Lung transcriptional unresponsiveness and loss of early influenza virus control in infected neonates is prevented by intranasal Lactobacillus rhamnosus GG

Maternal probiotic exposure enhances CD8 T cell protective neonatal immunity and modulates offspring metabolome to control influenza virus infection

Maternal gut microbiota composition contributes to the status of the neonatal immune system and could influence the early life higher susceptibility to viral respiratory infections. Using a novel protocol of murine maternal probiotic supplementation, we report that perinatal exposure to Lacticaseibacillus rhamnosus (L.rh) or Bifidobacterium animalis subsp. lactis (B.lac) increases the influenza A/PR8 virus (IAV) clearance in neonates. Following either supplementation, type 1 conventional dendritic cells (cDC1) were amplified in the lymph nodes leading to an enhanced IAV antigen-experienced IFN-γ producing effector CD8 T cells in neonates and IAV-specific resident memory CD8 T cells in adulthood. This was compatible with a higher protection of the offspring upon a secondary infection. Interestingly, only mice born to L.rh supplemented mothers further displayed an increased activation of IFN-γ producing virtual memory CD8 T cells and a production of IL-10 by CD4 and CD8 T cells that could explain a better control of the lung damages upon infection. In the offspring and the mothers, no disturbance of the gut microbiota was observed but, as analyzed through an untargeted metabolomic approach, both exposures modified neonatal plasma metabolites. Among them, we further demonstrated that genistein and 3-(3-hydroxyphenyl)propionic acid recapitulate viral clearance or cDC1 activation in neonates exposed to IAV. We conclude that maternal L.rh or B.lac supplementation confers the neonates specific metabolomic modulations with a better CD8 T cell-mediated immune protection against IAV infection.

Antiviral Activity of Marine Bacterium Paraliobacillus zengyii Against Enterovirus 71 In Vitro and In Vivo

Enterovirus 71 (EV71) is the major causative agent of hand, foot, and mouth disease (HFMD), leading to a serious health threat to young children. Probiotics are effective at treating or preventing gastrointestinal infections, especially viral infections. Probiotics against EV71 are mainly traditional lactic acid-producing bacteria, and most of them have been proven to be effective only in vitro. Here, we report that the marine bacterium Paraliobacillus zengyii X-1125 (P. zengyii) has promising anti-EV71 activity. The antiviral effect of P. zengyii against EV71 was assessed in different cell lines, and the viral RNA levels and titers were obviously reduced after treatment with P. zengyii. Furthermore, we established an EV71-infected mouse model to evaluate its antiviral efficacy in vivo. The oral administration of P. zengyii significantly decreased the viral loads in the hindlimb muscles, spleens, and ileums. Further research revealed that P. zengyii enhances the expression of type I interferon (IFN-I) in EV71-infected cells. Similarly, transcriptome analysis indicated that the expression of interferon-stimulated genes (ISGs) in EV71-infected mice significantly increased after P. zengyii treatment. Taken together, the results of this study indicated that P. zengyii markedly reduces EV71 infection by regulating the IFN response both in vivo and in vitro, providing a potential means to work against EV71 infection.

Cathelicidin-related antimicrobial peptide (CRAMP) is toxic during neonatal murine influenza virus infection

Respiratory viral infections are a major contributor to mortality in children under 5 years of age, and disproportionately affect preterm neonates. Previously, using our established 3-day-old neonatal murine model of influenza virus infection, we demonstrated that treatment of neonatal mice with intranasal Lactobacillus rhamnosus GG (LGG) prior to influenza viral infection improved survival. Transcriptional analysis revealed expression of the mouse cathelicidin-related antimicrobial peptide (CRAMP, encoded by CRAMP) was downregulated in LGG-treated neonates. Mouse CRAMP is a key effector protein secreted by infected epithelial cells and resident and infiltrating immune cells, but the role of CRAMP in neonatal defense to respiratory viruses is unknown. Neonatal mice with a deleted CRAMP gene (CRAMP-/-) were intranasally infected with influenza virus. CRAMP-/- neonates had improved survival over C57BL/6 neonates after influenza viral infection (75% vs. 14%, p < 0.05). Next, immune cell recruitment to the lung of infected neonates was determined. Surprisingly, at 3-days postinfection, there was increased recruitment of neutrophils, inflammatory monocytes, and alveolar macrophages, coupled with increased proinflammatory cytokine and chemokine production in CRAMP-/- compared to C57BL/6 neonates. However, this changed over the first week of infection. C57BL/6 neonatal mice increased CRAMP production significantly, in direct contrast to their adult counterparts. Inflammatory cytokine production increased that indicated CRAMP amplified the innate immune response later in the infection. Furthermore, we identified pulmonary nonimmune cells as an important source of increased CRAMP levels as the infection progressed and CRAMP production drove mortality. These insights emphasize the age-specific role of CRAMP in influenza viral pathogenesis.

Synergy between Lactobacillus murinus and anti-PcrV antibody delivered in the airways to boost protection against Pseudomonas aeruginosa

Therapeutic antibodies (Ab) have revolutionized the management of multiple illnesses including respiratory tract infections (RTIs). However, anti-infectious Ab displayed several limitations including antigen restrictiveness, narrowed therapeutic windows, and limited dose in the vicinity of the target when delivered by parenteral routes. Strategies enhancing further Ab-dependent containment of infection are currently needed. Here we showed that a combination of inhaled anti-infectious Ab and probiotics is an efficient formulation to protect against lung infection. Using a mouse model of Pseudomonas aeruginosa-induced pneumonia, we demonstrated a synergistic effect reducing both bacterial burden and pro-inflammatory response affording protection against primary and secondary infections. This is the first study showing that the local combination in the airways of anti-infective Ab and probiotics subverts suboptimal potency of Ab monotherapy and provides protection against respiratory pathogen.

Lactobacillus rhamnosus GG Regulates Host IFN-I Through the RIG-I Signalling Pathway to Inhibit Herpes Simplex Virus Type 2 Infection

Numerous recent studies have demonstrated that the commensal microbiota plays an important role in host immunity against infections. During the infection process, viruses can exhibit substantial and close interactions with the commensal microbiota. However, the associated mechanism remains largely unknown. Therefore, in this study, we explored the specific mechanisms by which the commensal microbiota modulates host immunity against viral infections. We found that the expression levels of type I interferon (IFN-I) and antiviral priming were significantly downregulated following the depletion of the commensal microbiota due to treatment with broad-spectrum antibiotics (ABX). In addition, we confirmed a unique molecular mechanism underlying the induction of IFN-I mediated by the commensal microbiota. In vivo and in vitro experiments confirmed that Lactobacillus rhamnosus GG (LGG) can suppress herpes simplex virus type 2 (HSV-2) infection by inducing IFN-I expression via the retinoic acid-inducible gene-I (RIG-I) signalling pathway. Therefore, the commensal microbiota-induced production of IFN-I provides a potential therapeutic approach to combat viral infections. Altogether, understanding the complexity and the molecular aspects linking the commensal microbiota to health will help provide the basis for novel therapies already being developed.

