Assessment of peripheral blood lymphocyte subsets in children with iron deficiency anemia

Malnutrition and Allergies: Tipping the Immune Balance towards Health

Malnutrition, which includes macro- and micronutrient deficiencies, is common in individuals with allergic dermatitis, food allergies, rhinitis, and asthma. Prolonged deficiencies of proteins, minerals, and vitamins promote Th2 inflammation, setting the stage for allergic sensitization. Consequently, malnutrition, which includes micronutrient deficiencies, fosters the development of allergies, while an adequate supply of micronutrients promotes immune cells with regulatory and tolerogenic phenotypes. As protein and micronutrient deficiencies mimic an infection, the body's innate response limits access to these nutrients by reducing their dietary absorption. This review highlights our current understanding of the physiological functions of allergenic proteins, iron, and vitamin A, particularly regarding their reduced bioavailability under inflamed conditions, necessitating different dietary approaches to improve their absorption. Additionally, the role of most allergens as nutrient binders and their involvement in nutritional immunity will be briefly summarized. Their ability to bind nutrients and their close association with immune cells can trigger exaggerated immune responses and allergies in individuals with deficiencies. However, in nutrient-rich conditions, these allergens can also provide nutrients to immune cells and promote health.

Absolute and functional iron deficiency: Biomarkers, impact on immune system, and therapy

Iron is essential for numerous physiological processes and its deficiency often leads to anemia. Iron deficiency (ID) is a global problem, primarily affecting reproductive-age women and children, especially in developing countries. Diagnosis uses classical biomarkers like ferritin or transferrin saturation. Recent advancements include using soluble transferrin receptor (sTfR) or hepcidin for improved detection and classification of absolute and functional iron deficiencies, though mostly used in research. ID without anemia may present symptoms like asthenia and fatigue, even without relevant clinical consequences. ID impacts not only red-blood cells but also immune system cells, highlighting its importance in global health and immune-related comorbidities. Managing ID, requires addressing its cause and selecting appropriate iron supplementation. Various improved oral and intravenous products are available, but further research is needed to refine treatment strategies. This review updates on absolute and functional iron deficiencies, their relationships with the immune system and advancements in diagnosis and therapies.

Iron deficiency in children with a focus on inflammatory conditions

Iron deficiency (ID) tends to be overlooked compared with anemia. However, its prevalence is estimated to be twice as high as that of ID anemia, and ID without anemia can be accompanied by clinical and functional impairments. The symptoms of ID are nonspecific, such as fatigue and lethargy, but can lead to neurodevelopmental disorders in children, restless legs syndrome, and recurrent infections due to immune system dysregulation. In particular, the risk of ID is high in the context of chronic inflammatory diseases (CIDs) due to the reaction of various cytokines and the resulting increase in hepcidin levels; ID further exacerbates these diseases and increases mortality. Therefore, the diagnosis of ID should not be overlooked through ID screening especially in high-risk groups. Ferritin and transferrin saturation levels are the primary laboratory parameters used to diagnose ID. However, as ferritin levels respond to inflammation, the diagnostic criteria differ among guidelines. Therefore, new tools and criteria for accurately diagnosing ID should be developed. Treatment can be initiated only with an accurate diagnosis. Oral iron is typically the first-line treatment for ID; however, the efficacy and safety of intravenous iron have recently been recognized. Symptoms improve quickly after treatment, and the prognosis of accompanying diseases can also be improved. This review highlights the need to improve global awareness of ID diagnosis and treatment, even in the absence of anemia, to improve the quality of life of affected children, especially those with CIDs.

PD-1 and LAG-3 positive T cells are related with the prognosis of patients with chronic kidney disease

OBJECTIVE

Our objective was to study the frequency of circulating LAG-3+ and PD-1+ T cells in chronic kidney disease (CKD) patients and their correlation with cytokines and patient prognosis.

METHODS

A total of 83 patients with CKD between June 2020 and June 2022 were enrolled. We measured serum levels of IL-6, CRP, IL-1β, and TNF-α by ELISA. The frequency of PD-1+ and LAG-3+ T cells was measured using flow cytometry. All patients were followed up for 1 year, and the occurrence of any of the following conditions during the follow-up period was considered as major adverse cardiac events (MACE) indicating poor prognosis.

RESULTS

The frequencies of LAG-3+PD-1+, LAG-3+ and PD-1+ cells were significantly increased in CKD group compared to healthy volunteers. Additionally, CKD patients had remarkably enhanced levels of cytokines. Compared to the non-MACE group, MACE group had significantly higher frequencies of LAG-3PD-1, LAG-3 and PD-1 expression on CD8 and CD4. Positive correlations were observed between IL-1β, IL-6 and frequencies of PD-1+LAG-3+. CD4+LAG-3+PD-1+ frequency displayed the highest diagnostic value for CKD patients with MACE. Moreover, CD8+LAG-3+, CD4+LAG-3+PD-1+, CD4+PD-1+, IL-1β and IL-6 were identified as risk factors for the occurrence of MACE in patients with CKD.

CONCLUSION

In summary, the present research showed that the frequencies of LAG-3+ and PD-1+ T cells were remarkably enhanced in CKD patients. These findings offer novel insights and potential therapeutic targets for the management of CKD.

