Bacteriotherapy with Streptococcus salivarius 24SMB and Streptococcus oralis 89a oral spray for children with recurrent streptococcal pharyngotonsillitis: a randomized placebo-controlled clinical study

Inhibition of pneumococcal growth and biofilm formation by human isolates of Streptococcus mitis and Streptococcus oralis

In a world facing the unprecedented threat of antibiotic-resistant bacteria, targeted approaches to control colonization and prevent disease caused by common pathobionts offer a promising solution. Streptococcus pneumoniae (pneumococcus) is a leading cause of infections worldwide, affecting both children and adults despite available antimicrobials and vaccines. Colonization, which occurs in the form of a biofilm in the upper respiratory tract, is frequent and a prerequisite for disease and transmission. The use of live bacterial strains as biotherapeutics for infectious diseases is actively being explored. Here, we investigated the potential of commensal streptococci to control S. pneumoniae. Screening of over 300 human isolates led to the identification of seven strains (one Streptococcus oralis and six Streptococcus mitis, designated A22 to G22) with inhibitory activity against S. pneumoniae of multiple serotypes and genotypes. Characterization of A22 to G22 cell-free supernatants indicated the involvement of secreted proteins or peptides in the inhibitory effect of all S. mitis isolates. Genome analyses revealed the presence of 64 bacteriocin loci, encoding 70 putative bacteriocins, several of which are novel and absent or rare in over 7,000 publicly available pneumococcal genomes. Deletion mutants indicated that bacteriocins partially or completely explained the anti-pneumococcal activity of the commensal strains. Importantly, strains A22 to G22 were further able to prevent and disrupt pneumococcal biofilms, a proxy for nasopharyngeal colonization. These results highlight the intricacy of the interactions among nasopharyngeal colonizers and support the potential of strains A22 to G22 to be used as live biotherapeutics, alone or in combination, to control S. pneumoniae colonization.

IMPORTANCE

Streptococcus pneumoniae (pneumococcus) infections remain a major public health issue despite the use of vaccines and antibiotics. Pneumococci asymptomatically colonize the human upper respiratory tract, a niche shared with several commensal Streptococcus species. Competition for space and nutrients among species sharing the same niche is well documented and tends to be more intense among closely related species. Based on this rationale, a screening of several commensal streptococci isolated from the human upper respiratory tract led to the identification of strains of Streptococcus mitis and Streptococcus oralis capable of inhibiting most pneumococcal strains, across diverse serotypes and genotypes. This inhibition was partially or wholly linked to the expression of novel bacteriocins. The selected S. mitis and S. oralis strains significantly disrupted pneumococcal biofilms, indicating a potential for using commensals as biotherapeutics to control pneumococcal colonization, a key step in preventing disease and transmission.

Advancements related to probiotics for preventing and treating recurrent respiratory tract infections in children

Recurrent respiratory tract infections (RRTIs) are a common condition in pediatrics and significantly impact children's quality of life; however, their pathogenesis and contributing factors are not yet fully elucidated. Probiotics have recently emerged as promising agents for modulating intestinal microecology and have gained considerable attention in clinical research on preventing and treating RRTIs in children. This article provides an initial overview of the concept, classification, and mechanisms underlying probiotics. It emphasizes their beneficial effects on respiratory health by modulating intestinal microbial equilibrium, augmenting immune system functionality, and attenuating inflammatory responses. Subsequently, we examine existing research regarding the use of probiotics in pediatric RRTIs. Numerous clinical trials have unequivocally demonstrated that supplementing with probiotics can significantly reduce both the frequency and severity of RRTIs in children while also simultaneously decreasing antibiotic usage. However, there are ongoing controversies and challenges in current research concerning the influence of probiotic type, dosage, duration of use, and other factors on efficacy. Furthermore, variations have been observed across different studies. Additionally, it is crucial to further evaluate the safety and potential long-term side effects associated with probiotic use in children with RRTIs. In conclusion, we propose future research directions including conducting more high-quality randomized controlled trials to optimize application strategies for probiotics alongside other treatments while considering variations based on age and health conditions among pediatric populations. Finally, in summary although probiotics exhibit promising benefits in preventing and treating RRTIs in children; additional studies are necessary to refine their application strategies ensuring both safety and effectiveness.

