IFITM3 inhibits severe fever with thrombocytopenia syndrome virus entry and interacts with viral Gc protein.

Severe fever with thrombocytopenia syndrome (SFTS) is an emerging tick-borne hemorrhagic fever disease with high fatality rate of 10%-20%. Vaccines or specific therapeutic measures remain lacking. Human interferon inducible transmembrane protein 3 (hIFITM3) is a broad-spectrum antiviral factor targeting viral entry. However, the antiviral activity of hIFITM3 against SFTS virus (SFTSV) and the functional mechanism of IFITM3 remains unclear. Here we demonstrate that endogenous IFITM3 provides protection against SFTSV infection and participates in the anti-SFTSV effect of type Ⅰ and Ⅲ interferons (IFNs). IFITM3 overexpression exhibits anti-SFTSV function by blocking Gn/Gc-mediated viral entry and fusion. Further studies showed that IFITM3 binds SFTSV Gc directly and its intramembrane domain (IMD) is responsible for this interaction and restriction of SFTSV entry. Mutation of two neighboring cysteines on IMD weakens IFITM3-Gc interaction and attenuates the antiviral activity of IFITM3, suggesting that IFITM3-Gc interaction may partly mediate the inhibition of SFTSV entry. Overall, our data demonstrate for the first time that hIFITM3 plays a critical role in the IFNs-mediated anti-SFTSV response, and uncover a novel mechanism of IFITM3 restriction of SFTSV infection, highlighting the potential of clinical intervention on SFTS disease.

The "LLQY" Motif on SARS-CoV-2 Spike Protein Affects S Incorporation into Virus Particles.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike (S) glycoprotein mediates viral entry and membrane fusion. Its cleavage at S1/S2 and S2' sites during the biosynthesis in virus producer cells and viral entry are critical for viral infection and transmission. In contrast, the biological significance of the junction region between both cleavage sites for S protein synthesis and function is less understood. By analyzing the conservation and structure of S protein, we found that intrachain contacts formed by the conserved tyrosine (Y) residue 756 (Y756) with three α-helices contribute to the spike's conformational stability. When Y756 is mutated to an amino acid residue that can provide hydrogen bonds, S protein could be expressed as a cleaved form, but not vice versa. Also, the L753 mutation linked to the Y756 hydrogen bond prevents the S protein from being cleaved. Y756 and L753 mutations alter S protein subcellular localization. Importantly, Y756 and L753 mutations are demonstrated to reduce the infectivity of the SARS-CoV-2 pseudoviruses by interfering with the incorporation of S protein into pseudovirus particles and causing the pseudoviruses to lose their sensitivity to neutralizing antibodies. Furthermore, both mutations affect the assembly and production of SARS-CoV-2 virus-like particles in cell culture. Together, our findings reveal for the first time a critical role for the conserved L753-LQ-Y756 motif between S1/S2 and S2' cleavage sites in S protein synthesis and processing as well as virus assembly and infection. IMPORTANCE The continuous emergence of SARS-CoV-2 variants such as the delta or lambda lineage caused the continuation of the COVID-19 epidemic and challenged the effectiveness of the existing vaccines. Logically, the spike (S) protein mutation has attracted much concern. However, the key amino acids in S protein for its structure and function are still not very clear. In this study, we discovered for the first time that the conserved residues Y756 and L753 at the junction between the S1/S2 and S2' sites are very important, like the S2' cleavage site R815, for the synthesis and processing of S protein such as protease cleavage, and that the mutations severely interfered with the incorporation of S protein into pseudotyped virus particles and SARS-CoV-2 virus-like particles. Consequently, we delineate the novel potential target for the design of broad-spectrum antiviral drugs in the future, especially in the emergence of SARS-CoV-2 variants.

Exploring and exploiting plant cyclic peptides for drug discovery and development.