Effects of intranasal administration with a symbiotic strain of Bacillus velezensis NSV2 on nasal cavity mucosal barrier in lambs

The nasal mucosa is composed of multiple layers of barrier structures and is the first line of defense against infection by respiratory pathogenic microorganisms. A large number of commensal microorganisms are present in the nasal mucosa that mediate and regulate nasal mucosal barrier function. The objective of this research was to investigate the effects of commensal microorganisms on the nasal mucosal barrier. The results revealed that the strain of Bacillus velezensis (B. velezensis) NSV2 from the nasal cavity has good probiotic abilities to resist Pasteurella multocida, Staphylococcus aureus, Escherichia coli and Salmonella typhimurium. Lambs were subsequently administered intranasally with B. velezensis NSV2 at 3, 12, 21, and 26 days old, respectively. For the microbial barrier, although B. velezensis NSV2 reduces the diversity of nasal microbiota, it significantly increased the relative abundance of beneficial bacteria in the nasal cavity, and reduced the abundance of potential pathogenic bacteria. For the mucus barrier, the number of goblet cells in the nasal mucosa significantly increased after B. velezensis NSV2 treatment. For the immune barrier, B. velezensis NSV2 also significantly increased the number of IgA+ B cells, CD3+ T cells and dendritic cells in the nasal mucosa, as well as the mRNA expression of interleukin (IL) 6, IL11, CCL2, and CCL20 (P < 0.05). The protein level of CCL20 also significantly raised in nasal washings (P < 0.05). Moreover, the heat-inactivated and culture products of B. velezensis NSV2 also drastically induced the expression of CCL20 in nasal mucosa explants (P < 0.05), but lower than that of the live bacteria. This study demonstrated that a symbiotic strain of B. velezensis NSV2 could improve the nasal mucosal barrier, and emphasized the important role of nasal symbiotic microbiota.

Engineered probiotic Escherichia coli elicits immediate and long-term protection against influenza A virus in mice

Influenza virus infection remains a major global health problem and requires a universal vaccine with broad protection against different subtypes as well as a rapid-response vaccine to provide immediate protection in the event of an epidemic outbreak. Here, we show that intranasal administration of probiotic Escherichia coli Nissle 1917 activates innate immunity in the respiratory tract and provides immediate protection against influenza virus infection within 1 day. Based on this vehicle, a recombinant strain is engineered to express and secret five tandem repeats of the extracellular domain of matrix protein 2 from different influenza virus subtypes. Intranasal vaccination with this strain induces durable humoral and mucosal responses in the respiratory tract, and provides broad protection against the lethal challenge of divergent influenza viruses in female BALB/c mice. Our findings highlight a promising delivery platform for developing mucosal vaccines that provide immediate and sustained protection against respiratory pathogens.

The Role of Gut Microbiome Supplementation in COVID-19 Management

COVID-19, which is caused by the RNA virus, SARS-CoV-2, mainly affects the respiratory system and has a varied clinical presentation. However, several studies have shown that COVID-19 can also affect the gastrointestinal (GI) system. Patients can experience various GI symptoms, such as vomiting and diarrhea, and the virus has been detected in the stool samples of patients hospitalized with COVID-19. There have also been rare reports of COVID-19 presenting with isolated GI symptoms and lack of respiratory symptoms, and the virus has also been detected for prolonged periods in the fecal samples of COVID-19 patients. Major alterations in the gut microbiome in the form of depletion of beneficial organisms and an abundance of pathogenic organisms have been reported in the fecal samples of hospitalized COVID-19 patients. Although the US FDA has approved several drugs to manage COVID-19, their efficacy remains modest. So, there is a constant ongoing effort to investigate novel treatment options for COVID-19. Health supplements like probiotics, prebiotics, postbiotics, and synbiotics have been popularly known for their various health benefits. In this review, we have summarized the current literature, which shows the potential benefit of these health supplements to mitigate and/or prevent the clinical presentation of COVID-19.

Interferons-Implications in the Immune Response to Respiratory Viruses

Interferons (IFN) are an assemblage of signaling proteins made and released by various host cells in response to stimuli, including viruses. Respiratory syncytial virus (RSV), influenza virus, and SARS-CoV-2 are major causes of respiratory disease that induce or antagonize IFN responses depending on various factors. In this review, the role and function of type I, II, and III IFN responses to respiratory virus infections are considered. In addition, the role of the viral proteins in modifying anti-viral immunity is noted, as are the specific IFN responses that underly the correlates of immunity and protection from disease.

COVID-19 induced ARDS: immunopathology and therapeutics

The coronavirus disease-2019 (COVID-19) pandemic is a significant threat in the modern era. Clinical studies show that the most common symptom of severe COVID-19 is viral pneumonia-induced acute respiratory distress syndrome (ARDS). The underlying mechanisms by which severe respiratory disease syndrome-coronavirus-2 (SARS-CoV-2) results in ARDS and how certain host factors confer an increased risk of developing severe disease remain unknown. Therefore, identifying the distinctive features of this severe and fatal disease and the therapeutic approaches to COVID-19-induced ARDS remains an immediate need to serve as a basis for best practice models of standardized ARDS treatment. This review article aims to comprehensively discuss the immunopathology of ARDS and provides an overview of the precise role of both the innate and adaptive immune system, with emphasis on the current treatment strategies being tested in the COVID-19-induced ARDS patients. This knowledge will supposedly help in revealing further mechanistic insights into understanding COVID-19-induced ARDS.

Functional Foods: A Promising Strategy for Restoring Gut Microbiota Diversity Impacted by SARS-CoV-2 Variants

Natural herbs and functional foods contain bioactive molecules capable of augmenting the immune system and mediating anti-viral functions. Functional foods, such as prebiotics, probiotics, and dietary fibers, have been shown to have positive effects on gut microbiota diversity and immune function. The use of functional foods has been linked to enhanced immunity, regeneration, improved cognitive function, maintenance of gut microbiota, and significant improvement in overall health. The gut microbiota plays a critical role in maintaining overall health and immune function, and disruptions to its balance have been linked to various health problems. SARS-CoV-2 infection has been shown to affect gut microbiota diversity, and the emergence of variants poses new challenges to combat the virus. SARS-CoV-2 recognizes and infects human cells through ACE2 receptors prevalent in lung and gut epithelial cells. Humans are prone to SARS-CoV-2 infection because their respiratory and gastrointestinal tracts are rich in microbial diversity and contain high levels of ACE2 and TMPRSS2. This review article explores the potential use of functional foods in mitigating the impact of SARS-CoV-2 variants on gut microbiota diversity, and the potential use of functional foods as a strategy to combat these effects.

