News Feature: Cleaning up the hygiene hypothesis. Proc Natl Acad Sci U S A. 2017;114:1433-1436. [PMID: 28196925 DOI: 10.1073/pnas.1700688114]

Childhood asthma and mould in homes-A meta-analysis

Asthma is a multifaceted and multicausal disease. Childhood asthma is strongly influenced by genetic traits and is characterized by hyperreactivity of the airways so that also unspecific triggers including moulds can trigger an asthma attack. Therefore, it is undisputed that moulds in the home can cause asthma attacks in asthmatic children. It is, however, unclear if mould in homes also induce the development of asthma. Because more and more severe attacks in asthmatic children living in mouldy homes might speed up the diagnosis of asthma, cross-sectional studies are not well-suited to differentiate between mould as a causative or only as a precipitating factor. Cross-sectional studies show an increased asthma risk and poorer lung function in children living in mouldy homes. To better understand the causal role of mould in homes, a systematic review was performed with random effects meta-analysis focusing on cohort and case-control studies only.We found 21 case-control and 11 cohort studies examining the association between mould at home and later advent of childhood asthma. According to the case-control studies, mouldy homes increase the risk of asthma by 53% (95 confidence interval [CI]: 42-65%) with no evidence of heterogeneity or publication bias. Risk estimates based on cohort studies were smaller with 15% (1-31%). The cohort studies also showed no publication bias but substantial heterogeneity (I2 = 60.5, p = 0.005). Heterogeneity could be partly explained by percentage of male children, age of participants, and publication year, but was not affected by study quality.In conclusion, living in mouldy homes during childhood seems to increase the risk of later developing bronchial asthma.

Human in vivo assessment of the survival and germination of Heyndrickxia coagulans SNZ1969 spores delivered via gummy candies

Confectionary products hold promise as unconventional food carriers for probiotic microorganisms. This study explored the delivery of Heyndrickxia coagulans SNZ1969, a spore-forming probiotic, using gummy candies. In this study, we prepared gummy candies containing bacterial spores with a viable count that remained stable during a 24-month shelf-life period, meeting the label claim of at least one billion CFUs per serving (24 g). Then, we carried out an intervention trial involving 24 healthy adults who consumed one serving per day for two weeks followed by an additional two weeks of follow-up. Fecal samples were collected and analyzed with a protocol that allowed the viable counts of SNZ1969, both in spore and vegetative forms. The obtained results revealed that bacterial spores germinated in all volunteers. SNZ1969 persistence in the gut was monitored for two weeks after the end of gummy candy consumption, indicating its potential for prolonged colonization. These findings highlight the potential of unconventional food carriers for probiotic delivery and suggest that spore-forming probiotics can be metabolically active in the human intestine. These findings provide information for the development of food products containing spore-forming probiotics and their potential benefits in promoting gastrointestinal health.

Greenspaces And Cardiovascular Health

Accumulating evidence suggests that living in areas of high surrounding greenness or even brief exposures to areas of high greenery is conducive to cardiovascular health, which may be related to the environmental, social, psychological, and physiological benefits of greenspaces. Recent data from multiple cross-sectional, longitudinal, and cohort studies suggest that living in areas of high surrounding greenness is associated with a lower risk of all-cause and cardiovascular mortality. High levels of neighborhood greenery have been linked also to a decrease in the burden of cardiovascular disease risk factors as reflected by lower rates of hypertension, dyslipidemia, and diabetes. Those who live in greener environments report better mental health and more frequent social interactions, which can benefit cardiovascular health as well. In this narrative review, we discuss evidence linking greenspaces to cardiovascular health as well as the potential mechanisms underlying the beneficial effects of greenspaces, including the impact of vegetation on air, noise and light pollution, ambient temperature, physical activity, mental health, and biodiversity. We review literature on the beneficial effects of acute and chronic exposure to nature on cardiovascular disease risk factors, inflammation and immune function, and we highlight the potential cardiovascular effects of biogenic volatile organic compounds that are emitted by trees and shrubs. We identify current knowledge gaps in this area and underscore the need for additional population studies to understand more clearly and precisely the link between greenness and health. Such understanding is urgently needed to fully redeem the promise of greenspaces in preventing adverse environmental exposures, mitigating the effects of climate change, and creating healthier living environments.

Lactic acid bacteria naturally associated with ready-to-eat rocket salad can survive the human gastrointestinal transit

It was theorized that modernization and the decline in harmless microbial populations associated with food have altered the gut microbiota, impacting host metabolism and immunity. Western dietary patterns, characterized by processed foods and preservation methods, may significantly reduce the microbial population associated with food. To mitigate the consequences of bacterial deprivation, the integration of these diets with fermented foods is commonly proposed. Nonetheless, non-fermented food consumed raw may also be an important source of viable microbial cells for the human microbiome. This study investigates whether salad-associated LAB can survive the gastrointestinal transit (GIT) and contribute to the gut microbiota. LAB strains were quantified and isolated from rocket salad (Eruca vesicaria subsp. sativa), and their survival through GIT was assessed via intervention trials in healthy adults and in vitro. Moreover, bacterial communities in fecal samples were analyzed after three days of rocket salad consumption. Washing with a sodium hypochlorite solution drastically reduced total bacterial load and eliminated viable LAB. The quantity of LAB introduced through salads did not significantly alter the gut microbiota composition. Rocket salads harbored Weissella and Leuconostoc species. A significant increase in Weissella spp. but not in Leuconostoc spp. was observed after the consumption of rocket salad. Simulated GIT experiments suggested that the food matrix and the initial number of ingested viable bacteria may have been important in determining survival. These findings propose that plant products could serve as sources of live LAB for the human gut. Further research with diverse vegetables and longer interventions is needed, encouraging studies on raw, non-fermented foods and their impact on the human intestinal microbiome.

Airways Type-2 Related Disorders: Multiorgan, Systemic or Syndemic Disease?

Chronic rhinosinusitis (CRS) has recently undergone a significant paradigm shift, moving from a phenotypical classification towards an "endotype-based" definition that places more emphasis on clinical and therapeutic aspects. Similar to other airway diseases, like asthma, most cases of CRS in developed countries exhibit a dysregulated type-2 immune response and related cytokines. Consequently, the traditional distinction between upper and lower airways has been replaced by a "united airway" perspective. Additionally, type-2 related disorders extend beyond respiratory boundaries, encompassing conditions beyond the airways, such as atopic dermatitis. This necessitates a multidisciplinary approach. Moreover, consideration of possible systemic implications is crucial, particularly in relation to sleep-related breathing diseases like Obstructive Sleep Apnoea Syndrome (OSAS) and the alteration of systemic inflammatory mediators such as nitric oxide. The trends in epidemiological, economic, and social burden are progressively increasing worldwide, indicating syndemic characteristics. In light of these insights, this narrative review aims to present the latest evidence on respiratory type-2 related disorders, with a specific focus on CRS while promoting a comprehensive perspective on the "united airways". It also introduces a novel concept: viewing these conditions as a multiorgan, systemic, and syndemic disease.