Ever since the discovery of insulin, natural peptides have become an important resource for therapeutic development. Decades of research has led to the discovery of a long list of peptide drugs with broad applications in clinics, from antibiotics to hypertension treatment to pain management. Many of these US FDA-approved peptide drugs are derived from microorganisms and animals. By contrast, the great potential of plant cyclic peptides as therapeutics remains largely unexplored. These macrocyclic peptides typically have rigid structures, good bioavailability and membrane permeability, making them appealing candidates for drug development and engineering. In this review, we introduce the three major classes of plant cyclic peptides and summarize their potential medical applications. We discuss how we can leverage the genome information of many different plants to quickly search for new cyclic peptides and how we can take advantage of the insights gained from their biosynthetic pathways to transform the process of production and drug development. These recent developments have provided a new angle for exploring and exploiting plant cyclic peptides, and we believe that many more peptide drugs derived from plants are about to come.

MiR-122-5p knockdown protects against APAP-mediated liver injury through up-regulating NDRG3.

MiR-122-5p serves as a novel biomarker for drug-induced liver injury (DILI), but its function in DILI remains unclear. The present study, therefore, explored the function and potential mechanism of miR-122-5p in DILI. Sprague-Dawley (SD) rats were treated with miR-122-5p antagomir, and then DILI was induced in the rats by acetaminophen (APAP). To determine the effect of miR-122-5p on DILI in vivo, liver injury was examined by HE staining and TUNEL assays, and the levels of serum ALT and AST were determined using an automated clinical chemistry analyzer. To further reveal the mechanism of miR-122-5p in DILI, THLE-2 (normal liver cell line) cells were transfected with miR-122-5p mimic and inhibitor, NDRG3, and siNDRG3, and then injured by APAP. The relationship between miR-122-5p and NDRG3 was determined by TargetScan, luciferase reporter assay, and Western blot. The viability and apoptosis of THLE-2 cells were detected by CCK-8 and flow cytometry, respectively. The levels of mRNA and protein in vivo and in vitro were measured by qRT-PCR and Western blot, respectively. APAP induced liver injury and increased the levels of ALT, AST, and miR-122-5p in DILI rats. However, these effects of APAP were attenuated by miR-122-5p antagomir. MiR-122-5p negatively regulated NDRG3 expression. APAP decreased cell viability, apoptosis resistance, and Bcl-w and Bcl-2 levels whereas increased Bax level in THLE-2 cells. However, these effects of APAP on THLE-2 cells were promoted by miR-122-5p up-regulation but inhibited by miR-122-5p knockdown. MiR-122-5p knockdown protects against APAP-mediated liver injury through up-regulating NDRG3.

Dissemination, divergence and establishment of H7N9 influenza viruses in China.

Since 2013 the occurrence of human infections by a novel avian H7N9 influenza virus in China has demonstrated the continuing threat posed by zoonotic pathogens. Although the first outbreak wave that was centred on eastern China was seemingly averted, human infections recurred in October 2013 (refs 3-7). It is unclear how the H7N9 virus re-emerged and how it will develop further; potentially it may become a long-term threat to public health. Here we show that H7N9 viruses have spread from eastern to southern China and become persistent in chickens, which has led to the establishment of multiple regionally distinct lineages with different reassortant genotypes. Repeated introductions of viruses from Zhejiang to other provinces and the presence of H7N9 viruses at live poultry markets have fuelled the recurrence of human infections. This rapid expansion of the geographical distribution and genetic diversity of the H7N9 viruses poses a direct challenge to current disease control systems. Our results also suggest that H7N9 viruses have become enzootic in China and may spread beyond the region, following the pattern previously observed with H5N1 and H9N2 influenza viruses.

Chemical constituents from Lonicera japonica flower buds and their anti-hepatoma and anti-HBV activities.

Three new naturally occurring monoterpenoids, japopenoid A (1), japopenoid B (23) japopenoid C (24), and one new caffeoylquinic acid derivative (28), together with thirty-one known compounds (2-22, 25-27, 29-35), were isolated and identified from the flower buds of Lonicera japonica Thunb. Their structures were determined by extensive 1D and 2D NMR spectroscopic methods, high-resolution mass spectrometry, and the absolute configurations of 1, 23, 24 were determined by comparison of their electronic circular dichroism (ECD) spectrum with literature and theoretical calculation. Structurally, compound 1 is a monoterpenoid featured with an unusual tricyclic skeleton. All compounds (1-35) were evaluated for their cytotoxicities against human liver cancer cell lines (HepG 2 and SMMC-7721). Compound 12 exhibited the most potent activity with IC50 values of 26.54 ±â€¯1.95 and 8.72 ±â€¯1.57 µg/ml against HepG 2 and SMMC-7721, and the IC50 values of compound 13 were 26.54 ±â€¯1.95 and 12.35 ±â€¯1.43 µg/ml, respectively. Western blot results further proved that compound 13 induces hepatoma cell apoptosis via the intrinsic apoptosis pathway. In addition, most terpenoids showed inhibitory activity against HBsAg and HBeAg secretion, and HBV DNA replication. In particular, 25 µg/mlof compound 11 inhibits HBsAg and HBeAg secretion, and HBV DNA replication by 39.39 ±â€¯5.25, 15.64 ±â€¯1.25, and 16.13 ±â€¯4.10% compared to the control (p < 0.05). These results indicated that L. japonica flower buds could be served as functional food for anti-hepatoma and anti-HBV activities.