The roles of essential trace elements in T cell biology

T cells are crucial for adaptive immunity to regulate proper immune response and immune homeostasis. T cell development occurs in the thymus and mainly differentiates into CD4+ and CD8+ T cell subsets. Upon stimulation, naive T cells differentiate into distinct CD4+ helper and CD8+ cytotoxic T cells, which mediate immunity homeostasis and defend against pathogens or tumours. Trace elements are minimal yet essential components of human body that cannot be overlooked, and they participate in enzyme activation, DNA synthesis, antioxidant defence, hormone production, etc. Moreover, trace elements are particularly involved in immune regulations. Here, we have summarized the roles of eight essential trace elements (iron, zinc, selenium, copper, iodine, chromium, molybdenum, cobalt) in T cell development, activation and differentiation, and immune response, which provides significant insights into developing novel approaches to modulate immunoregulation and immunotherapy.

Effects of metformin therapy on HMGB1 levels in rheumatoid arthritis patients

OBJECTIVE

The traditional treatment of rheumatoid arthritis (RA) has some side effects. We aimed to explore the effect of metformin treatment on the expression of HMGB1, cytokines, T cell subtypes and the clinical outcomes in RA patients.

METHODS

The present prospective cohort study recruited 124 RA patients (metformin group) who were treated with metformin and conventional therapy (methotrexate, hydroxychloroquine sulfate and sulfasalazine) and 98 RA patients (conventional therapy group) who were only treated with conventional therapy. All subjects were admitted from December 2018 to December 2021 and continuous medication for 90 days. The serum high mobility group box 1 (HMGB1), tumor necrosis factor α (TNF-α), interleukin (IL)-6, IL-1β and C-reactive protein (CRP) levels were measured by enzyme-linked immunosorbent assay (ELISA). Flow cytometric were used to analyze the expression of CD4+ and CD8+. Demographic and clinical statistics including age, body mass index (BMI), sex, course of disease, erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), visual analogue score (VAS)and disease activity score (DAS)-28 were collected.

RESULTS

The serum levels of HMGB1, CRP, IL-6, CD4+ expression and CD4+/CD8+ ratio were significantly increased in patients with DAS-28 score ≥ 2.6. The serum HMGB1 and cytokines levels of metformin group declined more quickly during the study time. Pearson's analysis supported that a positive correlation existed between the HMGB1 and IL-6, TNF-α, CRP, CD4+, CD4+/CD8+ ratio, and VAS scores. HMGB1 could be a potential diagnostic biomarker for RA patients in active phase. Serum HMGB1 (95% CI 1.133-1.397, P < 0.001) was a factor associated with active RA.

CONCLUSION

The serum HMGB1 levels were significantly increased in RA patients in active phase. The serum levels of HMGB1 and inflammatory factors and VAS scores were decreased gradually with metformin treatment. HMGB1 might act as a novel therapeutic target for RA.

Association of the HALP Score with Dyslipidemia: A Large, Nationwide Retrospective Study

Background and Objectives: Dyslipidemia is a major risk factor for cardiovascular disease (CVD). The identification of new biomarkers that may enhance the risk assessment of lipid abnormalities is a promising approach in improving risk prediction of CVD. There is no information on the association of the hemoglobin, albumin, lymphocyte, and platelet (HALP) score with dyslipidemia. The aim of this study was to investigate the clinical utility of the HALP score in light of dyslipidemia. Materials and Methods: A retrospective analysis of 7192 subjects was initiated to assess the association between the HALP score and disturbed lipid markers. Medians were compared by Mann-Whitney U or Kruskal-Wallis tests and the diagnostic performance and risk assessment were calculated. Results: Median HALP score among all subjects was 53.3, with varying values between males and females. Notably, median HALP was significantly elevated in all forms of dyslipidemia and among males and females irrespective of age. The odds of having elevated HALP score values were significantly higher in all lipid abnormalities. Moreover, HALP score was significantly yet weakly correlated with lipid markers, while the highest diagnostic accuracy of the HALP score was observed with an elevated ratio of total cholesterol to high-density lipoprotein (TC/HDL) (area under the curve, AUC = 0.6411, p < 0.0001). The decision curve analysis (DCA) showed that the HALP score can reliably predict the presence of dyslipidemia. Conclusions: This study demonstrates that the HALP score is a novel, cost-effective index that is associated with a disturbed lipid profile. Further investigation of the nature of this association is needed.

Impact of low serum iron on treatment outcome of PD-1 inhibitors in advanced gastric cancer

BACKGROUND

The aim of this study was to investigate the influence of serum iron levels in advanced gastric cancer (GC) patients treated with programmed cell death protein-1 (PD-1) inhibitors.

METHODS

We retrospectively reviewed 149 GC patients who were treated with PD-1 inhibitors at our center. Clinicopathological characteristics, laboratory data, and clinical outcomes were analyzed.

RESULTS

Multivariate analysis showed that Eastern Cooperative Oncology Group performance status (ECOG PS), histological subtype, and baseline serum iron levels were independent prognostic factors for overall survival (OS), while ECOG PS, multiple metastatic sites, and baseline serum iron levels were independent prognostic factors for progression-free survival (PFS). Patients with baseline low serum iron levels (LSI) had a significantly shorter median OS and PFS compared to patients with normal serum iron levels (NSI) (Median OS: 7 vs. 14 months, p = 0.001; median PFS: 3 vs. 5 months, p = 0.005). Patients with baseline LSI had a disease control rate (DCR) of 58.3% at 2 months after PD-1 inhibitor initiation (M2), compared to 81.1% in patients with NSI (p = 0.005). Patients with baseline LSI had a DCR of 43.8% at 4 months, compared to 64.2% in patients with NSI (p = 0.017).

CONCLUSIONS

LSI was associated with worse OS, PFS, and DCR in GC patients treated with PD-1 inhibitors and might be a quick and efficient biomarker to predict the efficacy of PD-1 inhibitors.

