Single-cell sequencing of the retina shows that LDHA regulates pathogenesis of autoimmune uveitis.

Autoimmune uveitis (AU) is a severe disorder causing poor vision and blindness. However, the cellular dynamics and pathogenic mechanisms underlying retinal injury in uveitis remain unclear. In this study, single-cell RNA sequencing of the retina and cervical draining lymph nodes in experimental autoimmune uveitis mice was conducted to identify the cellular spatiotemporal dynamics and upregulation of the glycolysis-related gene LDHA. Suppression of LDHA can rescue the imbalance of T effector (Teff) cells/T regulator (Treg) cells under inflammation via downregulation of the glycolysis-PI3K signaling circuit and inhibition of the migration of CXCR4+ Teff cells towards retinal tissue. Furthermore, LDHA and CXCR4 are upregulated in the peripheral blood mononuclear cells of Vogt-Koyanagi-Harada patients. The LDHA inhibitor suppresses CD4+ T cell proliferation in humans. Therefore, our data indicate that the autoimmune environment of uveitis regulates Teff cell accumulation in the retina via glycolysis-associated LDHA. Modulation of this target may provide a novel therapeutic strategy for treating AU.

Energy, protein and iron densities of dabi teff-field pea-based optimised novel complementary flour and its contribution to daily energy and nutrients demand by 6-23-month-old children.

Inadequate intake of age-specific energy and nutrients is among the prime immediate causes of child malnutrition. Thus, this study aimed to determine the energy, protein and Fe densities of pre-processed dabi teff-field pea-based optimised novel complementary flour and its contribution to daily energy and nutrients demand by 6-8, 9-11 and 12-23 month-old children. The optimal formula at overall optimisation was identified to be 34·66 % dabi teff, 25 % barley, 15 % oats, 15·34 % field pea, 5 % linseed and 5 % maize with response values of 15·74 % protein, 5·09 % fat, 2·26 % ash, 2·88 % fibre, 73·05 % carbohydrate, 1591·72 kJ/100 g (380·43 kcal/100 g) energy, 32·21 mg/100 g Fe, 77·51 mg/100 g Ca and 2·59 mg/100 g Zn. The energy density of the optimised novel complementary flour was 1·27 kcal/g which fulfilled the Pan American Health Organization/WHO recommendation (≥ 0·8 kcal/g), protein density was 4·14 g/100 kcal and the Fe density was 8·47 mg/100 kcal, which was 2·12 to 10·59 times higher than the recommended value where the optimal had demonstrated to contribute more than 100 % of the daily energy and protein demand and notably more than 200 % of daily Fe demand at moderate bioavailability (0·8-4 mg/100 kcal). These findings showed that the daily recommended dietary allowance for energy, protein and Fe could be attained by the developed dabi teff-field pea-based optimised novel complementary flour and its contribution to the children's daily energy and nutrients demand met the standard, where the product can be used as food-based nutrition intervention to manage protein-energy malnutrition and Fe deficiency anemia in children sustainably.

Epigenetic and immunological indicators of IPEX disease in subjects with FOXP3 gene mutation.

BACKGROUND: Forkhead box protein 3 (FOXP3) is the master transcription factor in CD4+CD25hiCD127lo regulatory T (Treg) cells. Mutations in FOXP3 result in IPEX (immune dysregulation, polyendocrinopathy, enteropathy, X-linked) syndrome. Clinical presentation of IPEX syndrome is broader than initially described, challenging the understanding of the disease, its evolution, and treatment choice. OBJECTIVE: We sought to study the type and extent of immunologic abnormalities that remain ill-defined in IPEX, across genetic and clinical heterogeneity. METHODS: We performed Treg-cell-specific epigenetic quantification and immunologic characterization of severe "typical" (n = 6) and "atypical" or asymptomatic (n = 9) patients with IPEX. RESULTS: Increased number of cells with Treg-cell-Specific Demethylated Region demethylation in FOXP3 is a consistent feature in patients with IPEX, with (1) highest values in those with typical IPEX, (2) increased values in subjects with pathogenic FOXP3 but still no symptoms, and (3) gradual increase over the course of disease progression. Large-scale profiling using Luminex identified plasma inflammatory signature of macrophage activation and TH2 polarization, with cytokines previously not associated with IPEX pathology, including CCL22, CCL17, CCL15, and IL-13, and the inflammatory markers TNF-α, IL-1A, IL-8, sFasL, and CXCL9. Similarly, both Treg-cell and Teff compartments, studied by Mass Cytometry by Time-Of-Flight, were skewed toward the TH2 compartment, especially in typical IPEX. CONCLUSIONS: Elevated TSDR-demethylated cells, combined with elevation of plasmatic and cellular markers of a polarized type 2 inflammatory immune response, extends our understanding of IPEX diagnosis and heterogeneity.