Changes in the pharyngeal and nasal microbiota in pediatric patients with adenotonsillar hypertrophy

The present study aimed to investigate the pharyngeal and nasal microbiota composition in children with adenotonsillar hypertrophy (AH) and assess longitudinal alterations in both microbiota after a probiotic oral spray treatment. A cohort of 57 AH patients were enrolled and randomly assigned to the probiotic and placebo groups for a 5-month treatment course. Pharyngeal and nasal swabs were collected before and after treatment and analyzed by 16S rRNA-based metataxonomics and axenic cultures for pathobiont identification. 16S rRNA sequences from pharyngeal and nasal swabs of 65 healthy children (HC) were used as microbiota reference profiles. We found that the pharyngeal and nasal microbiota of AH children were similar. When compared to HC, we observed an increase of the genera Rothia, Granulicatella, Streptococcus, Neisseria, and Haemophilus, as well as a reduction of Corynebacterium, Pseudomonas, Acinetobacter, and Moraxella in both microbiota of AH patients. After probiotic treatment, we confirmed the absence of adverse effects and a reduction of upper respiratory tract infections (URTI). Moreover, the composition of pharyngeal microbiota was positively influenced by the reduction of potential pathobionts, like Haemophilus spp., with an increase of beneficial microbial metabolic pathways. Finally, the probiotic reduced the abundance of the pathobionts Streptococcus mitis and Gemella haemolysans in relation to AH severity. In conclusion, our results highlight the alterations of the pharyngeal and nasal microbiota associated with AH. Moreover, probiotic administration conferred protection against URTI and reduced the presence of potential pathobionts in patients with AH.

IMPORTANCE

Adenotonsillar hypertrophy (AH) is considered the main cause of breathing disorders during sleep in children. AH patients, after significant morbidity and often multiple courses of antibiotics, often proceed to tonsillectomy and/or adenoidectomy. Given the potential risks associated with these procedures, there is a growing interest in the use of nonsurgical adjuvant therapies, such as probiotics, that could potentially reduce their need for surgical intervention. In this study, we investigated the pharyngeal and nasal microbiota in patients with AH compared with healthy children. Furthermore, we tested the effects of probiotic spray administration on both disease symptoms and microbiota profiles, to evaluate the possible use of this microbial therapy as an adjuvant for AH patients.

Anti-caries Streptococcus spp.: A potential preventive tool for special needs patients

INTRODUCTION

Probiotics are living microorganisms that act on the host-microbiome interface to restore the microbiota's physiological homeostasis. Numerous probiotics have been marketed with inhibitory activity against Streptococcus mutans and consequently with a potential anti-caries effect, mainly of the genera Lactobacillus and Bifidobacterium, whose main disadvantage is their limited ability to settle in the oral cavity.

METHODS

This narrative review describes the main Streptococcus spp. with probiotic anti-Streptococcus mutans activity, whose substantivity is greater than that of Lactobacillus spp. and consequently with anti-caries potentiality. We performed a literature review in the PubMed, Science Direct and Google Scholar databases of articles published in English (without time restriction) related to caries and probiotics.

RESULTS

The potential identified anti-caries probiotics included Streptococcus spp. A12, Streptococcus oralis (AJ3), Streptococcus oligofermentans, Streptococcus salivarius (K12, M18, JH, LAB813, 24SMB), Streptococcus spp. with arginolytic activity (S. sanguinis, S. gordonii, S. ratti, S. parasanguinis, S. intermedius, S. australis, and S. cristatus), Streptococcus rattus (JH145), Streptococcus dentisani and Streptococcus downii.

CONCLUSIONS

The possibility of using these Streptococcus spp. as probiotics that inhibit the growth of dental plaque and the development of carious lesions represents a potential tool of particular interest for individuals with physical or intellectual disabilities that impede the routine and effective application of mechanical dental plaque removal techniques.

