Search Results (289)

CDK4/6 inhibitors exert effective anti-tumor effects by blocking the cell cycle and, as a result, have become vital in the systemic treatment of malignant tumors. Previous research has indicated that CDK4/6 inhibitors not only exert effects on the cell cycle but also have regulatory roles in tumor immunity, although the research findings are controversial. This study comprehensively summarizes the molecular mechanisms by which CDK4/6 inhibitors activate or suppress anti-tumor immunity and reveals the dual effects of CDK4/6 inhibitors on influencing interferon signaling, mediating senescence, and altering certain immune cells. In addition, the results of clinical trials of CDK4/6 inhibitors combined with immunotherapy are thought-provoking, with the severe adverse events that occur after treatment being the main factor affecting their therapeutic effect. Therefore, the future direction of this combined treatment strategy deserves further exploration. Full article

Arsenic, a ubiquitous metalloid, is commonly found in surface waters; as well as serious human health issues, it also induces systemic diseases and carcinogenesis upon chronic exposure. To better understand how arsenic potentially alters the immune system, it is important to study its effects on macrophage polarization. Micro-RNA plays an epigenetic regulatory role in organisms. The miR-125 family regulates macrophage polarization and tumorigenesis, yet its role in arsenic-induced macrophage polarization remains unexplored. This study investigated the mechanism of sodium arsenite (NaAsO₂)-driven macrophage polarization via miR-125a-5p. In vivo, rats exposed to 10 or 50 mg/L NaAsO₂ for 12 weeks exhibited elevated M2 markers (CD206, Arg1) and reduced M1 markers (iNOS, IL-1β, TNF-α) in liver and bladder tissues. In vitro, THP-1-derived macrophages treated with NaAsO₂ (2–8 μM) for 48 h showed dose-dependent M2 polarization, marked by upregulated CD206, Arg1, and IL-10. Flow cytometry results show that the proportion of M2/M1-type cells has increased significantly. Notably, NaAsO₂ suppressed miR-125a-5p expression and elevated interferon regulatory factor 4 (IRF4), a predicted target of miR-125a-5p. Overexpression of miR-125a-5p reversed NaAsO₂-induced M2 polarization by inhibiting IRF4, thereby reducing M2 markers and restoring M1-associated proteins. These findings reveal that NaAsO₂ promotes M2 macrophage polarization through the miR-125a-5p/IRF4 axis, highlighting a novel epigenetic mechanism in arsenic-associated tumor microenvironments and immune dysfunction. This study provides critical insights into targeting miR-125a-5p as a therapeutic strategy. Full article

Mastitis is a common mammary gland disease in mammals that severely impairs lactation function, with Staphylococcus aureus (S. aureus) being the primary pathogenic bacterium. However, the molecular mechanisms underlying S. aureus-induced mastitis in sheep remain incompletely elucidated. This study employed RNA sequencing (RNA-SEq) technology to systematically analyze the dynamic transcriptomic characteristics of mammary tissue in small-tailed sheep (SHT) after S. aureus infection, aiming to clarify the molecular regulatory mechanism of the host immune response and its relationship with the occurrence of mastitis. Twelve lactating STH were selected to establish an S. aureus-induced mastitis model. Blood, milk, and tissue samples were collected at 0, 24, 48, and 72 h post-infection (hpi). The infected sheep exhibited typical mastitis symptoms, including exacerbated breast swelling, reduced milk yield, elevated udder temperature, and darker, more viscous milk. Hematoxylin–eosin (HE) staining revealed significant pathological changes over time, such as stromal hyperplasia, extensive inflammatory cell infiltration, severe necrosis and sloughing of mammary epithelial cells, and compromised tissue integrity. RNA-Seq analysis identified 1299 differentially expressed genes (DEGs), among which 75 core genes maintained stable expression throughout the infection time (24 hpi, 48 hpi, and 72 hpi). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated that these DEGs were associated with metabolic processes, protein binding, Toll-like receptor signaling, and the NF-κB pathway. The PPI network analysis identified core hub genes including PTK2B, STAT3, and JAK1/3, providing critical evidence for therapeutic target screening. Furthermore, qPCR verification indicated that the expressions of innate immune receptors TLR2, TLR4, TLR7, and TLR10, as well as pro-inflammatory factors IL-1β, IL-16, TNF-α, type I interferon (IFN-α), and nuclear transcription factor NF-κB were significantly upregulated in a time-dependent manner (p < 0.05). In conclusion, this study delineated the dynamic response of ovine mammary tissue to S. aureus infection, systematically elucidated temporal gene expression patterns, and revealed the molecular mechanisms underlying the tissue’s initial defense against inflammatory challenges. Full article