Nutritional Behavior in European Countries during COVID-19 Pandemic-A Review

COVID-19 is highly linked with hyperinflammation and dysfunction of the immune cells. Studies have shown that adequate nutrition, a modifiable factor affecting immunity and limiting systemic inflammation, may play an adjunct role in combating the negative consequences of SARS-CoV-2 infection. Due to the global lockdown conditions, the COVID-19 pandemic has contributed, among others, to restrictions on fresh food availability and changes in lifestyle and eating behaviors. The aim of this paper was to review the data regarding eating habits in European countries within the general population of adults and some specific subpopulations, including obese, diabetic, and psychiatric patients, during the COVID-19 pandemic. The PubMed database and the official websites of medical organizations and associations were searched for the phrases "COVID" and "eating habits". Papers regarding the pediatric population, non-European countries, presenting aggregated data from different countries worldwide, and reviews were excluded. During the COVID-19 pandemic, unhealthy lifestyles and eating behaviors were commonly reported. These included increased snacking, intake of caloric foods, such as sweets, pastries, and beverages, and a decline in physical activity. Data suggest that poor eating habits that create a positive energy balance have persisted over time as an additional post-COVID negative consequence.

Predictive association of gut microbiome and NLR in anemic low middle-income population of Odisha- a cross-sectional study

Background

Iron is abundant on earth but not readily available for colonizing bacteria due to its low solubility in the human body. Hosts and microbiota compete fiercely for iron. <15% Supplemented Iron is absorbed in the small bowel, and the remaining iron is a source of dysbiosis. The gut microbiome signatures to the level of predicting anemia among low-middle-income populations are unknown. The present study was conducted to identify gut microbiome signatures that have predictive potential in association with Neutrophil to lymphocytes ratio (NLR) and Mean corpuscular volume (MCV) in anemia.

Methods

One hundred and four participants between 10 and 70 years were recruited from Odisha's Low Middle-Income (LMI) rural population. Hematological parameters such as Hemoglobin (HGB), NLR, and MCV were measured, and NLR was categorized using percentiles. The microbiome signatures were analyzed from 61 anemic and 43 non-anemic participants using 16 s rRNA sequencing, followed by the Bioinformatics analysis performed to identify the diversity, correlations, and indicator species. The Multi-Layered Perceptron Neural Network (MLPNN) model were applied to predict anemia.

Results

Significant microbiome diversity among anemic participants was observed between the lower, middle, and upper Quartile NLR groups. For anemic participants with NLR in the lower quartile, alpha indices indicated bacterial overgrowth, and consistently, we identified R. faecis and B. uniformis were predominating. Using ROC analysis, R. faecis had better distinction (AUC = 0.803) to predict anemia with lower NLR. In contrast, E. biforme and H. parainfluenzae were indicators of the NLR in the middle and upper quartile, respectively. While in Non-anemic participants with low MCV, the bacterial alteration was inversely related to gender. Furthermore, our Multi-Layered Perceptron Neural Network (MLPNN) models also provided 89% accuracy in predicting Anemic or Non-Anemic from the top 20 OTUs, HGB level, NLR, MCV, and indicator species.

Conclusion

These findings strongly associate anemic hematological parameters and microbiome. Such predictive association between the gut microbiome and NLR could be further evaluated and utilized to design precision nutrition models and to predict Iron supplementation and dietary intervention responses in both community and clinical settings.

Risk factors of nosocomial infection in patients underwent artificial liver support system: a retrospective case-control study

BACKGROUND

Although nosocomial infection is one of the most discussed problems in patients undergoing artificial liver support system (ALSS) treatment, only few solutions have been proposed so far. This study aimed to explore the risk factors of nosocomial infection in patients treated with ALSS in order to aid in the development of future preventive measures.

METHODS

This retrospective case-control study included patients treated with ALSS at the Department of Infectious Diseases, First Affiliated Hospital of xxx Medical University between January 2016 and December 2021.

RESULTS

One hundred seventy-four patients were included. There were 57 patients in the nosocomial infection group and 117 patients in the non-nosocomial infection group, of them 127 males (72.99%) and 47 females (27.01%) with an average age of 48.15 ± 14.19 years old. Multivariate logistic regression analysis revealed that total bilirubin [odds ratio (OR) = 1.004; 95% confidence interval (CI), 1.001-1.007; P  = 0.020], number of invasive procedures (OR = 2.161; 95% CI, 1.500-3.313; P  < 0.001), blood transfusion (OR = 2.526; 95% CI, 1.312-4.864; P  = 0.006) were independent risk factors and haemoglobin (Hb) (OR = 0.973; 95% CI, 0.953-0.994; P  = 0.011) was a protective factor for nosocomial infection in patients treated with ALSS.

CONCLUSION

The total bilirubin, transfusion of blood products and higher number of invasive operations were independent risk factors for nosocomial infection in patients treated with ALSS, while higher Hb was a protective factor.