Impact of Fermentation, Autoclaving and Phytase Treatment on the Antioxidant Properties and Quality of Teff Cookies.

Research background: Teff [Eragrostis tef (Zucc.) Trotter] is an underutilised cereal crop grown mainly in Ethiopia and Eritrea. It is an excellent source of dietary fibre, vitamins, minerals and bioactive compounds. However, it also contains a high amount of phytic acid, which is an antinutrient and reduces the bioavailability of minerals and proteins. To improve the nutritional quality of teff, the phytic acid content should be reduced by an effective dephytinisation method. Experimental approach: In this study, various dephytinisation methods (fermentation, autoclaving and phytase treatment) were used to dephytinise teff flour. Undephytinised and dephytinised teff flour was mixed into wheat flour (0-40 %) to improve the functional properties of cookies. Twenty different cookie formulations were prepared according to 4x5x2 factorial design. The physical, chemical, nutritional and sensory properties of the cookies were investigated. Results and conclusions: Among the dephytinisation methods, fermentation produced the most effective reduction in phytic acid mass fraction (181 mg/100 g), followed by phytase treatment (198 mg/100 g). The protein, fat, Fe and Zn content and antioxidant activity of cookies enriched with dephytinised teff flour were comparable to cookies fortified with undephytinised teff flour. Moreover, the dephytinised teff cookies had lower phytic acid mass fractions. The cookies containing 40 % teff flour had higher antioxidant activity and nutritional quality than the control wheat cookies. The use of dephytinised teff flour reduced the spread ratio and the a* and b* values of cookies compared to undephytinised flour. Cookies containing fermented and phytase-treated teff flour had a harder texture than cookies containing undephytinised flour. In addition, as the amount of teff flour increased, the spread ratio values of cookies gradually incrased while their hardness decreased. Overall acceptability scores of cookies containing 10-20 % teff flour were similar to the control. Novelty and scientific contribution: To the best of our knowledge, this is the first study to determine the quality of cookies containing dephytinised teff flour. The data highlight the potential of dephytinised (especially autoclaved and phytase-treated) teff flour (up to 20 %) as a functional ingredient to enrich the mineral content and antioxidant capacity of foods. Furthermore, this study shows that fermentation, autoclaving and phytase treatment can be used to improve the nutritional quality of grains.

Calcium Determines Lactiplantibacillus plantarum Intraspecies Competitive Fitness.