Early-life microbiota-immune homeostasis

As the prevalence of allergy and autoimmune disease in industrialized societies continues to rise, improving our understanding of the mechanistic roles behind microbiota-immune homeostasis has become critical for informing therapeutic interventions in cases of dysbiosis. Of particular importance, are alterations to intestinal microbiota occurring within the critical neonatal window, during which the immune system is highly vulnerable to environmental exposures. This review will highlight recent literature concerning mechanisms of early-life microbiota-immune homeostasis as well as discuss the potential for therapeutics in restoring dysbiosis in early life.

Bacterial immunotherapy is highly effective in reducing recurrent upper respiratory tract infections in children: a prospective observational study

PURPOSE

Whilst immunotherapy is an appealing option as it could reduce the burden of recurrent pediatric respiratory tract infections (RTI), there is limited evidence on its effectiveness and more research was requested in order to better understand this therapeutic modality.

METHODS

We performed a prospective cohort study involving 57 subjects to assess the safety and effectiveness a 3-month regimen of either typified or patient-specific bacterial lysates could have in reducing the number of RTIs in children aged 0 to 11 years with histories of recurrent episodes.

RESULTS

After a 6-month follow-up, the number of RTIs and school absenteeism dropped sharply and significantly, from an adjusted mean (standard error) of 0.6 (0.04) episodes/month to 0.1 (0.03) episodes/month (74.7% reduction, P < 0.001), and from an adjusted mean score of 4.6 (1.06) points to 0.0 (0.01) points over 10 (99.5% reduction, P < 0.001), respectively. There was also a significant decrease in the severity of symptoms. No adverse reactions were observed.

CONCLUSION

The use of the study product is associated with a decreased risk of recurrent RTIs in children, with a very favorable safety profile that warrants further investigation in randomized clinical trials.

Host-Parasite Coevolution in Primates

Organisms adapt to their environment through evolutionary processes. Environments consist of abiotic factors, but also of other organisms. In many cases, two or more species interact over generations and adapt in a reciprocal way to evolutionary changes in the respective other species. Such coevolutionary processes are found in mutualistic and antagonistic systems, such as predator-prey and host-parasite (including pathogens) relationships. Coevolution often results in an "arms race" between pathogens and hosts and can significantly affect the virulence of pathogens and thus the severity of infectious diseases, a process that we are currently witnessing with SARS-CoV-2. Furthermore, it can lead to co-speciation, resulting in congruent phylogenies of, e.g., the host and parasite. Monkeys and other primates are no exception. They are hosts to a large number of pathogens that have shaped not only the primate immune system but also various ecological and behavioral adaptions. These pathogens can cause severe diseases and most likely also infect multiple primate species, including humans. Here, we briefly review general aspects of the coevolutionary process in its strict sense and highlight the value of cophylogenetic analyses as an indicator for coevolution.

Ready-To-Eat Rocket Salads as Potential Reservoir of Bacteria for the Human Microbiome

Reportedly, Western-type diets may induce the loss of key microbial taxa within the gastrointestinal microbiota, promoting the onset of noncommunicable diseases. It was hypothesized that the consumption of raw vegetables could contribute to the maintenance of the intestinal microbial community structure. In this context, we explored bacteria associated with commercial rocket salads produced through different farming practices: traditional (conventional, organic, and integrated) and vertical farming. Viable counts of mesophilic bacteria and lactic acid bacteria (LAB) were performed on plate count agar (PCA) and de Man-Rogosa-Sharpe (MRS) agar at pH 5.7, whereas metataxonomics through 16S rRNA gene sequencing was used to profile total bacteria associated with rocket salads. We found that rocket salads from vertical farming had much fewer viable bacteria and had a bacterial community structure markedly different from that of rocket salads from traditional farming. Furthermore, although α- and β-diversity analyses did not differentiate rocket samples according to farming techniques, several bacterial taxa distinguished organic and integrated from conventional farming salads, suggesting that farming practices could affect the taxonomic composition of rocket bacterial communities. LAB were isolated from only traditional farming samples and belonged to different species, which were variably distributed among samples and could be partly associated with farming practices. Finally, the INFOGEST protocol for in vitro simulation of gastrointestinal digestion revealed that several taxonomically different rocket-associated bacteria (particularly LAB) could survive gastrointestinal transit. This study suggests that commercial ready-to-eat rocket salads harbor live bacteria that possess the ability to survive gastrointestinal transit, potentially contributing to the taxonomic structure of the human gut microbiota. IMPORTANCE Western-type diets are composed of foods with a reduced amount of naturally occurring microorganisms. It was hypothesized that a microbe-depleted diet can favor the alteration of the human intestinal microbial ecosystem, therefore contributing to the onset of chronic metabolic and immune diseases currently recognized as the most significant causes of death in the developed world. Here, we studied the microorganisms that are associated with commercial ready-to-eat rocket salads produced through different farming practices. We showed that rocket salad (a widely consumed vegetal food frequently eaten raw) may be a source of lactic acid bacteria and other microbes that can survive gastrointestinal transit, potentially increasing the biodiversity of the intestinal microbiota. This deduction may be valid for virtually all vegetal foods that are consumed raw.

Explanatory integration and integrated explanations in Darwinian medicine and evolutionary medicine

Recently, two research traditions that bring together evolutionary biology and medicine, that is to say, Darwinian medicine and evolutionary medicine, have been identified. In this paper, I analyse these two research traditions with respect to explanatory and interdisciplinary integration. My analysis shows that Darwinian medicine does not integrate medicine and evolutionary biology in any strong sense but does incorporate evolutionary concepts into medicine. I also show that backward-looking explanations in Darwinian medicine are not integrated proximate-and-ultimate explanations but functional explanations that include reference to evolutionary concepts. Nevertheless, explanations in Darwinian medicine have heuristic roles as they potentially contribute to conceptual change and tie pieces of knowledge from different fields of medical research together. I argue that Darwinian medicine is an "interfield" that fosters cross-disciplinary exchange between evolutionary biologists and medical researchers and practitioners based on division of labour and separation, rather than unity. Research in evolutionary medicine, on the other hand, happens at the intersection of evolutionary biology and medicine where the two disciplines are already integrated and is designed to produce entangled proximate-evolutionary explanations. My analysis thus adds another important aspect to the philosophical discussion on the distinction between Darwinian medicine and evolutionary medicine.