Iron-Deficiency in Atopic Diseases: Innate Immune Priming by Allergens and Siderophores

Although iron is one of the most abundant elements on earth, about a third of the world's population are affected by iron deficiency. Main drivers of iron deficiency are beside the chronic lack of dietary iron, a hampered uptake machinery as a result of immune activation. Macrophages are the principal cells distributing iron in the human body with their iron restriction skewing these cells to a more pro-inflammatory state. Consequently, iron deficiency has a pronounced impact on immune cells, favoring Th2-cell survival, immunoglobulin class switching and primes mast cells for degranulation. Iron deficiency during pregnancy increases the risk of atopic diseases in children, while both children and adults with allergy are more likely to have anemia. In contrast, an improved iron status seems to protect against allergy development. Here, the most important interconnections between iron metabolism and allergies, the effect of iron deprivation on distinct immune cell types, as well as the pathophysiology in atopic diseases are summarized. Although the main focus will be humans, we also compare them with innate defense and iron sequestration strategies of microbes, given, particularly, attention to catechol-siderophores. Similarly, the defense and nutritional strategies in plants with their inducible systemic acquired resistance by salicylic acid, which further leads to synthesis of flavonoids as well as pathogenesis-related proteins, will be elaborated as both are very important for understanding the etiology of allergic diseases. Many allergens, such as lipocalins and the pathogenesis-related proteins, are able to bind iron and either deprive or supply iron to immune cells. Thus, a locally induced iron deficiency will result in immune activation and allergic sensitization. However, the same proteins such as the whey protein beta-lactoglobulin can also transport this precious micronutrient to the host immune cells (holoBLG) and hinder their activation, promoting tolerance and protecting against allergy. Since 2019, several clinical trials have also been conducted in allergic subjects using holoBLG as a food for special medical purposes, leading to a reduction in the allergic symptom burden. Supplementation with nutrient-carrying lipocalin proteins can circumvent the mucosal block and nourish selectively immune cells, therefore representing a new dietary and causative approach to compensate for functional iron deficiency in allergy sufferers.

Association of Abnormal Iron Status with the Occurrence and Prognosis of Peritoneal Dialysis-Related Peritonitis: A Longitudinal Data-Based 10-Year Retrospective Study

This retrospective study investigated the effect of iron status on peritonitis by analyzing longitudinal iron parameters in peritoneal dialysis (PD) patients. Patients who received PD at our center from 1 January 2006 to 31 December 2015 were included and followed up until 31 December 2017. According to the joint quartiles of baseline transferrin saturation and ferritin, iron status was categorized as reference iron status (RIS), absolute iron deficiency (AID), functional iron deficiency (FID), and high iron status (HIS). Generalized estimating equations and Cox regression models with time-dependent covariates were used. A total of 1258 PD patients were included; 752 (59.8%) were male, with a mean (±standard deviation) age of 47.4 (±14.9) years. During a median follow-up period of 35.5 (interquartile range, 18.4–60.0) months, 450 (34.3%) patients had 650 episodes of peritonitis. By analyzing longitudinal data, patients with AID were independently positively associated with the occurrence (adjusted odds ratio (AOR) = 1.45) and treatment failure of peritonitis (adjusted hazard ratio (AHR) = 1.85). Patients with HIS were positively associated with the treatment failure of peritonitis (AHR = 2.70). Longitudinal AID and HIS were associated with the episodes and poor prognosis of peritonitis. Active clinical monitoring and correction of iron imbalance in patients with PD are needed.

A Bioinformatics-Assisted Review on Iron Metabolism and Immune System to Identify Potential Biomarkers of Exercise Stress-Induced Immunosuppression

The immune function is closely related to iron (Fe) homeostasis and allostasis. The aim of this bioinformatics-assisted review was twofold; (i) to update the current knowledge of Fe metabolism and its relationship to the immune system, and (ii) to perform a prediction analysis of regulatory network hubs that might serve as potential biomarkers during stress-induced immunosuppression. Several literature and bioinformatics databases/repositories were utilized to review Fe metabolism and complement the molecular description of prioritized proteins. The Search Tool for the Retrieval of Interacting Genes (STRING) was used to build a protein-protein interactions network for subsequent network topology analysis. Importantly, Fe is a sensitive double-edged sword where two extremes of its nutritional status may have harmful effects on innate and adaptive immunity. We identified clearly connected important hubs that belong to two clusters: (i) presentation of peptide antigens to the immune system with the involvement of redox reactions of Fe, heme, and Fe trafficking/transport; and (ii) ubiquitination, endocytosis, and degradation processes of proteins related to Fe metabolism in immune cells (e.g., macrophages). The identified potential biomarkers were in agreement with the current experimental evidence, are included in several immunological/biomarkers databases, and/or are emerging genetic markers for different stressful conditions. Although further validation is warranted, this hybrid method (human-machine collaboration) to extract meaningful biological applications using available data in literature and bioinformatics tools should be highlighted.

Effects of Iron Deficiency and Its Indicators on Lymphocyte Subsets: A Study at King Fahd Hospital of the University, Saudi Arabia

Background

Iron deficiency plays an important role in our body’s immunity. Several studies have shown that it is frequently associated with infections.

Objective

This study aimed to discover the effect of iron deficiency on immunity by demonstrating changes occurring in lymphocyte subsets among patients with an established diagnosis of iron deficiency.

Methods

A total of 64 iron-deficient patients and 19 healthy controls were included. Complete blood counts, serum iron, ferritin, and total iron-binding capacity were assessed. Lymphocyte subsets were evaluated by flow cytometry.

Results

Among iron-deficient patients, the anemic ones (Hb ≤11 g/dL) showed significantly lower absolute lymphocyte counts (p=0.013), lower relative and absolute NK-cell counts (p=0.025 and p=0.003, respectively), higher relative T-cell and CD4⁺-cell counts (p=0.026 and p=0.002, respectively). B cells and CD8⁺ T cells were not affected by any iron-deficiency indicators. Iron-deficient anemia patients showed a three- to fourfold increase in risk of having recurrent infections.

Conclusion

Iron deficiency has an obvious effect on lymphocyte subsets. Changes in lymphocyte subsets started mainly in response to decreased hemoglobin, rather than decreased ferritin and/or iron. Synchronously decreased hemoglobin and increased total iron-binding capacity led to absolute decreases in total lymphocytes, mainly NK cells, and relative increases in T cells, mainly the helper ones. Monitoring changes in lymphocyte subsets may be helpful in identifying patients at risk of recurrent infections.