Background/Objectives: β-Carotene oxygenase-2 (BCO2) is a mitochondrial carotenoid-cleaving enzyme expressed in multiple tissues, including the lungs. While BCO2 regulates carotenoid handling, its role in shaping pulmonary immune architecture and antiviral responses is unknown. We hypothesized that BCO2 deficiency reprograms epithelial–innate circuits and alters antiviral outcomes. Methods: BCO2-knockout (KO) and C57BL/6J wild-type (WT) mice underwent lung single-cell RNA sequencing (scRNA-seq), immunoblotting, and intranasal SARS-CoV-2 challenge to assess cell-type heterogeneity, pathway programs (by gene set variation analysis, GSVA), and antiviral responses. Results: scRNA-seq resolved 14 major lung cell populations with cell-type-specific pathway shifts. Compared with WT, BCO2 KO lungs showed increased conventional dendritic cells and natural killer (NK) cells, with reductions in macrophages, B cells, and endothelial cells. In KO alveolar type II cells, GSVA indicated a stress-adapted metabolic program. Ciliated epithelium exhibited vitamin-K-responsive and axoneme-remodeling signatures with attenuated glucocorticoid and very-low-density lipoprotein remodeling. Innate lymphoid type 2 cells favored fatty acid oxidation and chromatin dynamics with reduced mitochondrial activity. NK cells were biased toward constitutive chemokine/cytokine secretion and counter-inflammatory signaling. Immunoblotting confirmed the elevated level of interferon regulatory factor-3 protein in BCO2-KO lungs. Functionally, BCO2-KO mice had improved outcomes after intranasal SARS-CoV-2 exposure. Conclusions: Loss of BCO2 reconfigures the pulmonary immune landscape and enhances antiviral responsiveness in mice. These findings identify BCO2 as a nutrient-linked enzyme with immunomodulatory impact and highlight cell-state changes as candidate mechanisms for improved antiviral tolerance. Full article

Bats are natural reservoirs for diverse viruses, yet they rarely develop disease, suggesting unique antiviral adaptations. In this study, we performed a comprehensive genome-wide analysis in the common vampire bat (Desmodus rotundus), integrating comparative genomics, functional annotation, microRNA (miRNA) discovery, target prediction, and network-based analyses. Comparative genomic analysis revealed that Phyllostomus discolor exhibits the highest protein homology (97.4%) with D. rotundus. Alignment of interferon regulatory factors (IRFs) indicated strong conservation of IRF1, IRF5, and IRF8, while IRF4 and IRF7 showed divergence, reflecting bat-specific modulation of interferon signaling. Functional annotation of previously uncharacterized proteins identified immune-related elements, including toll-like receptor 4, syncytin-1, and endogenous retroviral sequences, highlighting the integration of viral components into host immunity. We further identified 19 novel miRNAs in D. rotundus, with high-confidence target genes such as SOD2, TRIM28, and FGFR1 involved in antiviral defense, apoptosis regulation, and oxidative stress response. Functional enrichment analyses revealed processes associated with wound healing, apoptosis suppression, infection response, and longevity. Network entropy analysis highlighted central regulatory hubs, including MYC, BCL2, and KIF1B, influencing cell cycle, survival, and immune balance. Collectively, these results demonstrate that D. rotundus employs an integrated regulatory network combining conserved immune factors, lineage-specific gene divergence, and miRNA-mediated fine-tuning to achieve viral tolerance without pathology. This study expands our understanding of bat antiviral biology and provides candidate molecular targets for future functional and translational research. Full article