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.

A Brief Review of Local Bacteriotherapy for Preventing Respiratory Infections

Recurrent respiratory infections (RRIs) account for relevant economic and social implications and significantly affect family life. Local Bacteriotherapy (LB) represents an innovative option in preventing RRIs. Local bacteriotherapy consists of administering “good” and safe bacteria (probiotics) by nasal or oral route. In particular, two strains (Streptococcus salivarius 24SMB and Streptococcus oralis 89a) are commonly used. The present article presents and discusses the literature concerning LB. Infections of airways include the upper and lower respiratory tract. A series of clinical trials investigated the preventive role of LB in preventing upper and lower RIs. These studies demonstrated that LB safely reduced the prevalence and severity of RIs, the use of antibiotics, and absences from school. Therefore, Local Bacteriotherapy may be considered an interesting therapeutic option in RRI prevention.

Streptococcus salivarius 24SMBc Genome Analysis Reveals New Biosynthetic Gene Clusters Involved in Antimicrobial Effects on Streptococcus pneumoniae and Streptococcus pyogenes

Streptococcus salivarius 24SMBc is an oral probiotic with antimicrobial activity against the otopathogens Streptococcus pyogenes and Streptococcus pneumoniae. Clinical studies have reinforced its role in reducing the recurrence of upper respiratory tract infections (URTIs) and rebalancing the nasal microbiota. In this study, for the first time, we characterized 24SMBc by whole genome sequencing and annotation; likewise, its antagonistic activity vs. Streptococcus pneumoniae and Streptococcus pyogenes was evaluated by in vitro co-aggregation and competitive adherence tests. The genome of 24SMBc comprises 2,131,204 bps with 1933 coding sequences (CDS), 44 tRNA, and six rRNA genes and it is categorized in 319 metabolic subsystems. Genome mining by BAGEL and antiSMASH tools predicted three novel biosynthetic gene clusters (BGCs): (i) a Blp class-IIc bacteriocin biosynthetic cluster, identifying two bacteriocins blpU and blpK; (ii) an ABC-type bacteriocin transporter; and (iii) a Type 3PKS (Polyketide synthase) involved in the mevalonate pathway for the isoprenoid biosynthetic process. Further analyses detected two additional genes for class-IIb bacteriocins and 24 putative adhesins and aggregation factors. Finally, in vitro assays of 24SMBc showed significant anti-adhesion and co-aggregation effects against Streptococcus pneumoniae strains, whereas it did not act as strongly against Streptococcus pyogenes. In conclusion, we identified a novel blpU-K bacteriocin-encoding BGC and two class-IIb bacteriocins involved in the activity against Streptococcus pneumoniae and Streptococcus pyogenes; likewise the type 3PKS pathway could have beneficial effects for the host including antimicrobial activity. Furthermore, the presence of adhesins and aggregation factors might be involved in the marked in vitro activity of co-aggregation with pathogens and competitive adherence, showing an additional antibacterial activity not solely related to metabolite production. These findings corroborate the antimicrobial activity of 24SMBc, especially against Streptococcus pneumoniae belonging to different serotypes, and further consolidate the use of this strain in URTIs in clinical settings.

Probiotics for Otolaryngologic Disorders

Chronic low-level inflammation is a causative factor in many of our common diseases. Switching to an anti-inflammatory diet is an important step that patients can take in for rectifying this risk factor. In this review, the author discusses the essential components of an anti-inflammatory diet and its contribution not only to the overall well-being but also to the body's defense against disease. The human microbiome is reviewed in detail and dietary connections and recommendations are explained for several otolaryngologic conditions.