The genesis and source of the H7N9 influenza viruses causing human infections in China.

A novel H7N9 influenza A virus first detected in March 2013 has since caused more than 130 human infections in China, resulting in 40 deaths. Preliminary analyses suggest that the virus is a reassortant of H7, N9 and H9N2 avian influenza viruses, and carries some amino acids associated with mammalian receptor binding, raising concerns of a new pandemic. However, neither the source populations of the H7N9 outbreak lineage nor the conditions for its genesis are fully known. Using a combination of active surveillance, screening of virus archives, and evolutionary analyses, here we show that H7 viruses probably transferred from domestic duck to chicken populations in China on at least two independent occasions. We show that the H7 viruses subsequently reassorted with enzootic H9N2 viruses to generate the H7N9 outbreak lineage, and a related previously unrecognized H7N7 lineage. The H7N9 outbreak lineage has spread over a large geographic region and is prevalent in chickens at live poultry markets, which are thought to be the immediate source of human infections. Whether the H7N9 outbreak lineage has, or will, become enzootic in China and neighbouring regions requires further investigation. The discovery here of a related H7N7 influenza virus in chickens that has the ability to infect mammals experimentally, suggests that H7 viruses may pose threats beyond the current outbreak. The continuing prevalence of H7 viruses in poultry could lead to the generation of highly pathogenic variants and further sporadic human infections, with a continued risk of the virus acquiring human-to-human transmissibility.

Changes in the Length of the Neuraminidase Stalk Region Impact H7N9 Virulence in Mice.

The neuraminidase stalk of the newly emerged H7N9 influenza virus possesses a 5-amino-acid deletion. This study focuses on characterizing the biological functions of H7N9 with varied neuraminidase stalk lengths. Results indicate that the 5-amino-acid deletion had no impact on virus infectivity or replication in vitro or in vivo compared to that of a virus with a full-length stalk, but enhanced virulence in mice was observed for H7N9 encoding a 19- to 20-amino-acid deletion, suggesting that N9 stalk length impacts virulence in mammals, as N1 stalk length does.

Adjuvant Corticosteroid Treatment in Adults With Influenza A (H7N9) Viral Pneumonia.

OBJECTIVE: To determine the impact of adjuvant corticosteroids administered to patients hospitalized with influenza A (H7N9) viral pneumonia. DESIGN: The effects of adjuvant corticosteroids on mortality were assessed using multivariate Cox regression and a propensity score-matched case-control study. Nosocomial infections and viral shedding were also compared. SETTING: Hospitals with influenza A (H7N9) viral pneumonia patient admission in 84 cities and 16 provinces of Mainland China. PATIENTS: Adolescent and Adult patients aged >14 yr with severe laboratory-confirmed influenza A (H7N9) virus infections were screened from April 2013 to March 2015. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The study population comprised 288 cases who were hospitalized with influenza A (H7N9) viral pneumonia. The median age of the study population was 58 years, 69.8% of the cohort comprised male patients, and 51.4% had at least one type of underlying diseases. The in-hospital mortality was 31.9%. Two hundred and four patients (70.8%) received adjuvant corticosteroids; among them, 193 had hypoxemia and lung infiltrates, 11 had chronic obstructive pulmonary disease, and 11 had pneumonia only. Corticosteroids were initiated within 7 days (interquartile range, 5.0-9.4 d) of the onset of illness and the maximum dose administered was equivalent to 80-mg methylprednisolone (interquartile range, 40-120 mg). The patients were treated with corticosteroids for a median duration of 7 days (interquartile range, 4.0-11.3 d). Cox regression analysis showed that compared with the patients who did not receive corticosteroid, those who received corticosteroid had a significantly higher 60-day mortality (adjusted hazards ratio, 1.98; 95% CI, 1.03-3.79; p = 0.04). Subgroup analysis showed that high-dose corticosteroid therapy (> 150 mg/d methylprednisolone or equivalent) significantly increased both 30-day and 60-day mortality, whereas no significant impact was observed for low-to-moderate doses of corticosteroids (25-150 mg/d methylprednisolone or equivalent). The propensity score-matched case-control analysis showed that the median viral shedding time was much longer in the group that received high-dose corticosteroids (15 d), compared with patients who did not receive corticosteroids (13 d; p = 0.039). CONCLUSIONS: High-dose corticosteroids were associated with increased mortality and longer viral shedding in patients with influenza A (H7N9) viral pneumonia.

