Mucosal Surfaces Research Articles

The immunobiology of corneal HSV-1 infection and herpetic stromal keratitis.

SUMMARYHuman alphaherpesvirus 1 (HSV-1) is a highly successful neurotropic pathogen that primarily infects the epithelial cells lining the orofacial mucosa. After primary lytic replication in the oral, ocular, and nasal mucosal epithelial cells, HSV-1 establishes life-long latency in neurons within the trigeminal ganglion. Patients with compromised immune systems experience frequent reactivation of HSV-1 from latency, leading to virus entry in the sensory neurons, followed by anterograde transport and lytic replication at the innervated mucosal epithelial surface. Although recurrent infection of the corneal mucosal surface is rare, it can result in a chronic immuno-inflammatory condition called herpetic stromal keratitis (HSK). HSK leads to gradual vision loss and can cause permanent blindness in severe untreated cases. Currently, there is no cure or successful vaccine to prevent latent or recurrent HSV-1 infections, posing a significant clinical challenge to managing HSK and preventing vision loss. The conventional clinical management of HSK primarily relies on anti-virals to suppress HSV-1 replication, anti-inflammatory drugs (such as corticosteroids) to provide symptomatic relief from pain and inflammation, and surgical interventions in more severe cases to replace damaged cornea. However, each clinical treatment strategy has limitations, such as local and systemic drug toxicities and the emergence of anti-viral-resistant HSV-1 strains. In this review, we summarize the factors and immune cells involved in HSK pathogenesis and highlight alternate therapeutic strategies for successful clinical management of HSK. We also discuss the therapeutic potential of immunoregulatory cytokines and immunometabolism modulators as promising HSK therapies against emerging anti-viral-resistant HSV-1 strains.

Endoscopic Retrograde Cholangiopancreatography-Related Procedures for the Differential Diagnosis of Isolated Immunoglobin G4-Related Sclerosing Cholangitis and Perihilar Cholangiocarcinoma.

Differential diagnosis of isolated immunoglobin (Ig)G4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma is challenging. We aimed to clarify the role of endoscopic retrograde cholangiography (ERCP)-related procedures in the differential diagnosis of isolated IgG4-SC and perihilar cholangiocarcinoma (PHCC). Seven patients with hilar-type isolated IgG4-SC diagnosed at Hiroshima University Hospital and sixty-five patients with surgically resected invasive PHCC were enrolled, and the diagnostic yields of intraductal ultrasonography (IDUS), peroral cholangioscopy (POCS), and pathological examinations were determined. In six of seven (86%) patients with isolated IgG4-SC, the stricture was in the perihilar bile duct. IDUS showed that symmetrical wall thickening (40% vs. 5%, p = 0.04), homogeneous internal echo (80% vs. 5%, p < 0.001), and smooth outer margins (80% vs. 6%, p < 0.001) were more frequent in isolated IgG4-SC than in PHCC. POCS showed a smooth mucosal surface more frequent in isolated IgG4-SC (75% vs. 7%, p = 0.006). Only one patient had two pathological findings characteristic of IgG4-SC. The sensitivity for diagnosing PHCC was 81% using two or more combined sampling methods. Pathological examinations have limitations in the differential diagnosis of isolated-IgG4-SC and PHCC, and a diagnostic strategy that combines multiple ERCP-related procedures, including IDUS and POCS, is recommended.

Mucosal IFNλ1 mRNA-based immunomodulation effectively reduces SARS-CoV-2 induced mortality in mice

RNA vaccines elicit protective immunity against SARS-CoV-2, but the use of mRNA as an antiviral immunotherapeutic is unexplored. Here, we investigate the activity of lipidoid nanoparticle (LNP)-formulated mRNA encoding human IFNλ1 (ETH47), which is a critical driver of innate immunity at mucosal surfaces protecting from viral infections. IFNλ1 mRNA administration promotes dose-dependent protein translation, induction of interferon-stimulated genes without relevant signs of unspecific immune stimulation, and dose-dependent inhibition of SARS-CoV-2 replication in vitro. Pulmonary administration of IFNλ1 mRNA in mice results in a potent reduction of virus load, virus-induced body weight loss and significantly increased survival. These data support the development of inhaled administration of IFNλ1 mRNA as a potential prophylactic option for individuals exposed to SARS-CoV-2 or at risk suffering from COVID-19. Based on the broad antiviral activity of IFNλ1 regardless of virus or variant, this approach might also be utilized for other respiratory viral infections or pandemic preparedness.