Fermented goat's milk modulates immune response during iron deficiency anemia recovery

BACKGROUND

Iron deficiency and iron overload can affect the normal functioning of the innate and adaptive immune responses. Fermented milk products may enhance immune functions, but little is known about the effect of fermented milks on modulation of the immune response during iron deficiency anemia and recovery with normal or high dietary iron intake. Eighty male Wistar rats were randomly assigned to a control group fed a standard diet or to an anemic group fed a diet deficit in iron. Control and anemic groups were fed for 30 days with diets based on a fermented goat's or cow's milk product, with normal iron content or iron overload.

RESULTS

In general, during anemia recovery lectin and alternative complement pathway activity and lactoferrin decreased, because it improves iron homeostasis, which is critically important in immune system functions. Fermented goat's milk diet enhanced immune function during iron deficiency recovery, suppressed oxidant-induced eotaxin and fractalkine expression due to the concurrent reduction of free radical production and pro-inflammatory cytokines, and decreased monocyte chemoattractant protein-1 and monocyte migration and adhesion. The increase in interferon-γ can confer immunological colonization of gut microbiota and downregulate inflammation.

CONCLUSION

Fermented goat's milk consumption enhances immune function, modifying complement pathway activity and decreasing pro-inflammatory cytokines as well as lactoferrin concentration, due to the improvement of iron homeostasis, which is critically important in the normal function of the immune system. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Prevalence of anaemia and associated factors among people with pulmonary tuberculosis in Uganda

Anaemia predicts delayed sputum conversion and mortality in tuberculosis (TB). We determined the prevalence and factors associated with anaemia among people with TB at the National Tuberculosis Treatment Centre in Uganda. People with bacteriologically confirmed TB were consecutively enrolled in a cross-sectional study between August 2017 and March 2018. Blood samples were tested for a full blood hemogram, HIV infection, and CD4+ and CD8+ T-cell counts. Anaemia was defined as a haemoglobin level of <13.0 grams per decilitre (g/dl) for males and <12.0 g/dl for females. Of 358 participants, 210 (58.7%, 95% confidence interval (CI) 53.4-63.8) had anaemia. Anaemia was associated with night sweats, a longer duration of fever, low body mass index (BMI), hyperthermia, high sputum bacillary loads, HIV co-infection, and low CD4 and CD8 counts at bivariate analysis. Factors associated with anaemia at multivariable analysis were low BMI (odds ratio (OR) 2.93, 95% CI 1.70-5.05, P < 0.001), low CD4:CD8 ratio (OR 2.54, 95% CI 1.07-6.04, P = 0.035) and microcytosis (OR 4.23, 95% CI 2.17-8.25, P < 0.001). Anaemia may be associated with the features of severe TB disease and should be considered in TB severity scores.

Potent but transient immunosuppression of T-cells is a general feature of CD71+ erythroid cells

CD71+ erythroid cells (CECs) have been recently recognized in both neonates and cancer patients as potent immunoregulatory cells. Here, we show that in mice early-stage CECs expand in anemia, have high levels of arginase 2 (ARG2) and reactive oxygen species (ROS). In the spleens of anemic mice, CECs expansion-induced L-arginine depletion suppresses T-cell responses. In humans with anemia, CECs expand and express ARG1 and ARG2 that suppress T-cells IFN-γ production. Moreover, bone marrow CECs from healthy human donors suppress T-cells proliferation. CECs differentiated from peripheral blood mononuclear cells potently suppress T-cell activation, proliferation, and IFN-γ production in an ARG- and ROS-dependent manner. These effects are the most prominent for early-stage CECs (CD71highCD235adim cells). The suppressive properties disappear during erythroid differentiation as more differentiated CECs and mature erythrocytes lack significant immunoregulatory properties. Our studies provide a novel insight into the role of CECs in the immune response regulation.

Bacterial Siderophores and Their Potential Applications: A Review

The bacterial infection is one of the major health issues throughout the world. To protect humans from the infection and infectious agents, it is important to understand the mechanism of interaction of pathogens along with their susceptible hosts. This will help us to develop a novel strategy for designing effective new drugs or vaccines. As iron is an essential metal ion required for all the living systems for their growth, as well, it is needed by pathogenic bacterial cells for their growth and development inside host tissues. To get iron from the host tissues, microbes developed an iron-chelating system called siderophore and also corresponding receptors. Siderophores are low molecular weight organic complex produced by different strains of bacteria for the procurement of iron from the environment or host body under the iron deficient-conditions. Mostly in the environment at physiological pH, the iron is present in the ferric ionic form (Fe3+), which is water- insoluble and thus inaccessible for them. Such a condition promotes the generation of siderophores. These siderophores have been used in different areas such as agriculture, treatment of diseases, culture the unculturable strains of bacteria, promotion of plant growth, controlling phytopathogens, detoxification of heavy metal contamination, etc. In the medical field, siderophores can be used as "Trojan Horse Strategy", which forms a complex with antibiotics and also delivers these antibiotics to the desired locations, especially in antibiotic-resistant bacteria. The promising application of siderophore-based use of antibiotics for the management of bacterial resistance can be strategies to be used.