Atherosclerosis is characterized by atherosclerotic plaque formation in large and medium vessels, mediated by endothelial cell (EC) dysfunction, altered contractility of Vascular Smooth Muscle Cells (VSMCs) and recruitment of blood leukocytes to the injured vascular endothelium. These include macrophages (MØ), T lymphocytes, and dendritic cells, which drive the production of many inflammatory mediators and the process of chronic inflammation. Also, de-differentiation or phenotypic switching of VSMCs contributes to vascular remodeling and the pathogenesis of atherosclerosis. Likewise, MØ plasticity and the presence of different phenotypes have a major effect on atherosclerotic plaque formation. The multi-functional transcriptional regulator and pluripotency factor Krüppel-like factor 4 (KLF4) acts as a gatekeeper of VSMC phenotypic switching and MØ polarization during vascular inflammation and atherosclerosis. Similarly, pro-inflammatory pathways activated by Toll-like receptor (TLR)4 and Interferon gamma (IFNγ) emerge as key components of VSMC and MØ plasticity, tightly regulated by Signal Transducer and Activator of Transcription (STAT)s, Interferon Regulatory Factor (IRF)s, and Nuclear factor-κB (NF-κB). Recent discoveries predict a collaborative role of these transcription factors in different transcriptional mechanisms connected to inflammation and atherosclerosis. This review provides novel insight into the transcriptional regulatory interplay between KLF4, STATs, IRFs, and NF-κB in VSMC phenotypic switching and MØ polarization during atherogenesis. Detailed understanding of these transcriptional networks will enable us to develop novel diagnostic and therapeutic strategies to combat vascular proliferative diseases, including atherosclerosis. Full article

HSV-2 is the main pathogen causing genital herpes, and its infection increases the infection and transmission of HIV-1. Currently, there are no vaccines to prevent HSV-2 infection or treatment that can fully cure it. Mining key host factors that regulate HSV-2 replication and elucidating their specific regulatory mechanisms are crucial for understanding virus–host interactions and discovering new antiviral targets. In the current study, we identified DDX43 as a cellular factor involved in the suppression of HSV-2 replication through comparative transcriptomic analyses of HSV-2-infected epithelial cells, followed by experimental validation. Comprehensive transcriptomic profiling revealed distinct host cellular gene expression patterns in HeLa and ARPE-19 cell lines post HSV-2 infection. Subsequent orthogonal partial least-squares discriminant analysis (OPLS-DA) pinpointed DDX43 as one of the principal mediators distinguishing the host response between HSV-2-infected HeLa and ARPE-19 cells. Furthermore, overexpression of DDX43 inhibited HSV-2 replication, whereas knockdown of endogenous DDX43 enhanced HSV-2 replication. Additional experiments revealed that human DDX43 inhibits HSV-2 replication in an interferon-independent manner. This study demonstrates that DDX43 serves as a host regulator against HSV-2 infection, underscoring the power of comparative transcriptomics in identifying novel host proteins that modulate viral replications. Full article

Interferon Regulatory Factor 5 plays an important role in the regulation of innate immune responses by amplifying the Nuclear Factor κB response, which is critical in gout inflammation. Furthermore, the rs4728141 polymorphism C allele was associated with both increased IRF5 expression and susceptibility to gout. We examine the association between rs4728141 and cytokine production in response to various Toll-Like Receptor ligands and describe the transcriptomic and proteomic changes observed in patients with gout and controls in relation to this polymorphism. We examine the transcriptome of freshly isolated peripheral blood mononuclear cells (PBMCs) from 93 normouricemic donors and 63 gout patients as well as serum inflammatory proteome in 197 control and 195 gout samples. Stimulation experiments of freshly isolated human PBMCs were performed over 24 h, followed by RNA-sequencing in gout patients and cytokine production measurement by ELISA in normouricemic donors and gout patients. The rs4728141 C allele was associated with increased IL-1β expression in unstimulated PBMCs of controls, but not in gout. No association between the polymorphism and serum inflammatory proteome was found. As expected, an increased IRF5 expression was observed in stimulated PBMCs of rs4728141 C allele carriers in response to several stimulations. Interestingly, IL-1β production was specifically enhanced in association to the rs4728141 C allele when cells were stimulated with palmitate with or without monosodium urate crystals. This pattern of cytokine production shows a functional impact of rs4728141 in gout through altered IL-1β production. Full article

