The small interferon-induced transmembrane genes and proteins

"Unveiling the genetic symphony: Diversity and expression of chicken IFITM genes in Aseel and Kadaknath breeds"

In this investigation, single nucleotide variants (SNVs) within the chicken interferon-inducible transmembrane protein (chIFITM) genes were explored in Aseel and Kadaknath breeds. Comparative analysis with the GRCg6a reference genome revealed 9 and 16 SNVs in the chIFITM locus for Aseel and Kadaknath breeds, respectively. When referencing the Genome Reference Consortium GRCg7b, Kadaknath exhibited 10 variants, contrasting with none in Aseel. Notably, 17, 8, 2, and 5 SNVs were identified in chIFITM1, chIFITM2, chIFITM3, and chIFITM5 genes, with chIFITM1 showing the highest polymorphism in Kadaknath, featuring 10 intronic variants, including three SNVs (rs16457112, rs16457111, and rs313341707) common to both breeds. Two synonymous exonic variants (g.1817767C > A and g.1819102C > T) were also noted in chIFITM1. Although chIFITM protein sequences were generally conserved, genetic variations clustered predominantly in UTR and intronic regions. Examination of immune response dynamics in live embryos uncovered notable variations in chIFITM gene expression across diverse organs and chicken breeds. Specifically, chIFITM1 mRNA was abundant in cecal tonsils for both breeds and bursa of Aseel (7.61 folds), but it was absent in the heart and lung tissues of both breeds. Conversely, chIFITM3 consistently exhibited heightened expression, particularly in bursa of Aseel (10.23 folds). Whereas mRNA of the chIFITM2 gene was found to be abundant in the heart of Kadaknath (11.03 folds) and lung of both breeds. Furthermore, the expression pattern of chIFITM5 diverged between the two breeds, the heart of Kadaknath chickens showed highest (10.45 folds). The study discovered that breed-specific genetic variants within these genes present a potential pathway for selection and breeding to improve disease resistance in chicken. The observed genetic variation among chicken populations highlights the critical importance of these variants in reinforcing virus resistance, exhibiting applicability across a wide range of breeds.

Unveiling the immunoregulatory role of interferon-induced transmembrane protein 2 through the JAK/STAT3/PDL1 pathway in gastric cancer

Programmed cell death ligand 1 (PDL1) has been implicated in immune evasion in various tumor types. The objective of this investigation was to assess the correlation between metastasis-associated interferon-induced transmembrane protein 2 (IFITM2) and PDL1, and explore their impact on tumor immunity in gastric cancer (GC). The expression of IFITM2 and PDL1 in human GC tissues was initially evaluated using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, as well as immunohistochemistry (IHC). Subsequently, the relationship between IFITM2 and PDL1 was analyzed through Real-time quantitative PCR (RT-qPCR) and western blotting after cell transfection and inhibitor treatment in vitro. The role of IFITM2 and PDL1 in immune killing was further elucidated in both in vitro and in vivo settings. Our study revealed frequent overexpression of IFITM2 and PDL1 in GC. Notably, IFITM2 expression was significantly associated with lymphatic metastasis, clinical stage, and poor survival. Moreover, a positive correlation between PDL1 expression and IFITM2 expression in GC was identified. The activation of tumor-derived IFITM2 was found to enhance PDL1 expression via the JAK/STAT3 pathway in human GC cells (MKN28 and MKN45), leading to apoptosis of Jurkat T cells. Furthermore, IFITM2 induced PDL1 expression in a xenograft mouse model of GC. Based on our findings, we propose that IFITM2 modulates PDL1 expression and tumor immunity through the JAK/STAT3 pathway in GC cells, highlighting the potential of IFITM2 as a therapeutic target for GC immunotherapy.

IFITM3 reduces infectious bursal disease virus proliferation by regulating interferon expression

Interferon-inducible transmembrane protein 3 (IFITM3), a member of the interferon-stimulating factor (ISG) family, has various antiviral functions. Infectious bursal disease virus (IBDV) mainly invades the bursa of Fabricius in chickens, causing a reduction in their immunity and resulting in death from secondary infections. Our previous study found that IBDV infection promotes the expression of chicken IFITM3. However, the role of chicken IFITM3 in IBDV infection remains unknown. To explore this role, the overexpression vector for IFITM3 was constructed and transfected into HD-11 and DF-1 cells. The results showed that the overexpression of IFITM3 significantly reduced IBDV proliferation. While the IBDV proliferation increased when IFITM3 was inhibited by using siRNA. To further explore the mechanism by which IFITM3 reduces IBDV proliferation, the effects of IFITM3 on interferon (IFN) were investigated. Transfecting the constructed IFITM3 vectors into HD-11 and DF-1 cells demonstrated that IFITM3 promoted the expression of IFN-α, IFN-β, and IFN-γ. To investigate the mechanism by which IFITM3 regulates IFN expression, the effects of IFITM3 on IFN production were explored. The results showed that the IKB gene mainly affected the regulatory effects of IFITM3 on IFN. Taken together, IFITM3 may reduce viral proliferation by regulating changes in IFNs, and this process may involve a positive feedback effect of IFITM3 on IFN. IKB plays an important role in the regulation of IFN effects by IFITM3.

Insights into preeclampsia: a bioinformatics approach to deciphering genetic and immune contributions

Background

Preeclampsia (PE) is a global pregnancy concern, characterized by hypertension with an unclear etiology. This study employs Mendelian randomization (MR) and single-cell RNA sequencing (scRNA-seq) to clarify its genetic and molecular roots, offering insights into diagnosis and treatment avenues.

Methods

We integrated PE-specific genome-wide association study (GWAS) data, expression and protein quantitative trait loci (eQTL and pQTL) data, and single-cell data from peripheral blood mononuclear cells (PBMCs). We identified highly variable genes using single-cell information and employed MR to determine potential causality. We also combined pQTL and GWAS data, discerned genes positively associated with PE through scRNA-seq, and leveraged the Enrichr platform to unearth drug-gene interactions.

Results

Our scRNA-seq pinpointed notable cell type distribution variances, especially in T helper cells (Th cells), between PE and control groups. We unveiled 591 highly variable genes and 6 directly PE-associated genes. Although MR revealed correlations with PE risk, pQTL analysis was inconclusive due to data constraints. Using DSigDB, 93 potential therapeutic agents, like Retinoic acid targeting core genes (IFITM3, NINJ1, COTL1, CD69, and YWHAZ), emerged as prospective multi-target treatments.

Conclusion

Utilizing MR and scRNA-seq, this study underscores significant cellular disparities, particularly in Th cells, and identifies crucial genes related to PE. Despite some limitations, these genes have been revealed in PE's underlying mechanism. Potential therapeutic agents, such as Retinoic acid, suggest promising treatment pathways.

Oral administration of recombinant outer membrane protein A-based nanovaccine affords protection against Aeromonas hydrophila in zebrafish

Aeromonas hydrophila, an opportunistic warm water pathogen, has always been a threat to aquaculture, leading to substantial economic losses. Vaccination of the cultured fish would effectively prevent Aeromoniasis, and recent advancements in nanotechnology show promise for efficacious vaccines. Oral delivery would be the most practical and convenient method of vaccine delivery in a grow-out pond. This study studied the immunogenicity and protective efficacy of a nanoparticle-loaded outer membrane protein A from A. hydrophila in the zebrafish model. The protein was over-expressed, purified, and encapsulated using poly lactic-co-glycolic acid (PLGA) nanoparticles via the double emulsion method. The PLGA nanoparticles loaded with recombinant OmpA (rOmpA) exhibited a size of 295 ± 15.1 nm, an encapsulation efficiency of 72.52%, and a polydispersity index of 0.292 ± 0.07. Scanning electron microscopy confirmed the spherical and isolated nature of the PLGA-rOmpA nanoparticles. The protective efficacy in A. hydrophila-infected zebrafish after oral administration of the nanovaccine resulted in relative percentage survival of 77.7. Gene expression studies showed significant upregulation of immune genes in the vaccinated fish. The results demonstrate the usefulness of oral administration of nanovaccine-loaded rOmpA as a potential vaccine since it induced a robust immune response and conferred adequate protection against A. hydrophila in zebrafish, Danio rerio.

