma model. SRI31277 was as effective as dexamethasone or bortezomib, and SRI31277 combined with bortezomib showed greater tumor reduction than either agent alone. These studies validate TSP1-regulated TGF-β activation as a therapeutic strategy for targeted inhibition of TGF-β in myeloma.