Skin cancer is the most common cancer worldwide. The incidence of skin cancer has been increasing worldwide. Nearly 75% of all skin cancers are basal cell carcinomas (BCC), cutaneous squamous cell carcinoma (cSCC) represents approximately 20%, and those remaining are melanomas (4%) or other rare tumors (1%). Given the high cure rates and the ability to histologically confirm tumor clearance, surgical therapy is the gold standard for the treatment of skin cancer. Conventional surgery is the most employed technique for the removal of non-melanoma skin cancer (NMSCs). Mohs Micrographic Surgery (MMS) is the most precise surgical method for the treatment of non-melanoma skin cancer, allowing for 100% margin evaluation, being the gold-standard method for surgical treatment of non-melanoma skin cancer. Whenever it is possible to obtain wide margins (4 to 6 mm), cure rates vary from 70% to 99%. Imiquimod, a synthetic imidazoquinolinone amine, is a topical immune response modifier approved by the U.S. Food and Drug Administration (FDA) for the treatment of external anogenital warts, actinic keratosis (AK), and superficial basal cell carcinoma (sBCC). The efficacy of imiquimod is primarily attributed to its ability to modulate both innate and adaptive immune responses, as well as its direct effects on cancer cells. Imiquimod exerts its immunomodulatory effects by activating Toll-like receptors 7 and 8 (TLR7/8) on various immune cells, including dendritic cells, macrophages, and natural killer (NK) cells. Upon binding to these receptors, imiquimod triggers the MyD88-dependent signaling pathway, leading to the activation of nuclear factor kappa B (NF-κB) and interferon regulatory factors (IRFs). This cascade leads to the production of pro-inflammatory cytokines, including interferon-alpha (IFN-α), tumor necrosis factor-alpha (TNF-α), interleukin-12 (IL-12), and interleukin-6 (IL-6). These cytokines enhance local inflammation, recruit additional immune cells to the tumor site, and stimulate antigen presentation, thereby promoting an anti-tumor immune response. Radiation therapy (RTh) may be employed as a primary treatment to BCC. It may also be employed as an adjuvant treatment to surgery for SCC and aggressive subtypes of BCC. RTh triggers both direct and indirect DNA damage on cancer cells and generates reactive oxygen species (ROS) within cells. ROS trigger oxidative damage to DNA, proteins, and lipids, exacerbating the cellular stress and contributing to tumor cell death. Recently, immunotherapy emerged as a revolutionary treatment for all stages of SCC. Cemiplimab is a human programmed cell death 1 (PD-1)-blocking antibody that triggers a response to over 50% of patients with locally advanced and metastatic SCC. A randomized clinical trial (RCT) published in 2022 revealed that cemiplimab was highly effective in the neoadjuvant treatment of large SCCs. The drug promoted a significant tumor size decrease, enabling organ-sparing operations and a much better cosmetic effect. A few months ago, a RCT of cemiplimab on adjuvant therapy for locally aggressive SCC was published. Interestingly, cemiplimab was administered to patients with local or regional cutaneous squamous cell carcinoma after surgical resection and postoperative radiotherapy, at high risk for recurrence owing to nodal features, revealed that cemiplimab led to much lower risks both of locoregional recurrence and distant recurrence. Full article

