Differentiation of Murine C2C12 Myoblasts Strongly Reduces the Effects of Myostatin on Intracellular Signaling

Alongside in vivo models, a simpler and more mechanistic approach is required to study the effects of myostatin on skeletal muscle because myostatin is an important negative regulator of muscle size. In this study, myostatin was administered to murine (C2C12) and human (CHQ) myoblasts and myotubes. Canonical and noncanonical signaling downstream to myostatin, related ligands, and their receptor were analyzed. The effects of tumorkines were analyzed after coculture of C2C12 and colon cancer-C26 cells. The effects of myostatin on canonical and noncanonical signaling were strongly reduced in C2C12 cells after differentiation. This may be explained by increased follistatin, an endogenous blocker of myostatin and altered expression of activin receptor ligands. In contrast, CHQ cells were equally responsive to myostatin, and follistatin remained unaltered. Both myostatin administration and the coculture stimulated pathways associated with inflammation, especially in C2C12 cells. In conclusion, the effects of myostatin on intracellular signaling may be cell line- or organism-specific, and C2C12 myotubes seem to be a nonoptimal in vitro model for investigating the effects of myostatin on canonical and noncanonical signaling in skeletal muscle. This may be due to altered expression of activin receptor ligands and their regulators during muscle cell differentiation.Peer reviewe

Correction: Saarinen, N.V.V., et al. Multiplexed High-Throughput Serological Assay for Human Enteroviruses. Microorganismis 2020, 8, 963

The authors wish to make the following corrections to this paper [...

Multiplexed High-Throughput Serological Assay for Human Enteroviruses

Immunological assays detecting antibodies against enteroviruses typically use a single enterovirus serotype as antigen. This limits the ability of such assays to detect antibodies against different enterovirus types and to detect possible type-specific variation in antibody responses. We set out to develop a multiplexed assay for simultaneous detection of antibodies against multiple enterovirus and rhinovirus types encompassing all human infecting species. Seven recombinant VP1 proteins from enteroviruses EV-A to EV-D and rhinoviruses RV-A to RV-C species were produced. Using Meso Scale Diagnostics U-PLEX platform we were able to study antibody reactions against these proteins as well as non-structural enterovirus proteins in a single well with 140 human serum samples. Adults had on average 33-fold stronger antibody responses to these antigens (p < 10−11) compared to children, but children had less cross-reactivity between different enterovirus types. The results suggest that this new high-throughput assay offers clear benefits in the evaluation of humoral enterovirus immunity in children, giving more exact information than assays that are based on a single enterovirus type as antigen

Multiplexed High-Throughput Serological Assay for Human Enteroviruses

Immunological assays detecting antibodies against enteroviruses typically use a single enterovirus serotype as antigen. This limits the ability of such assays to detect antibodies against different enterovirus types and to detect possible type-specific variation in antibody responses. We set out to develop a multiplexed assay for simultaneous detection of antibodies against multiple enterovirus and rhinovirus types encompassing all human infecting species. Seven recombinant VP1 proteins from enteroviruses EV-A to EV-D and rhinoviruses RV-A to RV-C species were produced. Using Meso Scale Diagnostics U-PLEX platform we were able to study antibody reactions against these proteins as well as non-structural enterovirus proteins in a single well with 140 human serum samples. Adults had on average 33-fold stronger antibody responses to these antigens (p < 10−11) compared to children, but children had less cross-reactivity between different enterovirus types. The results suggest that this new high-throughput assay offers clear benefits in the evaluation of humoral enterovirus immunity in children, giving more exact information than assays that are based on a single enterovirus type as antigen

Short‐term direct contact with soil and plant materials leads to an immediate increase in diversity of skin microbiota