Engineered endosymbionts that alter mammalian cell surface marker, cytokine and chemokine expression

Developing modular tools that direct mammalian cell function and activity through controlled delivery of essential regulators would improve methods of guiding tissue regeneration, enhancing cellular-based therapeutics and modulating immune responses. To address this challenge, Bacillus subtilis was developed as a chassis organism for engineered endosymbionts (EES) that escape phagosome destruction, reside in the cytoplasm of mammalian cells, and secrete proteins that are transported to the nucleus to impact host cell response and function. Two synthetic operons encoding either the mammalian transcription factors Stat-1 and Klf6 or Klf4 and Gata-3 were recombined into the genome of B. subtilis expressing listeriolysin O (LLO) from Listeria monocytogenes and expressed from regulated promoters. Controlled expression of the mammalian proteins from B. subtilis LLO in the cytoplasm of J774A.1 macrophage/monocyte cells altered surface marker, cytokine and chemokine expression. Modulation of host cell fates displayed some expected patterns towards anti- or pro-inflammatory phenotypes by each of the distinct transcription factor pairs with further demonstration of complex regulation caused by a combination of the EES interaction and transcription factors. Expressing mammalian transcription factors from engineered intracellular B. subtilis as engineered endosymbionts comprises a new tool for directing host cell gene expression for therapeutic and research purposes.

The establishment of non-pathogenic engineered endosymbionts through B. subtilis is presented, with the aim of delivering mammalian transcription factors to the host cell for therapeutics and research.

Probiotics for preventing acute upper respiratory tract infections

BACKGROUND

Probiotics are live micro-organisms that may give a beneficial physiological effect when administered in adequate amounts. Some trials show that probiotic strains can prevent respiratory infections. Even though our previously published review showed the benefits of probiotics for acute upper respiratory tract infections (URTIs), several new studies have been published. This is an update of a review first published in 2011 and updated in 2015.

OBJECTIVES

To assess the effectiveness and safety of probiotics (any specified strain or dose), compared with placebo or no treatment, in the prevention of acute URTIs in people of all ages, at risk of acute URTIs.

SEARCH METHODS

We searched CENTRAL (2022, Issue 6), MEDLINE (1950 to May week 2, 2022), Embase (1974 to 10 May 2022), Web of Science (1900 to 10 May 2022), the Chinese Biomedical Literature Database, which includes the China Biological Medicine Database (from 1978 to 10 May 2022), the Chinese Medicine Popular Science Literature Database (from 2000 to 10 May 2022), and the Master's Degree Dissertation of Beijing Union Medical College Database (from 1981 to 10 May 2022). We searched the World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov for completed and ongoing trials on 10 May 2022.