Background: Inflammatory bowel disease (IBD), including Crohn’s disease (CD) and ulcerative colitis (UC), is characterized by chronic inflammation affecting the gastrointestinal tract and extraintestinal organs. The etiology of IBD is multifactorial, involving genetic, immunological, and environmental factors. Over 200 genetic loci have been associated with the disease, indicating a significant genetic predisposition. Despite advances in understanding its genetic basis, clinical management remains challenging due to heterogeneity in disease presentation and variable treatment responses. Current therapies, such as 5-aminosalicylates and biologics, are not universally effective, underscoring the need for reliable biomarkers to predict therapeutic responses. Objective: This study investigates the potential role of interferon regulatory factor 5 (IRF5) in the pathogenesis of IBD, with a particular focus on UC. Methods: We conducted a systematic analysis of colon biopsies from 30 adult patients diagnosed with UC and from 8 non-IBD controls. Immunostaining was performed to assess IRF5 expression in colonic tissues using the primary IRF5 antibody (1:300, Abcam, ab181553). Statistical analyses evaluated the correlation between IRF5-positive cell counts, disease activity, and inflammatory markers such as calprotectin. Results: Our analysis revealed a significant increase in IRF5-positive macrophage-like cells in the inflamed mucosa of IBD patients compared to healthy controls. The number of IRF5-positive cells showed a positive correlation with disease activity and calprotectin levels, indicating that higher IRF5 expression is associated with increased inflammation. Conclusions: This study demonstrates a significant correlation between IRF5 expression and disease activity in UC, suggesting that IRF5 may play a crucial role in the inflammatory processes of the disease. The findings propose IRF5 as a novel biomarker for therapeutic intervention in IBD. Further research is needed to clarify the mechanisms by which IRF5 contributes to IBD pathogenesis and to explore the therapeutic potential of targeting this pathway in clinical settings. Full article

Interferon regulatory factor 5 (IRF5) plays a pivotal role in innate immune responses and macrophage polarization. Although its role in obesity-associated inflammation has been described, sex-specific differences in adipose IRF5 expression and its association with immune and metabolic markers remain poorly defined. To evaluate sex-specific associations between adipose tissue (AT) IRF5 expression and key inflammatory and metabolic markers in overweight and obese individuals. Subcutaneous AT samples from overweight/obese male and female subjects were analyzed for IRF5 expression using quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Correlation and multiple linear regression analyses were performed to identify its associations with inflammatory gene expression and metabolic parameters including insulin, glucose, HOMA-IR, and adipokines. RF5 gene and protein levels were significantly elevated in the AT of overweight/obese females compared to males (p < 0.0001), with expression increasing progressively with BMI in females but not in males. Despite these sex-dependent expression levels, IRF5 demonstrated consistent, sex-independent positive correlations with several core immune and inflammatory markers, including CCR5, CD11c, CD16, CD163, FOXP3, RUNX1, and MyD88. However, distinct sex-specific patterns emerged: in males, IRF5 correlated positively with classical pro-inflammatory markers such as IL-2, IL-6, IL-8, TNF-α, and IRAK1; whereas in females, IRF5 was associated with a broader array of immune markers, including chemokines (CCL7, CXCL11), pattern recognition receptors (TLR2, TLR8, TLR9), and macrophage markers (CD68, CD86), along with anti-inflammatory mediators such as IL-10 and IRF4. Notably, IRF5 expression in overweight/obese males, but not females, was significantly associated with metabolic dysfunction, showing positive correlations with fasting blood glucose, HbA1c, insulin, and homeostatic model assessment for insulin resistance (HOMA-IR) levels. Multiple regression analyses revealed sex-specific predictors of IRF5 expression, with metabolic (HOMA-IR) and inflammatory (IRAK1, MyD88) markers emerging in males, while immune-related genes (RUNX1, CD68, CCL7, MyD88) predominated in females. These findings underscore a sex-divergent role of IRF5 in AT, with implications for differential regulation of immune-metabolic pathways in obesity and its complications. Full article