Immune-mediated diseases have increased during the last decades in urban environments. The hygiene hypothesis suggests that increased hygiene level and reduced contacts with natural biodiversity are related to the increase in immune-mediated diseases. We tested whether short-time contact with microbiologically diverse nature-based materials immediately change bacterial diversity on human skin. We tested direct skin contact, as two volunteers rubbed their hands with sixteen soil and plant based materials, and an exposure via fabric packets filled with moss material. Skin swabs were taken before and after both exposures. Next-generation sequencing showed that exposures increased, at least temporarily, the total diversity of skin microbiota and the diversity of Acidobacteria, Actinobacteria, Bacteroidetes, Proteobacteria and Alpha-, Beta- and Gammaproteobacteria suggesting that contact with nature-based materials modify skin microbiome and increase skin microbial diversity. Until now, approaches to cure or prevent immune system disorders using microbe-based treatments have been limited to use of a few microbial species. We propose that nature-based materials with high natural diversity, such as the materials tested here, might be more effective in modifying human skin microbiome, and eventually, in reducing immune system disorders. Future studies should investigate how long-term changes in skin microbiota are achieved and if the exposure induces beneficial changes in the immune system markers.Peer reviewe

Impact of Cultivation and Origin on the Fruit Microbiome of Apples and Blueberries and Implications for the Exposome

Vegetables and fruits are a crucial part of the planetary health diet, directly affecting human health and the gut microbiome. The objective of our study was to understand the variability of the fruit (apple and blueberry) microbiome in the frame of the exposome concept. The study covered two fruit-bearing woody species, apple and blueberry, two countries of origin (Austria and Finland), and two fruit production methods (naturally grown and horticultural). Microbial abundance, diversity, and community structures were significantly different for apples and blueberries and strongly influenced by the growing system (naturally grown or horticultural) and country of origin (Austria or Finland). Our results indicated that bacterial communities are more responsive towards these factors than fungal communities. We found that fruits grown in the wild and within home gardens generally carry a higher microbial diversity, while commercial horticulture homogenized the microbiome independent of the country of origin. This can be explained by horticultural management, including pesticide use and post-harvest treatments. Specific taxonomic indicators were identified for each group, i.e., for horticultural apples: Pseudomonas, Ralstonia, and Stenotrophomonas. Interestingly, Ralstonia was also found to be enriched in horticultural blueberries in comparison to such that were home and wildly grown. Our study showed that the origin of fruits can strongly influence the diversity and composition of their microbiome, which means that we are exposed to different microorganisms by eating fruits from different origins. Thus, the fruit microbiome needs to be considered an important but relatively unexplored external exposomic factor

Diverse Environmental Microbiota as a Tool to Augment Biodiversity in Urban Landscaping Materials

Human activities typically lead to simplified urban diversity, which in turn reduces microbial exposure and increases the risk to urban dwellers from non-communicable diseases. To overcome this, we developed a microbial inoculant from forest and agricultural materials that resembles microbiota in organic soils. Three different sand materials (sieved, safety and sandbox) commonly used in playgrounds and other public spaces were enriched with 5 % of the inoculant. Skin microbiota on fingers (identified from bacterial 16S rDNA determined using Illumina MiSeq sequencing) was compared after touching non-enriched and microbial inoculant-enriched sands. Exposure to the non-enriched materials changed the skin bacterial community composition in distinct ways. When the inoculant was added to the materials, the overall shift in community composition was larger and the differences between different sand materials almost disappeared. Inoculant-enriched sand materials increased bacterial diversity and richness but did not affect evenness at the OTU level on skin. The Firmicutes/Bacteroidetes ratio was higher after touching inoculant-enriched compared to non-enriched sand materials. The relative abundance of opportunistic pathogens on skin was 40–50 % before touching sand materials, but dropped to 14 % and 4 % after touching standard and inoculant-enriched sand materials, respectively. When individual genera were analyzed, Pseudomonas sp. and Sphingomonas sp. were more abundant after touching standard, non-enriched sand materials, while only the relative abundance of Chryseobacterium sp. increased after touching the inoculant-enriched materials. As Chryseobacterium is harmless for healthy persons, and as standard landscaping materials and normal skin contain genera that include severe pathogens , the inoculant-enriched materials can be considered safe. Microbial inoculants could be specifically created to increase the proportion of non-pathogenic bacterial taxa and minimize the transfer of pathogenic taxa. We recommend further study into the usability of inoculant-enriched materials and their effects on the bacterial community composition of human skin and on the immune response.Peer reviewe