The importance of individual nutrients for microbial strain robustness and coexistence in habitats containing different members of the same species is not well understood. To address this for Lactiplantibacillus plantarum in food fermentations, we performed comparative genomics and examined the nutritive requirements and competitive fitness for L. plantarum strains B1.1 and B1.3 isolated from a single sample of teff injera fermentation batter. Compared to B1.1 and other L. plantarum strains, B1.3 has a smaller genome, limited biosynthetic capacities, and large mobilome. Despite these differences, B1.3 was equally competitive with B1.1 in a suspension of teff flour. In commercially sourced, nutrient-replete MRS (cMRS) medium, strain B1.3 reached 3-fold-higher numbers than B1.1 within 2 days of passage. Because B1.3 growth and competitive fitness were poor in mMRS medium (here called mMRS), a modified MRS medium lacking beef extract, we used mMRS to identify nutrients needed for robust B1.3 growth. No improvement was observed when mMRS was supplemented with nucleotides, amino acids, vitamins, or monovalent metals. Remarkably, the addition of divalent metal salts increased the growth rate and cell yields of B1.3 in mMRS. Metal requirements were confirmed by inductively coupled plasma mass spectrometry, showing that total B1.3 intracellular metal concentrations were significantly (up to 2.7-fold) reduced compared to B1.1. Supplemental CaCl2 conferred the greatest effect, resulting in equal growth between B1.1 and B1.3 over five successive passages in mMRS. Moreover, calcium supplementation reversed a B1.3 strain-specific, stationary-phase, flocculation phenotype. These findings show how L. plantarum calcium requirements affect competitive fitness at the strain level. IMPORTANCE Ecological theory states that the struggle for existence is stronger between closely related species. Contrary to this assertion, fermented foods frequently sustain conspecific individuals, in spite of their high levels of phylogenetic relatedness. Therefore, we investigated two isolates of Lactiplantibacillus plantarum, B1.1 and B1.3, randomly selected from a single batch of teff injera batter. These strains spanned the known genomic and phenotypic range of the L. plantarum species, and in laboratory culture medium used for strain screening, B1.3 exhibited poor growth and was outcompeted by the more robust strain B1.1. Nonetheless, B1.1 and B1.3 were equally competitive in teff flour. This result shows how L. plantarum has adapted for coexistence in that environment. The capacity for the single macronutrient calcium to restore B1.3 competitive fitness in laboratory culture medium suggests that L. plantarum intraspecies diversity found in food systems is fine-tuned to nutrient requirements at the strain level.

May be adenosine an immuno-quorum-sensing signal?

Quorum sensing indicates a communication process between bacteria based on a coordinate variation in gene expression aimed at coordinating a collective comportment related to the bacterial population density. Increasing pieces of evidence pointed out that a quorum-sensing system can be a regulatory program also used in the immune field to organize the density of the various immune cell populations and to calibrate their responses. In particular, such equilibrium is achieved by the ability of immune cells to perceive the density of their own populations or those of other cells in their environment, through the release of several mediators able to finely shape the cell density via coordinated changes in gene expression and protein signaling. In this regard, adenosine displays the typical characteristics of a mediator involved in the regulation of quorum sensing, thus suggesting a putative role of this nucleoside in shaping the balance between diverse immune cell populations.

Seasonal and diurnal soil respiration dynamics under different land management practices in the sub-tropical highland agroecology of Ethiopia.

The temporal dynamics of soil respiration change in response to different land management practices are not well documented. This study investigated the effects of soil bunds on the monthly and diurnal dynamics of soil respiration rates in the highlands of the Upper Blue Nile basin in Ethiopia. Six plots (with and without soil bunds, three replicates) were used for measurement of seasonal soil respiration, and 18 plots were used for measurement of diurnal soil respiration. We collected seasonal variation data on a monthly basis from September 2020 to August 2021. Diurnal soil respiration data were collected four times daily (5 a.m., 11 a.m., 5 p.m., and 11 p.m.) for 2 weeks from 16 to 29 September 2021. A Wilcoxon signed-rank test showed that seasonal soil respiration rates differed significantly (p < 0.05) between soil bund and control plots in all seasons. In plots with soil bunds, seasonal soil respiration rates were lowest in February (1.89 ± 0.3 µmol CO2 m-2 s-1, mean ± SE) and highest in October (14.54 ± 0.5 µmol CO2 m-2 s-1). The diurnal soil respiration rate was significantly (p < 0.05) higher at 11 a.m. than at other times, and was lowest at 5 a.m. Seasonal variation in soil respiration was influenced by soil temperature negatively and moisture positively. Diurnal soil respiration was significantly affected by soil temperature but not by soil moisture. Further study is required to explore how differences in soil microorganisms between different land management practices affect soil respiration rates.

Teff Grain-Based Functional Food for Prevention of Osteoporosis: Sensory Evaluation and Molecular Docking Approach.