Lidocaine exhibited anti-inflammatory and immunomodulatory properties. This study aimed to investigate the anti-inflammatory effects of the lidocaine-derived analogs, EI137 and EI341, in a Staphylococcal enterotoxin B (SEB)-induced chronic rhinosinusitis (CRS). A CRS model was established using BALB/c mice via intranasal instillation of SEB. EI137 and EI341 were administered intranasally at 0.5 μg/g and 5 μg/g, respectively. Nasal symptoms and interleukin (IL)-4, IL-10, interferon (IFN)-γ, and tumor necrosis factor (TNF)-α levels in the nasal lavage fluid (NLF) were assessed. The reverse-transcription polymerase chain reaction was used to identify IFN-γ, IL-4, IL-10, and their transcription factors in the sinonasal mucosa. Histological changes were performed to assess inflammatory cell infiltration, epithelial thickness, and mucus-producing cells. SEB induced significant increases in IL-4, IL-10, and TNF-α levels in NLF and sinonasal mucosa, along with marked inflammatory cell infiltration. Intranasal EI137 and EI341 administration significantly reduced Th2 cytokine and its transcription factor, inflammatory cell infiltration, and mucus-producing cell numbers in the sinonasal mucosa. Further, EI137 suppressed Th1 cytokines, whereas EI341 enhanced Th1 responses. Both compounds promoted regulatory T cell responses, as evidenced by increased IL-10 and Foxp3 mRNA expression. EI137 and EI341 demonstrated potent local anti-inflammatory effects in a SEB-induced CRS model by modulating Th2 and Treg responses. EI137 suppressed Th1 inflammation, whereas EI341 enhanced it. These results indicate that EI137 and EI341 are promising topical agents for Th2-dominant inflammatory diseases, with distinct effects on Th1 immune responses. Full article

Nuclear factors of activated T cells (NFATs) are pivotal regulatory factors of immune responses, primarily by modulating T cell activity and regulating inflammatory cytokine gene transcription. The grass carp reovirus (GCRV) triggers a serious hemorrhagic condition, posing a significant threat to sustainable grass carp (Ctenopharyngodon idella) aquaculture. However, the precise function of NFAT in the host’s defense against GCRV infection is mostly undefined. This study comprehensively identified and characterized the NFAT genetic family in grass carp, cloned grass carp NFAT1 (CiNFAT1), and investigated its expression and function during GCRV infection. Eight NFAT genes encoding seventeen isoforms have been detected within the grass carp’s genomic sequence, distributed across six different chromosomes. Comparative analysis revealed homology with zebrafish NFATs. CiNFAT1 possesses a 2697 bp open reading frame, encoding 898 amino acids, and contains conserved Rel homology domain (RHD) and NFAT-homology (IPT) domains. Quantitative PCR (qPCR) revealed ubiquitous CiNFAT1 expression in healthy grass carp tissues, with the highest expression in gills and skin and the lowest in liver. Following GCRV challenge in vivo, CiNFAT1 expression in immune tissues (liver, spleen, kidney, gill, intestine) showed dynamic changes over time. In vitro experiments in CIK cells demonstrated that CiNFAT1 expression peaked at 12 h post-GCRV infection. Further functional studies revealed that overexpression of CiNFAT1 significantly reduced GCRV replication at 36 h post-infection. This reduction was accompanied by elevated expression of type I interferon (IFN-I) and interferon regulatory factor 7 (IRF7) at 24 and 36 h, respectively, as well as modulated IL-2, IL-8, and IL-10. Conversely, RNA interference-mediated knockdown of CiNFAT1 enhanced GCRV VP5 and VP7 mRNA levels and suppressed IL-2 and IL-8 expression. These results suggest that CiNFAT1 contributes to anti-GCRV immunity by promoting antiviral and inflammatory cytokine responses, thereby inhibiting viral replication. This study provides a foundational understanding of the NFAT genetic family in grass carp and highlights an important role of CiNFAT1 in mediating the body’s inherent defense mechanism against GCRV infection, offering insights for disease control strategies in aquaculture. Full article