The role and mechanism of IFITM1 in developing acquired cisplatin resistance in small cell lung cancer

Platinum-based chemotherapies, historically the cornerstone of first-line treatment for small-cell lung cancer (SCLC), face a major hurdle: the frequent emergence of chemoresistance, notably to cisplatin (CDDP). Current understanding of the mechanisms driving CDDP resistance in SCLC is incomplete. Notably, Interferon inducible transmembrane protein1 (IFITM1) has been identified as a key player in the distant metastasis of SCLC. Analysis of The Cancer Genome Atlas (TCGA) database revealed that IFITM1 expression is markedly elevated in tumor tissues as compared to that from adjacent normal tissues, correlating with a worse prognosis for patients with SCLC. Our research focused on investigating the role of IFITM1 in the acquisition of cisplatin resistance in SCLC. Further clinical sample analysis highlighted a significant increase in IFITM1 levels in SCLC tissues from cisplatin-resistant patients versus those were responsive to CCDP treatment, with similar trends observed in cisplatin-resistant SCLC cells. Crucially, overexpression of IFITM1 reduced the sensitivity of SCLC cells to cisplatin, while silencing IFITM1 enhanced chemosensitivity in cisplatin-resistant strains. Our in vivo studies further confirmed that silencing IFITM1 significantly boosted the efficacy of cisplatin in inhibiting growth of subcutaneous tumors of NCI-H466/CDDP cells (cisplatin-resistant SCLC cells) in a mouse model. Mechanistically, IFITM1 appears to foster cisplatin resistance through activation of the Wnt/β-catenin pathway. In summary, our findings suggest that targeting IFITM1, alongside cisplatin treatment, could offer a promising therapeutic strategy to overcome resistance and improve outcomes for SCLC patients.

Role of interferon-induced transmembrane protein family in cancer progression: a special focus on pancreatic cancer

Human interferon-induced transmembrane protein family (IFITMs) consists of five main proteins. IFITM1, IFITM2, and IFITM3 can be induced by interferon, while IFITM5 and IFITM10 are insensitive to interferon. IFITMs has various functions, including well-researched antiviral effects. As a molecule whose expression is significantly increased by interferon in the immune microenvironment, IFITMs has drawn growing interest in recent years for their role in the cancer progression. Unlike antiviral effects, the role and mechanism of IFITMs in cancer progression have not been clearly studied, especially the role and molecular mechanism of IFITMs in pancreatic cancer are rarely reported in the literature. This article focuses on the role and potential mechanism of IFITMs in pancreatic cancer progression by analyzing the function and mechanism of IFITM1-3 in other cancers and conducting bioinformatics analysis using the databases, so as to provide a new target for pancreatic cancer therapy.

Pro-inflammatory feedback loops define immune responses to pathogenic Lentivirus infection

BACKGROUND

The Lentivirus human immunodeficiency virus (HIV) causes chronic inflammation and AIDS in humans, with variable rates of disease progression between individuals driven by both host and viral factors. Similarly, simian lentiviruses vary in their pathogenicity based on characteristics of both the host species and the virus strain, yet the immune underpinnings that drive differential Lentivirus pathogenicity remain incompletely understood.

METHODS

We profile immune responses in a unique model of differential lentiviral pathogenicity where pig-tailed macaques are infected with highly genetically similar variants of SIV that differ in virulence. We apply longitudinal single-cell transcriptomics to this cohort, along with single-cell resolution cell-cell communication techniques, to understand the immune mechanisms underlying lentiviral pathogenicity.

RESULTS

Compared to a minimally pathogenic lentiviral variant, infection with a highly pathogenic variant results in a more delayed, broad, and sustained activation of inflammatory pathways, including an extensive global interferon signature. Conversely, individual cells infected with highly pathogenic Lentivirus upregulated fewer interferon-stimulated genes at a lower magnitude, indicating that highly pathogenic Lentivirus has evolved to partially escape from interferon responses. Further, we identify CXCL10 and CXCL16 as important molecular drivers of inflammatory pathways specifically in response to highly pathogenic Lentivirus infection. Immune responses to highly pathogenic Lentivirus infection are characterized by amplifying regulatory circuits of pro-inflammatory cytokines with dense longitudinal connectivity.

CONCLUSIONS

Our work presents a model of lentiviral pathogenicity where failures in early viral control mechanisms lead to delayed, sustained, and amplifying pro-inflammatory circuits, which in turn drives disease progression.

Role of IFITM2 in osteogenic differentiation of C3H10T1/2 mesenchymal stem cells

Interferon-inducible transmembrane (IFITM) are a family of small proteins localized to plasma and endolysosomal membranes. Their functions beyond restricting viral entry and replication have been revealed in recent years. IFITM5 is involved in bone mineralization and is an osteogenic cell surface marker. IFITM1 and 3 interact with desmin and myosin, and are involved in myogenic differentiation. This study found upregulation of Ifitm2 during osteogenic differentiation of C3H10T1/2 cells. This positively correlated to the expression of osteogenic differentiation markers Col1a1, Alp, Runx2, and Ocn. Knockdown of Ifitm2 by siRNAs inhibited osteogenic differentiation, calcium deposition, and osteogenic marker expression of C3H10T1/2 cells. The osteoblast transcriptome revealed that knocking down Ifitm2 affected the expression Wnt signaling pathway-related genes, including Wnt family members, their receptors Lrp, Frizzled, and Lgr, and transmembrane molecule Rnf43 that suppresses the Wnt signaling pathway. Luciferase assays indicated enhancement of canonical Wnt signaling pathways by Ifitm2 overexpression. Furthermore, IFITM2 was colocalized in the metaphyseal bone and growth plate of the mouse tibial bone with SP7, a transcription factor essential for osteoblast differentiation and bone formation. These findings reveal a possible novel function and potential mechanisms of Ifitm2 in osteogenic differentiation.

IFITM1 and IFITM3 Proteins Inhibit the Infectivity of Progeny HIV-1 without Disrupting Envelope Glycoprotein Clusters

Human interferon-induced transmembrane (IFITM) proteins inhibit the fusion of a broad spectrum of enveloped viruses, both when expressed in target cells and when present in infected cells. Upon expression in infected cells, IFITMs incorporate into progeny virions and reduce their infectivity by a poorly understood mechanism. Since only a few envelope glycoproteins (Envs) are present on HIV-1 particles, and Env clustering has been proposed to be essential for optimal infectivity, we asked if IFITM protein incorporation modulates HIV-1 Env clustering. The incorporation of two members of the IFITM family, IFITM1 and IFITM3, into HIV-1 pseudoviruses correlated with a marked reduction of infectivity. Super-resolution imaging of Env distribution on single HIV-1 pseudoviruses did not reveal significant effects of IFITMs on Env clustering. However, IFITM3 reduced the Env processing and incorporation into virions relative to the control and IFITM1-containing viruses. These results show that, in addition to interfering with the Env function, IFITM3 restricts HIV-1 Env cleavage and incorporation into virions. The lack of notable effect of IFITMs on Env clustering supports alternative restriction mechanisms, such as modification of the properties of the viral membrane.

Long-Read Sequencing Reveals Rapid Evolution of Immunity- and Cancer-Related Genes in Bats

Bats are exceptional among mammals for their powered flight, extended lifespans, and robust immune systems and therefore have been of particular interest in comparative genomics. Using the Oxford Nanopore Technologies long-read platform, we sequenced the genomes of two bat species with key phylogenetic positions, the Jamaican fruit bat (Artibeus jamaicensis) and the Mesoamerican mustached bat (Pteronotus mesoamericanus), and carried out a comprehensive comparative genomic analysis with a diverse collection of bats and other mammals. The high-quality, long-read genome assemblies revealed a contraction of interferon (IFN)-α at the immunity-related type I IFN locus in bats, resulting in a shift in relative IFN-ω and IFN-α copy numbers. Contradicting previous hypotheses of constitutive expression of IFN-α being a feature of the bat immune system, three bat species lost all IFN-α genes. This shift to IFN-ω could contribute to the increased viral tolerance that has made bats a common reservoir for viruses that can be transmitted to humans. Antiviral genes stimulated by type I IFNs also showed evidence of rapid evolution, including a lineage-specific duplication of IFN-induced transmembrane genes and positive selection in IFIT2. In addition, 33 tumor suppressors and 6 DNA-repair genes showed signs of positive selection, perhaps contributing to increased longevity and reduced cancer rates in bats. The robust immune systems of bats rely on both bat-wide and lineage-specific evolution in the immune gene repertoire, suggesting diverse immune strategies. Our study provides new genomic resources for bats and sheds new light on the extraordinary molecular evolution in this critically important group of mammals.

Evolution of primate interferon-induced transmembrane proteins (IFITMs): a story of gain and loss with a differentiation into a canonical cluster and IFITM retrogenes

Interferon-inducible transmembrane proteins (IFITMs) are a family of transmembrane proteins. The subgroup of immunity-related (IR-)IFITMs is involved in adaptive and innate immune responses, being especially active against viruses. Here, we suggest that IFITMs should be classified as (1) a canonical IFITM gene cluster, which is located on the same chromosome, and (2) IFITM retrogenes, with a random and unique location at different positions within the genome. Phylogenetic analyses of the canonical cluster revealed the existence of three novel groups of primate IFITMs (pIFITM) in the IR-IFITM clade: the prosimian pIFITMs(pro), the new world monkey pIFITMs(nwm) and the old world monkey pIFITMs(owm). Therefore, we propose a new nomenclature: IR-pIFITM1, IR-pIFITM2, IR-pIFITM3, IR-pIFITMnwm, IR-pIFITMowm, and IR-pIFITMpro. We observed divergent evolution for pIFITM5 and pIFITM10, and evidence for concerted evolution and a mechanism of birth-and-death evolution model for the IR-pIFITMs. In contrast, the IFITMs scattered throughout the genomes possessed features of retrogenes retrotransposed by class 1 transposable elements. The origin of the IFITM retrogenes correspond to more recent events. We hypothesize that the transcript of a canonical IFITM3 has been constantly retrotransposed using class 1 transposable elements resulting in the IFITM retro(pseudo)genes. The unique pattern of each species has most likely been caused by constant pseudogenization and loss of the retro(pseudo)genes. This suggests a third mechanism of evolution for the IR-IFITMs in primates, similar to the birth-and-death model of evolution, but via a transposable element mechanism, which resulted in retro(pseudo)genes.