Detection and consistency of mucosal fluid T lymphocyte phenotypes and their relationship with blood, age and gender

Innate and adaptive immune responses at mucosal surfaces play a role in protection against most infectious diseases. However, the relative importance either of mucosal versus systemic, or of cellular versus humoral immunity in protection against such infections remains unclear. We aimed to determine the relative percentages and reproducibility of detection of five major T lymphocyte phenotypes in stimulated whole mouth fluid (SWMF); to compare matched mucosal and blood phenotypes; to evaluate the consistency of phenotypes in SWMF over time; and to determine any associations with age or gender. Peripheral blood and SWMF samples were collected from 194 participants and sequential concomitant samples were collected from 27 of those and from 12 subjects living with HIV. CD3, CD4, CD8, Th1 and Th2 T lymphocyte phenotypes were determined by FACS. All the five T lymphocyte phenotypes were detected consistently by FACS in PBMC and SWMF with experimental replicates (N = 10; PBMC CV: 3–30%; SWMF CV: 12–36%). In longitudinal samples detection rates were reproducible in both fluids but variations were higher in SWMF (CV: 23–79.6%) than PBMC (CV: 9.7–75%). Statistically significant correlations of the percentages of all the T lymphocyte phenotypes except CD8 was seen between the two fluids. In PBMCs a negative correlation with age was found with CD3, CD4 and CD8 phenotypes, whilst a positive correlation was found in both SWMF and PBMC with the Th2 phenotype. CD3, CD4 and CD8 phenotypes in SWMF and PBMCs from an HIV-positive cohort were not significantly correlated in contrast with the HIV-negative controls. Our study provides a robust FACS protocol for the detection of the five major T lymphocyte phenotypes in SWMF which should prove useful for research with other mucosal fluids.

Stem cells, Notch-1 signaling, and oxidative stress: a hellish trio in cancer development and progression within the airways. Is there a role for natural compounds?

Notch-1 signaling plays a crucial role in stem cell maintenance and in repair mechanisms in various mucosal surfaces, including airway mucosa. Persistent injury can induce an aberrant activation of Notch-1 signaling in stem cells leading to an increased risk of cancer initiation and progression. Chronic inflammatory respiratory disorders, including chronic obstructive pulmonary disease (COPD) is associated with both overactivation of Notch-1 signaling and increased lung cancer risk. Increased oxidative stress, also due to cigarette smoke, can further contribute to promote cancer initiation and progression by amplifying inflammatory responses, by activating the Notch-1 signaling, and by blocking regulatory mechanisms that inhibit the growth capacity of stem cells. This review offers a comprehensive overview of the effects of aberrant Notch-1 signaling activation in stem cells and of increased oxidative stress in lung cancer. The putative role of natural compounds with antioxidant properties is also described.

EVALUATION OF CANDIDA SPP. ADHERENCE TO 3D-PRINTED AND HEAT-CURED PMMA RESIN DENTURES

Introduction: Despite the progress of additive manufacturing, there are different opinions regarding microbial adhesion on the surface of 3D printed dentures and the biocompatiability of the materials. The purpose of this in-vivo study was to determine the presence of Candida species in the saliva, oral mucosa and on dentures of patients wearing heat-cured polymethylmethacrylate (PMMA) and 3D-printed prosthetic appliances after a three-month period of observation. Materials and methods: The clinical study included 40 edentulous patients, divided into two groups - first group (A) –wearing conventional dentures and second group (B) – wearing 3D printed dentures. It was used chrom agar Candida (Bio Merieux) for identification and quantity assessment of the presence of Candida spp. and spectrophotometric analysis using VITEK MS (Bio Merieux). Results: After three months of wearing the dentures, Candida spp was not isolated in the saliva in 60% of patients in group A and 70% of group B, with no statistically significant difference between the results before the treatment and after the third month. In the third month, Candida spp was isolated from the oral mucosa of 20% of group A and in group B – 10%, with no significant difference between the groups (p&lt;0.05). No Candida spp was isolated from 90% of denture surfaces in both groups. Conclusion: The adhesion of Candida spp. to 3D printed dentures is not higher than conventional dentures made from heat-curing resin. Also, there is no difference between the amount of Candida spp. in the saliva, oral mucosa and denture surfaces.

Pre-surgical Tumor Marking by Tattooing in Patients Offered with Neoadjuvant Chemotherapy (Nact) for Advance Staged Oral Carcinomas.