Allele-specific induction of IL-1ß expression by C/EBPß and PU.1 contributes to increased tuberculosis susceptibility.

Mycobacterium tuberculosis infection is associated with a spectrum of clinical outcomes, from long-term latent infection to different manifestations of progressive disease. Pro-inflammatory pathways, such as those controlled by IL-1ß, have the contrasting potential both to prevent disease by restricting bacterial replication, and to promote disease by inflicting tissue damage. Thus, the ultimate contribution of individual inflammatory pathways to the outcome of M. tuberculosis infection remains ambiguous. In this study, we identified a naturally-occurring polymorphism in the human IL1B promoter region, which alters the association of the C/EBPß and PU.1 transcription factors and controls Mtb-induced IL-1ß production. The high-IL-1ß expressing genotype was associated with the development of active tuberculosis, the severity of pulmonary disease and poor treatment outcome in TB patients. Higher IL-1ß expression did not suppress the activity of IFN-γ-producing T cells, but instead correlated with neutrophil accumulation in the lung. These observations support a specific role for IL-1ß and granulocytic inflammation as a driver of TB disease progression in humans, and suggest novel strategies for the prevention and treatment of tuberculosis.

HBsAg and HBeAg in the prediction of a clinical response to peginterferon α-2b therapy in Chinese HBeAg-positive patients.

BACKGROUND: This study aimed to evaluate the predictive values of hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) levels in 171 Chinese patients with chronic hepatitis B who received a 48-week course of pegylated interferon alfa-2b therapy at 1.5 mcg/kg. METHODS: HBsAg, HBeAg, and hepatitis B virus (HBV) DNA levels were measured at baseline and weeks 12, 24, 48, and 72. Clinical responses were defined as a combined response (CR, HBeAg seroconversion [sustained response, SR] combined with HBV DNA level <2,000 IU/mL at week 72). The positive predictive value and negative predictive value were calculated for HBsAg alone and/or combined with HBeAg and HBV DNA at weeks 12 and 24. RESULTS: Of 171 patients included, 58 (33.9 %) achieved a SR. Of patients who achieved a SR, 33 (56.9 %) achieved a CR. Totally 19.3 % (33/171) patients achieved CR and 80.7 % (138/171) patients did not. Patients with HBsAg <1500 IU/mL at week 12 had a 47.4 % chance of achieving an off-treatment SR and patients with a HBsAg decrease >1.5 logIU/mL at week 12 had a 54.5 % chance. Patients with HBsAg >20,000 IU/mL at weeks 12 and 24 had a 93.8 and 100.0 % chance, respectively, of not achieving a CR. An HBsAg level or changes at weeks 12 and 24, combined with HBeAg or HBV DNA, increased the chance for a SR and CR. CONCLUSIONS: On-treatment HBsAg quantification, alone or in combination with HBeAg or HBV DNA, predicted off-treatment SR and CR after 48 weeks of PEG-IFNα-2b therapy, and thus, may guide clinicians in making a therapeutic decision to continue or terminate the therapy.

Exploration of novel cellular and serological antigen biomarkers in the ORFeome of Mycobacterium tuberculosis.