In Vitro Characterization of chIFITMs of Aseel and Kadaknath Chicken Breeds against Newcastle Disease Virus Infection

Newcastle disease (ND) is highly contagious and usually causes severe illness that affects Aves all over the world, including domestic poultry. Depending on the virus's virulence, it can impact the nervous, respiratory, and digestive systems and cause up to 100% mortality. The chIFITM genes are activated in response to viral infection. The current study was conducted to quantify the mRNA of chIFITM genes in vitro in response to ND viral infection. It also examined its ability to inhibit ND virus replication in chicken embryo fibroblast (CEF) cells of the Aseel and Kadaknath breeds. Results from the study showed that the expression of all chIFITM genes was significantly upregulated throughout the period in the infected CEF cells of both breeds compared to uninfected CEF cells. In CEF cells of the Kadaknath breed, elevated levels of expression of the chIFITM3 gene dramatically reduced ND viral growth, and the viral load was 60% lower than in CEF cells of the Aseel breed. The expression level of the chIFITMs in Kadaknath ranged from 2.39 to 11.68 log₂ folds higher than that of control CEFs and was consistently (p < 0.01) higher than Aseel CEFs. Similar to this, theIFN-γ gene expresses strongly quickly and peaks at 13.9 log₂ fold at 48 hpi. Based on these cellular experiments, the Kadaknath breed exhibits the potential for greater disease tolerance than Aseel. However, to gain a comprehensive understanding of disease resistance mechanisms in chickens, further research involving in vivo investigations is crucial.

Ethyl Gallate Inhibits Bovine Viral Diarrhea Virus by Promoting IFITM3 Expression, Lysosomal Acidification and Protease Activity

Bovine viral diarrhea virus (BVDV) is a highly contagious viral disease which causes economic losses to the cattle industry. Ethyl gallate (EG) is a phenolic acid derivative which has various potentials to modulate the host response to pathogens, such as via antioxidant activity, antibacterial activity, inhibition of the production of cell adhesion factors, and so on. This study aimed to evaluate if EG influences BVDV infection in Madin-Darby Bovine Kidney (MDBK) cells, and to understand the antiviral mechanism. Data indicated that EG effectively inhibited BVDV infection by co-treatment and post-treatment in MDBK cells with noncytotoxic doses. In addition, EG suppressed BVDV infection at an early stage of the viral life cycle by blocking entry and replication steps but not viral attachment and release. Moreover, EG strongly inhibited BVDV infection by promoting interferon-induced transmembrane protein 3 (IFITM3) expression, which localized to the cytoplasm. The protein level of cathepsin B was significantly reduced by BVDV infection, whereas with treatment with EG, it was significantly enhanced. The fluorescence intensities of acridine orange (AO) staining were significantly decreased in BVDV-infected cells but increased in EG-treated cells. Finally, Western blot and immunofluorescence analyses demonstrated that EG treatment significantly enhanced the protein levels of autophagy markers LC3 and p62. Chloroquine (CQ) significantly increased IFITM3 expression, and Rapamycin significantly decreased it. Thus, EG may regulate IFITM3 expression through autophagy. Our results showed that EG could have a solid antiviral activity on BVDV replication in MDBK cells via increased IFITM3 expression, lysosomal acidification, protease activity, and regulated autophagy. EG might have value for further development as an antiviral agent.

Systematic Review and Meta-analysis of Peripheral Blood DNA Methylation Studies in Inflammatory Bowel Disease

BACKGROUND AND AIMS

Over the past decade, the DNA methylome has been increasingly studied in peripheral blood of inflammatory bowel disease [IBD] patients. However, a comprehensive summary and meta-analysis of peripheral blood leukocyte [PBL] DNA methylation studies has thus far not been conducted. Here, we systematically reviewed all available literature up to February 2022 and summarized the observations by means of meta-analysis.

METHODS

We conducted a systematic search and critical appraisal of IBD-associated DNA methylation studies in PBL using the biomarker-based cross-sectional studies [BIOCROSS] tool. Subsequently, we performed meta-analyses on the summary statistics obtained from epigenome-wide association studies [EWAS] that included patients with Crohn's disease [CD], ulcerative colitis [UC] and/or healthy controls [HC].

RESULTS

Altogether, we included 15 studies for systematic review. Critical appraisal revealed large methodological and outcome heterogeneity between studies. Summary statistics were obtained from four studies based on a cumulative 552 samples [177 CD, 132 UC and 243 HC]. Consistent differential methylation was identified for 256 differentially methylated probes [DMPs; Bonferroni-adjusted p ≤ 0.05] when comparing CD with HC and 103 when comparing UC with HC. Comparing IBD [CD + UC] with HC resulted in 224 DMPs. Importantly, several of the previously identified DMPs, such as VMP1/TMEM49/MIR21 and RPS6KA2, were consistently differentially methylated across all studies.

CONCLUSION

Methodological homogenization of IBD epigenetic studies is needed to allow for easier aggregation and independent validation. Nonetheless, we were able to confirm previous observations. Our results can serve as the basis for future IBD epigenetic biomarker research in PBL.

Host Cell Restriction Factors Blocking Efficient Vector Transduction: Challenges in Lentiviral and Adeno-Associated Vector Based Gene Therapies

Gene therapy relies on the delivery of genetic material to the patient's cells in order to provide a therapeutic treatment. Two of the currently most used and efficient delivery systems are the lentiviral (LV) and adeno-associated virus (AAV) vectors. Gene therapy vectors must successfully attach, enter uncoated, and escape host restriction factors (RFs), before reaching the nucleus and effectively deliver the therapeutic genetic instructions to the cell. Some of these RFs are ubiquitously expressed in mammalian cells, while others are cell-specific, and others still are expressed only upon induction by danger signals as type I interferons. Cell restriction factors have evolved to protect the organism against infectious diseases and tissue damage. These restriction factors can be intrinsic, directly acting on the vector, or related with the innate immune response system, acting indirectly through the induction of interferons, but both are intertwined. The innate immunity is the first line of defense against pathogens and, as such cells derived from myeloid progenitors (but not only), are well equipped with RFs to detect pathogen-associated molecular patterns (PAMPs). In addition, some non-professional cells, such as epithelial cells, endothelial cells, and fibroblasts, play major roles in pathogen recognition. Unsurprisingly, foreign DNA and RNA molecules are among the most detected PAMPs. Here, we review and discuss identified RFs that block LV and AAV vector transduction, hindering their therapeutic efficacy.

Clinical-Epidemiological Characteristics and IFITM-3 (rs12252) Variant Involvement in HIV-1 Mother-to-Children Transmission Susceptibility in a Brazilian Population

Mother-to-children transmission (MTCT) is the main infection route for HIV-1 in children, and may occur during pregnancy, delivery, and/or postpartum. It is a multifactorial phenomenon, where genetic variants play an important role. This study aims at analyzing the influence of clinical epidemiological characteristics and a variant (rs12252) in interferon-induced transmembrane protein 3 (IFITM-3), a gene encoding an important viral restriction factor, on the susceptibility to HIV-1 mother-to-children transmission (MTCT). A case-control study was performed on 209 HIV-1-infected mothers and their exposed infected (87) and uninfected (122) children from Pernambuco, Brazil. Clinical-epidemiological characteristics are significantly associated with MTCT susceptibility. Transmitter mothers have a significantly lower age at delivery, late diagnosis, deficiency in ART use (pregnancy and delivery), and detectable viral load in the third trimester of pregnancy compared with non-transmitter mothers. Infected children show late diagnosis, vaginal delivery frequency, and tend to breastfeed, differing significantly from uninfected children. The IFITM-3 rs12252-C allele and TC/CC genotypes (dominant model) are significantly more frequent among infected than uninfected children, but the statistical significance does not remain when adjusted for clinical factors. No significant differences are observed between transmitter and non-transmitter mothers in relation to the IFITM-3 variant.

Integrated bioinformatics analysis of IFITM1 as a prognostic biomarker and investigation of its immunological role in prostate adenocarcinoma

Introduction

Prostate adenocarcinoma (PRAD) is a highly aggressive malignancy with high mortality and poor prognosis, and its potential mechanism remains unclear. Our study aimed to identify novel markers for the prognosis of PRAD using bioinformatics technology.