SELECTION CRITERIA

We included individual randomised controlled trials (RCTs) and cluster-RCTs comparing probiotics with placebo or no treatment to prevent acute URTIs. The participants were children, adults, or the elderly in the community, care facilities, schools, or hospitals. Our main outcomes were the number of participants diagnosed with URTIs (at least one event and at least three events), the incidence rate (number of cases/person year) of acute URTIs, and the mean duration of an episode of URTIs. Our secondary outcomes were the number of participants who were absent from childcare centre, school, or work due to acute URTIs; the number of participants who used prescribed antibiotics for acute URTIs; and the number of participants who experienced at least one adverse event from probiotics. We excluded studies if they did not specify acute respiratory infections as 'upper'; studies with more than 50% of participants vaccinated against influenza or other acute URTIs within the last 12 months; and studies with significantly different proportions of vaccinated participants between the probiotics arm and the placebo or no treatment arm.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the eligibility of trials and extracted data using standard Cochrane methodological procedures. We analysed both intention-to-treat and per-protocol data and used a random-effects model. We expressed results as risk ratios (RRs) for dichotomous outcomes and mean differences (MDs) for continuous outcomes, both with 95% confidence intervals (CIs). We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We included 23 individual RCTs and one cluster-RCT. As one of the individual RCTs did not report outcomes in a usable way, we could only meta-analyse data from 23 trials, involving a total of 6950 participants including children (aged from one month to 11 years old), adults (mean age 37.3), and older people (mean age 84.6 years). One trial reported 22.5% flu-vaccine participants within the last 12 months, and 25.4% flu-vaccine participants during the intervention. Probiotics were more likely to be given with milk-based food in children; administered in powder form in adults; and given with milk-based food or in capsules in the elderly. Most of the studies used one or two strains (e.g. Lactobacillus plantarum HEAL9, Lactobacillus paracasei (8700:2 or N1115)) and 109 or 1011 colony-forming units (CFU)/day of probiotics for more than three months. We found that probiotics may reduce the number of participants diagnosed with URTIs (at least one event) (RR 0.76, 95% CI 0.67 to 0.87; P < 0.001; 16 studies, 4798 participants; low-certainty evidence); likely reduce the number of participants diagnosed with URTIs (at least three events) (RR 0.59, 95% CI 0.38 to 0.91; P = 0.02; 4 studies, 763 participants; moderate-certainty evidence); may reduce the incidence rate (number of cases/person year) of URTIs (rate ratio 0.82, 95% CI 0.73 to 0.92, P = 0.001; 12 studies, 4364 participants; low-certainty evidence); may reduce the mean duration of an episode of acute URTIs (MD -1.22 days, 95% CI -2.12 to -0.33; P = 0.007; 6 studies, 2406 participants; low-certainty evidence); likely reduce the number of participants who used prescribed antibiotics for acute URTIs (RR 0.58, 95% CI 0.42 to 0.81; P = 0.001; 6 studies, 1548 participants; moderate-certainty evidence); and may not increase the number of participants who experienced at least one adverse event (RR 1.02, 95% CI 0.90 to 1.15; P = 0.79; 8 studies, 2456 participants; low-certainty evidence). Evidence showing a decrease in the number of people absent from childcare centre, school, or work due to acute URTIs with probiotics is very uncertain (RR 0.14, 95% CI 0.03 to 0.59; 1 study, 80 participants; very low-certainty evidence). Adverse events from probiotics were minor, and most commonly gastrointestinal symptoms, such as vomiting, flatulence, diarrhoea, and bowel pain.  AUTHORS' CONCLUSIONS: Overall, we found that probiotics were better than placebo or no treatment in preventing acute URTIs.

The Role of Probiotics in Chronic Rhinosinusitis Treatment: An Update of the Current Literature

Chronic rhinosinusitis (CRS) is a significant health problem. It affects 5–12% of the general population. The causes that underlie the onset of CRS are not yet well known. However, many factors may contribute to its onset, such as environmental factors and the host’s general condition. Medical treatment mainly uses local corticosteroids, nasal irrigation, and antibiotics. In recent years, a new therapeutic approach that employs the use of probiotics emerged. Probiotics have been extensively studied as a therapy for dysbiosis and inflammatory pathologies of various parts of the body. We aimed to examine the studies in vivo and in vitro and clinicals reports in the existing literature to update probiotics’ role in rhinosinusitis chronic medical treatment.

Review of probiotic use in otolaryngology

OBJECTIVE

Probiotics have garnered considerable attention as an intervention for various conditions common to otolaryngology. The purpose of this review is to evaluate the current literature to offer recommendations about the safety and efficacy of probiotic management in otolaryngologic conditions.

STUDY DESIGN

Narrative review.

METHODS

PubMed and Google Scholar were queried using pertinent keywords to retrieve relevant studies with particular focus in the recent 5 years. All abstracts were assessed and studies, reviews and meta-analyses achieving evaluation of probiotic therapies or characterization of microbiome changes were included for further review. Studies were categorized by condition or anatomic region across various subspecialties. Key data parameters were extracted and evaluated across studies and treatment types.

RESULTS

Strong evidence exists for the use probiotic agents to improve symptoms for allergic rhinitis, chronic rhinosinusitis and certain dental conditions. Despite promising results, further investigation is needed to evaluate and optimize probiotic delivery for mitigating otitis media, oropharyngeal inflammation and upper respiratory tract infections. Preclinical studies suggest that probiotics may potentially offer benefit for voice prosthesis maintenance, wound healing and mitigation of oral dysplasia.