Ancient pathogens provide a window into health and well-being

This perspective draws on the record of ancient pathogen genomes and microbiomes illuminating patterns of infectious disease over the course of the Holocene in order to address the following question. How did major changes in living circumstances involving the transition to and intensification of farming alter pathogens and their distributions? Answers to this question via ancient DNA research provide a rapidly expanding picture of pathogen evolution and in concert with archaeological and historical data, give a temporal and behavioral context for heath in the past that is relevant for challenges facing the world today, including the rise of novel pathogens.

Nurturing by nutrition: On the future of gut microbiota management strategies for autoimmune disease

The incidence of autoimmune disease continues to rise, which urges for new prevention and treatment modalities. The composition of the gut microbiota is associated with both susceptibility and progression of disease. Nutrition significantly shapes the gut microbial composition, and poses as such a modality for both prevention and treatment/adjuvant therapy. At very young age, nutritional intervention targeting the gut microbiota is still possible within a one-size-fits all regime, accompanied by a relatively high effect size. As ageing results in higher interindividual variation induced by cumulative exposome factors, a more personalized approach is needed, having a higher effect size than that of current nutritional intervention. As such, supplementation of microbial consortia consisting of keystone taxa and microbial guilds that are involved in the pathophysiology seem a promising direction to lower the burden of autoimmune disease.

Does childhood exposure to biodiverse greenspace reduce the risk of developing asthma?

The prevalence of inflammatory diseases is increasing in populations throughout the industrialized world. An increasing proportion of human populations grow up and live in urban areas, probably with reduced exposure to biodiversity, including diverse soil biotas. Decreased exposure to microorganisms from natural environments, in particular in early childhood, has been hypothesized to hamper development of the human immune system and lead to increasing risks of inflammatory diseases, such as asthma. We investigated 40,249 Danish individuals born 1995-2015. Percentage greenspace was assessed in a 2 km buffer around home addresses of individuals. The Danish Biodiversity Map, charting occurrence density of red-listed animals, plants and macrofungi, was used as a proxy for multi-taxon biodiversity. For asthma defined broadly, we found no evidence of decreasing risk of developing asthma with higher levels of biodiversity, while greenspace exposure was associated with higher risk of asthma. In contrast, exposure to total and biodiverse greenspace was associated with reduced risk of developing severe asthma. Exposure to farmland, which in Denmark is heavily industrialized cropland, also showed association with elevated risk of developing asthma, even at relatively low agricultural landcover. In the subset of children growing up in highly urbanized settings, we found high exposures to urban greenspace to be associated with reduced risk of developing asthma. Our results lend limited support to the hypothesis that childhood exposure to biodiverse environments reduces the risk of acquiring inflammatory diseases later in life. However, access to urban greenspace, such as parks, which typically harbour low levels of biodiversity, seems to reduce asthma risk, potentially through exposure to common soil microbiota. Our results suggest that effects of biodiversity exposure on human health is set by a balance between ecosystem services and disservices and that biodiversity conservation is best motivated with other arguments than reduction of risks from inflammatory diseases.

Hygienic behaviors during the COVID-19 pandemic may decrease immunoglobulin G levels: Implications for Kawasaki disease

Background

Due to the coronavirus disease 2019 (COVID-19) pandemic, hygienic behaviors became a new norm since January 2020. The hygiene hypothesis predicts that an excessively hygienic environment may adversely affect human health.

Objective

We quantified the effect of COVID-19 on immunological parameters linked to the hygiene hypothesis.

Methods

We examined age-specific levels of total nonspecific immunoglobulin G (IgG) and IgE in individuals who visited Fukuoka Tokushukai Hospital between 2010 and 2021. Pre-COVID (2010–2019) and COVID (2020–2021) periods were compared.

Results

IgG levels steadily decreased throughout Pre-COVID period. IgG levels fell abruptly from the pre-COVID period to the COVID period in all age groups (P = 0.0271, < 0.3 years; P = 0.0096, 0.3–5 years; P = 0.0074, ≥ 5 years). The declines in IgG in < 0.3 years and that in ≥ 5 years accelerated during the COVID period. IgE levels were seasonal, but did not change noticeably from the pre-COVID to COVID period. IgG levels recorded for patients with Kawasaki disease (KD) (mean 709 mg/dL) were significantly lower than for matched control subjects (826 mg/dL) (P<0.0001).

Discussion

Hygienic behaviors during the COVID-19 outbreak decreased the chance of infection, which may explain the decreases in IgG levels in children and adults. Neonatal IgG declined, possibly because of the decrease in maternal IgG.

Conclusion

Hygienic behaviors decreased the IgG levels in all age groups, from neonates to adults. This downturn in IgG may lead to vulnerability to infections as well as to KD.

Multiple nutritional and gut microbial factors associated with allergic rhinitis: the Hitachi Health Study

Several studies suggest the involvement of dietary habits and gut microbiome in allergic diseases. However, little is known about the nutritional and gut microbial factors associated with the risk of allergic rhinitis (AR). We recruited 186 participants with symptoms of AR and 106 control subjects without symptoms of AR at the Hitachi Health Care Center, Japan. The habitual consumption of 42 selected nutrients were examined using the brief-type self-administered diet history questionnaire. Faecal samples were collected and subjected to amplicon sequencing of the 16S ribosomal RNA gene hypervariable regions. Association analysis revealed that four nutrients (retinol, vitamin A, cryptoxanthin, and copper) were negatively associated with AR. Among 40 genera examined, relative abundance of Prevotella and Escherichia were associated with AR. Furthermore, significant statistical interactions were observed between retinol and Prevotella. The age- and sex-adjusted odds of AR were 25-fold lower in subjects with high retinol intake and high Prevotella abundance compared to subjects with low retinol intake and low Prevotella abundance. Our data provide insights into complex interplay between dietary nutrients, gut microbiome, and the development of AR.