Methods

The GSE32571 dataset was downloaded from the GEO database, and analyzed via the limma R package to identify differentially expressed genes (DEGs) and differentially expressed immune score-related genes (DEISRGs). The immune-related genes (IRGs) were further obtained by overlapping DEISRGs and DEGs, and the core gene was identified via survival analysis. Furthermore, the expression level, prognostic value, and potential functions of the core gene were evaluated via multiple bioinformatics databases.

Results

A total of 301 IRGs were identified from the GSE32571 dataset, and IFITM1 was a down-regulated gene in several types of cancer, including PRAD. Besides, low expression of IFITM1 was associated with a poor prognosis in PRAD. GSEA indicated that the vital pathways of IFITM1-associated genes were mainly enriched in primary immunodeficiency, Th17 cell differentiation, Th1, and Th2 cell differentiation, natural killer cell-mediated cytotoxicity, myeloid dendritic cell activation, regulation of leukocyte activation, etc. Furthermore, IFITM1 was closely correlated with 22 types of tumor-infiltrating immune cells.

Discussion

IFITM1 was a prognostic biomarker for PRAD patients, and it can be acted as a potential immune therapy target in PRAD.

Interferon-induced transmembrane protein 3 (IFITM3) and its antiviral activity

Infections caused by enveloped viruses require fusion with cellular membranes for viral genome entry. Viral entry occurs following an interaction of viral and cellular membranes allowing the formation of fusion pores, by which the virus accesses the cytoplasm. Here, we focus on interferon-induced transmembrane protein 3 (IFITM3) and its antiviral activity. IFITM3 is predicted to block or stall viral fusion at an intermediate state, causing viral propagation to fail. After introducing IFITM3, we describe the generalized lipid membrane fusion pathway and how it can be stalled, particularly with respect to IFITM3, and current questions regarding IFITM3's topology, with specific emphasis on IFITM3's amphipathic α-helix (AAH) ₅₉V-₆₈M, which is necessary for the antiviral activity. We report new hydrophobicity and hydrophobic moment calculations for this peptide and a variety of active site peptides from known membrane-remodeling proteins. Finally, we discuss the effects of posttranslational modifications and localization, how IFITM3's AAH may block viral fusion, and possible ramifications of membrane composition.

IFITM proteins: Understanding their diverse roles in viral infection, cancer, and immunity

Interferon-induced transmembrane proteins (IFITMs) are broad spectrum antiviral factors that inhibit the entry of a wide range of clinically important pathogens including influenza A virus, HIV-1, and Dengue virus. IFITMs are thought to act primarily by antagonizing virus-cell membrane fusion in this regard. However, recent work on these proteins has uncovered novel post-entry viral restriction mechanisms. IFITMs are also increasingly thought to have a role regulating immune responses, including innate antiviral and inflammatory responses as well as adaptive T-cell and B-cell responses. Further, IFITMs may have pathological activities in cancer, wherein IFITM expression can be a marker of therapeutically resistant and aggressive disease courses. In this review, we summarize the respective literatures concerning these apparently diverse functions with a view to identifying common themes and potentially yielding a more unified understanding of IFITM biology.

Antiviral role of IFITM3 in prototype foamy virus infection

BACKGROUND

Foamy viruses (FVs) are retroviruses with unique replication strategies that cause lifelong latent infections in their hosts. FVs can also produce foam-like cytopathic effects in vitro. However, the effect of host cytokines on FV replication requires further investigation. Although interferon induced transmembrane (IFITMs) proteins have become the focus of antiviral immune response research due to their broad-spectrum antiviral ability, it remains unclear whether IFITMs can affect FV replication.

METHOD

In this study, the PFV virus titer was characterized by measuring luciferase activity after co-incubation of PFVL cell lines with the cell culture supernatants (cell-free PFV) or the cells transfected with pcPFV plasmid/infected with PFV (cell-associated PFV). The foam-like cytopathic effects of PFV infected cells was observed to reflect the virus replication. The total RNA of PFV infected cells was extracted, and the viral genome was quantified by Quantitative reverse transcription PCR to detect the PFV entry into target cells.

RESULTS

In the present study, we demonstrated that IFITM1-3 overexpression inhibited prototype foamy virus (PFV) replication. In addition, an IFITM3 knockdown by small interfering RNA increased PFV replication. We further demonstrated that IFITM3 inhibited PFV entry into host cells. Moreover, IFITM3 also reduced the number of PFV envelope proteins, which was related to IFITM3 promoted envelope degradation through the lysosomal pathway.

CONCLUSIONS

Taken together, these results demonstrate that IFITM3 inhibits PFV replication by inhibiting PFV entry into target cells and reducing the number of PFV envelope.

Identification of potential modulators of IFITM3 by in-silico modeling and virtual screening

IFITM3 is a transmembrane protein that confers innate immunity. It has been established to restrict entry of multiple viruses. Overexpression of IFITM3 has been shown to be associated with multiple cancers, implying IFITM3 to be good therapeutic target. The regulation of IFITM3 activity is mediated by multiple post-translational modifications (PTM). In this study, we have modelled the structure of IFITM3, consistent with experimental predictions on its membrane topology. MD simulation in membrane-aqueous environment revealed the stability of the model. Ligand binding sites on the IFITM3 surface were predicted and it was observed that the best site includes important residues involved in PTM and has good druggable score. Molecular docking was performed using FDA approved ligands and natural ligands from Super Natural II database. The ligands were re-ranked by calculating binding free energy. Select docking complexes were simulated again to substantiate the binding between ligand and IFITM3. We observed that known drugs like Eluxadoline and natural products like SN00224572 and Parishin A have good binding affinity against IFITM3. These ligands form persistent interactions with key lysine residues (Lys83, Lys104) and hence can potentially alter the activity of IFITM3. The results of this computational study can provide a starting point for experimental investigations on IFITM3 modulators.

Does the c.-14C>T Mutation in the IFITM5 Gene Provide Identical Phenotypes for Osteogenesis Imperfecta Type V? Data from Russia and a Literature Review

Osteogenesis imperfecta (OI) is a large group of genetically heterogeneous diseases resulting from decreased bone density and an abnormal microarchitecture, which are clinically manifested by abnormal bone fractures. A distinctive clinical feature of this group of diseases is the presence of spontaneous fractures and skeletal deformities. However, the clinical manifestations of different types of OI are characterized by marked polymorphism with variable severity of skeletal and extra-skeletal features. Previous studies have shown that a mutation (c.-14C>T) in the IFITM5 gene is responsible for autosomal dominant OI type V. However, the mutation has a variable expression pattern and marked clinical heterogeneity. In this study, a clinical and genetic analysis of 12 cases with molecularly confirmed OI type V from 12 unrelated families was performed. Significant clinical heterogeneity of the disease with the same molecular defect was detected. In six subjects (50%), there were no classic signs of OI type V (formation of a hyperplastic bone callus, calcification of the interosseous membrane and dislocation of the radial head). In all cases, the mutation occurred de novo.

Emergent Role of IFITM1/3 towards Splicing Factor (SRSF1) and Antigen-Presenting Molecule (HLA-B) in Cervical Cancer

The IFITM restriction factors play a role in cancer cell progression through undefined mechanisms. We investigate new protein-protein interactions for IFITM1/3 in the context of cancer that would shed some light on how IFITM1/3 attenuate the expression of targeted proteins such as HLA-B. SBP-tagged IFITM1 protein was used to identify an association of IFITM1 protein with the SRSF1 splicing factor and transporter of mRNA to the ribosome. Using in situ proximity ligation assays, we confirmed a predominant cytosolic protein-protein association for SRSF1 and IFITM1/3. Accordingly, IFITM1/3 interacted with HLA-B mRNA in response to IFNγ stimulation using RNA-protein proximity ligation assays. In addition, RT-qPCR assays in IFITM1/IFITM3 null cells and wt-SiHa cells indicated that HLA-B gene expression at the mRNA level does not account for lowered HLA-B protein synthesis in response to IFNγ. Complementary, shotgun RNA sequencing did not show major transcript differences between IFITM1/IFITM3 null cells and wt-SiHa cells. Furthermore, ribosome profiling using sucrose gradient sedimentation identified a reduction in 80S ribosomal fraction an IFITM1/IFITM3 null cells compared to wild type. It was partially reverted by IFITM1/3 complementation. Our data link IFITM1/3 proteins to HLA-B mRNA and SRSF1 and, all together, our results begin to elucidate how IFITM1/3 catalyze the synthesis of target proteins. IFITMs are widely studied for their role in inhibiting viruses, and multiple studies have associated IFITMs with cancer progression. Our study has identified new proteins associated with IFITMs which support their role in mediating protein expression; a pivotal function that is highly relevant for viral infection and cancer progression. Our results suggest that IFITM1/3 affect the expression of targeted proteins; among them, we identified HLA-B. Changes in HLA-B expression could impact the presentation and recognition of oncogenic antigens on the cell surface by cytotoxic T cells and, ultimately, limit tumor cell eradication. In addition, the role of IFITMs in mediating protein abundance is relevant, as it has the potential for regulating the expression of viral and oncogenic proteins.