We described a novel technique of marking the oral squamous cell carcinoma (OSCC) tumors before the pre-operative neoadjuvant chemotherapy (NACT). The pre-operative NACT may shrink the tumor, making it difficult for the oncosurgeon to identify the pre-NACT tumor area to be included in the surgical resection. Difficulty lies in exact topographic replication/documentation of examination findings on superficial or mucosal surface levels, primarily due to limited surface landmarks. This technique helps to identify the pre-NACT tumor margins during surgical resection and to achieve maximum oncological safety and refining surgical planning.

Neuronal expression of herpes simplex virus-1 VP16 protein induces pseudorabies virus escape from silencing and reactivation.

Alpha herpesvirus (α-HV) particles enter their hosts from mucosal surfaces and efficiently maintain fast transport in peripheral nervous system (PNS) axons to establish infections in the peripheral ganglia. The path from axons to distant neuronal nuclei is challenging to dissect due to the difficulty of monitoring early events in a dispersed neuron culture model. We have established well-controlled, reproducible, and reactivateable latent infections in compartmented rodent neurons by infecting physically isolated axons with a small number of viral particles. This system not only recapitulates the physiological infection route but also facilitates independent treatment of isolated cell bodies or axons. Consequently, this system enables study not only of the stimuli that promote reactivation but also the factors that regulate the initial switch from productive to latent infection. Adeno-associated virus (AAV)-mediated expression of herpes simplex-1 (HSV-1) VP16 alone in neuronal cell bodies enabled the escape from silencing of incoming pseudorabies virus (PRV) genomes. Furthermore, the expression of HSV VP16 alone reactivated a latent PRV infection in this system. Surprisingly, the expression of PRV VP16 protein supported neither PRV escape from silencing nor reactivation. We compared transcription transactivation activity of both VP16 proteins in primary neurons by RNA sequencing and found that these homolog viral proteins produce different gene expression profiles. AAV-transduced HSV VP16 specifically induced the expression of proto-oncogenes including c-Jun and Pim2. In addition, HSV VP16 induces phosphorylation of c-Jun in neurons, and when this activity is inhibited, escape of PRV silencing is dramatically reduced.IMPORTANCEDuring latency, alpha herpesvirus genomes are silenced yet retain the capacity to reactivate. Currently, host and viral protein interactions that determine the establishment of latency, induce escape from genome silencing or reactivation are not completely understood. By using a compartmented neuronal culture model of latency, we investigated the effect of the viral transcriptional activator, VP16 on pseudorabies virus (PRV) escape from genome silencing. This model recapitulates the physiological infection route and enables the study of the stimuli that regulate the initial switch from a latent to productive infection. We investigated the neuronal transcriptional activation profiles of two homolog VP16 proteins (encoded by HSV-1 or PRV) and found distinct gene activation signatures leading to diverse infection outcomes. This study contributes to understanding of how alpha herpesvirus proteins modulate neuronal gene expression leading to the initiation of a productive or a latent infection.

Nanoparticle-Mediated Mucosal Vaccination: Harnessing Nucleic Acids for Immune Enhancement.

Recent advancements in in vitro transcribed mRNA (IVT-mRNA) vaccine manufacturing have attracted considerable interest as advanced methods for combating viral infections. The respiratory mucosa is a primary target for pathogen attack, but traditional intramuscular vaccines are not effective in generating protective ion mucosal surfaces. Mucosal immunization can induce both systemic and mucosal immunity by effectively eliminating microorganisms before their growth and development. However, there are several biological and physical obstacles to the administration of genetic payloads, such as IVT-mRNA and DNA, to the pulmonary and nasal mucosa. Nucleic acid vaccine nanocarriers should effectively protect and load genetic payloads to overcome barriers i.e., biological and physical, at the mucosal sites. This may aid in the transfection of specific antigens, epithelial cells, and incorporation of adjuvants. In this review, we address strategies for delivering genetic payloads, such as nucleic acid vaccines, that have been studied in the past and their potential applications.

Ionic liquid-based formulation approaches for enhanced transmucosal drug delivery

The utilization of ionic liquids (ILs) in pharmaceutical drug delivery applications has seen significant expansion in recent years, owing to their distinctive characteristics and inherent adjustability. These innovative compounds can be used to tackle challenges associated with traditional dosage forms, such as polymorphism, inadequate solubility, permeability, and efficacy in topical drug delivery systems. Here, we provide a brief classification of ILs, and their effectiveness in augmenting transmucosal drug delivery approaches by improving the solubility and permeability of active pharmaceutical ingredients (APIs) by temporary mucus modulation aiding the paracellular transport of APIs, prolonging drug retention, and, thus, aiding controlled drug release across various mucosal surfaces. We also highlight potential advances in, and future perspectives of, IL-based formulations in mucosal drug delivery.