Nutrients, herbal bioactive derivatives and commensal microbiota as tools to lower the risk of SARS-CoV-2 infection

The SARS-CoV-2 outbreak has infected a vast population across the world, causing more than 664 million cases and 6.7 million deaths by January 2023. Vaccination has been effective in reducing the most critical aftermath of this infection, but some issues are still present regarding re-infection prevention, effectiveness against variants, vaccine hesitancy and worldwide accessibility. Moreover, although several old and new antiviral drugs have been tested, we still lack robust and specific treatment modalities. It appears of utmost importance, facing this continuously growing pandemic, to focus on alternative practices grounded on firm scientific bases. In this article, we aim to outline a rigorous scientific background and propose complementary nutritional tools useful toward containment, and ultimately control, of SARS-CoV-2 infection. In particular, we review the mechanisms of viral entry and discuss the role of polyunsaturated fatty acids derived from α-linolenic acid and other nutrients in preventing the interaction of SARS-CoV-2 with its entry gateways. In a similar way, we analyze in detail the role of herbal-derived pharmacological compounds and specific microbial strains or microbial-derived polypeptides in the prevention of SARS-CoV-2 entry. In addition, we highlight the role of probiotics, nutrients and herbal-derived compounds in stimulating the immunity response.

Immunological consequences of microbiome-based therapeutics

The complex network of microscopic organisms living on and within humans, collectively referred to as the microbiome, produce wide array of biologically active molecules that shape our health. Disruption of the microbiome is associated with susceptibility to a range of diseases such as cancer, diabetes, allergy, obesity, and infection. A new series of next-generation microbiome-based therapies are being developed to treat these diseases by transplanting bacteria or bacterial-derived byproducts into a diseased individual to reset the recipient's microbiome and restore health. Microbiome transplantation therapy is still in its early stages of being a routine treatment option and, with a few notable exceptions, has had limited success in clinical trials. In this review, we highlight the successes and challenges of implementing these therapies to treat disease with a focus on interactions between the immune system and microbiome-based therapeutics. The immune activation status of the microbiome transplant recipient prior to transplantation has an important role in supporting bacterial engraftment. Following engraftment, microbiome transplant derived signals can modulate immune function to ameliorate disease. As novel microbiome-based therapeutics are developed, consideration of how the transplants will interact with the immune system will be a key factor in determining whether the microbiome-based transplant elicits its intended therapeutic effect.

Early life gut microbiota: Consequences for health and opportunities for prevention

The gut microbiota influences many aspects of the host, including immune system maturation, nutrient absorption and metabolism, and protection from pathogens. Increasing evidences from cohort and animal studies indicate that changes in the gut microbiota early in life increases the risk of developing specific diseases early and later in life. Therefore, it is becoming increasingly important to identify specific disease prevention or therapeutic solutions targeting the gut microbiota, especially during infancy, which is the window of the human gut microbiota establishment process. In this review, we provide an overview of current knowledge concerning the relationship between disturbances in the gut microbiota early in life and health consequences later in life (e.g., necrotizing enterocolitis, celiac disease, asthma, allergies, autism spectrum disorders, overweight/obesity, diabetes and growth retardation), with a focus on changes in the gut microbiota prior to disease onset. In addition, we summarize and discuss potential microbiota-based interventions early in life (e.g., diet adjustments, probiotics, prebiotics, fecal microbiota transplantation, environmental changes) to promote health or prevent the development of specific diseases. This knowledge should aid the understanding of early life microbiology and inform the development of prediction and prevention measures for short- and long-term health disorders based on the gut microbiota.

Development of a live biotherapeutic throat spray with lactobacilli targeting respiratory viral infections

Respiratory viruses such as influenza viruses, respiratory syncytial virus (RSV), and coronaviruses initiate infection at the mucosal surfaces of the upper respiratory tract (URT), where the resident respiratory microbiome has an important gatekeeper function. In contrast to gut-targeting administration of beneficial bacteria against respiratory viral disease, topical URT administration of probiotics is currently underexplored, especially for the prevention and/or treatment of viral infections. Here, we report the formulation of a throat spray with live lactobacilli exhibiting several in vitro mechanisms of action against respiratory viral infections, including induction of interferon regulatory pathways and direct inhibition of respiratory viruses. Rational selection of Lactobacillaceae strains was based on previously documented beneficial properties, up-scaling and industrial production characteristics, clinical safety parameters, and potential antiviral and immunostimulatory efficacy in the URT demonstrated in this study. Using a three-step selection strategy, three strains were selected and further tested in vitro antiviral assays and in formulations: Lacticaseibacillus casei AMBR2 as a promising endogenous candidate URT probiotic with previously reported barrier-enhancing and anti-pathogenic properties and the two well-studied model strains Lacticaseibacillus rhamnosus GG and Lactiplantibacillus plantarum WCFS1 that display immunomodulatory capacities. The three strains and their combination significantly reduced the cytopathogenic effects of RSV, influenza A/H1N1 and B viruses, and HCoV-229E coronavirus in co-culture models with bacteria, virus, and host cells. Subsequently, these strains were formulated in a throat spray and human monocytes were employed to confirm the formulation process did not reduce the interferon regulatory pathway-inducing capacity. Administration of the throat spray in healthy volunteers revealed that the lactobacilli were capable of temporary colonization of the throat in a metabolically active form. Thus, the developed spray with live lactobacilli will be further explored in the clinic as a potential broad-acting live biotherapeutic strategy against respiratory viral diseases.

The impact of infection with COVID-19 on the respiratory microbiome: A narrative review

Coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2, has affected millions of individuals with various implications. Consistent with the crucial role of the microbiome in determining health and disease in humans, various studies have investigated the gut and respiratory microbiome effect on the COVID-19. Microbiota dysbiosis might support the entry, replication, and establishment of SARS-CoV-2 infection by modulating various mechanisms. One of the main mechanisms that the modulation of respiratory microbiota composition during the COVID-19 infection affects the magnitude of the disease is changes in innate and acquired immune responses, including inflammatory markers and cytokines and B- and T-cells. The diversity of respiratory microbiota in COVID-19 patients is controversial; some studies reported low microbial diversity, while others found high diversity, suggesting the role of respiratory microbiota in this disease. Modulating microbiota diversity and profile by supplementations and nutrients can be applied prophylactic and therapeutic in combating COVID-19. Here, we discussed the lung microbiome dysbiosis during various lung diseases and its interaction with immune cells, focusing on COVID-19.