Interferon Control of Human Coronavirus Infection and Viral Evasion: Mechanistic Insights and Implications for Antiviral Drug and Vaccine Development

Recognition of viral infections by various pattern recognition receptors (PRRs) activates an inflammatory cytokine response that inhibits viral replication and orchestrates the activation of adaptive immune responses to control the viral infection. The broadly active innate immune response puts a strong selective pressure on viruses and drives the selection of variants with increased capabilities to subvert the induction and function of antiviral cytokines. This revolutionary process dynamically shapes the host ranges, cell tropism and pathogenesis of viruses. Recent studies on the innate immune responses to the infection of human coronaviruses (HCoV), particularly SARS-CoV-2, revealed that HCoV infections can be sensed by endosomal toll-like receptors and/or cytoplasmic RIG-I-like receptors in various cell types. However, the profiles of inflammatory cytokines and transcriptome response induced by a specific HCoV are usually cell type specific and determined by the virus-specific mechanisms of subverting the induction and function of interferons and inflammatory cytokines as well as the genetic trait of the host genes of innate immune pathways. We review herein the recent literatures on the innate immune responses and their roles in the pathogenesis of HCoV infections with emphasis on the pathobiological roles and therapeutic effects of type I interferons in HCoV infections and their antiviral mechanisms. The knowledge on the mechanism of innate immune control of HCoV infections and viral evasions should facilitate the development of therapeutics for induction of immune resolution of HCoV infections and vaccines for efficient control of COVID-19 pandemics and other HCoV infections.

Interferon-Induced Transmembrane Proteins Inhibit Infection by the Kaposi's Sarcoma-Associated Herpesvirus and the Related Rhesus Monkey Rhadinovirus in a Cell-Specific Manner

The interferon-induced transmembrane proteins (IFITMs) are broad-spectrum antiviral proteins that inhibit the entry of enveloped viruses. We analyzed the effect of IFITMs on the gamma-2 herpesviruses Kaposi's sarcoma-associated herpesvirus (KSHV) and the closely related rhesus monkey rhadinovirus (RRV). We used CRISPR/Cas9-mediated gene knockout to generate A549 cells, human foreskin fibroblasts (HFF), and human umbilical vein endothelial cells (HUVEC) with combined IFITM1/2/3 knockout and identified IFITMs as cell-dependent inhibitors of KSHV and RRV infection in A549 cells and HFF but not HUVEC. IFITM overexpression revealed IFITM1 as the relevant IFITM that inhibits KSHV and RRV infection. Fluorescent KSHV particles did not pronouncedly colocalize with IFITM-positive compartments. However, we found that KSHV and RRV glycoprotein-mediated cell-cell fusion is enhanced upon IFITM1/2/3 knockout. Taken together, we identified IFITM1 as a cell-dependent restriction factor of KSHV and RRV that acts at the level of membrane fusion. Of note, our results indicate that recombinant IFITM overexpression may lead to results that are not representative for the situation at endogenous levels. Strikingly, we observed that the endotheliotropic KSHV circumvents IFITM-mediated restriction in HUVEC despite high IFITM expression, while influenza A virus (IAV) glycoprotein-driven entry into HUVEC is potently restricted by IFITMs even in the absence of interferon. Mechanistically, we found that KSHV colocalizes less with IFITM1 and IFITM2 in HUVEC than in A549 cells immediately after attachment, potentially contributing to the observed difference in restriction. IMPORTANCE IFITM proteins are the first line of defense against infection by many pathogens and may also have therapeutic importance, as they, among other effectors, mediate the antiviral effect of interferons. Neither their function against herpesviruses nor their mechanism of action is well understood. We report here that in some cells but not in, for example, primary umbilical vein endothelial cells, IFITM1 restricts KSHV and RRV and that, mechanistically, this is likely effected by reducing the fusogenicity of the cell membrane. Further, we demonstrate potent inhibition of IAV glycoprotein-driven infection of cells of extrapulmonary origin by high constitutive IFITM expression.

Molecular characterization of type I IFN-induced cytotoxicity in bladder cancer cells reveals biomarkers of resistance

Although anti-tumor activities of type I interferons (IFNs) have been recognized for decades, the molecular mechanisms contributing to clinical response remain poorly understood. The complex functions of these pleiotropic cytokines include stimulation of innate and adaptive immune responses against tumors as well as direct inhibition of tumor cells. In high-grade, Bacillus Calmette-Guérin (BCG)-unresponsive non-muscle-invasive bladder cancer, nadofaragene firadenovec, a non-replicating adenovirus administered locally to express the IFNα2b transgene, embodies a novel approach to deploy the therapeutic activity of type I IFNs while minimizing systemic toxicities. Deciphering which functions of type I IFN are required for clinical activity will bolster efforts to maximize the efficacy of nadofaragene firadenovec and other type I IFN-based therapies, and inform strategies to address resistance. As such, we characterized the phenotypic and molecular response of human bladder cancer cell lines to IFNα delivered in multiple contexts, including adenoviral delivery. We found that constitutive activation of the type I IFN signaling pathway is a biomarker for resistance to both transcriptional response and direct cytotoxic effects of IFNα. We present several genes that discriminate between sensitive and resistant tumor cells, suggesting they should be explored for utility as biomarkers in future clinical trials of type I IFN-based anti-tumor therapies.

Bioinformatics analysis of sequential gene expression profiling after skin and skeletal muscle wound in mice

It is of great value to use bioinformatics methods to screen the core differentially expressed genes (DEGs) at different times after mouse skin and skeletal muscle wound, and to explore the relationship between them and the wound age. To this end, we downloaded the gene expression profiles of GSE140517 and GSE23006 from the NCBI-GEO gene database, used GEO2R online tools and Venn diagrams to screen out DEGs at different times and common-DEGs. The Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) channel analysis were carried out through the DAVID website respectively. Use STRING tool to build a Protein-protein Interaction (PPI) network, and use Cytoscape software to screen out core DEGs. The results showed that 13, 53, 43 and 13 core DEGs were screened out in the 6 h, 12 h, 24 h and common-DEGs group after wound. There were 7 core DEGs (Cxcl2, Cxcl3, Il1b, Ptgs2, Cxcl1, Timp1, Ccl3) in both the different time point and the common DEGs group. Meanwhile, there are 1 core DEGs (Ccl4) specifically expressed in the 6 h, 29 specifically expressed core DEGs (Isg20, Rtp4, Fcgr1, Ifi44, Trim30a, etc.) in the 12 h, and 18 specifically expressed core DEGs (Ccr7, Myd88, Igsf6, Ccr2, Gpsm3, etc.) in the 24 h, there are 6 core DEGs (Ccl4, Ccl7, Saa3, Cxcl5, Ccl2, Lcn2) specifically expressed in the common-DEGs group. The results of GO and KEGG analysis showed that the deterioration and exudation of the inflammatory response were the main cause at 6 h after wound. In addition to inflammation at 12 h and 24 h, the systemic immune response against viral and bacterial infections also gradually increased. In summary, the core DEGs selected in this study have combined characteristics, consistent with the healing function at the corresponding time point, and they are also has specificity and correlation with wound age. Therefore, by detecting the changes in the expression of co-expressed core DEGs at different times after wound, as well as detecting specific expressed DEGs at a specific time point or a specific period of time, it is very promising to provide help for the wound age estimation. However, limited by the GSE140517 gene expression profile in the database, only the difference in gene expression at different times within 24 h after wound was explored, and the research on the late wound age still needs to be further in-depth.

Myxovirus resistance protein A activates type I IFN signaling pathway to inhibit Zika virus replication

Myxovirus resistance protein A(MxA), one of the dynamin superfamily of large guanosine triphosphatase and a classical interferon stimulated gene (ISG) induced by type I interferons (IFNs), plays antiviral role in various virus infections. However, the effect of MxA on Zika virus (ZIKV) infection and its underlying mechanism remain elusive. In this study, we aimed to explore the role of MxA in ZIKV infection and its potential mechanisms. MxA overexpression was achieved by transfection with plasmid. The levels of MxA expression and ZIKV replication were assayed by both qRT-PCR and western blot. The activation status of Jak/STAT signaling pathway was evaluated at three levels: phosphorylation of STAT1 and STAT2(p-STAT1, p-STAT2) (western blot), activity of interferon sensitive response element (ISRE) (dual luciferase reporter gene assay), and the expression levels of ISGs (qRT-PCR). Our results showed that MxA overexpression inhibited ZIKV replication with no effect on virus entry. The expression levels of retinoic acid inducible gene I (RIG-I), melanoma differentiation-associated gene-5(MDA5), Toll-like receptor3(TLR3) and interferon regulatory Factor 3(IRF3), as well as IFNα and IFNβ, were increased in parallel with MxA upregulation. Interestingly, the inhibitory effect of MxA on ZIKV replication was abolished in type I IFN receptor (IFNAR) deficient cells (U5A). These data collectively supported that MxA inhibits ZIKV replication through activation of the type I IFN signaling pathway.

