Transferrin Binding Research Articles

Diabesity negatively affects transferrin saturation and iron status. The DICARIVA study

The relationship between iron status, obesity and type 2 diabetes mellitus (T2DM) has scarcely been tested. This study hypothesizes that patients with obesity and T2DM have altered iron metabolism. 537 T2DM patients were selected from the cross-sectional DICARIVA study excluding patients with high-sensitivity-C-reactive-protein (hs-CRP)≥ 10mg/L. Three groups according to body mass index (BMI) and waist perimeter (WP) were analysed: a) BMI<30kg/m2, non-high WP (n=105); b) BMI<30kg/m2, high WP (n=202); and c) diabesity, BMI≥ 30kg/m2, high WP (n=230). Group differences on cardiometabolic and iron status markers were tested. Women had significantly lower iron, ferritin, and transferrin saturation (TSAT) but higher transferrin and total iron binding capacity than men. Triglycerides/HDL-c ratio, as insulin-resistance (IR) marker, was higher in men while hs-CRP in women. TSAT was inversely related to BMI and hs-CRP. The diabesity group showed the highest hs-CRP (p<0.001) and IR (p<0.001) with the lowest TSAT (p=0.003). Low TSAT was highly prevalent in diabesity, mainly in women, suggesting that IR, inflammation, and abdominal adiposity alter iron transport and accumulation. The convenience of iron supplementation in diabesity patients with low TSAT should be urgently assessed, due the pro-oxidant effects of excess iron.

Luminescent naphthalimide-tagged ruthenium(ii)-arene complexes: cellular imaging, photocytotoxicity and transferrin binding.

Two water-soluble piano-stool shaped ruthenium(ii)-arene complexes, [RuII(η6-p-cymene)(L)Cl2] [RuLCl] and [RuII(η6-p-cymene)(L)(PTA)Cl] [RuLPTA], were designed as emissive photocytotoxic agents tagged with morpholine as the lysosome targeting moiety. Here, L = N-(2-morpholinoethyl)-4-(2-aminoethyl)amino-naphthalimide, and PTA = 1,3,5-triaza-7-phosphatricyclo-[3.3.1.1]decane. The crystal structure of [RuLCl] exhibits the pseudooctahedral 'three-legged piano-stool' geometry, wherein Ru(ii) is bound to the η6-p-cymene moiety as a base and two chlorides and the amine-N of the ligand L occupies the three legs of the stool. The complexes exhibited both the possibility of covalent adduct formation via the hydrolyzed Ru-Cl bond and non-covalent intercalation binding through planar naphthalimide moieties. The complexes showed enhanced photo-cytotoxicity under low-power blue LED light irradiation (λmax = 448 nm) mediated by 1O2, thereby acting as potential PDT agents. Fluorescence microscopy studies revealed that luminescent complexes preferentially localized in both the lysosomes and nucleus for effectively targeting and damaging the nuclear DNA for PDT effects. Due to enhanced lipophilicity of [RuLCl], it showed higher internalization into MCF-7 cell, measured in terms of the ruthenium content using ICP-MS. The interaction of the complexes with human transferrin (hTf) proteins was studied through molecular docking calculations, suggesting favorable binding through histidine residues and possible internalization into cancer cells via TfR-mediated endocytosis. The luminescence properties of the complexes were well-utilized to study their cellular uptake mechanism via endocytosis using fluorescence microscopy.

Ağır Demir Eksikliği olan Çocuk Hastalarda Vitamin D Düzeyi

Bu çalışmada ağır demir eksikliği anemisi olan çocuklarda Vitamin D eksikliği sıklığının belirlenmesi amaçlanmıştır. Bu çalışmaya 6-72 ay arasında ağır demir eksikliği anemisi olan 60 hasta ile benzer yaş ve cinsiyette 60 sağlıklı çocuk dahil edildi. Hasta grubuna kan hemoglobin düzeyi 7 g/dl'nin altında ağır demir eksikliği anemisi tanısı alan hastalar dahil edildi. Aneminin etiyolojisi ile ilgili olarak hasta grubundan hemogram, retikülosit sayımı, biyokimyasal analizler, serum demir ve demir bağlama kapasitesi, transferrin satürasyonu, ferritin, vitamin B12, folik asit ve serum Vitamin D düzeyleri için kan örneği alındı. Vitamin D eksikliği (<20 ng/mL) hasta grubunun %75'inde (n=45), kontrol grubunun %1.7'sinde (n=1) mevcuttu (p<0.001). Hasta grubunun Vitamin D düzeyi (16.2±13.3 ng/ml), kontrol grubuna (36.3±15.1 ng/ml) göre anlamlı olarak düşüktü (p<0.05). Kontrol grubunda gelişme geriliği olan çocuk bulunmazken, hasta grubunun %16.7'sinde gelişme geriliği vardı (p<0.001). Vitamin D eksikliği çok yüksek prevalansa sahiptir ve ağır demir eksikliği anemisi olan hastalarda Vitamin D düzeyi anlamlı olarak düşük bulunmuştur. Sonuç olarak, ciddi demir eksikliği anemisi olan hastalar Vitamin D eksikliği açısından değerlendirilmeli ve tedavi edilmelidir.

