Nanobodies (Nbs) serve as powerful tools in immunoassays. However, their small size and monovalent properties pose challenges for practical application. Multimerization emerges as a significant strategy to address these limitations, enhancing the utilization of nanobodies in immunoassays. Herein, we report the construction of a Salmonella-specific fenobody (Fb) through the fusion of a nanobody to ferritin, resulting in a self-assembled 24-valent nanocage-like structure. The fenobody exhibits a 35-fold increase in avidity compared to the conventional nanobody while retaining good thermostability and specificity. Leveraging this advancement, three ELISA modes were designed using Fb as the capture antibody, along with unmodified Nb422 (FbNb-ELISA), biotinylated Nb422 (FbBio-ELISA), and phage-displayed Nb422 (FbP-ELISA) as the detection antibody, respectively. Notably, the FbNb-ELISA demonstrates a detection limit (LOD) of 3.56 × 104 CFU/mL, which is 16-fold lower than that of FbBio-ELISA and similar to FbP-ELISA. Moreover, a fenobody and nanobody sandwich chemiluminescent enzyme immunoassay (FbNb-CLISA) was developed by replacing the TMB chromogenic substrate with luminal, resulting in a 12-fold reduction in the LOD. Overall, the ferritin-displayed technology represents a promising methodology for enhancing the detection performance of nanobody-based sandwich ELISAs, thereby expanding the applicability of Nbs in food detection and other fields requiring multivalent modification.

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired hematologic disorder characterized by a loss of glycosyl-phosphatidyl-inositol-linked (GPI) proteins on various hematopoietic cells. Some GPI proteins are involved in the regulation of the complement system, and their absence renders erythrocytes susceptible to complement-mediated lysis. Current standard of care in PNH is to block the complement system at the level of C5 using ravulizumab or eculizumab; however, some patients with PNH may develop extravascular hemolysis (EVH) during treatment with C5 inhibitors. The proximal complement inhibitor iptacopan has recently been shown to be efficacious in patients with PNH. This article reports on a 43-year-old female patient with PNH who was successfully treated with iptacopan. The patient had received ravulizumab for several years and developed a clinically relevant EVH. After obtaining informed consent, the patient received oral iptacopan 200 mg twice daily and ravulizumab was discontinued. Over the next few weeks hemoglobin levels and reticulocyte counts normalized. The patient reported mild flushes with erythema, chills, and mild muscle pain, all of which resolved during follow-up. No breakthrough hemolysis occurred, and no severe adverse events were recorded.

UNASSIGNED: Major Thalassemia patients suffer from iron overload and organ damage, especially heart and liver damage. Early diagnosis and treatment with a chelator can reduce the complications and mortality of iron overload. Therefore, we aimed to investigate the biochemical and hematological predictors as an alternative and indirect indicator of iron deposition in heart and liver cells in comparison with the MRI T2* method as the gold standard.
UNASSIGNED: MRI T2* was evaluated in the heart and liver tissues of 62 major beta-thalassemia patients undergoing regular transfusion and chelator therapy. Biochemical and hematological factors were also measured, including serum ferritin, serum electrolytes, liver enzymes, hemoglobin, blood glucose, and serum magnesium. The correlation between these factors was assessed using statistical evaluations.
UNASSIGNED: Serum ferritin had a positive and significant correlation with liver siderosis based on MRI T2* (p-value = .015), and no significant association was observed with cardiac siderosis (p-value = .79). However, there was a significant positive correlation between cardiac iron deposition and fasting blood sugar level (p-value = -.049), and plasma level of liver enzymes (alanine aminotransferase (ALT) (p-value = .001), aspartate aminotransferase (AST ((p-value = .01)). Moreover, there was a significant negative correlation between cardiac iron overload and plasma magnesium level (p-value = .014). According to MRI T2*, there was no significant correlation between cardiac and hepatic iron overload (p value = .36).
UNASSIGNED: An increase in blood sugar or liver enzymes and a decrease in serum magnesium was associated with an increase in cardiac iron overload based on MRI T2*. Liver iron overload based on MRI T2* had a significant correlation with serum ferritin.