CONCLUSION

Probiotic therapies may offer clinical benefit in a variety of contexts within the field of otolaryngology, especially for short-term relief of certain inflammatory conditions of the oral cavity, auditory and nasal cavities. Further investigation is warranted for evaluation of long-term outcomes and pathogenic deterrence.

Local Bacteriotherapy - a promising preventive tool in recurrent respiratory infections

INTRODUCTION

Children with recurrent respiratory infections (RRI) represent a social issue for the economic burden and the negative family impact. Local Bacteriotherapy is an attractive therapeutic strategy that could be potentially effective in preventing infections. The current article remarks on the existing evidence of preventing RRI by Local Bacteriotherapy.

AREAS COVERED

The literature search methodology was based on the articles cited by PubMed from 1980 to 2020. Respiratory infections include rhino-pharyngitis, otitis media, rhinosinusitis, pharyngo-tracheitis, bronchitis, and pneumonia. Several studies were performed to investigate the effects of Local Bacteriotherapy in children with RRI. Both intranasal and oral Local Bacteriotherapy were evaluated. The findings showed that Local Bacteriotherapy significantly reduced the number of RI episodes, their severity, the use of antibiotics, and school absences.

EXPERT OPINION

Local Bacteriotherapy is a promising approach to RRI prevention and could be a profitable strategy to contrast infections in the future.

Commensal bacteria in the upper respiratory tract regulate susceptibility to infection

The human body is host to several distinct microbial communities. Disruption of these communities increases susceptibility to a wide range of diseases, including respiratory tract infections. While commensal bacteria in the gut contribute to this effect, recent studies point to a role for commensals occupying the upper respiratory tract through direct pathogen killing and by modifying nasal and lung immune homeostasis. Clinical trials exploring 'probiotic' respiratory tract commensals are an exciting development in this area. Upper respiratory tract microbiome sequencing has revealed that destabilization of this community precedes infection, indicating that microbiome profiling of individuals has predictive value. Further investigation of respiratory tract commensal-host interactions will be critical to translate bacterial-mediated protection toward new therapeutic approaches for respiratory tract disease.

Analysis of microbial changes in the tonsillar formalin-fixed paraffin-embedded tissue of Chinese patients with IgA nephropathy

BACKGROUND

Immunoglobulin A nephropathy (IgAN) is a prevalent chronic glomerular disease contribution to end-stage renal failure (ESRD). The tonsillar microbiota is closely associated with IgAN diseases based on the mucosal immune response. However, the composition and function of in tonsillar microbiota in participant patients with IgAN remains unknown. In this study, we detected the tonsillar microbiota changes of IgAN patients in Heilongjiang province located in northeast China.

MATERIAL AND METHODS

We collected from 21 patients with IgAN and 16 patients with chronic tonsillitis (CT) who had undergone tonsillectomy previously. Histological review of all samples from formalin-fixed paraffin-embedded (FFPE) tissue were performed. Extracted DNA from FFPE tissue blocks, after that V4 regions of 16S ribosomal RNA (rRNA) sequencing and comparative analyses of tonsillar flora between two groups were performed. The statistical analysis used the SPSS version of 21.

RESULTS

Visualization of microorganisms by Gram and Warthin-Starry (WS) silver stains, preliminarily observed the morphological characteristics of microbiome in FFPE tissue cases, such as bacteria or fungi. Tonsillar FFPE samples from the IgAN patients and CT controls showed significant differences in tonsillar microbial certain compositions and functions. We found that there were eight dominant genera that can be available to distinguish IgAN patients from CT controls. Compared with CT controls, at genus level, the relative abundances of Methylocaldum and unclassified_f_Prevotellaceae were significantly higher, while the abundances of Anaerosphaera, Halomonas, Trichococcus, Peptostreptococcus, norank_f_Synergistaceae and unclassified_k_norank_d_Bacteria were significantly lower in IgAN patients. Principal co-ordinates analysis (PCOA) distinguished IgAN patients from CT controls, and receiver operating characteristic (ROC) curves analysis confirmed that the diagnosis of disease has certain diagnostic significance. In addition, Functional analysis revealed that partly Enzymes and KOs were increased in the IgAN patients.