The critical roles of iron during the journey from fetus to adolescent: Developmental aspects of iron homeostasis

Iron is indispensable for human life. However, it is also potentially toxic, since it catalyzes the formation of harmful oxidative radicals in unbound form and may facilitate pathogen growth. Therefore, iron homeostasis needs to be tightly regulated. Rapid growth and development require large amounts of iron, while (especially young) children are vulnerable to infections with iron-dependent pathogens due to an immature immune system. Moreover, unbalanced iron status early in life may have effects on the nervous system, immune system and gut microbiota that persist into adulthood. In this narrative review, we assess the critical roles of iron for growth and development and elaborate how the body adapts to physiologically high iron demands during the journey from fetus to adolescent. As a first step towards the development of clinical guidelines for the management of iron disorders in children, we summarize the unmet needs regarding the developmental aspects of iron homeostasis.

Ironing out mechanisms of iron homeostasis and disorders of iron deficiency

Iron plays an important role in mammalian physiological processes. It is a critical component for the function of many proteins, including enzymes that require heme and iron-sulfur clusters. However, excess iron is also detrimental because of its ability to catalyze the formation of reactive oxygen species. As a result, cellular and systemic iron levels are tightly regulated to prevent oxidative damage. Iron deficiency can lead to a number of pathological conditions, the most prominent being anemia. Iron deficiency should be corrected to improve adult patients' symptoms and to facilitate normal growth during fetal development and childhood. However, inappropriate use of intravenous iron in chronic conditions, such as cancer and heart failure, in the absence of clear iron deficiency can lead to unwanted side effects. Thus, this form of therapy should be reserved for certain patients who cannot tolerate oral iron and need rapid iron replenishment. Here, we will review cellular and systemic iron homeostasis and will discuss complications of iron deficiency.

An Evaluation of the Efficacy, Safety, and Tolerability of Abhraloha Compared With Oral Ferrous Ascorbate on Iron Deficiency Anemia in Women: A Randomized Controlled, Parallel-Group, Assessor-Blind Clinical Trial

Background and objective Iron deficiency anemia (IDA) is a common condition in women for which ferrous ascorbate (FA) is often prescribed, which can lead to multiple side effects. Abhraloha is an Ayurvedic medicine that has been used for decades in India to treat IDA. In this study, we aimed to evaluate the efficacy and safety of Abhraloha with regard to change in hemoglobin (Hb) levels as compared to the standard treatment using FA in participants with IDA. Materials and methods We conducted a single-center, pragmatic, prospective, randomized, active-controlled, two-arm, parallel-group, assessor-blind study to evaluate the efficacy and safety of Abhraloha with regard to change in Hb levels as compared to the standard treatment using FA in participants suffering from IDA. The eligible participants were randomized and were advised to take either Abhraloha (two tablets twice a day) or FA (one tablet twice a day) for eight weeks; they were asked to follow up after 14 days for re-evaluation. On visit 1 and during the study period, the physician assessed the participants on the Pandurog scale and subjective variables. Descriptive statistics were used with unpaired T-test/Mann-Whitney U test for comparison between the groups. The Wilcoxon signed-rank test was used for within-group analysis, and the chi-square test/Fisher's exact test was employed for categorical data. Results Based on our findings, Abhraloha tablets significantly increased all the variables including the Pandurog scale after eight weeks of treatment. Abhraloha reduced total iron-binding capacity (TIBC) and peripheral smear lymphocyte (PSL), which is consistent with an improvement in IDA. There was a statistically significant increase in Hb, red blood cell (RBC) count, packed cell volume (PCV), mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) in the Abhraloha group as compared with the FA group at eight weeks. The Abhraloha group also exhibited a statistically significant improvement in all the subjective variables. Abhraloha was found to be safe and well-tolerated among the participants. Conclusions Abhraloha possesses hematinic activity and it improves all the blood indices. It is associated with significantly fewer adverse effects compared to oral iron therapy, which proves that it can be safely used for the treatment of IDA.

Trace Elements as Immunoregulators in SARS-CoV-2 and Other Viral Infections

Nutritional deficiency is associated with impaired immunity and increased susceptibility to infections. The complex interactions of trace elements with the macromolecules trigger the effective immune response against the viral diseases. The outcome of various viral infections along with susceptibility is affected by trace elements such as zinc, selenium, iron, copper, etc. due to their immuno-modulatory effects. Available electronic databases have been comprehensively searched for articles published with full text available and with the key words “Trace elements”, “COVID-19”, “Viral Infections” and “Immune Response” (i.e. separately Zn, Se, Fe, Cu, Mn, Mo, Cr, Li, Ni, Co) appearing in the title and abstract. On the basis of available articles we have explored the role of trace elements in viral infections with special reference to COVID-19 and their interactions with the immune system. Zinc, selenium and other trace elements are vital to triggerT_H1 cells and cytokine-mediated immune response for substantial production of proinflammatory cytokines. The antiviral activity of some trace elements is attributed to their inhibitory effect on viral entry, replication and other downstream processes. Trace elements having antioxidants activity not only regulate host immune responses, but also modify the viral genome. Adequate dietary intake of trace elements is essential for activation, development, differentiation and numerous functions.

Anemia as a risk factor for tuberculosis: a systematic review and meta-analysis

BACKGROUND

Tuberculosis is a major public health problem caused by Mycobacterium tuberculosis, occurring predominantly in population with low socioeconomic status. It is the second most common cause of death from infectious diseases. Tuberculosis becomes a double burden among anemic patients. Anemia increases an individual's susceptibility to infectious diseases including tuberculosis by reducing the immunity level. Therefore, the purpose of this study was to determine whether anemia is a risk factor for tuberculosis.