Aurothiomalate (AuTM) is an FDA-approved antiarthritic gold drug with unique anticancer properties. To enhance its anticancer activity, we prepared a bioconjugate with human apoferritin (HuHf) by attaching some AuTM moieties to surface protein residues. The reaction of apoferritin with excess AuTM yielded a single adduct, that was characterized by ESI MS and ICP-OES analysis, using three mutant ferritins and trypsinization experiments. The adduct contains ~3 gold atoms per ferritin subunit, arranged in a small cluster bound to Cys90 and Cys102. MD simulations provide a plausible structural model for the cluster. The adduct was evaluated for its pharmacological properties and was found to be significantly more cytotoxic than free AuTM against A2780 cancer cells mainly due to higher gold uptake. NMR-metabolomics showed that AuTM bound to HuHf and free AuTM induced qualitatively similar changes in treated cancer cells, indicating that the effects on cell metabolism are approximately the same, in agreement with independent biochemical experiments. In conclusion, we have demonstrated here that a molecularly precise bioconjugate formed between AuTM and HuHf exhibits anticancer properties far superior to the free drug, while retaining its key mechanistic features. Evidence is provided that human ferritin can serve as an excellent carrier for this metallodrug.

UNASSIGNED: Numerous clinical trials affirm the efficacy and safety of IV iron to treat cancer-related anemia (CRA). Nonetheless, evaluation and treatment of CRA remains suboptimal.
UNASSIGNED: This review summarizes CRA therapy with a focus on iron deficiency and its treatment. The literature search was conducted using the National Library of Medicine (PubMed) database from 2004 to 2024. Topics reviewed include CRA pathophysiology, laboratory diagnosis of iron deficiency, a summary of clinical trial results using IV iron to treat CRA, and safety aspects.
UNASSIGNED: Despite overwhelming positive efficacy and safety data, IV iron remains underutilized to treat CRA. This is likely due to persistent (unfounded) concerns about IV iron safety and lack of physician awareness of newer clinical trial data. This leads to poor patient quality of life and patient exposure to anemia treatments that have greater safety risks than IV iron. Solutions to this problem include increased educational efforts and considering alternative treatment models in which other providers separately manage CRA. The recent availability of new oral iron therapy products that are effective in treating anemia of inflammation has the potential to dramatically simplify the treatment of CRA.

UNASSIGNED: Iron deficiency is known to impair muscle function and reduce athletic performance, while vitamin D has been reported to induce iron deficiency. However, the mechanism underlying exercise-induced changes in iron metabolism and the involvement of vitamins in this mechanism are unclear. The present study examined changes in biological iron metabolism induced by continuous training and the effects of vitamin D on these changes.
UNASSIGNED: Diet, physical characteristics, and blood test data were collected from 23 female high school students in a dance club on the last day of each of a 2-month continuous training period and a 2-week complete rest periods.
UNASSIGNED: Serum hepcidin-25 levels were significantly lower during the training period than the rest period (p = 0.013), as were the red blood cell count, hemoglobin, and hematocrit (all p < 0.001). Serum erythropoietin was significantly higher (p = 0.001) during the training period. Significant positive correlations were observed between 25(OH)D levels and serum iron, serum ferritin, and transferrin saturation during the training period. Multiple regression analysis with serum 25(OH)D level as the dependent variable and serum ferritin and iron levels as independent variables during the training period revealed a significant association with serum ferritin.
UNASSIGNED: Continuous training may promote hemolysis and erythropoiesis, contributing to the suppression of hepcidin expression. The relationship between serum 25(OH)D and iron in vivo may be closely related to metabolic changes induced by the exercise load.

This editorial discusses a case-control study by Ibrahim et al, published in the recent issue of the World Journal of Clinical Pediatrics. Childhood bronchial asthma is a chronic inflammatory respiratory disease. It was found that an increase in oxidative stress leads to a decrease in antioxidants causing oxidative damage to mitochondrial respiratory chain complexes resulting in the inflammation of the airway, hypersecretion of mucus causing a cascade of clinical manifestations ranging from recurrent episodes of coughing, wheezing, and breathlessness to shortness of breath. Since oxidative stress mediates the inflammatory response in asthma, the supplementation of anti-oxidants can be one strategy to manage this disease. Zinc is one such antioxidant that has attracted much attention about asthma and airway inflammation. Zinc is a crucial trace element for human metabolism that helps to regulate gene expression, enzyme activity, and protein structure. Apart from zinc, free serum ferritin levels are also elevated in case of inflammation. Several previous studies found that ferritin levels may also help determine the pathology of disease and predict prognosis in addition to tracking disease activity. However, this study\'s results were different from the findings of the previous studies and the zinc levels did not show a significant difference between asthmatic children and non-asthmatic children but ferritin levels were significantly high in asthmatic children as compared to the controls. Hence, the possible role of the biochemical nutritional assessment including zinc and ferritin as biomarkers for asthma severity should be assessed in the future.