Mucosal signatures of pathogenic T cells in HLA-B*27+ anterior uveitis and axial spondyloarthritis.

HLA-B*27 was one of the first HLA alleles associated with an autoimmune disease, i.e., axial spondyloarthritis (axSpA) and acute anterior uveitis (B27AAU), which cause joint and eye inflammation, respectively. Gastrointestinal inflammation has been suggested as a trigger of axSpA. We recently identified a bacterial peptide (YeiH) that can be presented by HLA-B*27 to expanded public T cell receptors (TCRs) in the joint in axSpA and the eye in B27AAU. While YeiH is present in enteric microbiota and pathogens, additional evidence that pathogenic T cells in HLA-B*27-associated autoimmunity may have had a prior antigenic encounter within the gastrointestinal tract remains lacking. Here, we analyze ocular, synovial, and blood T cells in B27AAU and axSpA, showing that YeiH-specific CD8 T cells express a mucosal gene set and surface proteins consistent with intestinal differentiation, including CD161, integrin α4β7, and CCR6. In addition, we find an expansion of YeiH-specific CD8 T cells in the blood of axSpA and B27AAU over healthy controls, whereas influenza-specific CD8 T cells were equivalent across groups. Lastly, we demonstrate the dispensability of TRBV9 for antigen recognition. Collectively, our data suggest that, in HLA-B27-associated autoimmunity, early antigen exposure and differentiation of pathogenic CD8 T cells may occur in enteric organs.

IgA class-switched CD27-CD21+ B cells in IgA nephropathy.

IgA nephropathy (IgAN) is characterised by the production of galactose-deficient IgA1 (GdIgA1) antibodies. As the source of pathogenic antibodies, B cells are central to IgAN pathogenesis, but the B cell activation pathways as well as the potential B cell source of dysregulated IgA-secretion remain unknown. We carried out flow cytometry analysis of peripheral blood B cells in patients with IgA nephropathy and control subjects with a focus on IgA-expressing B cells to uncover the pathways of B cell activation in IgAN and how these could give rise to pathogenic GdIgA1 antibodies. In addition to global changes in the B cell landscape - expansion of naive and reduction in memory B cells - IgAN patients present with an increased frequency of IgA-expressing B cells that lack the classical memory marker CD27, but are CD21pos. IgAN patients further have an expanded population of IgApos antibody-secreting cells, which correlate with serum IgA levels. Both IgApos plasmabalsts and CD27neg B cells co-express GdIgA1. Implicating dysregulation at mucosal surfaces as the driver of such B cell differentiation, we found a correlation between lipopolysaccharide (LPS) in the serum and IgAposCD27neg B cell frequency. We propose that dysregulated immunity in the mucosa may drive de novo B cell activation within germinal centres, giving rise to IgAposCD27neg B cells and subsequently IgA-producing plasmablasts. These data integrate B cells into the paradigm of IgAN pathogenesis and allow to further investigate this pathway to uncover biomarkers and develop therapeutic interventions.

Development of systemic and mucosal immune responses against gut microbiota in early life and implications for the onset of allergies.

The early microbial colonization of human mucosal surfaces is essential for the development of the host immune system. Already during pregnancy, the unborn child is prepared for the postnatal influx of commensals and pathogens via maternal antibodies, and after birth this protection is continued with antibodies in breast milk. During this critical window of time, which extends from pregnancy to the first year of life, each encounter with a microorganism can influence children's immune response and can have a lifelong impact on their life. For example, there are numerous links between the development of allergies and an altered gut microbiome. However, the exact mechanisms behind microbial influences, also extending to how viruses influence host-microbe interactions, are incompletely understood. In this review, we address the impact of infants' first microbial encounters, how the immune system develops to interact with gut microbiota, and summarize how an altered immune response could be implied in allergies.

Granulicatella adiacens Bacterial Infection After Pancreatectomy Whipple's Procedure.

Background: Granulicatella adiacens inhabits the oral cavity, urogenital, and gastrointestinal tracts and is a typical commensal of human mucosal surfaces. It rarely causes disease. Identification of these gram-positive cocci can be challenging. Case Report: In a 58-year-old male in an oncology center, we report the first occurrence of bacterial infection caused by G. adiacens. After a precise diagnosis of the infection, the patient received effective treatment. Conclusion: Owing to a lack of sufficient diagnostic tools, G. adiacens may be a more notable pathogen than has been previously identified. Sensitivity testing standards are desperately needed.