Blood-brain barrier transport using a high affinity, brain-selective VNAR antibody targeting transferrin receptor 1.

Transfer across the blood-brain barrier (BBB) remains a significant hurdle for the development of biopharmaceuticals with therapeutic effects within the central nervous system. We established a functional selection method to identify high affinity single domain antibodies to the transferrin receptor 1 (TfR1) with efficient biotherapeutic delivery across the BBB. A synthetic phage display library based on the variable domain of new antigen receptor (VNAR) was used for in vitro selection against recombinant human TfR1 ectodomain (rh-TfR1-ECD) followed by in vivo selection in mouse for brain parenchyma penetrating antibodies. TXB2 VNAR was identified as a high affinity, species cross-reactive VNAR antibody against TfR1-ECD that does not compete with transferrin or ferritin for receptor binding. IV dosing of TXB2 when fused to human Fc domain (TXB2-hFc) at 25nmol/kg (1.875mg/kg) in mice resulted in rapid binding to brain capillaries with subsequent transport into the brain parenchyma and specific uptake into TfR1-positive neurons. Likewise, IV dosing of TXB2-hFc fused with neurotensin (TXB2-hFc-NT) at 25nmol/kg resulted in a rapid and reversible pharmacological response as measured by body temperature reduction. TXB2-hFc did not elicit any acute adverse reactions, bind, or deplete circulating reticulocytes or reduce BBB-expressed endogenous TfR1 in mice. There was no evidence of target-mediated clearance or accumulation in peripheral organs except lung. In conclusion, TXB2 is a high affinity, species cross-reactive, and brain-selective VNAR antibody to TfR1 that rapidly crosses the BBB and exhibits a favorable pharmacokinetic and safety profile and can be readily adapted to carry a wide variety of biotherapeutics from blood to brain.

Bioelectrochemistry of Neuronal Protein Tauoral

Tau is a neuronal protein and one of the biomarkers of neurodegenerative diseases, such as Alzheimer’s disease. Tau protein undergoes post-translational modifications, aggregation, and is a viable drug target. In addition, this protein is a vital biomarker in biological fluids towards early detection of neurodegenerative diseases. We reported on using electrochemical impedance spectroscopy and cyclic voltammetry for detection of protein-protein interactions (1), protein-ligand interactions (2), enzymatic catalysis and enzyme inhibition (3) while focusing on tau protein and its biochemistry. For example, tau-tau, tau-ferritin, tau-transferring protein interactions were monitored, and protein kinase-catalyzed phosphorylation of tau protein was detected. The phosphorylation inhibitors, such as antibodies, were screened for their efficacies. New research directions in neuroelectrochemistry of tau protein alongside other neuronal biomarkers, such as Amyloid beta and alpha synuclein, will also be described. References A) Carlin, N., Martic-Milne, S. (2018). Anti-tau antibodies based electrochemical sensor for detection of tau protein. J. Electrochem. Soc.165: G3018-G3025. B) Jahshan, A., Esteves, J.O.V., Martic-Milne, S. (2016). Evaluation of ferritin and transferrin binding to tau protein. J. Inorg. Biochem. 162: 127-134. C) Esteves, J.O.V., Trzeciakiewicz, H., Loeffler, D.A., Martic, S. (2015). Effects of tau domain-specific antibodies and intravenous immunoglobulin on tau aggregation and aggregate degradation. Biochemistry. 54: 15-18.Trzeciakiewicz, H., Esteves, J.O.V., Carlin, N., Martic, S. (2015). Electrochemistry of heparin binding to tau protein on Au surfaces. Electrochim. Acta. 162: 24-30,Esteves, J.O.V., Martic-Milne, S. (2016). Electrochemical detection of anti-tau antibodies binding to tau protein and inhibition of GSK-3-β-catalyzed phosphorylation. Anal. Biochem. 496: 55-62

Proof of Concept for Prevention of Natural Colonization by Oral Needle-Free Administration of a Microparticle Vaccine.