Osteoporosis is a highly prevalent skeletal disorder, which is characterized by compromised bone strength predisposing to an increased risk of fracture. The medical approaches presently followed for the prevention and treatment are associated with several side effects. Thus, it becomes important to design alternatives that are safer, economical, and easy to use. Plants provide us with a beneficial and effective option for such designs. They are rich in nutrients and phytochemicals that can be used to target signalling pathways to prevent the development of disease. For this purpose, we used Ethiopian grain, teff as a preventive strategy for osteoporosis as it has a favourable nutritional profile. In our study, we focussed on the preparation of functional multi-grain flour with Ethiopian grain, teff, and other ingredients that have a positive effect on bone health. A cookie was prepared from the multi mix flour and to analyze its shelf life and acceptance we performed a sensory evaluation where we observed no significant difference in the cookies' characteristics during the period of study. We also performed Molecular Docking of eight flavonoid polyphenols selected from the nutritional profile of the ingredients to understand their binding affinity, interaction with the target, receptor activator of nuclear factor kappa-Β ligand (RANKL), and prophylactic or therapeutic effects in the prevention of osteoporosis. It was found that all 8 flavonoid polyphenols bound with RANKL, at least at one of the crucial binding sites and so can be used for the prevention of osteoporosis.

CD4+ effector T cells accelerate Alzheimer's disease in mice.

BACKGROUND: Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by pathological deposition of misfolded self-protein amyloid beta (Aß) which in kind facilitates tau aggregation and neurodegeneration. Neuroinflammation is accepted as a key disease driver caused by innate microglia activation. Recently, adaptive immune alterations have been uncovered that begin early and persist throughout the disease. How these occur and whether they can be harnessed to halt disease progress is unclear. We propose that self-antigens would induct autoreactive effector T cells (Teffs) that drive pro-inflammatory and neurodestructive immunity leading to cognitive impairments. Here, we investigated the role of effector immunity and how it could affect cellular-level disease pathobiology in an AD animal model. METHODS: In this report, we developed and characterized cloned lines of amyloid beta (Aß) reactive type 1 T helper (Th1) and type 17 Th (Th17) cells to study their role in AD pathogenesis. The cellular phenotype and antigen-specificity of Aß-specific Th1 and Th17 clones were confirmed using flow cytometry, immunoblot staining and Aß T cell epitope loaded haplotype-matched major histocompatibility complex II IAb (MHCII-IAb-KLVFFAEDVGSNKGA) tetramer binding. Aß-Th1 and Aß-Th17 clones were adoptively transferred into APP/PS1 double-transgenic mice expressing chimeric mouse/human amyloid precursor protein and mutant human presenilin 1, and the mice were assessed for memory impairments. Finally, blood, spleen, lymph nodes and brain were harvested for immunological, biochemical, and histological analyses. RESULTS: The propagated Aß-Th1 and Aß-Th17 clones were confirmed stable and long-lived. Treatment of APP/PS1 mice with Aß reactive Teffs accelerated memory impairment and systemic inflammation, increased amyloid burden, elevated microglia activation, and exacerbated neuroinflammation. Both Th1 and Th17 Aß-reactive Teffs progressed AD pathology by downregulating anti-inflammatory and immunosuppressive regulatory T cells (Tregs) as recorded in the periphery and within the central nervous system. CONCLUSIONS: These results underscore an important pathological role for CD4+ Teffs in AD progression. We posit that aberrant disease-associated effector T cell immune responses can be controlled. One solution is by Aß reactive Tregs.

Constipation induced gut microbiota dysbiosis exacerbates experimental autoimmune encephalomyelitis in C57BL/6 mice.