Concurrent allergy and helminthiasis in underprivileged urban South African adults previously residing in rural areas

This study investigated whether prior exposure to helminths (Ascaris IgE, Ascaris eggs and Trichuris eggs) either in childhood or in adulthood, and residence in rural and resource‐limited urban areas influence allergy outcomes (asthma, rhinitis, IgE atopy and food allergy) in a South African population. Participants historical and present allergies data were collected through questionnaires and clinical record files. Coproscopy and immunoassays (ImmunoCAP^TM Phadiatop, total IgE and allergen‐specific fx3 IgE immunoassays and Ascaris IgE radioallergosorbent [RAST] tests) were used for active helminthiasis and allergy screens respectively. Data were analysed using logistic regression analysis, and models were adjusted for age, gender and locality. High Ascaris IgE was significantly associated with asthma (adjusted odds ratio [aOR] = 2.20, p = .047), IgE atopy (aOR = 18.18, p < .0001) and food allergy (aOR = 14.47, p < .0001). Asthma was significantly less likely among participants with Ascaris eggs (aOR = 0.43, p = .048) and Trichuris eggs (aOR = 0.36, p = .024). The findings of co‐occurrent helminthiasis and allergic disorders in a population that has resided both in rural and peri‐urban informal settlements both oppose and agree with two main notions of the hygiene hypothesis that (i) individuals residing in rural settings with poor sanitation and geohelminth infection are less prone to allergy, and (ii) helminth infections protect against allergy respectively. Further research is warranted.

Atopic diseases and airway-related symptoms in Bavarian pre-schoolers: determinants and association with immunization

BACKGROUND

Atopic diseases are among the most common chronic conditions in childhood. Causes of allergies are manifold. The aim of this paper is to evaluate risk factors for atopic diseases and unremitting wheeze and to examine if there is an association between measles, mumps and rubella (MMR) vaccination and atopic dermatitis, asthma and unremitting wheeze in Bavarian pre-schoolers.

METHODS

Parents filled out a questionnaire on children's health and environmental and socioeconomic factors. The questionnaire was administered within the Health Monitoring Units in a cross-sectional study in Bavaria, Germany (2014/2015). Data on vaccinations were obtained via the School Entrance Examination, a mandatory examination for pre-school children in Bavaria. Rates of influential factors of atopic diseases and wheeze, MMR and DTP (diphtheria, pertussis and tetanus) vaccination were calculated for all children stratified by health outcomes. To examine if there is an association between MMR vaccination and health outcomes, a multiple logistic regression analysis was performed.

RESULTS

Data were available for 3237 individuals. Symptoms and diseases were more frequent in boys. Higher parental education was associated with a higher prevalence of atopic dermatitis. There were no significant associations between any of the health outcome groups and MMR vaccination in the multiple logistic regression models with adjustment for potential confounders.

CONCLUSIONS

The present study is in line with the current state of research that MMR vaccination is not associated with atopic diseases.

Helminth infections and cardiovascular diseases: A role for the microbiota and Mϕs?

Cardiovascular diseases are rising in developing countries with increasing urbanization and lifestyle changes and remains a major cause of death in the developed world. In this mini review, we discuss the possibility that the effect of helminth infections on the immune system and the microbiota may affect risk factors in cardiovascular diseases such as atherosclerosis, as part of the hygiene hypothesis. The effects of Type 2 immune responses induced by helminths and helminth derived molecules on regulating metabolism and Mϕ function could be a mechanistic link for further investigation. We emphasize the complexity and difficulties in determining indirect or direct and causal relationships between helminth infection status and cardiovascular diseases. New experimental models, such as rewilding laboratory mice, whereby different aspects of the environment and host genetics can be carefully dissected may provide further mechanistic insights and therapeutic strategies for treating cardiovascular diseases.

Respiratory Viral and Bacterial Factors That Influence Early Childhood Asthma

Asthma is a chronic respiratory condition characterised by episodes of shortness of breath due to reduced airway flow. The disease is triggered by a hyperreactive immune response to innocuous allergens, leading to hyper inflammation, mucus production, changes in structural cells lining the airways, and airway hyperresponsiveness. Asthma, although present in adults, is considered as a childhood condition, with a total of about 6.2 million children aged 18 and below affected globally. There has been progress in understanding asthma heterogeneity in adults, which has led to better patient stratification and characterisation of multiple asthma endotypes with distinct, but overlapping inflammatory features. The asthma inflammatory profile in children is not well-defined and heterogeneity of the disease is less described. Although many factors such as genetics, food allergies, antibiotic usage, type of birth, and cigarette smoke exposure can influence asthma development particularly in children, respiratory infections are thought to be the major contributing factor in poor lung function and onset of the disease. In this review, we focus on viral and bacterial respiratory infections in the first 10 years of life that could influence development of asthma in children. We also review literature on inflammatory immune heterogeneity in asthmatic children and how this overlaps with early lung development, poor lung function and respiratory infections. Finally, we review animal studies that model early development of asthma and how these studies could inform future therapies and better understanding of this complex disease.

Supplementation of a lacto-fermented rapeseed-seaweed blend promotes gut microbial- and gut immune-modulation in weaner piglets

BACKGROUND

The direct use of medical zinc oxide in feed will be abandoned after 2022 in Europe, leaving an urgent need for substitutes to prevent post-weaning disorders.

RESULTS

This study investigated the effect of using rapeseed-seaweed blend (rapeseed meal added two brown macroalgae species Ascophylum nodosum and Saccharina latissima) fermented by lactobacilli (FRS) as feed ingredients in piglet weaning. From d 28 of life to d 85, the piglets were fed one of three different feeding regimens (n = 230 each) with inclusion of 0%, 2.5% and 5% FRS. In this period, no significant difference of piglet performance was found among the three groups. From a subset of piglets (n = 10 from each treatment), blood samples for hematology, biochemistry and immunoglobulin analysis, colon digesta for microbiome analysis, and jejunum and colon tissues for histopathological analyses were collected. The piglets fed with 2.5% FRS manifested alleviated intraepithelial and stromal lymphocytes infiltration in the gut, enhanced colon mucosa barrier relative to the 0% FRS group. The colon microbiota composition was determined using V3 and V1-V8 region 16S rRNA gene amplicon sequencing by Illumina NextSeq and Oxford Nanopore MinION, respectively. The two amplicon sequencing strategies showed high consistency between the detected bacteria. Both sequencing strategies indicated that inclusion of FRS reshaped the colon microbiome of weaned piglets with increased Shannon diversity. Prevotella stercorea was verified by both methods to be more abundant in the piglets supplied with FRS feed, and its abundance was positively correlated with colonic mucosa thickness but negatively correlated with blood concentrations of leucocytes and IgG.

CONCLUSIONS

FRS supplementation relieved the gut lymphocyte infiltration of the weaned piglets, improved the colon mucosa barrier with altered microbiota composition. Increasing the dietary inclusion of FRS from 2.5% to 5% did not lead to further improvements.

Immune-mediated inflammatory diseases and nutrition: results from an online survey on patients' practices and perceptions

Background

The central role of microbiota and the contribution of diet in immune-mediated inflammatory diseases (IMID) are increasingly examined. However, patients’ perspectives on nutrition and its impact on their disease has not received a lot of attention. We aimed to directly collect information from patients with IMID about their dietary behaviors and their perceptions of the influence of nutrition on their disease.