Měnglà virus (MLAV) is a member of the genus Dianlovirus in the family Filoviridae, which also includes Ebola virus (EBOV) and Marburg virus (MARV). Whether MLAV poses a threat to human health is uncertain. However, the MLAV VP35 and VP40 proteins can impair IFNα/β gene expression and block IFNα/β-induced Jak-STAT signaling, respectively, suggesting the capacity to counteract human innate immune defenses. In this study, MLAV VP40 is demonstrated to impair the Sendai virus (SeV)-induced activation of the IFNβ promoter. Inhibition is independent of the MLAV VP40 PPPY late-domain motif that interacts with host proteins possessing WW-domains to promote viral budding. Similar IFNβ promoter inhibition was not detected for EBOV or MARV VP40. MLAV VP40 exhibited lesser capacity to inhibit TNFα activation of an NF-κB reporter gene. MLAV VP40 impaired IFNβ promoter activation by an over-expressed, constitutively active form of RIG-I and by the over-expressed IRF3 kinases TBK1 and IKKε. However, MLAV VP40 did not inhibit IFNβ promoter activation by constitutively active IRF3 5D. Consistent with these findings, MLAV VP40 inhibited SeV-induced IRF3 phosphorylation. Although IRF3 phosphorylation occurs in the cytoplasm, MLAV VP40 exhibits substantial nuclear localization, accumulating in foci in HeLa cell nuclei. In contrast, the VP40 of EBOV and MARV exhibited lower degrees of nuclear localization and did not accumulate in foci. MLAV VP40 interacts with importin alpha-1 (IMPα1), suggesting entry via the IMPα/IMPβ nuclear import pathway. Cumulatively, these data identify novel features that distinguish MLAV VP40 from its homologues in EBOV and MARV. Full article

Fecal microbiota transplantation (FMT) promotes growth performance and intestinal development in yellow-feathered broilers, but whether the virome and metabolites contribute to its growth-promoting effect remains unclear. This study removed the microbiota from FMT filtrate using a 0.45 μm filter membrane, retaining the virome and metabolites to perform fecal virome transplantation (FVT), aiming to investigate its regulatory role in broiler growth. Healthy yellow-feathered broilers with high body weights (top 10% of the population) were used as FVT donors. Ninety-six 8-day-old healthy male yellow-feathered broilers (95.67 ± 3.31 g) served as FVT recipients. Recipient chickens were randomly assigned to a control group and an FVT group. The control group was gavaged with 0.5 mL of normal saline daily, while the FVT group was gavaged with 0.5 mL of FVT solution daily. Growth performance, immune and antioxidant capacity, intestinal development and related gene expression, and microbial diversity were measured. The results showed that FVT improved the feed utilization rate of broilers (the feed conversion ratio decreased by 3%; p < 0.05), significantly increased jejunal length (21%), villus height (69%), and crypt depth (84%) (p < 0.05), and regulated the jejunal barrier: insulin-like growth factor-1 (IGF-1) (2.5 times) and Mucin 2 (MUC2) (63 times) were significantly upregulated (p < 0.05). FVT increased the abundance of beneficial bacteria Lactobacillales. However, negative effects were also observed: Immunoglobulin A (IgA), Immunoglobulin G (IgG), Immunoglobulin M (IgM), Interleukin-1 beta (IL-1β), Interleukin-6 (IL-6), Tumor Necrosis Factor-alpha (TNF-α), and Interferon-gamma (IFN-γ) in broilers were significantly upregulated (p < 0.05), indicating immune system overactivation. Duodenal barrier-related genes Mucin 2 (MUC2), Occludin (OCLN), Claudin (CLDN1), and metabolism-related genes solute carrier family 5 member 1 (SLC5A1) and solute carrier family 7 member 9 (SLC7A9) were significantly downregulated (p < 0.05). The results of this trial demonstrate that, besides the microbiota, the gut virome and metabolites are also functional components contributing to the growth-promoting effect of FMT. The differential responses in the duodenum and jejunum reveal spatial heterogeneity and dual effects of FVT on the intestine. The negative effects limit the application of FMT/FVT. Identifying the primary functional components of FMT/FVT to develop safe and targeted microbial preparations is one potential solution. Full article