BACKGROUND: Constipation is a common gastrointestinal dysfunction which has a potential impact on people's immune state and their quality of life. Here we investigated the effects of constipation on experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis (MS). METHODS: Constipation was induced by loperamide in female C57BL/6 mice. The alternations of gut microbiota, permeability of intestinal barrier and blood-brain barrier, and histopathology of colon were assessed after constipation induction. EAE was induced in the constipation mice. Fecal microbiota transplantation (FMT) was performed from constipation mice into microbiota-depleted mice. Clinical scores, histopathology of inflammation and demyelination, Treg/Th17 and Treg17/Teff17 imbalance both in the peripheral lymphatic organs and central nervous system, cytokines include TGF-ß, GM-CSF, IL-10, IL-17A, IL-17F, IL-21, IL-22, and IL-23 in serum were assessed in different groups. RESULTS: Compared with the vehicle group, the constipation mice showed gut microbiota dysbiosis, colon inflammation and injury, and increased permeability of intestinal barrier and blood-brain barrier. We found that the clinical and pathological scores of the constipation EAE mice were severer than that of the EAE mice. Compared with the EAE mice, the constipation EAE mice showed reduced percentage of Treg and Treg17 cells, increased percentage of Th17 and Teff17 cells, and decreased ratio of Treg/Th17 and Treg17/Teff17 in the spleen, inguinal lymph nodes, brain, and spinal cord. Moreover, the serum levels of TGF-ß, IL-10, and IL-21 were decreased while the GM-CSF, IL-17A, IL-17F, IL-22, and IL-23 were increased in the constipation EAE mice. In addition, these pathological processes could be transferred via their gut microbiota. CONCLUSIONS: Our results verified that constipation induced gut microbiota dysbiosis exacerbated EAE via aggravating Treg/Th17 and Treg17/Teff17 imbalance and cytokines disturbance in C57BL/6 mice.

Integrated Metabolomics and Proteomics Analyses in the Local Milieu of Islet Allografts in Rejection versus Tolerance.

An understanding of the immune mechanisms that lead to rejection versus tolerance of allogeneic pancreatic islet grafts is of paramount importance, as it facilitates the development of innovative methods to improve the transplant outcome. Here, we used our established intraocular islet transplant model to gain novel insight into changes in the local metabolome and proteome within the islet allograft's immediate microenvironment in association with immune-mediated rejection or tolerance. We performed integrated metabolomics and proteomics analyses in aqueous humor samples representative of the graft's microenvironment under each transplant outcome. The results showed that several free amino acids, small primary amines, and soluble proteins related to the Warburg effect were upregulated or downregulated in association with either outcome. In general, the observed shifts in the local metabolite and protein profiles in association with rejection were consistent with established pro-inflammatory metabolic pathways and those observed in association with tolerance were immune regulatory. Taken together, the current findings further support the potential of metabolic reprogramming of immune cells towards immune regulation through targeted pharmacological and dietary interventions against specific metabolic pathways that promote the Warburg effect to prevent the rejection of transplanted islets and promote their immune tolerance.

Towards coeliac-safe bread.

Gluten-free foods cannot substitute for products made from wheat flour. When wheat products are digested, the remaining peptides can trigger an autoimmune disease in 1% of the North American and European population, called coeliac disease. Because wheat proteins are encoded by a large gene family, it has been impossible to use conventional breeding to select wheat varieties that are coeliac-safe. However, one can test the properties of protein variants by expressing single genes in coeliac-safe cereals like maize. One source of protein that can be considered as coeliac-safe and has bread-making properties is teff (Eragrostis tef), a grain consumed in Ethiopia. Here, we show that teff α-globulin3 (Etglo3) forms storage vacuoles in maize that are morphologically similar to those of wheat. Using transmission electron microscopy, immunogold labelling shows that Etglo3 is almost exclusively deposited in the storage vacuole as electron-dense aggregates. Of maize seed storage proteins, 27-kDa γ-zein is co-deposited with Etglo3. Etglo3 polymerizes via intermolecular disulphide bonds in maize, similar to wheat HMW glutenins under non-reducing conditions. Crossing maize Etglo3 transgenic lines with α-, ß- and γ-zein RNA interference (RNAi) lines reveals that Etglo3 accumulation is only dramatically reduced in γ-zein RNAi background. This suggests that Etglo3 and 27-kDa γ-zein together cause storage vacuole formation and behave similar to the interactions of glutenins and gliadins in wheat. Therefore, expression of teff α-globulins in maize presents a major step in the development of a coeliac-safe grain with bread-making properties.

Emerging patterns of regulatory T cell function in tuberculosis.