Methods

Adult patients with rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis, Crohn’s disease, ulcerative colitis or psoriasis registered in an online patient community were invited to participate in the study and complete an online self-administered questionnaire. We assessed patients’ dietary knowledge and choices by collecting information on the diet regimens they were following or recommended and their perceptions of the diet and its consequences on their disease.

Results

Fifty patients per target disease were included with a mean age of 48.1 years (95%CI 46.7–49.6). Other sociodemographic and clinical characteristics varied across the diseases. Since diagnosis, 44% of the patients changed their eating habits, mainly patients with inflammatory bowel disease with 69% of these making the change on their own initiative. Patients who did not change their diet habits reported not having received nutritional advice from their healthcare professionals (HCP) in 69% of the cases. The perceived impact of nutrition on their symptoms was mixed (overall 74% of the patients reported positive consequences and 60% negative ones) and varied across the diseases. Patients with psoriasis only experienced positive consequences from changing their diet, such as reduction of stress and improved mental health, while patients with Crohn’s disease reported more negative effects such as increased fatigue and disturbed sleep. Patients with rheumatic diseases and ulcerative colitis reported weight loss and better physical fitness, but also increased fatigue.

Conclusions

Even if differences exist across diseases, the importance of nutrition and its potential positive role in symptom management is acknowledged by the majority of the patients. However, there is a need and a demand from patients to receive more dietary advice. Developing therapeutic education tools on nutrition for people with IMID and involving patients’ organizations would provide useful information and encourage communication between HCP and patients.

The ammonia oxidizing bacterium Nitrosomonas eutropha blocks T helper 2 cell polarization via the anti-inflammatory cytokine IL-10

The prevalence of atopic diseases has been steadily increasing since the mid twentieth century, a rise that has been linked to modern hygienic lifestyles that limit exposure to microbes and immune system maturation. Overactive type 2 CD4+ helper T (Th2) cells are known to be closely associated with atopy and represent a key target for treatment. In this study, we present an initial characterization of ammonia oxidizing bacteria (AOB) Nitrosomonas eutropha D23, an environmental microbe that is not associated with human pathology, and show AOB effectively suppress the polarization of Th2 cells and production of Th2-associated cytokines (IL-5, IL-13, and IL-4) by human peripheral blood mononuclear cells (PBMC). We show that AOB inhibit Th2 cell polarization not through Th1-mediated suppression, but rather through mechanisms involving the anti-inflammatory cytokine IL-10 and the potential inhibition of dendritic cells, as evidenced by a reduction in Major Histocompatibility Complex Class II (MHC II) and CD86 expression following AOB treatment. This is the first report of immunomodulatory properties of AOB, and provides initial support for the development of AOB as a potential therapeutic for atopic diseases.

[The skin microbiome as a natural protection factor : Insights from basic research]

Hintergrund

Eine neue Generation von Technologien deckt eine große Zahl von Mikroorganismen auf, die mit der Haut in einer engen und oft funktionellen Beziehung stehen. Störungen dieser Partnerschaft haben erhebliche Konsequenzen. Seit Jahrzehnten schreitet die Verarmung des Mikrobioms im Zuge eines modernen, globalisierten Lebensstils voran. Bei der Aufrechterhaltung der Gesundheit sind neben den genetischen Aspekten auch die auf der Haut und anderen Organen lebenden Mikroben zu berücksichtigen. Alle Epithelien einschließlich der Haut sind mit einer Vielzahl von Mikroben besiedelt.

Fragestellung

Betrachtet wird die Funktion des Mikrobioms in der Haut und anderen Organen.

Material und Methode

Es erfolgt eine Diskussion von Grundlagenarbeiten.

Ergebnisse

Das Mikrobiom der Haut ist für die Aufrechterhaltung der Gesundheit von großer Bedeutung.

Schlussfolgerungen

Wir brauchen das Verständnis unseres Körpers als multiorganismischer Metaorganismus, um intelligent auf die Herausforderungen einer sich immer rascher ändernden Umwelt reagieren zu können.

The interplay between Trichuris and the microbiota

Parasitic worms are amongst the most common pathogens to infect humans and have a long-established history of inflicting disease in their hosts. There is a large body of evidence that states intestine-dwelling helminths ensure their survival by influencing the host immune response against them. In recent years, it has become apparent that the large and diverse microbial communities that exist in the gastrointestinal (GI) tract of the host and within the parasite itself have a pivotal role in worm survival and persistence. Using a variety of mouse models (including laboratory, germ-free and rewilded mice), there have been new insights into how bacteria and worms interact with each other; this includes the discovery that Trichuris is unable to hatch and/or infect their host in the absence of bacteria, and that these worms contain a Trichuris-specific gut microbiota. These interactions are determined in part by the capacity of the host, gut microbiota and worms to communicate via metabolites such as butyrate, which are microbially derived and have known immunoregulatory properties. By exploring the contribution of gut bacteria to worm infections and the intricate relationship that exists between them, an exciting and emerging field in whipworm parasitology is established.

Microbial exposures that establish immunoregulation are compatible with targeted hygiene

It is often suggested that hygiene is not compatible with the microbial exposures that are necessary for establishment of the immune system in early life. However, when we analyze the microbial exposures of modern humans in the context of human evolution and history, it becomes evident that whereas children need exposure to the microbiotas of their mothers, other family members, and the natural environment, exposure to the unnatural microbiota of the modern home is less relevant. In addition, any benefits of exposure to the infections of childhood within their household setting are at least partly replaced by the recently revealed nonspecific effects of vaccines. This article shows how targeting hygiene practices at key risk moments and sites can maximize protection against infection while minimizing any impact on essential microbial exposures. Moreover, this targeting must aim to reduce direct exposure of children to cleaning agents because those agents probably exert T_H2-adjuvant effects that trigger allergic responses to normally innocuous antigens. Finally, we need to halt the flow of publications in the scientific literature and the media that blame hygiene for the increases in immunoregulatory disorders. Appropriately targeted hygiene behavior is compatible with a healthy lifestyle that promotes exposure to essential microorganisms.

Experimental Drugs with the Potential to Treat Atopic Eczema

INTRODUCTION

Eczema or atopic dermatitis (AD) is a chronically relapsing dermatosis characterized by pruritus and a significant impact on the quality of life.

METHODS

The authors undertook a structured search of peer-reviewed research articles from PubMed and Google Scholar. Recent and up-to-date studies relevant to the topic were included.