Increasing evidence demonstrates that antigen-specific cellular and humoral immunity plays an indispensable role in protection against Mycobacterium tuberculosis infection. Antigen is a key element in the development of a successful diagnostic method and vaccine. However, few antigens are available, and a systemic study on M. tuberculosis ORFeome-based antigen screening is still lacking. In the current study, a genome-wide examination was conducted on high-throughput M. tuberculosis encoding proteins and novel antigens were identified via a comprehensive investigation of serological and antigen-specific cellular responses. The serological immunoglobulin G level of each protein was detected in pooled sera from 200 pulmonary tuberculosis patients by means of semi-quantitative Western blot. Of the 1,250 detected proteins, 29 were present at a higher level relative to the commercialized 38-kDa protein. Furthermore, the top 12 of the 29 proteins had not been previously reported, and their antigenicity was validated in serum from each individual patient. Results confirmed that the 12 proteins displayed nearly identical immunoglobulin G antibody levels in patients with pulmonary and extrapulmonary tuberculosis. Antigen-specific cellular interferon-γ secretion was also evaluated using a cell-based ELISPOT assay. Thirty-four of the proteins were able to induce positive interferon-γ production by peripheral blood mononuclear cells from pulmonary tuberculosis patients as judged by positive (commercial ESAT-6 antigen) and negative controls. The top 4 candidates out of the 34 proteins displayed good accuracy ranging from 50% to 80% compared with the commercial ESAT-6 antigen. Subsequent epitope examination confirmed that a pool of peptides, including a 25aa peptide from Rv1198, demonstrated significant tuberculosis-specific cellular interferon-γ production. Overall, the current study draws significant attention to novel M. tuberculosis antigens, many of which have not been previously reported. This discovery provides a large amount of useful information for the diagnosis of tuberculosis and the development of vaccines to provide protection against tuberculosis.

Expansion of genotypic diversity and establishment of 2009 H1N1 pandemic-origin internal genes in pigs in China.

UNLABELLED: Two-way transmission of influenza viruses between humans and swine has been frequently observed, and the occurrence of the 2009 H1N1 pandemic influenza virus (pdm/09) demonstrated that swine-origin viruses could facilitate the genesis of a pandemic strain. Although multiple introductions to and reassortment in swine of the pdm/09 virus have been repeatedly reported in both Eurasia and the Americas, its long-term impact on the development of swine influenza viruses (SIVs) has not been systematically explored. Our comprehensive evolutionary studies of the complete genomes of 387 SIVs obtained from 2009 to 2012 by influenza virus surveillance in China revealed 17 reassortant genotypes with pdm/09-origin genes. Even though the entire 2009 pandemic virus and its surface genes cannot persist, its internal genes have become established and are now the predominant lineages in pigs in the region. The main persistent pdm/09-origin reassortant forms had at least five pdm/09-origin internal genes, and their surface genes were primarily of European avian-like (EA) or human H3N2-like SIV origin. These findings represent a marked change in the evolutionary patterns and ecosystem of SIVs in China. It is possible that the pdm/09-origin internal genes are in the process of replacing EA or triple-reassortant-like internal genes. These alterations in the SIV gene pool need to be continually monitored to assess changes in the potential for SIV transmission to humans. IMPORTANCE: Shortly after the emergence of the 2009 pandemic H1N1 (pdm/09) influenza virus, it was transmitted from humans to pigs and this continues to occur around the world. Many reassortants between pdm/09-origin viruses and enzootic swine influenza viruses (SIVs) have been detected. However, the long-term impact of pdm/09-origin viruses on the SIV gene pool, which could lead to the generation of influenza viruses with the potential to infect humans, has not been systematically examined. From extensive surveillance of SIVs over a 38-month period in southern China, it was found that although neither complete pdm/09 viruses nor their surface genes could persist in pigs, their internal genes did persist. Over the survey period, these internal genes became predominant, potentially replacing those of the enzootic SIV lineages. The altered diversity of the SIV gene pool needs to be closely monitored for changes in the potential for SIV transmission to humans.

GWAS identifies novel susceptibility loci on 6p21.32 and 21q21.3 for hepatocellular carcinoma in chronic hepatitis B virus carriers.