Tuberculosis (TB) is one of the top 10 causes of mortality worldwide from a single infectious agent and has significant implications for global health. A major hurdle in the development of effective TB vaccines and therapies is the absence of defined immune-correlates of protection. In this context, the role of regulatory T cells (Treg ), which are essential for maintaining immune homeostasis, is even less understood. This review aims to address this knowledge gap by providing an overview of the emerging patterns of Treg function in TB. Increasing evidence from studies, both in animal models of infection and TB patients, points to the fact the role of Tregs in TB is dependent on disease stage. While Tregs might expand and delay the appearance of protective responses in the early stages of infection, their role in the chronic phase perhaps is to counter-regulate excessive inflammation. New data highlight that this important homeostatic role of Tregs in the chronic phase of TB may be compromised by the expansion of activated human leucocyte antigen D-related (HLA-DR)+ CD4+ suppression-resistant effector T cells. This review provides a comprehensive and critical analysis of the key features of Treg cells in TB; highlights the importance of a balanced immune response as being important in TB and discusses the importance of probing not just Treg frequency but also qualitative aspects of Treg function as part of a comprehensive search for novel TB treatments.

Separation of Partial Discharge Sources Measured in the High-Frequency Range with HFCT Sensors Using PRPD-teff Patterns.

During the last two decades, on-line partial discharge (PD) measurements have been proven as a very efficient test to evaluate the insulation condition of high-voltage (HV) installations in service. Among the different PD-measuring techniques, the non-conventional electromagnetic methods are the most used due to their effectiveness and versatility. However, there are two main difficulties to overcome in on-line PD measurements when these methods are applied: the ambient electric noise and the simultaneous presence of various types of PD or pulse-shaped signals in the HV facility to be evaluated. A practical and effective method is presented to separate and identify PD sources acting simultaneously in HV systems under test. This method enables testers to carry out a first accurate diagnosis of the installation while performing the measurements in situ with non-invasive high-frequency current transformers (HFCT) used as sensors. The data acquisition in real-time reduces the time of postprocessing by an expert. This method was implemented in a Matlab application named PRPD-time tool, which consists of the analysis of the Phase-Resolved Partial Discharge (PRPD) pattern in combination with two types of interactive graphic representations. These graphical depictions are obtained including a feature parameter, effective time (teff), related to the duration of single measured pulses as a third axis incorporated in a classical PRPD representation, named the PRPD-teff pattern. The resulting interactive diagrams are complementary and allow the pulse source separation of pulses and clustering. The effectiveness of the proposed method and the developed Matlab application for separating PD sources is demonstrated with a practical laboratory experiment where various PD sources and pulse-type noise interferences were simultaneously measured.

Teff consumption and anemia in pregnant Ethiopian women: a case-control study.

PURPOSE: Teff, an iron-rich staple grain in Ethiopia, is consumed mainly in the form of teff injera (TI). Studies on the association of TI consumption with anemia are limited. We aimed to determine the association of frequencies of TI consumption with anemia, in Addis Ababa, Ethiopia. METHODS: We conducted a hospital-based case-control study involving 592 pregnant women: 187 anemic cases, and 405 non-anemic controls. TI consumption was assessed by a food frequency questionnaire (FFQ). Multiple logistic regression, adjusted for dietary and non-dietary covariates, was performed to determine the relation of TI consumption to anemia status. RESULTS: We found that a decrease in frequency of TI consumption was significantly associated with an increase in the likelihood of anemia (p-trend = 0.009). Compared with everyday TI consumption, the adjusted odds ratios (AORs) of anemia associated with the other frequencies of teff consumption were 1.50 [95% confidence interval (CI) 0.71, 3.23; p = 0.285] for every other day, 2.13 (95% CI 1.03, 4.41; p = 0.04) for 1-2 times a week, and 3.17 (95% CI 1.62, 6.22; p < 0.001) for once in 2 weeks. CONCLUSIONS: Teff consumption was associated with reduced odds of anemia in pregnant women. Further studies are warranted, including determining the feasibility and effectiveness of TI use for anemia prevention. REGISTRATION: The study was registered as https://clinicaltrials.gov/ct2/show/NCT03251664 .

Extrinsic iron from soil contributes to Hb regeneration of anaemic rats: implications for foods contaminated with soil iron.