RESULTS

This report overviews current treatment and experimental drug for AD. Topical agents including topical phosphodiesterase E4 (PDE4) inhibitors such as crisaborole are efficacious in the treatment of AD with few side effects. Monoclonal antibodies such as dupilumab given subcutaneously are efficacious for more severe disease. Systemic treatment can ameliorate symptoms in severe and recalcitrant AD. New systemic treatment includes several traditional herbal formulations that have undergone clinical trials using modern research methodology to determine their efficacy and safety. AD is associated with many complicating psychosocial issues. Often suboptimal efficacy is due to unrealistic expectations and poor compliance making treatment difficult in spite of effective treatment and efforts in drug discovery. Randomized trials have shown that novel topical and subcutaneous medications are safe and efficacious. Regarding herbs, a methodology for the investigation of herbal medications is often flawed and scientific evidence is lacking. Experimental drugs include various biologics, PDE4 and JAK inhibitors in topical, oral, subcutaneous or intravenous forms are in various phases of trials.

CONCLUSION

Many novel medications demonstrate efficacy for AD. Experimental drugs include various biologics, PDE4 and JAK inhibitors are in various phases of trials.

Fee equalization and appropriate health care

Fee equalization in health care brings under a unique tariff several medical treatments, coded under different Diagnosis Related Groups (DRGs). The aim is to improve healthcare quality and efficiency by discouraging unnecessary, but better-paid, treatments. We evaluate its effectiveness on childbirth procedures to reduce overuse of c-sections by equalizing the DRGs for vaginal and cesarean deliveries. Using data from Italy and a difference-in-differences approach, we show that setting an equal fee decreased c-sections by 2.6%. This improved the appropriateness of medical decisions, with more low-risk mothers delivering naturally and no significant changes in the incidence of complications for vaginal deliveries. Our analysis supports the effectiveness of fee equalization in avoiding c-sections, but highlights the marginal role of financial incentives in driving c-section overuse. The observed drop was only temporary and in about a year the use of c-sections went back to the initial level. We found a greater reduction in lower quality, more capacity-constrained hospitals. Moreover, the effect is driven by districts where the availability of Ob-Gyn specialists is higher and where women are predominant in the gender composition of Ob-Gyn specialists.

Coronavirus disease-2019 and the intestinal tract: An overview

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection can progress to a severe respiratory and systemic disease named coronavirus disease-2019 (COVID-19). The most common symptoms are fever and respiratory discomfort. Nevertheless, gastrointestinal infections have been reported, with symptoms such as diarrhea, nausea, vomiting, abdominal pain, and lack of appetite. Importantly, SARS-CoV-2 can remain positive in fecal samples after nasopharyngeal clearance. After gastrointestinal SARS-CoV-2 infection and other viral gastrointestinal infections, some patients may develop alterations in the gastrointestinal microbiota. In addition, some COVID-19 patients may receive antibiotics, which may also disturb gastrointestinal homeostasis. In summary, the gastrointestinal system, gut microbiome, and gut-lung axis may represent an important role in the development, severity, and treatment of COVID-19. Therefore, in this review, we explore the current pieces of evidence of COVID-19 gastrointestinal manifestations, possible implications, and interventions.

Out of balance: the role of evolutionary mismatches in the sex disparity in autoimmune disease

Over the past century autoimmune disease incidence has increased rapidly in (post-) industrialised, affluent societies, suggesting that changes in ecology and lifestyle are driving this development. Epidemiological studies show that (i) 80% of autoimmune disease patients are female, (ii) autoimmune diseases co-occur more often in women, and (iii) the incidence of some autoimmune diseases is increasing faster in women than in men. The female preponderance in autoimmunity is most pronounced between puberty and menopause, suggesting that diverging sex hormone levels during the reproductive years are implicated in autoimmune disease development. Using an evolutionary perspective, we build on the hypotheses that female immunity is cyclical in menstruating species and that natural selection shaped the female immune system to optimise the implantation and gestation of a semi-allogeneic foetus. We propose that cyclical immunomodulation and female immune tolerance mechanisms are currently out of balance because of a mismatch between the conditions under which they evolved and (post-)industrialised, affluent lifestyles. We suggest that current changes in autoimmune disease prevalence may be caused by increases in lifetime exposure to cyclical immunomodulation and ovarian hormone exposure, reduced immune challenges, increased reproductive lifespan, changed reproductive patterns, and enhanced positive energy balance associated with (post-)industrialised, affluent lifestyles. We discuss proximate mechanisms by which oestrogen and progesterone influence tolerance induction and immunomodulation, and review the effect of the menstrual cycle, pregnancy, and contraceptive use on autoimmune disease incidence and symptoms.

Schistosome Infection and Schistosome-Derived Products as Modulators for the Prevention and Alleviation of Immunological Disorders

Parasitic helminths, comprising the flatworms (tapeworms and flukes) and nematodes (roundworms), have plagued humans persistently over a considerable period of time. It is now known that the degree of exposure to these and other pathogens inversely correlates with the incidence of both T helper 1 (Th1)-mediated autoimmunity and Th2-mediated allergy. Accordingly, there has been recent increased interest in utilizing active helminth worm infections and helminth-derived products for the treatment of human autoimmune and inflammatory diseases and to alleviate disease severity. Indeed, there is an accumulating list of novel helminth derived molecules, including proteins, peptides, and microRNAs, that have been shown to exhibit therapeutic potential in a variety of disease models. Here we consider the blood-dwelling schistosome flukes, which have evolved subtle immune regulatory mechanisms that promote parasite survival but at the same time minimize host tissue immunopathology. We review and discuss the recent advances in using schistosome infection and schistosome-derived products as therapeutics to treat or mitigate human immune-related disorders, including allergic asthma, arthritis, colitis, diabetes, sepsis, cystitis, and cancer.

The hygiene hypothesis, the COVID pandemic, and consequences for the human microbiome

The COVID-19 pandemic has the potential to affect the human microbiome in infected and uninfected individuals, having a substantial impact on human health over the long term. This pandemic intersects with a decades-long decline in microbial diversity and ancestral microbes due to hygiene, antibiotics, and urban living (the hygiene hypothesis). High-risk groups succumbing to COVID-19 include those with preexisting conditions, such as diabetes and obesity, which are also associated with microbiome abnormalities. Current pandemic control measures and practices will have broad, uneven, and potentially long-term effects for the human microbiome across the planet, given the implementation of physical separation, extensive hygiene, travel barriers, and other measures that influence overall microbial loss and inability for reinoculation. Although much remains uncertain or unknown about the virus and its consequences, implementing pandemic control practices could significantly affect the microbiome. In this Perspective, we explore many facets of COVID-19-induced societal changes and their possible effects on the microbiome, and discuss current and future challenges regarding the interplay between this pandemic and the microbiome. Recent recognition of the microbiome's influence on human health makes it critical to consider both how the microbiome, shaped by biosocial processes, affects susceptibility to the coronavirus and, conversely, how COVID-19 disease and prevention measures may affect the microbiome. This knowledge may prove key in prevention and treatment, and long-term biological and social outcomes of this pandemic.