Genome-wide association studies (GWAS) have recently identified KIF1B as susceptibility locus for hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). To further identify novel susceptibility loci associated with HBV-related HCC and replicate the previously reported association, we performed a large three-stage GWAS in the Han Chinese population. 523,663 autosomal SNPs in 1,538 HBV-positive HCC patients and 1,465 chronic HBV carriers were genotyped for the discovery stage. Top candidate SNPs were genotyped in the initial validation samples of 2,112 HBV-positive HCC cases and 2,208 HBV carriers and then in the second validation samples of 1,021 cases and 1,491 HBV carriers. We discovered two novel associations at rs9272105 (HLA-DQA1/DRB1) on 6p21.32 (OR = 1.30, P = 1.13×10⁻¹9) and rs455804 (GRIK1) on 21q21.3 (OR = 0.84, P = 1.86×10⁻8), which were further replicated in the fourth independent sample of 1,298 cases and 1,026 controls (rs9272105: OR = 1.25, P = 1.71×10⁻4; rs455804: OR = 0.84, P = 6.92×10⁻³). We also revealed the associations of HLA-DRB1*0405 and 0901*0602, which could partially account for the association at rs9272105. The association at rs455804 implicates GRIK1 as a novel susceptibility gene for HBV-related HCC, suggesting the involvement of glutamate signaling in the development of HBV-related HCC.

Tim-3-expressing CD4+ and CD8+ T cells in human tuberculosis (TB) exhibit polarized effector memory phenotypes and stronger anti-TB effector functions.

T-cell immune responses modulated by T-cell immunoglobulin and mucin domain-containing molecule 3 (Tim-3) during Mycobacterium tuberculosis (Mtb) infection in humans remain poorly understood. Here, we found that active TB patients exhibited increases in numbers of Tim-3-expressing CD4(+) and CD8(+) T cells, which preferentially displayed polarized effector memory phenotypes. Consistent with effector phenotypes, Tim-3(+)CD4(+) and Tim-3(+)CD8(+) T-cell subsets showed greater effector functions for producing Th1/Th22 cytokines and CTL effector molecules than Tim-3(-) counterparts, and Tim-3-expressing T cells more apparently limited intracellular Mtb replication in macrophages. The increased effector functions for Tim-3-expressing T cells consisted with cellular activation signaling as Tim-3(+)CD4(+) and Tim-3(+)CD8(+) T-cell subsets expressed much higher levels of phosphorylated signaling molecules p38, stat3, stat5, and Erk1/2 than Tim-3- controls. Mechanistic experiments showed that siRNA silencing of Tim-3 or soluble Tim-3 treatment interfering with membrane Tim-3-ligand interaction reduced de novo production of IFN-γ and TNF-α by Tim-3-expressing T cells. Furthermore, stimulation of Tim-3 signaling pathways by antibody cross-linking of membrane Tim-3 augmented effector function of IFN-γ production by CD4(+) and CD8(+) T cells, suggesting that Tim-3 signaling helped to drive stronger effector functions in active TB patients. This study therefore uncovered a previously unknown mechanism for T-cell immune responses regulated by Tim-3, and findings may have implications for potential immune intervention in TB.

Statil suppresses cancer cell growth and proliferation by the inhibition of tumor marker AKR1B10.

Aldo-keto reductase 1B10 (AKR1B10) is an oncogenic carbonyl reductase that eliminates α,ß-unsaturated carbonyl compounds/lipid peroxides and mediates retinoic acid signaling. Targeted inhibition of AKR1B10 activity is a newly emerging strategy for cancer therapy. This study evaluated the inhibitory activity of a small chemical statil towards AKR1B10 and tested its antiproliferative activity in breast (BT-20) and lung (NCI-H460) cancer cells that express AKR1B10. Experimental results showed that statil inhibited AKR1B10 enzyme activity efficiently, with an IC50 at 0.21±0.06 µmol/l. Exposing BT-20 and NCI-H460 cells to statil and diclofenac, a selective AKR1B10 inhibitor, led to dose-dependent inhibition of cell growth and proliferation and plating efficiency. At higher doses (50 µmol/l or higher), statil induced cell death with apoptotic characteristics, such as DNA fragmentation and Annexin-V staining. Furthermore, statil enhanced the susceptibility of cells to acrolein, an active substrate of AKR1B10. Taken together, these data suggest that statil possesses potent antiproliferative activity by inhibiting AKR1B10 activity.