Silk Fibroin Microneedles Loaded with Lipopolysaccharide-Pretreated Bone Marrow Mesenchymal Stem Cell-Derived Exosomes for Oral Ulcer Treatment.

Oral ulcers, superficial lesions on the surface of the oral mucosa, have a high incidence rate, and their main symptoms include local pain and erosion. Lipopolysaccharide (LPS)-preconditioned bone marrow mesenchymal stem cells and their secreted exosomes (LPS-pre-Exos) have been shown to promote recovery in various inflammatory conditions and wounds. However, studies documenting LPS-pre-Exos as a therapeutic intervention for oral mucosal-like diseases are lacking. In this study, we prepared a silk fibroin microneedle (MN) patch consisting of LPS-pre-Exos and zeolitic imidazolate framework-8 (ZIF-8) that localized at the tip and base, respectively, and used this MN patch for oral ulcer treatment. Upon insertion into the oral mucosa, continuous LPS-pre-Exos release was observed, which promoted macrophage polarization and tissue healing. Additionally, the ZIF-8 framework in the MN patch facilitated the controlled release of Zn2+, which demonstrated potent antimicrobial properties via synergistic effects. The in vitro experimental results showed that the silk fibroin MN patch can continuously release LPS-pre-Exos and Zn2+ for more than 7 days. Thus, the LPS-pre-Exos and ZIF-8-loaded silk fibroin MN patch exhibited good anti-inflammatory and antibacterial properties, promoting oral ulcer healing, and showed good histocompatibility. Hence, it may represent a potentially valuable strategy for facilitating oral ulcer healing.

Dual cross-linking mechanism of sodium alginate composite hydrogel for adhesive microneedle patch preparation

The introduction of microneedles has revolutionized transdermal drug delivery. However, solid microneedle patches often fail to conform to the epidermis and adapt to changes in skin curvature, limiting their effectiveness. Using sodium alginate hydrogel to create flexible microneedle patches can address this issue, but conventional sodium alginate hydrogels suffer from inhomogeneous structure, dehydration, and poor mechanical properties. These drawbacks result in reduced drug delivery efficacy and insufficient mechanical robustness. To enhance the performance of sodium alginate hydrogels, this study presents a novel sodium alginate composite hydrogel with a dual cross-linking mechanism. The hydrogel, with a gelatin to sodium alginate ratio of 1:1, exhibited optimal surface morphology and mechanical properties suitable for microneedle patch preparation. The resulting microneedle patch demonstrated excellent water adhesion, securely attaching to skin and oral mucosa surfaces. In vitro experiments confirmed the microneedle's ability to puncture and release the drug, dissolving and releasing the drug within 15 minutes. The patch also showed superior piercing and dissolution properties on the mouth palate, highlighting it may serve as a potential delivery location for more efficient microneedle patch drug administration. In the future, this technology will show great potential in expanding the scope of drug administration for transdermal drug delivery and in reducing the work pressure of healthcare professionals.

Role of ERG11 and MDR1 genes in cycloheximide and multidrug resistance in Candida species.

Candida species are amongst the commensals of the mucosal surfaces of the human body which include the oral cavity, vagina, and intestinal mucosa. Fungal infections are on the rise worldwide. The overall burden of infections due to fungi is difficult to estimate because the majority of them remain undiagnosed. The present study aims to determine the burden of antifungal resistance in low socioeconomic country, Pakistan and the frequency of ERG11 and MDR1 genes involved. A total of 636 Candida isolates were obtained from various tertiary care institutions in Lahore in the form of culture on various culture plates. Sabouraud agar culture plates were used to culture the Candida spp. Antifungal resistance was determined against Fluconazole, Itraconazole, Ketoconazole, and Nystatin via disk diffusion technique. Most resistance was observed against Fluconazole followed by Itraconazole, Ketoconazole, and Nystatin. The Candida isolates recovering from CVP tip and tissue have a high resistance profile. Candida species resistant to at least two antifungals were chosen for further ERG11 and MDR1 detection through real-time PCR. Among 255 Candida isolates, 240 contained ERG11 gene while MDR1 gene is present in 149 Candida isolates. The isolates carrying both genes were tested by the broth microdilution technique for the susceptibility against cycloheximide, all of them were able to grow in cycloheximide. The genetic determinants of antifungal resistance such as ERG11 and MDR1 are as important in the multidrug resistance against a variety of compounds and antifungal drugs.