Gut microbiome and human health: Exploring how the probiotic genus Lactobacillus modulate immune responses

The highest density of microbes resides in human gastrointestinal tract, known as “Gut microbiome”. Of note, the members of the genus Lactobacillus that belong to phyla Firmicutes are the most important probiotic bacteria of the gut microbiome. These gut-residing Lactobacillus species not only communicate with each other but also with the gut epithelial lining to balance the gut barrier integrity, mucosal barrier defence and ameliorate the host immune responses. The human body suffers from several inflammatory diseases affecting the gut, lungs, heart, bone or neural tissues. Mounting evidence supports the significant role of Lactobacillus spp. and their components (such as metabolites, peptidoglycans, and/or surface proteins) in modulatingimmune responses, primarily through exchange of immunological signals between gastrointestinal tract and distant organs. This bidirectional crosstalk which is mediated by Lactobacillus spp. promotes anti-inflammatory response, thereby supporting the improvement of symptoms pertaining to asthma, chronic obstructive pulmonary disease (COPD), neuroinflammatory diseases (such as multiple sclerosis, alzheimer’s disease, parkinson’s disease), cardiovascular diseases, inflammatory bowel disease (IBD) and chronic infections in patients. The metabolic disorders, obesity and diabetes are characterized by a low-grade inflammation. Genus Lactobacillus alleviates metabolic disorders by regulating the oxidative stress response and inflammatory pathways. Osteoporosis is also associated with bone inflammation and resorption. The Lactobacillus spp. and their metabolites act as powerful immune cell controllers and exhibit a regulatory role in bone resorption and formation, supporting bone health. Thus, this review demonstrated the mechanisms and summarized the evidence of the benefit of Lactobacillus spp. in alleviating inflammatory diseases pertaining to different organs from animal and clinical trials. The present narrative review explores in detail the complex interactions between the gut-dwelling Lactobacillus spp. and the immune components in distant organs to promote host’s health.

Probiotics ameliorates pulmonary inflammation via modulating gut microbiota and rectifying Th17/Treg imbalance in a rat model of PM2.5 induced lung injury

The imbalance of intestinal microbiota and inflammatory response is crucial in the development of lung injury induced by PM2.5. In recent years, probiotics have attracted great attention for their health benefits in inflammatory diseases and regulating intestinal balance, but their intricate mechanisms need further experiments to elucidate. In our research, a rat lung damage model induced by PM2.5 exposure in real environment was established to explore the protective properties of probiotics on PM2.5 exposure injury and its related mechanism. The results indicated that compared with the AF control group, rats in the PM2.5 group gained weight slowly, ate less and had yellow hair. The results of pathological and immunohistochemical examinations showed that the inflammatory infiltration of lung tissue was alleviated after probiotic treatment. The Lung function results also showed the improvement effects of probiotics administration. In addition, probiotics could promote the balance of Th17 and Treg cells, inhibit cytokines expression (TNF-α, IL-6, IL-1β, IL-17A), and increase the concentration of anti-inflammatory factors (IL-10, TGF-β). In addition, 16 S rRNA sequence analysis showed that probiotic treatment could reduce microbiota abundance and diversity, increase the abundance of possible beneficial bacteria, and decrease the abundance of bacteria associated with inflammation. In general, probiotic intervention was found to have preventive effects on the occurrence of PM2.5 induced pathological injury, and the mechanism was associate with to the inhibition of inflammatory response, regulation of Th17/Treg balance and maintenance of intestinal internal environment stability.

Association of SARS-CoV-2 and Polypharmacy with Gut-Lung Axis: From Pathogenesis to Treatment

SARS-CoV-2 is a novel infectious contagion leading to COVID-19 disease. The virus has affected the lives of millions of people across the globe with a high mortality rate. It predominantly affects the lung (respiratory system), but it also affects other organs, including the cardiovascular, psychological, and gastrointestinal (GIT) systems. Moreover, elderly and comorbid patients with compromised organ functioning and pre-existing polypharmacy have worsened COVID-19-associated complications. Microbiota (MB) of the lung plays an important role in developing COVID-19. The extent of damage mainly depends on the predominance of opportunistic pathogens and, inversely, with the predominance of advantageous commensals. Changes in the gut MB are associated with a bidirectional shift in the interaction among the gut with a number of vital human organs, which leads to severe disease symptoms. This review focuses on dysbiosis in the gut-lung axis, COVID-19-induced worsening of comorbidities, and the influence of polypharmacy on MB.

Limosilactobacillus reuteri SLZX19-12 Protects the Colon from Infection by Enhancing Stability of the Gut Microbiota and Barrier Integrity and Reducing Inflammation

Limosilactobacillus reuteri plays an important role in regulating intestinal functions and maintaining barrier integrity in animals. In this study, Limosilactobacillus reuteri strain SLZX19-12 was isolated from the fecal microbiota of Tibetan pigs, and it was found that this strain is sensitive to common antibiotics and has strong resistance to stress. Upon being administered by gavage at different doses, including low, medium, and high doses, for 14 days, Limosilactobacillus reuteri SLZX19-12 may enhance the intestinal barrier. After administration of a high dose of SLZX19-12, mice were challenged with Salmonella enterica serovar Typhimurium SL1344. Infection with Salmonella Typhimurium SL1344 led to disordered colonic microbiotas, colonic inflammation through the S100A8/S100A9-NF-κB pathway and potential apoptosis, and translocation of pathogens to parenteral visceral organs in mice. However, the mice pretreated with Limosilactobacillus reuteri SLZX19-12 showed lower loads of Salmonella in visceral organs, less colonic inflammation, and higher barrier integrity. More importantly, the administration of strain SLZX19-12 resulted in a more stable microbiota structure of the colon, in which the abundance of Alloprevotella was greatly enhanced. Therefore, this study suggests that Limosilactobacillus reuteri SLZX19-12 can protect the colon from infection by enhancing the stability of gut microbiota and barrier integrity and reducing inflammation. IMPORTANCE The use of antibiotics to treat bacterial infections leads to a series of side effects. As an alternative method, the biocontrol strategy, which uses probiotics to suppress pathogens, is considered a potential way to deal with bacterial infections in gut. However, there are few probiotics that are currently safe and can protect against infection. In this study, Limosilactobacillus reuteri strain SLZX19-12 was obtained from Tibetan pigs, which have higher resistance to infection. This strain is sensitive to conventional antibiotics, secretes a wide spectrum of enzymes, and also promotes the intestinal barrier function in mice. In addition, Limosilactobacillus reuteri SLZX19-12 can promote the stability of the gut microbiota to avoid or alleviate the occurrence or development of foodborne infections.