Contamination of foods with extrinsic (soil) Fe is common in developing countries. However, the bioavailability of this extrinsic Fe and the extent to which it contributes to Fe nutrition remains unknown. The present study compared the bioavailability of laboratory- and field-threshed teff (Eragrostisis tef (Zucc) Trotter) to evaluate the bioavailablity of extrinsic soil Fe that resulted from the traditional threshing of the staple grain. Using sequential extraction, Fe was fractionated and its solubility was evaluated. The contribution of the additional extrinsic (soil) Fe to the Hb regeneration of Fe-depleted rats was evaluated using a rat Hb depletion-repletion assay. Weanling male Wistar rats (n 24) were fed Fe-deficient diet for 21 d, and were then repleted for 14 d with diets: either laboratory-threshed teff (35 mg Fe/kg; n 8), field-threshed teff (35 mg intrinsic Fe/kg+ 120 mg soil Fe/kg; n 8), or FeSO4 (control; n 8). Fe content of field-threshed teff (29·4 mg/100 g) was four times greater than that of the laboratory-threshed (6·7 mg/100 g) teff (P<0·05). Soil contamination significantly increased the exchangeable, acid-soluble and reducible fractions obtained after sequential extraction. The relative biological value of the field-threshed teff (88 %) was higher than that of the laboratory-threshed (68 %) teff (P<0·05). Soil Fe can contribute to Hb regeneration in Fe-deficient rats. Considering that contamination of foods with soil is common in Ethiopia and other developing countries, it needs to be accounted for in the design and implementation of fortification programmes to prevent excessive intakes. Human studies are needed to confirm the present findings.

Regulatory T cells and IL-10 as modulators of chikungunya disease outcome: a preliminary study.

Regulatory T (Treg) cells hold centre stage in regulating the immune responses in most viral infections. However, their involvement in chikungunya infection is unexplored. In the current study, the frequencies and functionality of peripheral Treg and T effector (Teff) cells were assessed during different phases of chikungunya by flow cytometry and in-vitro cytokine assays. Treg cells were also studied in rheumatoid arthritis (RA) patients, whose symptoms closely mimic chronic chikungunya arthritis patients. Frequency of Treg cells was lower in acute and chronic chikungunya arthritis patients than in recovered individuals and controls, and comparable among recovered individuals and controls. Treg/Teff ratio was lower in acute than in chronic chikungunya arthritis patients, recovered individuals and controls. Higher secretion of CHIKV specific IL-10 was observed in recovered individuals than in acute, chronic chikungunya arthritis patients and controls. Frequencies of Treg and Teff cells were higher and Treg/Teff ratio was lower in RA patients than in chronic chikungunya arthritis patients. The results indicate that reduction of Treg cells was associated with ongoing CHIKV infection and normalization of Treg cells with resolution of disease. Contrasting phenotypic data in RA and chronic chikungunya arthritis suggest an altogether different mechanism of Treg-mediated pathology in both arthritis conditions. Overall, our preliminary study, suggesting an association of peripheral Treg cells and IL-10 with recovery from chikungunya, may provide insight into chikungunya disease prognosis and warrants further study.

The Potential of Fermentation and Contamination of Teff by Soil to Influence Iron Intake and Bioavailability from Injera Flatbread.

The high phytic acid (PA) concentration in the diet based on teff injera is a likely contributing cause of iron deficiency in Ethiopia. We monitored PA during teff injera fermentation in 30 households in Debre Zeyit, Ethiopia and evaluated its influence on iron bioavailability, considering contaminant soil iron in teff flour. After fermentation (48h), mean PA concentration in injera batter decreased from 0.87 to 0.58 g/100 g dm (P < 0.001). Low phytase activity in teff flour (0.44 µmol phosphate/min/g) and a rapid drop in pH, indicated that PA degradation was driven by microbial phytases. The iron concentration in injera batter among the households ranged widely from 14.5-160.4 mg/100 g dm (mean: 34.7 mg/100 g dm) principally due to contamination with soil. Estimated intrinsic iron concentration of teff based on the strong correlation between total iron and aluminium concentrations (P < 0.001; aluminium concentrations in injera batter: 28.7-184.9 mg/100 g dm) was 4.4 mg/100 g dm, indicating that 86-97 % is extrinsic iron from soil. The median daily iron intakes from 3-day weighed food records in 10 young children were 18.9 mg/day including soil iron vs. 4.9 mg/day without soil iron (P < 0.01). The PA:iron molar ratios indicated low iron bioavailability from teff injera, particularly when soil iron was excluded. Traditional fermentation thus has a modest influence on PA levels and more complete degradation is needed to improve iron bioavailability. There is an urgent need to better understand the bioavailability of contamination iron from soil before considering national fortification or biofortification strategies in Ethiopia.