GAS6 signaling tempers Th17 development in patients with multiple sclerosis and helminth infection

Multiple sclerosis (MS) is a highly disabling neurodegenerative autoimmune condition in which an unbalanced immune response plays a critical role. Although the mechanisms remain poorly defined, helminth infections are known to modulate the severity and progression of chronic inflammatory diseases. The tyrosine kinase receptors TYRO3, AXL, and MERTK (TAM) have been described as inhibitors of the immune response in various inflammatory settings. We show here that patients with concurrent natural helminth infections and MS condition (HIMS) had an increased expression of the negative regulatory TAM receptors in antigen-presenting cells and their agonist GAS6 in circulating CD11b^high and CD4⁺ T cells compared to patients with only MS. The Th17 subset was reduced in patients with HIMS with a subsequent downregulation of its pathogenic genetic program. Moreover, these CD4⁺ T cells promoted lower levels of the co-stimulatory molecules CD80, CD86, and CD40 on dendritic cells compared with CD4⁺ T cells from patients with MS, an effect that was GAS6-dependent. IL-10⁺ cells from patients with HIMS showed higher GAS6 expression levels than Th17 cells, and inhibition of phosphatidylserine/GAS6 binding led to an expansion of Th17 effector genes. The addition of GAS6 on activated CD4⁺ T cells from patients with MS restrains the Th17 gene expression signature. This cohort of patients with HIMS unravels a promising regulatory mechanism to dampen the Th17 inflammatory response in autoimmunity.

Helminths have co-evolved with human civilization, and the rapid exclusion from their environment, in the last few decades, has tremendously affected the immune development and regulation. Moreover, several epidemiological studies have shown an inverse correlation between the exposure of these organisms and the development of autoimmunity in industrialized countries. In this sense, helminth therapy appears to be a promising concept to oppose chronic inflammatory and autoimmune diseases because they are master manipulators of host immunity, albeit the mechanisms remain poorly defined. For this reason, it is essential to decipher the main regulatory pathways to hijack the immune response in the absence of parasite infection. Our research described how helminth infection promotes regulatory mechanisms based on the tyrosine kinase TYRO3, AXL, MERTK (TAM) receptors, and their ligand GAS6 to dampen Th17 development and the inflammatory response in patients with multiple sclerosis (MS), a neurodegenerative autoimmune disorder. We show here that GAS6 plays a critical role in the regulation of pro-inflammatory cytokines, transcriptional programs, and plasticity of IL-17 subset. Our work substantiates the hypothesis that enhancing the TAM axis in a manner similar to helminth infection could be a promising alternative for autoimmune diseases.

The Spectrum of Gastrointestinal Symptoms in Patients With Coronavirus Disease-19: Predictors, Relationship With Disease Severity, and Outcome

INTRODUCTION

We prospectively studied the frequency, spectrum, and predictors of gastrointestinal (GI) symptoms among patients with coronavirus disease-19 (COVID-19) and the relationship between GI symptoms and the severity and outcome.

METHODS

Consecutive patients with COVID-19, diagnosed in a university hospital referral laboratory in northern India, were evaluated for clinical manifestations including GI symptoms, their predictors, and the relationship between the presence of these symptoms, disease severity, and outcome on univariate and multivariate analyses.

RESULTS

Of 16,317 subjects tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA in their oropharyngeal and nasopharyngeal swabs during April-May 2020, 252 (1.5%) were positive. Of them, 208 (82.5%) were asymptomatic; of the 44 symptomatic patients, 18 (40.9%) had non-GI symptoms, 15 (34.1%) had a combination of GI and non-GI symptoms, and 11 (25.0%) had GI symptoms only. Thirty-three had mild-to-moderate disease, 8 severe, and 5 critical. Five patients (1.98%) died. On multivariate analysis, the factors associated with the presence of GI symptoms included the absence of contact history and presence of non-GI symptoms and comorbid illnesses. Patients with GI synptoms more often had severe, critical illness and fatal outcome than those without GI symptoms.

DISCUSSION

Eighty-two percent of patients with COVID-19 were asymptomatic, and 10.3% had GI symptoms; severe and fatal disease occurred only in 5% and 2%, respectively. The presence of GI symptoms was associated with a severe illness and fatal outcome on multivariate analysis. Independent predictors of GI symptoms included the absence of contact history, presence of non-GI symptoms, and comorbid illnesses.(Equation is included in full-text article.).

Therapeutic Potential of the Intestinal Microbiota for Immunomodulation of Food Allergies

Food allergy is an atopic disease that is caused by the immune system targeting harmless food antigens that can result in life-threatening anaphylaxis. As humans and microbes have co-evolved, inevitably commensal microbes have a tremendous impact on our health. As such, the gut with its enormous microbial richness reflects a highly tolerogenic environment at steady state, in which immune cells are educated to react in a well-calibrated manner to food and microbial antigens. Recent evidence indicates that the susceptibility to food allergy is critically linked to microbial dysbiosis and can be transmitted by microbial transfer from humans to mice. Experimental work and epidemiological studies further point toward a critical time window in early childhood during which the immune system is imprinted by microbial colonization. Particularly, Foxp3-expressing regulatory T cells turn out to be key players, acting as rheostats for controlling the magnitude of food allergic reactions. An increasing number of bacterial metabolites has recently been shown to regulate directly or indirectly the differentiation of peripherally induced Tregs, most of which co-express the RAR-related orphan receptor gamma t (RORγt). Genetic ablation provided additional direct evidence for the importance of RORγt+ Tregs in food allergy. Future strategies for the stratification of food allergic patients with the aim to manipulate the intestinal microbiota by means of fecal transplantation efforts, pre- or probiotic regimens or for boosting oral immunotherapy may improve diagnosis and therapy. In this review some of the key underlying mechanisms are summarized and future directions for potential microbial therapy are explored.

P2X receptors and trigeminal neuralgia

There is currently no effective cure for trigeminal neuralgia (TN) - a relatively common disease that causes long-term pain in patients. Previous research has shown that ionotropic ATP signaling through excitatory and calcium-permeable P2X receptor channels plays a critical role in pathological pain generation and maintenance. In this paper, we review several hypotheses on the pathogenic mechanisms underlying TN. We further discuss pathways or agents that can target P2X expression in TN, thereby affecting pain induction and maintenance.