Severity of neonatal influenza infection is driven by type I interferon and oxidative stress

Neonates exhibit increased susceptibility to respiratory viral infections, attributed to inflammation at the developing pulmonary air-blood interface. IFN I are antiviral cytokines critical to control viral replication, but also promote inflammation. Previously, we established a neonatal murine influenza virus (IV) model, which demonstrates increased mortality. Here, we sought to determine the role of IFN I in this increased mortality. We found that three-day-old IFNAR-deficient mice are highly protected from IV-induced mortality. In addition, exposure to IFNβ 24 h post IV infection accelerated death in WT neonatal animals but did not impact adult mortality. In contrast, IFN IIIs are protective to neonatal mice. IFNβ induced an oxidative stress imbalance specifically in primary neonatal IV-infected pulmonary type II epithelial cells (TIIEC), not in adult TIIECs. Moreover, neonates did not have an infection-induced increase in antioxidants, including a key antioxidant, superoxide dismutase 3, as compared to adults. Importantly, antioxidant treatment rescued IV-infected neonatal mice, but had no impact on adult morbidity. We propose that IFN I exacerbate an oxidative stress imbalance in the neonate because of IFN I-induced pulmonary TIIEC ROS production coupled with developmentally regulated, defective antioxidant production in response to IV infection. This age-specific imbalance contributes to mortality after respiratory infections in this vulnerable population.

The Beneficial Role of Probiotic Lactobacillus in Respiratory Diseases

Respiratory diseases cause a high incidence and mortality worldwide. As a natural immunobiotic, Lactobacillus has excellent immunomodulatory ability. Administration of some Lactobacillus species can alleviate the symptoms of respiratory diseases such as respiratory tract infections, asthma, lung cancer and cystic fibrosis in animal studies and clinical trials. The beneficial effect of Lactobacillus on the respiratory tract is strain dependent. Moreover, the efficacy of Lactobacillus may be affected by many factors, such as bacteria dose, timing and host background. Here, we summarized the beneficial effect of administered Lactobacillus on common respiratory diseases with a focus on the mechanism and safety of Lactobacillus in regulating respiratory immunity.

Biotechnological Processes Simulating the Natural Fermentation Process of Bee Bread and Therapeutic Properties-An Overview

Recent signs of progress in functional foods and nutraceuticals highlighted the favorable impact of bioactive molecules on human health and longevity. As an outcome of the fermentation process, an increasing interest is developed in bee products. Bee bread (BB) is a different product intended for humans and bees, resulting from bee pollen's lactic fermentation in the honeycombs, abundant in polyphenols, nutrients (vitamins and proteins), fatty acids, and minerals. BB conservation is correlated to bacteria metabolites, mainly created by Pseudomonas spp., Lactobacillus spp., and Saccharomyces spp., which give lactic acid bacteria the ability to outperform other microbial groups. Because of enzymatic transformations, the fermentation process increases the content of new compounds. After the fermentation process is finalized, the meaningful content of lactic acid and several metabolites prevent the damage caused by various pathogens that could influence the quality of BB. Over the last few years, there has been an increase in bee pollen fermentation processes to unconventional dietary and functional supplements. The use of the chosen starters improves the bioavailability and digestibility of bioactive substances naturally found in bee pollen. As a consequence of enzymatic changes, the fermentation process enhances BB components and preserves them against loss of characteristics. In this aspect, the present review describes the current biotechnological advancements in the development of BB rich in beneficial components derived from bee pollen fermentation and its use as a food supplement and probiotic product with increased shelf life and multiple health benefits.

Effective Regulation of Gut Microbiota With Probiotics and Prebiotics May Prevent or Alleviate COVID-19 Through the Gut-Lung Axis

Coronavirus disease 2019 (COVID-19) can disrupt the gut microbiota balance, and patients usually have intestinal disorders. The intestine is the largest immune organ of the human body, and gut microbes can affect the immune function of the lungs through the gut-lung axis. Many lines of evidence support the role of beneficial bacteria in enhancing human immunity, preventing pathogen colonization, and thereby reducing the incidence and severity of infection. In this article, we review the possible approach of modulating microbiota to help prevent and treat respiratory tract infections, including COVID-19, and discuss the possibility of using probiotics and prebiotics for this purpose. We also discuss the mechanism by which intestinal micro-flora regulate immunity and the effects of probiotics on the intestinal micro-ecological balance. Based on this understanding, we propose the use of probiotics and prebiotics to modulate gut microbiota for the prevention or alleviation of COVID-19 through the gut-lung axis.

Probiotics protect against RSV infection by modulating the microbiota-alveolar-macrophage axis

Respiratory syncytial virus (RSV) is leading cause of respiratory tract infections in early childhood. Gut microbiota is closely related with the pulmonary antiviral immunity. Recent evidence shows that gut dysbiosis is involved in the pathogenesis of RSV infection. Therefore; pharmacological and therapeutic strategies aiming to readjust the gut dysbiosis are increasingly important for the treatment of RSV infection. In this study, we evaluated the therapeutic effects of a probiotic mixture on RSV-infected mice. This probiotic mixture consisted of Lactobacillus rhamnosus GG, Escherichia coli Nissle 1917 and VSL#3 was orally administered to neonatal mice on a daily basis either for 1 week in advance or for 3 days starting from the day of RSV infection. We showed that administration of the probiotics protected against RSV-induced lung pathology by suppressing RSV infection and exerting an antiviral response via alveolar macrophage (AM)-derived IFN-β. Furthermore, administration of the probiotics reversed gut dysbiosis and significantly increased the abundance of short-chain fatty acid (SCFA)-producing bacteria in RSV-infected mice, which consequently led to elevated serum SCFA levels. Moreover, administration of the probiotics restored lung microbiota in RSV-infected mice. We demonstrated that the increased production of IFN-β in AMs was attributed to the increased acetate in circulation and the levels of Corynebacterium and Lactobacillus in lungs. In conclusion, we reveal that probiotics protect against RSV infection in neonatal mice through a microbiota-AM axis, suggesting that the probiotics may be a promising candidate to prevent and treat RSV infection, and deserve more research and development in future.