The safety of VASApos presumptive adult ovarian stem cells

Isolation and characterization of presumptive human adult ovarian stem cells (OSC) has broken the long standing dogma of the absence of postnatal neo-oogenesis. Human adult OSC have been immunosorted by antibodies reacting against the RNA helicase VASA and have been reported to engraft into appropriate stem cell niches to promote neo-oogenesis. Analysis of published research, however, questions some of the findings on isolation, characterization, in-vitro self-renewal and clinical safety of the presumptive human adult OSC. In the present study, human VASA^pos embryo-fetal primordial germ cells and presumptive adult OSC are shown to share several pluripotency and early germ cell markers not ascertained in the initial characterization of adult OSC. A new hypothesis is made that the restoration of fertility claimed to result from presumptive human adult OSC may be attributed instead to VASA^pos embryo-fetal primordial germ cell remnants in the adult ovary, or alternatively to earlier VASA^neg germ cells generated by in-vitro de-differentiation of the presumptive OSC. The suggested hypotheses have extensive implications for the practice and safety of adult OSC in the development of new treatments aimed at rescuing the ovarian reserve.

Disrupting interferon-alpha and NF-kappaB crosstalk suppresses IFITM1 expression attenuating triple-negative breast cancer progression

Overexpression of interferon induced transmembrane protein-1 (IFITM1) enhances tumor progression in multiple cancers, but its role in triple-negative breast cancer (TNBC) is unknown. Here, we explore the functional significance and regulation of IFITM1 in TNBC and strategies to target its expression. Immunohistochemistry staining of a tissue microarray demonstrates that IFITM1 is overexpressed in TNBC samples which is confirmed by TCGA analysis. Targeting IFITM1 by siRNA or CRISPR/Cas9 in TNBC cell lines significantly inhibits proliferation, colony formation, and wound healing in vitro. Orthotopic mammary fat pad and mammary intraductal studies reveal that loss of IFITM1 reduces TNBC tumor growth and invasion in vivo. RNA-seq analysis of IFITM1/KO cells reveals significant downregulation of several genes involved in proliferation, migration, and invasion and functional studies identified NF-κB as an important downstream target of IFITM1. Notably, siRNA knockdown of p65 reduces IFITM1 expression and a drug-repurposing screen of FDA approved compounds identified parthenolide, an NFκB inhibitor, as a cytotoxic agent for TNBC and an inhibitor of IFITM1 in vitro and in vivo. Overall, our findings suggest that targeting IFITM1 by suppressing interferon-alpha/NFκB signaling represents a novel therapeutic strategy for TNBC treatment.

Transgenic Chicks Expressing Interferon-Inducible Transmembrane Protein 1 (IFITM1) Restrict Highly Pathogenic H5N1 Influenza Viruses

Mammalian cells utilize a wide spectrum of pathways to antagonize the viral replication. These pathways are typically regulated by antiviral proteins and can be constitutively expressed but also exacerbated by interferon induction. A myriad of interferon-stimulated genes (ISGs) have been identified in mounting broad-spectrum antiviral responses. Members of the interferon-induced transmembrane (IFITM) family of proteins are unique among these ISGs due to their ability to prevent virus entry through the lipid bilayer into the cell. In the current study, we generated transgenic chickens that constitutively and stably expressed chicken IFITM1 (chIFITM1) using the avian sarcoma-leukosis virus (RCAS)-based gene transfer system. The challenged transgenic chicks with clinical dose 10⁴ egg infective dose 50 (EID₅₀) of highly pathogenic avian influenza virus (HPAIV) subtype H5N1 (clade 2.2.1.2) showed 100% protection and significant infection tolerance. Although challenged transgenic chicks displayed 60% protection against challenge with the sub-lethal dose (EID₅₀ 10⁵), the transgenic chicks showed delayed clinical symptoms, reduced virus shedding, and reduced histopathologic alterations compared to non-transgenic challenged control chickens. These finding indicate that the sterile defense against H5N1 HPAIV offered by the stable expression of chIFITM1 is inadequate; however, the clinical outcome can be substantially ameliorated. In conclusion, chIFITM proteins can inhibit influenza virus replication that can infect various host species and could be a crucial barrier against zoonotic infections.

Integrative overview of IFITMs family based on Bioinformatics analysis

Human interferon-induced transmembrane proteins (IFITMs) family is a multi-functional biomacromolecule family playing a critical role in various physiological processes, such as, antiviral immunity, tumor suppression, and bone formation. Although there are many studies proving that a subset of tumors strongly links to the changes of IFITMs, the link between different IFITMs mutant types and diverse tumors has not been studied thoroughly. To investigate the law of expression among IFITMs internal members and the linking of IFITMs mutant types and cancers, online databases were used to pool together relevant data for bioinformatics analysis. Here, we summarize mutations, expression, and functions of human IFITMs, analyze diverse expression levels of IFITMs in physiological and pathological tissues, predict protein-protein interaction (PPI) networks, and target miRNAs and relevant signaling pathways of IFITMs. The results show that IFITM1, IFITM2, and IFITM3 have similar motif pattern constructions and physiological functions, while IFITM5 and IFITM10 show far diversity from them. Particularly, IFITM1-3, in conjunction with interacting proteins, is strongly related to development and overall survival rates of a portion of cancers, including renal cancer and uveal melanoma (UVM). This trait may make IFITM1-3 become a prognostic marker of cancers. Meanwhile, hsa_circ_0116375 has been found as the common circRNA for IFITM2, IFITM3, IFITM5, and IFITM10.

Deciphering the Roles of IFITM1 in Tumors

Interferon (IFN)-induced transmembrane protein 1 (IFITM1), a member of the IFN-induced transmembrane protein family, is reported to be highly expressed in tumor tissues as well as cancer cell lines, and it is an independent prognostic biomarker for patients with certain tumor types, such as gallbladder carcinoma, esophageal adenocarcinoma, colorectal cancer, and gastric cancer. Moreover, overexpression of IFITM1 promotes tumor cell proliferation, invasion, metastasis, angiogenesis, and therapeutic resistance, including endocrine therapy, chemotherapy, and radiotherapy resistance. Due to these diverse functions of IFITM1 in tumors, targeting IFITM1 may provide a novel strategy for cancer treatment and be highly desirable to improve cancer patient outcomes. Herein, we decipher the role of IFITM1 in cancer in detail.

Ferret Interferon (IFN)-Inducible Transmembrane Proteins Are Upregulated by both IFN-α and Influenza Virus Infection

The current fears of a future influenza pandemic have resulted in an increased emphasis on the development and testing of novel therapeutic strategies against the virus. Fundamental to this is the ferret model of influenza infection, which is critical in examining pathogenesis and treatment. Nevertheless, a precise evaluation of the efficacy of any treatment strategy in ferrets is reliant on understanding the immune response in this model. Interferon-inducible transmembrane proteins (IFITMs) are interferon-stimulated proteins shown to be critically important in the host immune response against viral infections. These proteins confer intrinsic innate immunity to pH-dependent viruses such as influenza viruses and can inhibit cytosolic entry of such viruses to limit the severity of infection following interferon upregulation. Mutations in IFITM genes in humans have been identified as key risk factors for worsened disease progression, particularly in the case of avian influenza viruses such as H7N9. While the IFITM genes of humans and mice have been well characterized, no studies have been conducted to classify the IFITM locus and interferon-driven upregulation of IFITMs in ferrets. Here, we show the architecture of the ferret IFITM locus and its synteny to the IFITM locus of other mammalian and avian species. Furthermore, we show that ferret IFITM1, -2, and -3 are functionally responsive to both interferon-α (IFN-α) and influenza virus stimulation. Thus, we show that ferret IFITMs exhibit interferon-stimulated properties similar to those shown in other species, furthering our knowledge of the innate immune response in the ferret model of human influenza virus infections. IMPORTANCE IFITM proteins can prevent the entry of several pH-dependent viruses, including high-consequence viruses such as HIV, influenza viruses, and SARS-coronaviruses. Mutations in these genes have been associated with worsened disease outcomes with mutations in their IFITM genes, highlighting these genes as potential disease risk factors. Ferrets provide a valuable tool to model infectious diseases; however, there is a critical shortage of information regarding their interferon-stimulated genes. We identified the putative ferret IFITM genes and mapped their complete gene locus. Thus, our study fills a critical gap in knowledge and supports the further use of the ferret model to explore the importance of IFITMs in these important diseases.

Membrane Interference Against HIV-1 by Intrinsic Antiviral Factors: The Case of IFITMs

HIV-1 is a complex retrovirus that is adapted to replicate in cells of the immune system. To do so, HIV-1, like other viruses, developed strategies to use several cellular processes to its advantage, but had also to come to terms with an arsenal of cellular innate defense proteins, or antiviral factors, that target more or less efficiently, virtually every step of the virus replicative cycle. Among antiviral restriction factors, the family of interferon-induced transmembrane proteins (IFITMs) has emerged as a crucial component of cellular innate defenses for their ability to interfere with both early and late phases of viral replication by inhibiting cellular and viral membranes fusion. Here, we review the enormous advances made since the discovery of IFITMs as interferon-regulated genes more than thirty years ago, with a particular focus on HIV-1 and on the elements that modulate its susceptibility or resistance towards members of this family. Given the recent advances of the field in the elucidation of the mechanism of IFITM inhibition and on the mechanism(s) of viral resistance, we expect that future years will bring novel insights into the definition of the multiple facets of IFITMs and on their possible use for novel therapeutical approaches.