CONCLUSIONS

Histological screening results were very helpful for further gene sequencing, not only to supplement the observation of bacterial morphology and structure, but also to prepare for subsequent gene sequencing and bioinformatics analysis. We elucidated subtle relevance between changes in tonsillar microbiota and IgAN patients, which can be utilized to predict the incidence of IgAN disease. In addition, we predicted that some enzymes, and KOs were closely related to IgAN.

In Vitro Effects of Streptococcus oralis Biofilm on Peri-Implant Soft Tissue Cells

Human gingival epithelial cells (HGEps) and fibroblasts (HGFs) are the main cell types in peri-implant soft tissue. HGEps are constantly exposed to bacteria, but HGFs are protected by connective tissue as long as the mucosa-implant seal is intact. Streptococcus oralis is one of the commensal bacteria, is highly abundant at healthy implant sites, and might modulate soft tissue cells-as has been described for other streptococci. We have therefore investigated the effects of the S. oralis biofilm on HGEps and HGFs. HGEps or HGFs were grown separately on titanium disks and responded to challenge with S. oralis biofilm. HGFs were severely damaged after 4 h, exhibiting transcriptional inflammatory and stress responses. In contrast, challenge with S. oralis only induced a mild transcriptional inflammatory response in HGEps, without cellular damage. HGFs were more susceptible to the S. oralis biofilm than HGEps. The pro-inflammatory interleukin 6 (IL-6) was attenuated in HGFs, as was interleukin 8 (CXCL8) in HGEps. This indicates that S. oralis can actively protect tissue. In conclusion, commensal biofilms can promote homeostatic tissue protection, but only if the implant-mucosa interface is intact and HGFs are not directly exposed.

Evolution of Lantibiotic Salivaricins: New Weapons to Fight Infectious Diseases

Lantibiotic salivaricins are polycyclic peptides containing lanthionine and/or β-methyllanthionine residues produced by certain strains of Streptococcus salivarius, which almost exclusively reside in the human oral cavity. The importance of these molecules stems from their antimicrobial activity towards relevant oral pathogens which has so far been applied through the development of salivaricin-producing probiotic strains. However, salivaricins may also prove to be of great value in the development of new and novel antibacterial therapies in this era of emerging antibiotic resistance. In this review, we describe the biosynthesis, antimicrobial activity, structure, and mode of action of the lantibiotic salivaricins characterized to date. Moreover, we also provide an expert opinion and suggestions for future development of this important field of microbiology.

Bacteriotherapy with Streptococcus salivarius 24SMB and Streptococcus oralis 89a nasal spray for treatment of upper respiratory tract infections in children: a pilot study on short-term efficacy

BACKGROUND

Recurrent respiratory infections (RRIs) are defined by the presence of at least one of the following criteria: (i) > 6 annual respiratory infections (RIs); (ii) > 1 monthly RIs involving the upper airways from September to April; (iii) > 3 annual RIs involving the lower airways represent a very common health problem in the first years of life. We conducted a multi-centre, prospective, single-open study to assess the efficacy and the safety of Streptococcus salivarius 24SMBc and Streptococcus oralis 89a in the prevention of upper respiratory tract infections (URTIs) in children.

METHODS

Ninety-one children (M:F = 47:44, mean age 7.4 ± 2.3 years) with RRIs were enrolled in the study between September and November 2018. At baseline, children received Streptococcus salivarius 24SMBc and Streptococcus oralis 89a as 2 puffs for nostril twice/day for 7 days/months. The treatment lasted for 3 consecutive months. Efficacy was expressed in terms of absence or presence of fever, cough, bronchospasm, rhinorrhea and otalgia, at 1 month (T1), and 3 (T3) months. Safety and tolerability of the probiotic were evaluated on the basis of the number and type of adverse events (AEs) recorded during the treatment.