Probiotics in Prevention and Treatment of COVID-19: Current Perspective and Future Prospects

Saving lives and flattening the curve are the foremost priorities during the ongoing pandemic spread of SARS-CoV-2. Developing cutting-edge technology and collating available evidence would support frontline health teams. Nutritional adequacy improves general health and immunity to prevent and assuage infections. This review aims to outline the potential role of probiotics in fighting the COVID-19 by covering recent evidence on the association between microbiota, probiotics, and COVID-19, the role of probiotics as an immune-modulator and antiviral agent. The high basic reproduction number (R0) of SARS-CoV-2, absence of conclusive remedies, and the pleiotropic effect of probiotics in fighting influenza and other coronaviruses together favour probiotics supplements. However, further support from preclinical and clinical studies and reviews outlining the role of probiotics in COVID-19 are critical. Results are awaited from many ongoing clinical trials investigating the benefits of probiotics in COVID-19.

Protection against neonatal respiratory viral infection via maternal treatment during pregnancy with the benign immune training agent OM-85

Objectives

Incomplete maturation of immune regulatory functions at birth is antecedent to the heightened risk for severe respiratory infections during infancy. Our forerunner animal model studies demonstrated that maternal treatment with the microbial‐derived immune training agent OM‐85 during pregnancy promotes accelerated postnatal maturation of mechanisms that regulate inflammatory processes in the offspring airways. Here, we aimed to provide proof of concept for a novel solution to reduce the burden and potential long‐term sequelae of severe early‐life respiratory viral infection through maternal oral treatment during pregnancy with OM‐85, already in widespread human clinical use.

Methods

In this study, we performed flow cytometry and targeted gene expression (RT‐qPCR) analysis on lungs from neonatal offspring whose mothers received oral OM‐85 treatment during pregnancy. We next determined whether neonatal offspring from OM‐85 treated mothers demonstrate enhanced protection against lethal lower respiratory infection with mouse‐adapted rhinovirus (vMC₀), and associated lung immune changes.

Results

Offspring from mothers treated with OM‐85 during pregnancy display accelerated postnatal seeding of lung myeloid populations demonstrating upregulation of function‐associated markers. Offspring from OM‐85 mothers additionally exhibit enhanced expression of TLR4/7 and the IL‐1β/NLRP3 inflammasome complex within the lung. These treatment effects were associated with enhanced capacity to clear an otherwise lethal respiratory viral infection during the neonatal period, with concomitant regulation of viral‐induced IFN response intensity.

Conclusion

These results demonstrate that maternal OM‐85 treatment protects offspring against lethal neonatal respiratory viral infection by accelerating development of innate immune mechanisms crucial for maintenance of local immune homeostasis in the face of pathogen challenge.

Review: The Nose as a Route for Therapy. Part 2 Immunotherapy

The nose provides a route of access to the body for inhalants and fluids. Unsurprisingly it has a strong immune defense system, with involvement of innate (e.g., epithelial barrier, muco- ciliary clearance, nasal secretions with interferons, lysozyme, nitric oxide) and acquired (e.g., secreted immunoglobulins, lymphocytes) arms. The lattice network of dendritic cells surrounding the nostrils allows rapid uptake and sampling of molecules able to negotiate the epithelial barrier. Despite this many respiratory infections, including SARS-CoV2, are initiated through nasal mucosal contact, and the nasal mucosa is a significant "reservoir" for microbes including Streptococcus pneumoniae, Neisseria meningitidis and SARS -CoV-2. This review includes consideration of the augmentation of immune defense by the nasal application of interferons, then the reduction of unnecessary inflammation and infection by alteration of the nasal microbiome. The nasal mucosa and associated lymphoid tissue (nasopharynx-associated lymphoid tissue, NALT) provides an important site for vaccine delivery, with cold-adapted live influenza strains (LAIV), which replicate intranasally, resulting in an immune response without significant clinical symptoms, being the most successful thus far. Finally, the clever intranasal application of antibodies bispecific for allergens and Intercellular Adhesion Molecule 1 (ICAM-1) as a topical treatment for allergic and RV-induced rhinitis is explained.

Modulation of Gut Microbiota for the Prevention and Treatment of COVID-19

The gut microbiota is well known to exert multiple benefits on human health including protection from disease causing pathobiont microbes. It has been recognized that healthy intestinal microbiota is of great importance in the pathogenesis of COVID-19. Gut dysbiosis caused by various reasons is associated with severe COVID-19. Therefore, the modulation of gut microbiota and supplementation of commensal bacterial metabolites could reduce the severity of COVID-19. Many approaches have been studied to improve gut microbiota in COVID-19 including probiotics, bacterial metabolites, and prebiotics, as well as nutraceuticals and trace elements. So far, 19 clinical trials for testing the efficacy of probiotics and synbiotics in COVID-19 prevention and treatment are ongoing. In this narrative review, we summarize the effects of various approaches on the prevention and treatment of COVID-19 and discuss associated mechanisms.

Impact of Probiotic Bacteria on Respiratory Allergy Disorders

Respiratory allergy is a common disease with an increased prevalence worldwide. The effective remedy is still unknown, and a new therapeutic approach is highly desirable. The review elaborates the influence of probiotic bacteria on respiratory allergy prevention and treatment with particular emphasis on the impact of the current methods of their administration – oral and intranasal. The background of the respiratory allergy is complex thus, we focused on the usefulness of probiotics in the alleviation of different allergy factors, in particular involved in pathomechanism, local hypersensitive evidence and the importance of epithelial barrier. In this review, we have shown that (1) probiotic strains may vary in modulatory potential in respiratory allergy, (2) probiotic bacteria are beneficial in oral and intranasal administration, (3) recombinant probiotic bacteria can modulate the course of respiratory allergy.

Application of weighted gene co-expression network analysis to identify the hub genes in H1N1

OBJECTIVE

Identifying the disease-associated interactions between different genes helps us to find novel therapeutic targets and predictive biomarkers.

METHODS

Gene expression data GSE82050 from H1N1 and control human samples were acquired from the NCBI GEO database. Highly co-expressed genes were grouped into modules. Through Person's correlation coefficient calculation between the module and clinical phenotype, notable modules were identified. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses were conducted, and the hub genes within the module of interest were identified. Also, gene expression data GSE27131 were acquired from the GEO database to verify differential key gene expression analysis. The CIBERSORT was used to evaluate the immune cells infiltration and the GSVA was performed to identify the differentially regulated pathways in H1N1. The receiver operating characteristic (ROC) curves were used to assess the diagnostic values of the hub genes.