Distinct inactivated bacterial-based immune modulators vary in their therapeutic efficacies for treating disease based on the organ site of pathology

Recent developments in understanding how the functional phenotype of the innate immune system is programmed has led to paradigm-shifting views on immunomodulation. These advances have overturned two long-held dogmas: (1) only adaptive immunity confers immunological memory; and, (2) innate immunity lacks specificity. This work describes the observation that innate immune effector cells appear to be differentially recruited to specific pathological sites when mobilized by distinct inactivated bacterial-based stimuli administered subcutaneously. The studies presented suggest that the immune system, upon detecting the first signs of a potential infection by a specific pathogen, tends to direct its resources to the compartment from which that pathogen is most likely originating. The findings from this work puts forth the novel hypothesis that the immunotherapeutic efficacy of a microbial-based stimulus for innate immune mobilization depends on the correct selection of the microbial species used as the stimulant and its relationship to the organ in which the pathology is present.

Maternal exposure to antibiotics increases the risk of infant eczema before one year of life: a meta-analysis of observational studies

BACKGROUND

There are some conflicting evidences showing that maternal exposure to antibiotics may increase the risk of infant eczema. The present study aims to estimate the effect of prenatal antibiotics administration on infant eczema.

METHODS

According to the established inclusion criteria, eligible observational studies were collected by comprehensive database search. The qualities of the included studies were assessed using the Newcastle-Ottawa Scale. Effect sizes that were adjusted by multivariable models were extracted and combined. Publication bias was evaluated by visual inspection of funnel plot.

RESULTS

A total of seven observational studies were included. The qualities of the included studies were at moderate or high level. Prenatal antibiotics use was positively associated with eczema before one year of age [odds ratio (OR) = 1.93, 95% confidence interval (CI) 1.35-2.76]. In addition, antibiotics exposure in utero was likely to be related to eczema after one year of age (OR 1.21, 95% CI 0.98-1.49). The exposure to antibiotics during third trimester was not associated with infant eczema (OR 0.97, 95% CI 0.86-1.09).

CONCLUSIONS

Maternal exposure to antibiotics is associated with eczema by one-year age and may have a prolonged effect on eczema after 1-year age. The influence of timing of antibiotics exposure during pregnancy needs more studies to clarify.

Building upon current knowledge and techniques of indoor microbiology to construct the next era of theory into microorganisms, health, and the built environment

In the constructed habitat in which we spend up to 90% of our time, architectural design influences occupants' behavioral patterns, interactions with objects, surfaces, rituals, the outside environment, and each other. Within this built environment, human behavior and building design contribute to the accrual and dispersal of microorganisms; it is a collection of fomites that transfer microorganisms; reservoirs that collect biomass; structures that induce human or air movement patterns; and space types that encourage proximity or isolation between humans whose personal microbial clouds disperse cells into buildings. There have been recent calls to incorporate building microbiology into occupant health and exposure research and standards, yet the built environment is largely viewed as a repository for microorganisms which are to be eliminated, instead of a habitat which is inexorably linked to the microbial influences of building inhabitants. Health sectors have re-evaluated the role of microorganisms in health, incorporating microorganisms into prevention and treatment protocols, yet no paradigm shift has occurred with respect to microbiology of the built environment, despite calls to do so. Technological and logistical constraints often preclude our ability to link health outcomes to indoor microbiology, yet sufficient study exists to inform the theory and implementation of the next era of research and intervention in the built environment. This review presents built environment characteristics in relation to human health and disease, explores some of the current experimental strategies and interventions which explore health in the built environment, and discusses an emerging model for fostering indoor microbiology rather than fearing it.

Reconciling Hygiene and Cleanliness: A New Perspective from Human Microbiome

The term hygiene is deeply rooted with the concept of maintaining sound health and alertness towards cleanliness, while "hygiene hypothesis" depicts the protective role of microbial community exposure in development of early immunity and initial allergic and aesthetic reactions. The tug-of-war has now been pushed toward the literal term "hygiene" over the "hygiene hypothesis" and has continued with disinfection of all microbial loads from the related environments to avoid infections in humans. With the advancement in the microbiome studies, it became clear that humans possess warm, and significant relationships with diverse microbial community. With this opinion article, we have emphasized on the importance of hygiene hypothesis in immunological responses. We also propose the individual/targeted hygiene instead of application of unanimous hygiene hypothesis. This review also elaborates the common practices that should be employed to maintain hygiene along with the balanced microbiome.

The Cancer Microbiome: Distinguishing Direct and Indirect Effects Requires a Systemic View

The collection of microbes that live in and on the human body - the human microbiome - can impact on cancer initiation, progression, and response to therapy, including cancer immunotherapy. The mechanisms by which microbiomes impact on cancers can yield new diagnostics and treatments, but much remains unknown. The interactions between microbes, diet, host factors, drugs, and cell-cell interactions within the cancer itself likely involve intricate feedbacks, and no single component can explain all the behavior of the system. Understanding the role of host-associated microbial communities in cancer systems will require a multidisciplinary approach combining microbial ecology, immunology, cancer cell biology, and computational biology - a systems biology approach.

The antibody/microbiota interface in health and disease

The human intestine is densely colonized with commensal microbes that stimulate the immune system. While secretory Immunoglobulin (Ig) A is known to play a crucial role in gut microbiota compartmentalization, secretory IgM, and systemic IgG have recently been highlighted in host-microbiota interactions as well. In this review, we discuss important aspects of secretory IgA biology, but rather than focusing on mechanistic aspects of IgA impact on microbiota, we stress the current knowledge of systemic antibody responses to whole gut microbiota, in particular their generation, specificities, and function. We also provide a comprehensive picture of secretory IgM biology. Finally, therapeutic and diagnostic implications of these novel findings for the treatment of various diseases are outlined.

Navigating the Gluten-Free Boom: The Dark Side of Gluten Free Diet

In gluten dependent conditions the gluten free diet is the cornerstone of therapy, decreasing disease activity, improving health and quality of life and treating or preventing the associated complications. Gluten withdrawal implies strict and lifelong elimination not only of wheat, barley, rye, and wheat-contaminated oats, but also of numerous non-nutritional products where components of wheat are often added. Due to multiple reasons the diet is difficult to follow and the long-term adherence is decreased with time. The present review summarizes the dark side of gluten restriction where nutritional deficiencies, toxicity, morbidity, mortality, and mental health problems are reported. The aim being to increase awareness, avoid, detect and treat the side effects and to promote a healthier nutrition, for the patient's benefits.