RESULTS

Children treated with Streptococcus salivarius 24SMBc and Streptococcus oralis 89a showed a significant decrease of symptoms including episodes of fever, cough, bronchospasm, rhinorrhea, and otalgia (p < 0.001) compared to baseline. The treatment significantly reduced the number of episodes of fever, cough, bronchospasm, rhinorrhea, otalgia, and cough also in patients with positive familial history for atopy and in atopic children (p < 0.05). No significant differences in symptoms among children with negative familial history for atopy and children with positive familial history for atopy subgroups, not atopic and atopic children subgroups, and smoke-exposed and not smoke-exposed subgroups were observed (p > 0.05). Conducting a subgroup analysis according to the age, it has been reported that children aged 1-3 years old showed an improvement in all symptoms, however, they become statistically significant only at the end of the 3 months of treatment (p < 0.05). Conversely, in children aged 3-6 and 6-12 years old, the therapeutic efficacy was progressive and significant already from the first month of therapy (p < 0.05). None of the children were withdrawn from the study because of AEs, although 9 children experienced burning nose leading to interruption of therapy.

CONCLUSIONS

Our findings suggest that Streptococcus salivarius 24SMBc and Streptococcus oralis 89a treatment is safe and seems to be effective on short-term in the treatment of RRIs. Studies involving a longer observation period are necessary to establish the real efficacy of the product for the treatment of pediatric patients affected by RRIs.

Oral bacteriotherapy in children with recurrent respiratory infections: a real-life study

Children with recurrent respiratory infections (RRI) represent a social issue for the economic burden and the familiar negative impact. Bacteriotherapy, such as the administration of "good" bacteria, is a new therapeutic strategy that could be potentially effective in preventing infections. The current study tested the hypothesis of preventing RRI by oral Bacteriotherapy in a real-life setting. This open study was conducted in an outpatient clinic, enrolling 51 children (27 males, mean age 4.8 ± 2.6 years) suffering from RRI. Children were treated with an oral spray, containing Streptococcus salivarius 24SMB and Streptococcus oralis89a (125 x 109 CFU/g), 2 puffs per os once/day for 30 consecutive days; this course was repeated for 3 months. The evaluated parameters were: RI number and school absences reported in the current year; these outcomes were compared with those recorded in the past year. The mean number of RI significantly diminished: from 5.17 (2.30) in the past year to 2.25 (2.43) after the treatment (p<0.0001). The mean number of school absences significantly diminished (from 3.35 to 1.86; p<0.0001). In conclusion, this real-life study suggests that oral Bacteriotherapy with Streptococcus salivarius 24SMB and Streptococcus oralis89a could efficaciously and safely prevent RRI in children.

Inflammation, infection, and allergy of upper airways: new insights from national and real-world studies

The upper airways (UA) should be considered as a functional unit. Current functional anatomy divides URT in three, mutually dependent, "junction boxes": i) the ostio-meatal complex (OMC), ii) the spheno-ethmoidal recess (SER), and iii) the rhinopharynx (RP). Correct ventilation and effective mucociliary clearance of these sites significantly affect the healthy physiology of the entire respiratory system. The OMC, SER, and RP obstruction is the first pathogenic step in the inflammatory/infectious cascade of UA disorders. The inflammation of the respiratory mucosa is the main pathogenic factor for airway obstruction. Moreover, bacterial biofilm (a strategy modality of bacterial survival) is an important local cause of systemic antibiotic ineffectiveness, recurrent infections, and antibiotic resistance. Health microbiota guarantees UA wellness; on the contrary, dysbiosis promotes and worsens UA infections. Allergy, namely type 2 inflammation, is a common cause of UA obstruction such as promoting in turn infections. Fiberoptic endoscopy is a mandatory diagnostic tool in clinical practice. Nasal cytology, mainly concerning flow cytometry, allows defining rhinitis phenotypes so allowing a precision medicine approach. Several conventional therapeutic approaches are available, but efficacy and safety should be ever properly considered before the prescription. Also, complementary medicine plays a fruitful role in the management of UA diseases. National and real-world studies are reported and discussed as they may be useful in daily clinical practice.