RESULT

The black module was shown to have the highest correlation with the clinical phenotype, mainly functioning in the signaling pathways such as the mitochondrial inner membrane, DNA conformation change, DNA repair, and cell cycle phase transition. Through analysis of the black module, we found 5 genes that were highly correlated with the H1N1 phenotype. The H1N1 project from GSE27131 confirmed an increased expression of these genes.

CONCLUSION

By using the WGCNA we analyzed and predicted the key genes in H1N1. BRCA1, CDC20, MAD2L1, MCM2, and UBE2C were found to be the most relevant genes, which may be therapeutic targets and predictive biomarkers for H1N1 therapy.

The microbiome in atopic patients and potential modifications in the context of the severe acute respiratory syndrome coronavirus 2 pandemic

PURPOSE OF REVIEW

Data regarding the effects of coronavirus disease 2019 (COVID-19) on host-microbiome alteration and subsequent effects on susceptibility and clinical course of COVID-19, especially in atopic patients, are currently limited. Here, we review the studies regarding the microbiome of atopic patients with other respiratory infections and discuss the potential role of probiotics as therapeutic targets for COVID-19 to decrease its susceptibility and severity of COVID-19.

RECENT FINDINGS

Respiratory tract virus infection affects the gut and airway microbiome structures and host's immune function. Diverse factors in atopic diseases affect the airway and gut microbiome structures, which are expected to negatively influence host health. However, response to respiratory virus infection in atopic hosts depends on the preexisting microbiome and immune responses. This may explain the inconclusiveness of the effects of COVID-19 on the susceptibility, morbidity, and mortality of patients with atopic diseases. Beneficial probiotics may be a therapeutic adjuvant in COVID-19 infection as the beneficial microbiome can decrease the viral load in the early phase of respiratory virus infection and improve the morbidity and mortality.

SUMMARY

Application of probiotics can be a potential adjuvant treatment in respiratory virus infection to improve host immune responses and disturbed microbiome structures in atopic patients. Further related studies involving COVID-19 are warranted in near future.

Topical Microbial Therapeutics against Respiratory Viral Infections

Emerging evidence suggests that microbial therapeutics can prevent and treat respiratory viral diseases, especially when applied directly to the airways. This review presents established beneficial effects of locally administered microbial therapeutics against respiratory viral diseases and the inferred related molecular mechanisms. Several mechanisms established in the intestinal probiotics field as well as novel, niche-specific insights are relevant in the airways. Studies at cellular and organism levels highlight biologically plausible but strain-specific and host and virus context-dependent mechanisms, underlying the potential of beneficial bacteria. Large-scale clinical studies can now be rationally designed to provide a bench-to-bedside translation of the multifactorial bacterial mechanisms within the host respiratory tract, to diminish the incidence and severity of viral infections and the concomitant complications.

Akkermansia muciniphila Improves Host Defense Against Influenza Virus Infection

Influenza virus infection can alter the composition of the gut microbiota, while its pathogenicity can, in turn, be highly influenced by the gut microbiota. However, the details underlying these associations remain to be determined. The H7N9 influenza virus is an emerging zoonotic pathogen which has caused the death of 616 humans and has incurred huge losses in the poultry industry. Here, we investigated the effects of infection with highly pathogenic H7N9 on gut microbiota and determined potential anti-influenza microbes. 16S rRNA sequencing results show that H7N9 infection alters the mouse gut microbiota by promoting the growth of Akkermansia, Ruminococcus 1, and Ruminococcaceae UCG-010, and reducing the abundance of Rikenellaceae RC9 gut group and Lachnoclostridium. Although the abundance of Akkermansia muciniphila is positively related to H7N9 infection, the oral administration of cultures, especially of pasteurized A. muciniphila, can significantly reduce weight loss and mortality caused by H7N9 infection in mice. Furthermore, oral administration of live or pasteurized A. muciniphila significantly reduces pulmonary viral titers and the levels IL-1β and IL-6 but enhances the levels of IFN-β, IFN-γ, and IL-10 in H7N9-infected mice, suggesting that the anti-influenza role of A. muciniphila is due to its anti-inflammatory and immunoregulatory properties. Taken together, we showed that the changes in the gut microbiota are associated with H7N9 infection and demonstrated the anti-influenza role of A. muciniphila, which enriches current knowledge about how specific gut bacterial strains protect against influenza infection and suggests a potential anti-influenza probiotic.

Anti-Influenza virus effects of Enterococcus faecalis KH2 and Lactobacillus plantarum SNK12 RNA

Bacterial RNA has recently emerged as an immune-stimulating factor during viral infection. The immune response in an organism is directly related to the progression of virus infections. Lactic acid bacteria in particular have anticancer, bioprotective, and antiallergic effects by modulating immunity. Here, we aimed to demonstrate the effect of bacterial RNA on in vitro production of IL-12, a proinflammatory cytokine, and on in vivo activity against influenza A virus (IFV) infection. Oral administration of heat-killed Enterococcus faecalis KH2 (KH2) or Lactobacillus plantarum SNK12 (SNK) in IFV-infected mice suppressed viral replication and stimulated production of virus-specific antibodies. However, ribonuclease-treated KH2 or SNK abrogated the effect, reducing IL-12 production in vitro and anti-IFV effects in vivo. Taken together, KH2 or SNK showed antiviral effects in vivo when administered orally, and the RNAs of KH2 and SNK play a part in these effects, despite the phylogenetic differences between the bacteria.

Is it time for microbiome-based therapies in viral infections?

Infectious diseases related to viruses, as well as bacterial pathogens, abound in all parts of the world, burdening health and economy. Thus, there is a dire need to find new prevention and treatment strategies to improve clinical practices related to viral infections. Human gut contains trillions of bacteria which have regulatory roles in immune development, homeostasis, and body metabolism. Today, it is difficult to find any prominent viral infection that hasn't had any link with the human gut microbiota. In this opinion-based review article, I argued the significance of manipulating human gut microbiota as novel therapeutics through probiotics or FMT in alleviating complexities related to viral infections, and pinpointed bottlenecks involved in this research.