The microbiota significantly impacts digestive epithelium functionality, especially in nutrient processing. Given the importance of iron for both the host and the microbiota, we hypothesized that host-microbiota interactions fluctuate with dietary iron levels. We compared germ-free (GF) and conventional mice (SPF) fed iron-containing (65 mg/Kg) or iron-depleted (<6 mg/Kg) diets. The efficacy of iron privation was validated by iron blood parameters. Ferritin and Dmt1, which represent cellular iron storage and transport respectively, were studied in tissues where they are abundant: the duodenum, liver and lung. When the mice were fed an iron-rich diet, the microbiota increased blood hemoglobin and hepcidin and the intestinal ferritin levels, suggesting that the microbiota helps iron storage. When iron was limiting, the microbiota inhibited the expression of the intestinal Dmt1 transporter, likely via the pathway triggered by Hif-2α. The microbiota assists the host in storing intestinal iron when it is abundant and competes with the host by inhibiting Dmt1 in conditions of iron scarcity. Comparison between duodenum, liver and lung indicates organ-specific responses to microbiota and iron availability. Iron depletion induced temporal changes in microbiota composition and activity, reduced α-diversity of microbiota, and led to Lactobacillaceae becoming particularly more abundant after 60 days of privation. By inoculating GF mice with a simplified bacterial mixture, we show that the iron-depleted host favors the gut fitness of Bifidobacterium longum.

Since the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) outbreak, several solutions have been proposed to manage the disease. The most viable option for controlling this virus is to produce effective vaccines. Most of the current SARS-CoV-2 vaccines have focused on the infusion spike protein. Spike exists as a trimer and plays a vital role in infecting host cells by binding to the Angiotensin-Converting Enzyme 2 (ACE2) receptor through its Receptor Binding Domain (RBD). Ferritin protein, a naturally occurring iron-storage protein, has gained attention for vaccine production due to its self-assembling property, non-toxic nature, and biocompatibility. Ferritin nanocages have recently been employed in the development of a SARS-CoV-2 vaccination eliciting not only long-term protective memory cells but also a sustained antibody response. In this study, a combination of in silico investigations including molecular docking, molecular dynamics simulations, and immune simulations were carried out to computationally model the monomeric spike protein on the ferritin nanocage as well as to evaluate its stability and interactions for the first time. The structural dynamics of the modeled complex demonstrated noticeable stability. In particular, the Receptor Binding Domain (RBD) and ferritin within the monomeric spike-ferritin complex illustrated significant stability. The lack of alterations in the secondary structure further supported the overall steadiness of the complex. The decline in the distance between ferritin and spike suggests a strong interaction over time. The cross-correlation matrices revealed that the monomeric spike and ferritin move towards each other supporting the stable interaction between spike and ferritin. Further, the orientation of monomeric spike protein within the ferritin unit facilitated the exposure of critical epitopes, specifically upward active Receptor Binding Domain (RBD), enabling effective interactions with the ACE2 receptor. The immune simulations of the model indicated high-level stimulations of both cellular and humoral immunity in the human body. It was also found that the employed model is effective regardless of the mutated spikes in different variants. These findings shed light on the current status of the SARS-CoV-2-ferritin nanoparticle vaccines and could be used as a framework for other similar vaccine designs.

Classical swine fever (CSF), caused by the classical swine fever virus (CSFV), results in significant economic losses to the swine industry in many countries. Vaccination represents the primary strategy to control CSF and the CSFV E2 protein is known as the major protective antigen. However, the E2 protein expressed or presented by different systems elicits distinct immune responses. In this study, we established a stable CHO cell line to express the E2 protein and delivered it using self-assembled ferritin nanoparticles (NPs). Subsequently, we compared the adaptive immune responses induced by the E2-ferritin NPs and the monomeric E2 protein produced by the CHO cells or a baculovirus expression system. The results revealed that the NP-delivered E2 protein elicited higher titers of neutralizing antibodies than did the monomeric E2 protein in pigs. Importantly, only the NP-delivered E2 protein significantly induced CSFV-specific IFN-γ-secreting cells. Furthermore, all the pigs inoculated with the E2-ferritin NPs were completely protected from a lethal CSFV challenge infection. These findings demonstrate the ability of the E2-ferritin NPs to protect pigs against the lethal CSFV challenge by eliciting robust humoral and cellular immune responses.