Chimeric antigen receptor therapy meets mRNA technology.

Genetically engineered immune cells expressing chimeric antigen receptors (CARs) have emerged as a new game changer in cancer immunotherapy. The utility of CAR T cell therapy against hematological malignancies has been validated in clinical practice. Other CAR immune cells are currently under investigation to improve the potency of CAR therapy in solid tumors. As a new class of therapeutic modalities, mRNA-based therapeutics hold enormous potential beyond COVID-19 mRNA vaccines. Arming immune cells with mRNA-encoded CARs represents a new frontier in cancer and beyond, enabling in vivo generation of CAR cells without causing transgene integration. In this review, we summarize recent advances in mRNA-based CAR immunotherapies and highlight their opportunities and challenges for the development of a new generation of living drugs.

Quaternization drives spleen-to-lung tropism conversion for mRNA-loaded lipid-like nanoassemblies.

Background: As the overwhelming majority of advanced mRNA delivery systems are preferentially accumulated in the liver, there is an accelerating growth in the demand for the development of non-liver mRNA delivery platforms. Methods: In this study, we prepared cationic lipid-like nanoassemblies through a N-quaternizing strategy. Their physicochemical properties, in vitro mRNA delivery efficiency, and organ tropism in mice were investigated. Results: Introduction of quaternary ammonium groups onto lipid-like nanoassemblies not only enhances their mRNA delivery performance in vitro, but also completely alters their tropism from the spleen to the lung after intravenous administration in mice. Quaternized lipid-like nanoassemblies exhibit ultra-high specificity to the lung and are predominantly taken up by pulmonary immune cells, leading to over 95% of exogenous mRNA translation in the lungs. Such mRNA delivery carriers are stable even after more than one-year storage at ambient temperature. Conclusions: Quaternization provides an alternative method for design of new lung-targeted mRNA delivery systems without incorporation of targeting ligands, which should extend the therapeutic applicability of mRNA to lung diseases.

Genetic variants in IL1A and IL1B contribute to the susceptibility to 2009 pandemic H1N1 influenza A virus.

BACKGROUND: Host genetic variations may contribute to disease susceptibility of influenza. IL-1A and IL-1B are important inflammatory cytokines that mediate the inflammation and initiate the immune response against virus infection. In this study, we investigated the relationship between single-nucleotide polymorphisms (SNPs) of Interleukin-1A (IL-1A) and Interleukin-1B (IL-1B) and the susceptibility to 2009 pandemic A/H1N1 influenza (A(H1N1)pdm09). 167 patients whom were confirmed with A(H1N1)pdm09 and 192 healthy controls were included in this study. Four SNPs (rs1304037, rs16347, rs17561, rs2071373) in IL1A gene and three SNPs (rs1143623, rs3917345, rs1143627) in IL1B gene were genotyped by using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry platform, and the associations of the genetic variants of IL-1 with susceptibility to A(H1N1)pdm09 were then assessed. RESULTS: The polymorphisms of rs17561 in IL1A gene and rs1143627 in IL1B gene were found to be associated with susceptibility to A(H1N1)pdm09 with P values of 0.003 (OR 2.08, 95% CI 1.27-3.41) and 0.002 (OR 1.62 , 95% CI 1.20-2.18), respectively. However, no significant difference in allelic frequency was observed for other SNPs between cases and controls. CONCLUSIONS: This study provides a new insight into pathogenesis of A(H1N1)pdm09, suggesting that genetic variants of IL-1A and IL-1B may exert a substantial impact on the susceptibility of A(H1N1)pdm09 virus infection.

Emergence and dissemination of a swine H3N2 reassortant influenza virus with 2009 pandemic H1N1 genes in pigs in China.

The 2009 pandemic influenza virus (pdm/09) has been frequently introduced to pigs and has reassorted with other swine viruses. Recently, H3N2 reassortants with pdm/09-like internal genes were isolated in Guangxi and Hong Kong, China. Genetic and epidemiological analyses suggest that these viruses have circulated in swine for some time. This is the first evidence that swine reassortant viruses with pdm/09-like genes may have become established in the field, altering the landscape of human and swine influenza.