The relevance of nutrition as a step forward to combat COVID-19

A new type of single-stranded RNA virus that belongs to the coronavirus’s family named SARS-CoV-2 has recently appeared, with fast-growing human to human transmissions. This virus has posed an important global health threat. Many nutrients can support the immune system and help in preventing or in ameliorating the response to viral infections. In the case of COVID-19, the unique pathophysiology of the coronavirus needs to be understood, in order to determine whether any potential nutrition intervention is indicated. A literature survey that comprised of ongoing research was conducted to evaluate the benefits of the bioactives present in food, such as: plant-derived extracts, vitamins, minerals, probiotics, and prebiotics, against the mechanisms of the COVID-19 infection. Although no food is yet confirmed to help in the prevention or in the treatment of the coronavirus transmission alone, exploring the possible implications of nutrition-infection interrelationships is of utmost importance. Well-designed and controlled clinical studies are emerging to explain whether the higher consumption of fruits, vegetables, protein-rich foods, unsaturated fatty acids, and other natural functional foods may aid in combating the COVID-19 infection. Meanwhile, a healthy and balanced diet is traditionally practised in viral infections that support the healthy gut microbiota profile. The human immune system function should be a vital prophylactic measure, along with adequate physical activities and sleeping habits. The consumption of immune-supportive nutrients is also encouraged in the elderly, comorbid, and in the immune-compromised as well as in malnourished individuals, in order to minimise the complications and the negative outcomes that are associated with the COVID-19 disease. Keywords: COVID-19 nutrition, mаcronutrients, micronutrients, bioactive compounds, malnutrition

Review article: Probiotics, prebiotics and dietary approaches during COVID-19 pandemic

Background

Patients with COVID-19 caused by SARS-CoV-2 exhibit diverse clinical manifestations and severity including enteric involvement. Commensal gut bacteria can contribute to defense against potential pathogens by promoting beneficial immune interactions. Interventions targeting the gut microbiome may have systemic anti-viral effects in SARS-CoV-2 infection.

Scope and approach

To summarise alterations of gut microbiota in patients with COVID-19 including impact of specific bacteria on disease severity, discuss current knowledge on the role of probiotics, prebiotics and dietary approaches including vitamin D in preventing and reducing disease susceptibility and review clinical studies using probiotics to target coronavirus. A literature review on SARS-CoV-2, COVID-19, gut microbiome and immunity was undertaken and relevant literature was summarised and critically examined.

Key findings and conclusions

Integrity of gut microbiome was perturbed in SARS-CoV-2 infections and associated with disease severity. Poor prognosis in SARS-CoV-2 infection was observed in subjects with underlying co-morbidities who had increased gut permeability and reduced gut microbiome diversity. Dietary microbes, including probiotics or selected prebiotics of Chinese origin, had anti-viral effects against other forms of coronavirus, and could positively impact host immune functions during SARS-CoV-2 infection. Numerous studies are investigating the role of probiotics in preventing and reducing susceptibility to SARS-CoV-2 infection in healthcare workers, household contacts and affected patients. An approach to strengthen intestinal barrier and lower pro-inflammatory states by adopting a more diversified diet during COVID-19 pandemic.

SARS-CoV-2 infection is associated with immune dysfunction and gut microbiota alterations. Delineating mechanisms of probiotics, prebiotics and diet with anti-SARS-CoV-2 immunity present opportunities for discovery of microbial therapeutics to prevent and treat COVID-19.

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SARS-CoV-2 infection resulted in immune dysfunction and gut microbiota alterations.

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Probiotics or prebiotics could improve host immune functions during the infection.

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Enhance gut barrier by diversified diet was recommended during COVID-19 pandemic.

Challenges for the Newborn Following Influenza Virus Infection and Prospects for an Effective Vaccine

Newborns are at significantly increased risk of severe disease following infection with influenza virus. This is the collective result of their naïve status, altered immune responsiveness, and the lack of a vaccine that is effective in these individuals. Numerous studies have revealed impairments in both the innate and adaptive arms of the immune system of newborns. The consequence of these alterations is a quantitative and qualitative decrease in both antibody and T cell responses. This review summarizes the hurdles newborns experience in mounting an effective response that can clear influenza virus and limit disease following infection. In addition, the challenges, as well as the opportunities, for developing vaccines that can elicit protective responses in these at risk individuals are discussed.

Short Communication: Oral Administration of Heat-killed Lactobacillus brevis KB290 in Combination with Retinoic Acid Provides Protection against Influenza Virus Infection in Mice

Influenza virus type A (IAV) is a seasonal acute respiratory disease virus with severe symptoms, and an effective preventive measure is required. Despite many reports describing the potentially protective effects of lactic acid bacteria, few studies have investigated the effects of nutritional supplement combinations. This study reports the effect of the combined intake of heat-killed Lactobacillus brevis KB290 (KB290) and vitamin A (VA) on mice challenged with a sublethal dose of IAV. For 2 weeks, five groups of mice were fed either placebo, KB290, VA, or a combination of KB290 and VA (KB290+VA). After subsequent IAV challenge, bodyweight and general health were monitored for up to 2 weeks. Viral titres were determined in the lungs of animal subgroups euthanised at days 3, 7, and 14 after IAV challenge. A significant loss was observed in the bodyweights of IAV-infected animals from day 1 post-IAV challenge, whereas the mice fed KB290+VA did not lose any weight after IAV infection, indicating successful protection from the infection. Additionally, mice in the KB290+VA group showed the highest reduction in lung viral titres. In conclusion, the combination of KB290 and VA could be a useful food supplement relevant for protection against seasonal influenza virus infection in humans.

Precise engineering of neutrophil membrane coated with polymeric nanoparticles concurrently absorbing of proinflammatory cytokines and endotoxins for management of sepsis

Sepsis, ensuing from unrestrained inflammatory replies to bacterial infections, endures with high injury and mortality worldwide. Presently, active sepsis management is missing in the hospitals during the surgery, and maintenance remnants mainly helpful. Now, we have constructed the macrophage bio-mimic nanoparticles for the treatment of sepsis and its management. Biomimetic macrophage nanoparticles containing a recyclable polymeric nanoparticle covered with cellular membrane resulting from macrophages (represented PEG-Mac@NPs) have an antigenic external similar to the cells. The PEG-Mac@NPs, Isorhamnetin (Iso) on the free LPS encouraged endotoxin in BALB/c mice through evaluating the nitric acid, TNF-α, and IL-6. Further, the COX-2 and iNOS expression ratio was examined to recognize the connection of several trails to find the exact mode of action PEG-Mac@NPs and Iso. The outcome reveals that the PEG-Mac@NPs inhibited and LPS triggered the NO production though the macrophages peritoneal. Furthermore, the anti-inflammatory possessions were additionally categorized through the reduction of COX-2 and iNOS protein expressions. Engaging PEG-Mac@NPs as a biomimetic decontamination approach displays potential for refining sepsis patient consequences, possibly in the use of sepsis management.