Crosstalk Between SUMO and Ubiquitin-Like Proteins: Implication for Antiviral Defense

Interferon (IFN) is a crucial first line of defense against viral infection. This cytokine induces the expression of several IFN-Stimulated Genes (ISGs), some of which act as restriction factors. Upon IFN stimulation, cells also express ISG15 and SUMO, two key ubiquitin-like (Ubl) modifiers that play important roles in the antiviral response. IFN itself increases the global cellular SUMOylation in a PML-dependent manner. Mass spectrometry-based proteomics enables the large-scale identification of Ubl protein conjugates to determine the sites of modification and the quantitative changes in protein abundance. Importantly, a key difference amongst SUMO paralogs is the ability of SUMO2/3 to form poly-SUMO chains that recruit SUMO ubiquitin ligases such RING finger protein RNF4 and RNF111, thus resulting in the proteasomal degradation of conjugated substrates. Crosstalk between poly-SUMOylation and ISG15 has been reported recently, where increased poly-SUMOylation in response to IFN enhances IFN-induced ISGylation, stabilizes several ISG products in a TRIM25-dependent fashion, and results in enhanced IFN-induced antiviral activities. This contribution will highlight the relevance of the global SUMO proteome and the crosstalk between SUMO, ubiquitin and ISG15 in controlling both the stability and function of specific restriction factors that mediate IFN antiviral defense.

Evidence of a dysregulated vitamin D endocrine system in SARS-CoV-2 infected patient's lung cells

Although a defective vitamin D endocrine system has been widely suspected to be associated in SARS-CoV-2 pathobiology, the status of the vitamin D endocrine system and vitamin D-modulated genes in lung cells of patients infected with SARS-CoV-2 remains unknown. To understand the significance of the vitamin D endocrine system in SARS-CoV-2 pathobiology, computational approaches were applied to transcriptomic datasets from bronchoalveolar lavage fluid (BALF) cells of such patients or healthy individuals. Levels of vitamin D receptor, retinoid X receptor, and CYP27A1 in BALF cells of patients infected with SARS-CoV-2 were found to be reduced. Additionally, 107 differentially expressed, predominantly downregulated genes, as potentially modulated by vitamin D endocrine system, were identified in transcriptomic datasets from patient's cells. Further analysis of differentially expressed genes provided eight novel genes with a conserved motif with vitamin D-responsive elements, implying the role of both direct and indirect mechanisms of gene expression by the dysregulated vitamin D endocrine system in SARS-CoV-2-infected cells. Protein-protein interaction network of differentially expressed vitamin D-modulated genes were enriched in the immune system, NF-κB/cytokine signaling, and cell cycle regulation as top predicted pathways that might be affected in the cells of such patients. In brief, the results presented here povide computational evidence to implicate a dysregulated vitamin D endocrine system in the pathobiology of SARS-CoV-2 infection.

pH-Controlled Release of Antigens Using Mesoporous Silica Nanoparticles Delivery System for Developing a Fish Oral Vaccine

The development of effective vaccines and delivery systems in aquaculture is a long-term challenge for controlling emerging and reemerging infections. Cost-efficient and advanced nanoparticle vaccines are of tremendous applicability in prevention of infectious diseases of fish. In this study, dihydrolipoamide dehydrogenase (DLDH) antigens of Vibrio alginolyticus were loaded into mesoporous silica nanoparticles (MSN) to compose the vaccine delivery system. Hydroxypropyl methylcellulose phthalate (HP55) was coated to provide protection of immunogen. The morphology, loading capacity, acid-base triggered release were characterized and the toxicity of nanoparticle vaccine was determined in vitro. Further, the vaccine immune effects were evaluated in large yellow croaker via oral administration. In vitro studies confirmed that the antigen could be stable in enzymes-rich artificial gastric fluid and released under artificial intestinal fluid environment. In vitro cytotoxicity assessment demonstrated the vaccines within 120 μg/ml have good biocompatibility for large yellow croaker kidney cells. Our data confirmed that the nanoparticle vaccine in vivo could elicit innate and adaptive immune response, and provide good protection against Vibrio alginolyticus challenge. The MSN delivery system prepared may be a potential candidate carrier for fish vaccine via oral administration feeding. Further, we provide theoretical basis for developing convenient, high-performance, and cost-efficient vaccine against infectious diseases in aquaculture.

Age-Related Differences in Molecular Profiles for Immune Checkpoint Blockade Therapy

Immune checkpoint blockade (ICB) therapies have significantly improved the prognosis and shown considerable promise for cancer therapy; however, differences in ICB treatment efficacy between the elderly and young are unknown. We analyzed the studies enrolled in the meta-analysis using the deft approach, and found no difference in efficacy except melanoma patients receiving anti–PD-1 therapy. Similarly, higher treatment response rate and more favorable prognosis were observed in elderly patients in some cancer types (e.g., melanoma) with data from published ICB treatment clinical trials. In addition, we comprehensively compared immunotherapy-related molecular profiles between elderly and young patients from public trials and The Cancer Genome Atlas (TCGA), and validated these findings in several independent datasets. We discovered a divergent age-biased immune profiling, including the properties of tumors (e.g., tumor mutation load) and immune features (e.g., immune cells), in a pancancer setting across 27 cancer types. We believe that ICB treatment efficacy might vary depending on specific cancer types and be determined by both the tumor internal features and external immune microenvironment. Considering the high mutational properties in elderly patients in many cancer types, modulating immune function could be beneficial to immunotherapy in the elderly, which requires further investigation.

Identification of IFN-Induced Transmembrane Protein 1 With Prognostic Value in Pancreatic Cancer Using Network Module-Based Analysis

Despite improvements reported in diagnosis and treatments in recent decades, pancreatic cancer is still characterized by poor prognosis and low survival rate among solid tumors. Intensive interests have grown in exploring novel predictive biomarkers, aiming to enhance the efficiency in early detection and treatment prognosis. In this study, we identified the differentially expressed genes (DEGs) in pancreatic cancer by analyzing five gene expression profiles and established the functional modules according to the functional interaction (FI) network between the DEGs. A significant upregulation of the selected DEG, interferon (IFN)-induced transmembrane protein 1 (IFITM1), was evaluated in several bioinformatics online tools and verified with immunohistochemistry staining from samples of 90 patients with pancreatic cancer. Prognostic data showed that high expression of IFITM1 associated with poor survival, and multivariate Cox regression analysis showed IFITM1 was one of the independent prognostic factors for overall survival. Meanwhile, significant correlations of the expression of IFITM1 and the infiltration of immune cells were found by TIMER. Furthermore, a higher level of IFITM1 was assessed in pancreatic cancer cell lines compared to normal human pancreatic duct epithelial cells, and silencing IFITM1 in tumor cells remarkedly inhibited cancer tumorigenicity. Collectively, our findings suggested that IFITM1 might have promising utility for pancreatic cancer.

Mammalian and Avian Host Cell Influenza A Restriction Factors

The threat of a new influenza pandemic is real. With past pandemics claiming millions of lives, finding new ways to combat this virus is essential. Host cells have developed a multi-modular system to detect incoming pathogens, a phenomenon called sensing. The signaling cascade triggered by sensing subsequently induces protection for themselves and their surrounding neighbors, termed interferon (IFN) response. This response induces the upregulation of hundreds of interferon-stimulated genes (ISGs), including antiviral effectors, establishing an antiviral state. As well as the antiviral proteins induced through the IFN system, cells also possess a so-called intrinsic immunity, constituted of antiviral proteins that are constitutively expressed, creating a first barrier preceding the induction of the interferon system. All these combined antiviral effectors inhibit the virus at various stages of the viral lifecycle, using a wide array of mechanisms. Here, we provide a review of mammalian and avian influenza A restriction factors, detailing their mechanism of action and in vivo relevance, when known. Understanding their mode of action might help pave the way for the development of new influenza treatments, which are absolutely required if we want to be prepared to face a new pandemic.

Interferon-Inducible Transmembrane Protein 3-Containing Exosome as a New Carrier for the Cell-to-Cell Transmission of Anti-Brucella Activity

Exosomes are small extracellular vesicles that are released from cells and that function in intercellular communication. Recently, interferon-inducible transmembrane protein 3 (IFITM3) has been identified as a highly effective anti-intracellular pathogen protein that can inhibit the invasion of a wide range of pathogenic microorganisms. However, whether Brucella infection induces secretion of exosomes and whether these exosomes contain IFITM3 protein remain unknown. Here, we focused on the immune function of extracellular IFITM3 protein in the process of Brucella infection. This study is the first to show that Brucella melitensis strain M5 (Brucella M5) can stimulate macrophages to secrete large amounts of exosomes. Most importantly, we identified exosomes from Brucella M5-infected cells that were rich in molecules of IFITM3, and these exosomes could transmit the IFITM3 from one cell to another, thereby effectively inhibiting the intracellular survival of Brucella. Moreover, immunization with exosomes carrying IFITM3 decreased mouse spleen tissue damage and spleen colony forming unit (CFU), leading to the establishment of an anti-Brucella state in mice. In conclusion, our findings provide new insights into the anti-Brucella mechanism of IFITM3-containg exosomes, thus providing a theoretical foundation for systematic elaboration of the mechanisms of Brucella infection and host immunity. The results provide new ideas for the development of candidate vaccines for Brucella.