METHOD

Relevant published articles were searched in electronic databases like PubMed, Google Scholar, EMBASE, and Cochrane Library using the following MeSH terms: risk factor, predictors, tuberculosis, TB, Anaemia, Anemia, hemoglobin, Hgb, and Hb. Articles written in the English, observational studies conducted on the incidence/prevalence of tuberculosis among anemic patients, or papers examined anemia as risk factors for tuberculosis were included. From those studies meeting eligibility criteria, the first author's name, publication year, study area, sample size and age of participants, study design, and effect measure of anemia for tuberculosis were extracted. The data were entered using Microsoft Excel and exported to Stata version 11 for analysis. The random-effects model was applied to estimate the pooled OR and HR, and 95% CI. The sources of heterogeneity were tested by Cochrane I-squared statistics. The publication bias was assessed using Egger's test statistics.

RESULTS

A total of 17 articles with a 215,294 study participants were included in the analysis. The odd of tuberculosis among anemic patients was 3.56 (95% CI 2.53-5.01) times higher than non-anemic patients. The cohort studies showed that the HR of tuberculosis was 2.01 (95% CI 1.70-2.37) times higher among anemic patients than non-anemic patients. The hazard of tuberculosis also increased with anemia severity (HR 1.37 (95% CI 0.92-2.05), 2.08 (95% CI 1.14-3.79), and 2.66 (95% CI 1.71-4.13) for mild, moderate, and severe anemia, respectively).

CONCLUSION

According to the current systematic review and meta-analysis, we can conclude that anemia was a risk factor for tuberculosis. Therefore, anemia screening, early diagnose, and treatment should be provoked in the community to reduce the burden of tuberculosis.

An evaluation of ferric derisomaltose as a treatment for anemia

Introduction: Originally approved in Europe in 2009, ferric derisomaltose is the most recently authorized intravenous iron compound in the United States of America (2020). Ferric derisomaltose given as a rapid high-dose infusion can allow complete iron repletion in a single dose and it is now widely used in the treatment of iron deficiency. Areas covered: The chemistry, pharmacodynamics and pharmacokinetics of ferric derisomaltose are reviewed. Results from phase II, III and IV trials regarding efficacy and safety are presented. Mechanisms behind minor infusion reactions, hypersensitivity and hypophosphatemia are discussed. The economic impact of ferric derisomaltose use is presented. Data pertaining to the use of ferric derisomaltose in iron deficiency anemia, chronic kidney disease, inflammatory bowel disease, chronic heart failure, perioperative care and other patient groups are comprehensively covered. Expert opinion: Ferric derisomaltose is an effective intravenous iron formulation with a good safety profile, providing rapid, cost-effective iron repletion. Ferric derisomaltose releases low quantities of labile iron relative to older compounds. Anaphylaxis is extremely rare, and 'Fishbane' reactions are uncommon. Hypophosphatemia following ferric derisomaltose administration is infrequent in comparison to other intravenous irons such as ferric carboxymaltose. The scope of ferric derisomaltose use is growing with increasing research in these areas.

Improving the safety of intravenous iron treatments for patients with chronic kidney disease

Introduction: Iron-deficiency anemia in chronic kidney disease (CKD) is common and has prognostic, financial, and quality of life implications. Intravenous (IV) iron is a key intervention for optimal management, however, ongoing safety concerns exist. Area covered: The potential side effects associated with IV iron use are addressed as we review the most recent studies. Hypersensitivity reactions and true anaphylaxis are indeed rare with a greater understanding of the nature of labile iron and 'Fishbane' reactions. Hypophosphatemia appears commoner with certain IV iron preparations, however its significance in CKD requires exploration. The long-standing questions regarding oxidative stress and the potential susceptibility to infections and worsening cardiovascular morbidity are discussed. Iron overload secondary to repeat IV iron infusions is plausible, however, a number of guidelines limit and strictly guide prescription. Expert opinion: The past decade has improved our understanding of IV iron administration safety in patients with CKD. Third generation IV iron compounds have minimized hypersensitivity reactions while allowing high doses to be administered safely and rapidly in non-dialysis-dependent CKD patients. However, differences in safety profiles such as hypophosphatemia require further study and therapy should be tailored to the individual. Clinicians should feel confident in using IV iron therapy.

Iron deficiency after kidney transplantation

Iron deficiency (ID) is highly prevalent in kidney transplant recipients (KTRs) and has been independently associated with an excess mortality risk in this population. Several causes lead to ID in KTRs, including inflammation, medication and an increased iron need after transplantation. Although many studies in other populations indicate a pivotal role for iron as a regulator of the immune system, little is known about the impact of ID on the immune system in KTRs. Moreover, clinical trials in patients with chronic kidney disease or heart failure have shown that correction of ID, with or without anaemia, improves exercise capacity and quality of life, and may improve survival. ID could therefore be a modifiable risk factor to improve graft and patient outcomes in KTRs; prospective studies are warranted to substantiate this hypothesis.

Usefulness of the StrongKids Screening Tool in Detecting Anemia and Inflammation in Hospitalized Pediatric Patients

Objective: To assess whether the nutritional risk classified by StrongKids is associated with anemia and inflammation (total leukocytes and C-reactive protein (CRP)), as well as to compare the ability of StrongKids with anthropometry in identifying these changes in hospitalized pediatric patients.Methods: Cross-sectional study with patients admitted to the pediatric ward of a public hospital in Brazil, from 2014 to 2018. The experimental protocol included: nutritional risk screening by StrongKids; weight and height measurements; and biochemical tests (complete blood count and C-reactive protein - CRP). Sensitivity, specificity, positive predictive value and negative predictive value were calculated to assess the ability of StrongKids and anthropometry to identify patients with the biochemical changes.Results: The study included 482 patients (54.2% male), with a median age of 2.7 years. The frequency of nutritional risk (medium or high) was 85.9% and the prevalence of malnutrition (acute and/or chronic) was 20.2%. Overall, of the patients evaluated, 40.2% had anemia, 28.2% leukocytosis, and 78.0% high CRP. Children and adolescents classified as at nutritional risk (moderate/high) had lower levels of hemoglobin and higher levels of CRP and total leukocytes, as well as a higher frequency of leukocytosis, high CRP and the three alterations combined when compared with individuals at low risk. No association was found between anthropometric variables and biochemical alterations. The sensitivity of nutritional screening was high to detect all biochemical alterations and was superior to the anthropometric assessment.Conclusion: StrongKids was associated with alterations in biochemical parameters with a better performance than anthropometry.