Dual species transcriptomics reveals conserved metabolic and immunologic processes in interactions between human neutrophils and Neisseria gonorrhoeae.

Neisseria gonorrhoeae (the gonococcus, Gc) causes the sexually transmitted infection gonorrhea. Gc is a prominent threat to human health by causing severe lifelong sequelae, including infertility and chronic pelvic pain, which is amplified by the emergence of "superbug" strains resistant to all current antibiotics. Gc is highly adapted to colonize human mucosal surfaces, where it survives despite initiating a robust inflammatory response and influx of polymorphonuclear leukocytes (PMNs, neutrophils) that typically clear bacteria. Here, dual-species RNA-sequencing was used to define Gc and PMN transcriptional profiles alone and after infection. Core host and bacterial responses were assessed for two strains of Gc and three human donors' PMNs. Comparative analysis of Gc transcripts revealed overlap between Gc responses to PMNs, iron, and hydrogen peroxide; 98 transcripts were differentially expressed across both Gc strains in response to PMN co-culture, including iron-responsive and oxidative stress response genes. We experimentally determined that the iron-dependent TbpB is suppressed by PMN co-culture, and iron-limited Gc have a survival advantage when cultured with PMNs. Analysis of PMN transcripts modulated by Gc infection revealed differential expression of genes driving cell adhesion, migration, inflammatory responses, and inflammation resolution pathways. Production of pro-inflammatory cytokines, including IL1B and IL8, the adhesion factor ICAM1, and prostaglandin PGE2 were induced in PMNs in response to Gc. Together, this study represents a comprehensive and experimentally validated dual-species transcriptomic analysis of two isolates of Gc and primary human PMNs that gives insight into how this bacterium survives innate immune onslaught to cause disease.

Intranasal Immunization of Pneumococcal pep27 Mutant Attenuates Allergic and Inflammatory Diseases by Upregulating Skin and Mucosal Tregs.

Conventional immunization methods such as intramuscular injections lack effective mucosal protection against pathogens that enter through the mucosal surfaces. Moreover, conventional therapy often leads to adverse events and compromised immunity, followed by complicated outcomes, leading to the need to switch to other options. Thus, a need to develop safe and effective treatment with long-term beneficial outcomes to reduce the risk of relapse is mandatory. Mucosal vaccines administered across mucosal surfaces, such as the respiratory or intestinal mucosa, to prompt robust localized and systemic immune responses to prevent the public from acquiring pathogenic diseases. Mucosal immunity contains a unique immune cell milieu that selectively identify pathogens and limits the transmission and progression of mucosal diseases, such as allergic dermatitis and inflammatory bowel disease (IBD). It also offers protection from localized infection at the site of entry, enables the clearance of pathogens on mucosal surfaces, and leads to the induction of long-term immunity with the ability to shape regulatory responses. Regulatory T (Treg) cells have been a promising strategy to suppress mucosal diseases. To find advances in mucosal treatment, we investigated the therapeutic effects of intranasal pep27 mutant immunization. Nasal immunization protects mucosal surfaces, but nasal antigen presentation appears to entail the need for an adjuvant to stimulate immunogenicity. Here, a novel method is developed to induce Tregs via intranasal immunization without an adjuvant to potentially overcome allergic diseases and gut and lung inflammation using lung-gut axis communication in animal models. The implementation of the pep27 mutant for these therapies should be preceded by studies on Treg resilience through clinical translational studies on dietary changes.

Disruption of intestinal oxygen balance in acute colitis alters the gut microbiome

ABSTRACT The juxtaposition of well-oxygenated intestinal colonic tissue with an anerobic luminal environment supports a fundamentally important relationship that is altered in the setting of intestinal injury, a process likely to be relevant to diseases such as inflammatory bowel disease. Herein, using two-color phosphorometry to non-invasively quantify both intestinal tissue and luminal oxygenation in real time, we show that intestinal injury induced by DSS colitis reduces intestinal tissue oxygenation in a spatially defined manner and increases the flux of oxygen from the tissue into the gut lumen. By characterizing the composition of the microbiome in both DSS colitis-affected gut and in a bioreactor containing a stable human fecal community exposed to microaerobic conditions, we provide evidence that the increased flux of oxygen into the gut lumen augments glycan degrading bacterial taxa rich in glycoside hydrolases which are known to inhabit gut mucosal surface. Continued disruption of the intestinal mucus barrier through such a mechanism may play a role in the perpetuation of the intestinal inflammatory process.