Interferon-Induced Transmembrane Protein 3 Expression Upregulation Is Involved in Progression of Hepatocellular Carcinoma

Purpose

Interferon-induced transmembrane protein 3 (IFITM3) is a key signaling molecule regulating cell growth in some tumors, but its function and mechanism in hepatocellular carcinoma (HCC) remain unknown. Our study investigated the relationship between the expression of IFITM3 and HCC development. Material and Methods. IFITM3 expression was identified via multiple gene expression databases and investigated in HCC tissue samples. Then, PLC/PRF/5 cells were transfected with lentivirus to knock down and overexpress the expression of IFITM3. IFITM3 expression, cell proliferation, and migration were detected by qRT-PCR, western blotting, QuantiGene Plex 2.0 assay, immunohistochemistry, CCK-8, and wound healing tests. RNA-seq technology identified the PI3K/AKT/mTOR pathway as an IFITM3-related signaling pathway for investigation.

Results

IFITM3 expression was higher in HCC tissues than in adjacent normal tissues, and the level of IFITM3 was higher in HCC tissues with low differentiation and metastatic potential than in those with high/medium differentiation and without metastatic potential. A higher RNA level of IFITM3 was found in samples with IFITM3 rs12252-CC genotype rather than the TT genotype. Knockdown of IFITM3 in PLC/PRF/5 cells inhibited cell proliferation and migration, blocked the expression of the PI3K/AKT/mTOR signaling pathway, and decreased the expression of vimentin. The results were opposite with the overexpression of IFITM3.

Conclusion

Upregulation of IFITM3 plays a role in the development of HCC. Possibly through regulating HCC cell proliferation and migration, these effects are associated with the PI3K/AKT/mTOR signaling pathway. Upregulation of IFITM3 is also associated with the IFITM3 rs12252-CC genotype.

Human Interferon Inducible Transmembrane Protein 3 (IFITM3) Inhibits Influenza Virus A Replication and Inflammation by Interacting with ABHD16A

Studies have shown that human interferon inducible transmembrane protein (hIFITMs) family proteins have broad-spectrum antiviral capabilities. Preliminary studies in our laboratory have tentatively proved that hIFITMs have the effect of inhibiting influenza viruses. In order to further study its mechanism and role in the occurrence and development of influenza A, relevant studies have been carried out. Fluorescence quantitative polymerase chain reaction (PCR) detection technology was used to observe the effect of hIFITM3 on the replication of influenza A virus (IVA) and the interaction with hABHD16A. In HEK293 cells, overexpression of hIFITM3 protein significantly inhibited the replication of IVA at 24 h, 48 h, and 72 h; yeast two-hybrid experiment proved that hIFITM3 interacts with hABHD16A; laser confocal microscopy observations showed that hIFITM3 and hABHD16A colocalized in the cell membrane area; the expression level of inflammation-related factors in cells overexpressing hIFITM3 or hABHD16A was detected by fluorescence quantitative PCR, and the results showed that the mRNA levels of interleukin- (IL-) 1β, IL-6, IL-10, tumor necrosis factor- (TNF-) α, and cyclooxygenase 2 (COX2) were significantly increased. But when hIFITM3/hABHD16A was coexpressed, the mRNA expression levels of these cytokines were significantly reduced except COX2. When influenza virus infected cells coexpressing hIFITM3/hABHD16A, the expression level of inflammatory factors decreased compared with the control group, indicating that hIFITM3 can play an important role in regulating inflammation balance. This study confirmed that hIFITM3 has an effect of inhibiting IVA replication. Furthermore, it was found that hIFITM3 interacts with hABHD16A, following which it can better inhibit the replication of influenza virus and the inflammatory response caused by the disease process.

Role of the Host Genetic Susceptibility to 2009 Pandemic Influenza A H1N1

Influenza A virus (IAV) is the most common infectious agent in humans, and infects approximately 10-20% of the world's population, resulting in 3-5 million hospitalizations per year. A scientific literature search was performed using the PubMed database and the Medical Subject Headings (MeSH) "Influenza A H1N1" and "Genetic susceptibility". Due to the amount of information and evidence about genetic susceptibility generated from the studies carried out in the last influenza A H1N1 pandemic, studies published between January 2009 to May 2020 were considered; 119 papers were found. Several pathways are involved in the host defense against IAV infection (innate immune response, pro-inflammatory cytokines, chemokines, complement activation, and HLA molecules participating in viral antigen presentation). On the other hand, single nucleotide polymorphisms (SNPs) are a type of variation involving the change of a single base pair that can mean that encoded proteins do not carry out their functions properly, allowing higher viral replication and abnormal host response to infection, such as a cytokine storm. Some of the most studied SNPs associated with IAV infection genetic susceptibility are located in the FCGR2A, C1QBP, CD55, and RPAIN genes, affecting host immune responses through abnormal complement activation. Also, SNPs in IFITM3 (which participates in endosomes and lysosomes fusion) represent some of the most critical polymorphisms associated with IAV infection, suggesting an ineffective virus clearance. Regarding inflammatory response genes, single nucleotide variants in IL1B, TNF, LTA IL17A, IL8, IL6, IRAK2, PIK3CG, and HLA complex are associated with altered phenotype in pro-inflammatory molecules, participating in IAV infection and the severest form of the disease.

Malignancy and IFITM3: Friend or Foe?

The prevalence and incidence of cancers has risen over the last decade. Available treatments have improved outcomes, yet mortality and morbidity remain high, creating an urgent demand for personalized and new therapy targets. Interferon induced transmembrane protein (IFITM3) is highly expressed in cancers and is a marker of poor prognosis. In this review, we discuss recent advances in IFITM3 biology, the regulatory pathways, and its function within cancer as part of immunity and maintaining stemness. Overexpression of IFITM3 is likely an indirect effect of ongoing inflammation, immune and cancer epithelial-to-mesenchymal (EMT) related pathways i.e., interferons, TGF-β, WNT/β-catenin, etc. However, IFITM3 also influences tumorigenic phenotypes, such as cell proliferation, migration and invasion. Furthermore, IFITM3 plays a key role in cancer growth and maintenance. Silencing of IFITM3 reduces these phenotypes. Therefore, targeting of IFITM3 will likely have implications for potential cancer therapies.

Current Progress on Host Antiviral Factor IFITMs

Host antiviral factor interferon-induced transmembrane proteins (IFITMs) are a kind of small-molecule transmembrane proteins induced by interferon. Their broad-spectrum antiviral activity and unique ability to inhibit viral invasion have made them a hot molecule in antiviral research in recent years. Since the first demonstration of their natural ability to resist viral infection in 1996, IFITMs have been reported to limit a variety of viral infections, including some major pathogens that seriously endanger human health and social stability, such as influenza A, Ebol, severe acute respiratory syndrome, AIDS, and Zika viruses, etc. Studies show that IFITMs mainly exert antiviral activity during virus entry, specifically interfering with the fusion of the envelope and the endosome membrane or forming fusion micropores to block the virus from entering the cytoplasm. However, their specific mechanism is still unclear. This article mainly reviews the research progress in the structure, evolution, function, and mechanism of IFITMs, which may provide a theoretical basis for clarifying the molecular mechanism of interaction between the molecules and viruses and the research and development of new antiviral drugs based on IFITMs.

DOCK8 is essential for LFA-1-dependent positioning of T follicular helper cells in germinal centers

T follicular helper (Tfh) cell migration into germinal centers (GCs) is essential for the generation of GC B cells and antibody responses to T cell-dependent (TD) antigens. This process requires interactions between lymphocyte function-associated antigen 1 (LFA-1) on Tfh cells and ICAMs on B cells. The mechanisms underlying defective antibody responses to TD antigens in DOCK8 deficiency are incompletely understood. We show that mice selectively lacking DOCK8 in T cells had impaired IgG antibody responses to TD antigens, decreased GC size, and reduced numbers of GC B cells. However, they developed normal numbers of Tfh cells with intact capacity for driving B cell differentiation into a GC phenotype in vitro. Notably, migration of DOCK8-deficient T cells into GCs was defective. Following T cell receptor (TCR)/CD3 ligation, DOCK8-deficient T cells had impaired LFA-1 activation and reduced binding to ICAM-1. Our results therefore indicate that DOCK8 is important for LFA-1-dependent positioning of Tfh cells in GCs, and thereby the generation of GC B cells and IgG antibody responses to TD antigen.