Iron Administration, Infection, and Anemia Management in CKD: Untangling the Effects of Intravenous Iron Therapy on Immunity and Infection Risk

Patients with chronic kidney disease (CKD) are at increased risk for infection, attributable to immune dysfunction, increased exposure to infectious agents, loss of cutaneous barriers, comorbid conditions, and treatment-related factors (eg, hemodialysis and immunosuppressant therapy). Because iron plays a vital role in pathogen reproduction and host immunity, it is biologically plausible that intravenous iron therapy and/or iron deficiency influence infection risk in CKD. Available data from preclinical experiments, observational studies, and randomized controlled trials are summarized to explore the interplay between intravenous iron and infection risk among patients with CKD, particularly those receiving maintenance hemodialysis. The current evidence base, including data from a recent randomized controlled trial, suggests that proactive judicious use of intravenous iron (in a manner that minimizes the accumulation of non-transferrin-bound iron) beneficially replaces iron stores while avoiding a clinically relevant effect on infection risk. In the absence of an urgent clinical need, intravenous iron therapy should be avoided in patients with active infection. Although serum ferritin concentration and transferrin saturation can help guide clinical decision making about intravenous iron therapy, definition of an optimal iron status and its precise determination in individual patients remain clinically challenging in CKD and warrant additional study.

Iron Metabolism and Brain Development in Premature Infants

Iron is important for a remarkable array of essential functions during brain development, and it needs to be provided in adequate amounts, especially to preterm infants. In this review article, we provide an overview of iron metabolism and homeostasis at the cellular level, as well as its regulation at the mRNA translation level, and we emphasize the importance of iron for brain development in fetal and early life in preterm infants. We also review the risk factors for disrupted iron metabolism that lead to high risk of developing iron deficiency and subsequent adverse effects on neurodevelopment in preterm infants. At the other extreme, iron overload, which is usually caused by excess iron supplementation in iron-replete preterm infants, might negatively impact brain development or even induce brain injury. Maintaining the balance of iron during the fetal and neonatal periods is important, and thus iron status should be monitored routinely and evaluated thoroughly during the neonatal period or before discharge of preterm infants so that iron supplementation can be individualized.

The Role of the Status of Selected Micronutrients in Shaping the Immune Function

OBJECTIVE

This narrative review gives an overview on the essential role of adequate nutrition to an optimally functioning immune defence. Micronutrients act as regulators of the immune response, with the focus of this review on the immunomodulatory effects of the trace elements iron, zinc and selenium, and the vitamins A, D, E, C, B6 and B12 and folic acid.

RESULTS

Iron deficiency especially impairs the Th1 cell-borne cellular immunity. T lymphocytes are also most affected by a deficiency of zinc, needed for their maturation and the balance between the different T cell subpopulations and acting as a redox signal in the regulation of many enzymes. Selenium is also involved in redox reactions as the glutathione peroxidases and other redox enzymes are selenoproteins. Selenium status has shown special effects on cellular immunity and resistance to viral infections. Vitamin A in the form of retinoic acid induces a humoral Th2 cell response via antigen-presenting cells and is involved in maintaining intestinal immune defence and tolerance through its nuclear receptor RAR and via kinase signalling cascades. Immune tolerance is particularly promoted by vitamin D acting through dendritic cells to stimulate the differentiation of regulatory T cells. Vitamin E has antiinflammatory effects and stimulates naïve T cells especially in the elderly. Besides its antioxidative properties, vitamin C has effects on cell signalling and epigenetic regulation. The B vitamins are required for cytotoxic cellular immunity and modulate T cell responses.

CONCLUSION

A diverse diet and regular exposure to sunlight are the best sources for a balanced nutrient supply to maintain an optimal immune defence.

Iron deficiency anemia-related gut microbiota dysbiosis in infants and young children: A pilot study

Nutritional iron deficiency (ID) causes not only anemia but also malfunction of the entire human organism. Recently, a role of the gut microbiota has been hypothesized, but limited data are available especially in infants. Here, we performed a pilot study to explore the gut microbiota in 10 patients with iron deficiency anemia (IDA) and 10 healthy controls aged 6-34 months. Fresh stool samples were collected from diapers, and the fecal microbiota was profiled by next-generation sequencing of the V3-V4 hypervariable region of the 16S rRNA gene. Except for diet diversity, the breastfeeding status at the enrollment, the exclusive breastfeeding duration, and the introduction of complementary foods did not differ between groups. Distinct microbial signatures were found in IDA patients, with increased relative abundance of Enterobacteriaceae (mean relative abundance, patients vs. controls, 4.4% vs. 3.0%) and Veillonellaceae (13.7% vs. 3.6%), and reduced abundance of Coriobacteriaceae (3.5% vs. 8.8%) compared to healthy controls. A decreased Bifidobacteriaceae/Enterobacteriaceae ratio was observed in IDA patients. Notwithstanding the low sample size, our data highlight microbiota dysbalance in IDA worth for further investigations, aimed at unraveling the ID impact on the microbiome trajectory in early life, and the possible long-term consequences.