Maternal and cord blood miR-223 expression associates with prenatal tobacco smoke exposure and low regulatory T-cell numbers.

BACKGROUND: There is evidence that microRNAs (miRNAs) are sensitive to environmental stressors, including tobacco smoke. On the other hand, miRNAs are involved in immune regulation, such as regulatory T (Treg) cell differentiation. The aim of the present study was to investigate the association between prenatal tobacco smoke exposure, miRNAs, and Treg cell numbers. METHODS: Within a prospective mother-child study (Lifestyle and Environmental Factors and Their Influence on Newborns Allergy Risk), we analyzed the expression of miR-155 and miR-223 together with Treg cell numbers in maternal blood during pregnancy, as well as in cord blood (n = 441). Tobacco smoke exposure was assessed based on questionnaire answers and maternal urine cotinine levels. Additionally, the concentration of smoking-related volatile organic compounds was measured in dwellings of study participants. RESULTS: Both maternal and cord blood miR-223 expressions were positively correlated with maternal urine cotinine levels. An association was also found between maternal miR-223 expression and indoor concentrations of benzene and toluene. High miR-223 expression was associated with lower Treg cell numbers in maternal and cord blood. Furthermore, children with lower Treg cell numbers at birth had a higher risk of atopic dermatitis during the first 3 years of life. The concentration of the toluene metabolite S-benzylmercapturic acid in maternal urine was associated with decreased cord blood, but not maternal blood, miR-155 expression. A relationship between miR-155 expression and Treg cell numbers was not found. CONCLUSIONS: For the first time, we show that maternal tobacco smoke exposure during pregnancy correlates with the level of miRNA-223 expression in blood, with an effect on children's cord blood Treg cell numbers and subsequent allergy risk.

Peanut oral immunotherapy results in increased antigen-induced regulatory T-cell function and hypomethylation of forkhead box protein 3 (FOXP3).

BACKGROUND: The mechanisms contributing to clinical immune tolerance remain incompletely understood. This study provides evidence for specific immune mechanisms that are associated with a model of operationally defined clinical tolerance. OBJECTIVE: Our overall objective was to study laboratory changes associated with clinical immune tolerance in antigen-induced T cells, basophils, and antibodies in subjects undergoing oral immunotherapy (OIT) for peanut allergy. METHODS: In a phase 1 single-site study, we studied participants (n = 23) undergoing peanut OIT and compared them with age-matched allergic control subjects (n = 20) undergoing standard of care (abstaining from peanut) for 24 months. Participants were operationally defined as clinically immune tolerant (IT) if they had no detectable allergic reactions to a peanut oral food challenge after 3 months of therapy withdrawal (IT, n = 7), whereas those who had an allergic reaction were categorized as nontolerant (NT; n = 13). RESULTS: Antibody and basophil activation measurements did not statistically differentiate between NT versus IT participants. However, T-cell function and demethylation of forkhead box protein 3 (FOXP3) CpG sites in antigen-induced regulatory T cells were significantly different between IT versus NT participants. When IT participants were withdrawn from peanut therapy for an additional 3 months (total of 6 months), only 3 participants remained classified as IT participants, and 4 participants regained sensitivity along with increased methylation of FOXP3 CpG sites in antigen-induced regulatory T cells. CONCLUSION: In summary, modifications at the DNA level of antigen-induced T-cell subsets might be predictive of a state of operationally defined clinical immune tolerance during peanut OIT.