Association of different enteroviruses with atopy and allergic diseases in early childhood

Background Enterovirus (EV) infections, being among the most prevalent viruses worldwide, have been associated with reduced risk of allergic diseases. We sought to determine the association between EVs and allergic sensitization and disease in early childhood. Methods The study was carried out in a nested case-control setting within a prospective birth cohort in Finland. We included 138 case children who had specific IgE (s-IgE) sensitization at the age of 5 years and 138 control children without s-IgE sensitization. Allergic disease was recorded at study visits and identified with the ISAAC questionnaire. We screened for the presence of serotype-specific antibodies against 41 EVs at 1-5 years of age and assessed their association with allergic sensitization and disease. Results The overall number of EV infections did not differ between s-IgE-sensitized children and non-sensitized control children. However, there was a tendency of case children with an allergic disease having less EV infections than their controls. This observation was statistically significant for species A EVs in case children with atopic dermatitis vs. control children: OR 0.6 (95% CI 0.36-0.99), p = .048. Conclusion This study supports the evidence that EV exposure and development of allergic disease are inversely associated. Interestingly, the inverse association was not observed for bare atopic IgE sensitization, but for IgE sensitization coupled with clinical atopic disease. This suggests that environmental factors influencing IgE sensitization may differ from those influencing progression to clinical allergic disease.Peer reviewe

The abundance of health-associated bacteria is altered in PAH polluted soils-Implications for health in urban areas?

Long-term exposure to polyaromatic hydrocarbons (PAHs) has been connected to chronic human health disorders. It is also well-known that i) PAH contamination alters soil bacterial communities, ii) human microbiome is associated with environmental microbiome, and iii) alteration in the abundance of members in several bacterial phyla is associated with adverse or beneficial human health effects. We hypothesized that soil pollution by PAHs altered soil bacterial communities that had known associations with human health. The rationale behind our study was to increase understanding and potentially facilitate reconsidering factors that lead to health disorders in areas characterized by PAH contamination. Large containers filled with either spruce forest soil, pine forest soil, peat, or glacial sand were left to incubate or contaminated with creosote. Biological degradation of PAHs was monitored using GC-MS, and the bacterial community composition was analyzed using 454 pyrosequencing. Proteobacteria had higher and Actinobacteria and Bacteroidetes had lower relative abundance in creosote contaminated soils than in non-contaminated soils. Earlier studies have demonstrated that an increase in the abundance of Proteobacteria and decreased abundance of the phyla Actinobacteria and Bacteroidetes are particularly associated with adverse health outcomes and immunological disorders. Therefore, we propose that pollution-induced shifts in natural soil bacterial community, like in PAH-polluted areas, can contribute to the prevalence of chronic diseases. We encourage studies that simultaneously address the classic "adverse toxin effect" paradigm and our novel "altered environmental microbiome" hypothesis.Peer reviewe

A 96-well format for a high-throughput baculovirus generation, fast titering and recombinant protein production in insect and mammalian cells

<p>Abstract</p> <p>Background</p> <p>Baculovirus expression vector system (BEVS) has become a standard in recombinant protein production and virus-like particle preparation for numerous applications.</p> <p>Findings</p> <p>We describe here protocols which adapt baculovirus generation into 96-well format.</p> <p>Conclusion</p> <p>The established methodology allows simple baculovirus generation, fast virus titering within 18 h and efficient recombinant protein production in a high-throughput format. Furthermore, the produced baculovirus vectors are compatible with gene expression in vertebrate cells <it>in vitro </it>and <it>in vivo</it>.</p