There has been substantial interest in the development of needle-free vaccine administration that has led to a variety of approaches for delivery through the skin for induction of a systemic immune response. The mucosal administration of vaccines has inherently been needle-free, but the simple application of vaccines on the mucosal surface by itself does not lead to mucosal immunity. Since many important bacterial infections develop after initial colonization of the upper respiratory tract of the host, prevention of colonization could not only prevent infection but also eliminate the reservoir of pathogens that reside exclusively in that ecologic niche. This study was designed to provide proof of concept for a needle-free immunization approach that would reduce or eliminate colonization and prevent infection. In order to accomplish this a microparticle vaccine preparation was delivered just below the oral mucosal epithelial cell layer where it would lead to a robust immune response. A vaccine antigen (mutant transferrin binding protein B) shown to be capable of preventing infection in pigs was incorporated into a polyphosphazene microparticle preparation and delivered by a needle-free device to the oral sub-epithelial space of pigs. This vaccination regimen not only provided complete protection from infection after intranasal challenge by Glaesserella parasuis but also eliminated natural colonization by this bacterium. Notably, the complete prevention of natural colonization was dependent upon delivery of the microparticle preparation below the epithelial layer in the oral mucosa as intradermal or intramuscular delivery was not as effective at preventing natural colonization. This study also demonstrated that a primary immunization in the presence of maternal antibody limited the resulting antibody response but a robust antibody response after the second immunization indicated that maternal antibody did not prevent induction of B-cell memory.

Virulence Gene Pattern of Pasteurella multocida Isolates of Buffalo in Association to Capsule Biosynthesis Genes

Background: Pasteurella multocida is the causative agent of many economically important diseases in a wide range of hosts. The mechanisms by which these bacteria can invade the mucosa, evade innate immunity and cause systemic disease are slowly being elucidated. Many key virulence factors are yet to be identified, including those required for initial attachment and invasion of host cells and for persistence in a relatively nutrient poor and hostile environment. This has led to intensive research to understand host adaptation mechanisms and virulence factors in order to develop effective vaccines. Methods: The present study was carried out to know the distribution of virulence genes viz., haemoglobin binding proteins (hgbA and hgbB), outer membrane protein (ompH), fimbrial antigen (ptfA), filamentous haemagglutinin (pfhA) and transferrin binding protein (tbpA) by PCR in P. multocida CapA isolates from apparently healthy or carrier animals and CapB isolates from field Haemorrhagic septicemia (HS) cases to monitor the epidemiological associations of virulence genes in Cap A and Cap B isolates.Result: The study revealed that all the six virulence associated genes were present in Cap B isolates. None of the Cap A isolates harboured tbpA and pfhA genes. These two genes were closely related to serotype B causing Haemorrhagic septicemia and were epidemiologically associated with disease status.

Cancer immunosensor based on apo and holo transferrin binding

Anelectrochemical immunosensor was developed for the determination of apo-Tf (non-iron-bound) and holo-Tf (iron-bound) using polyclonal antibody transferrin (anti-Tf) immobilized at an electrode surface as a biorecognition platform. The monitoring was based on the anti-Tf binding with both Tf forms which allows the detection of cancer cells due to the constant iron cycle and the overexpression of anti-Tf on the cancer cell surface. The immunosensor characterization was performed using electrochemical impedance spectroscopy (EIS), which evaluated the impedimetric biorecognition of the antigens-antibody by the use of K4Fe(CN)6 redox group. The immunosensor was able to detect both forms of Tf in terms of charge transfer resistance (Rct). Analytical curves showed a limit of detection of 0.049 and 0.053ngmL-1 for apo-Tf and holo-Tf, respectively. The immunosensor was applied tothe detection of the two cancer cells A549 (lung carcinoma) and MCF-7 (breast carcinoma) and compared with BHK570, a healthy cell line. The impedimetric response of healthy cells differs significantly from that of the cancerous cells, as revealed by a Dunnett's test in 95% confidence level-ca. 102 cells mL-1-indicating the feasibility of the immunosensor to discriminate both types of cells. The indirect detection of anti-Tf based on apo-Tf and holo-Tf binding can be considered an advanced approach for cancer recognition. Graphical abstract.

Transferrin Binding Protein B and Transferrin Binding Protein A2 Expand the Transferrin Recognition Range of Histophilus somni.

The bacterial bipartite transferrin receptor is an iron acquisition system that several important human and animal pathogens require for survival. It consists of the TonB-dependent transporter transferrin binding protein A (TbpA) and the surface lipoprotein transferrin binding protein B (TbpB). Curiously, the Tbps are only found in host-specific pathogens and are themselves host specific, meaning that they will bind to the transferrin of their host species but not to the transferrins of other animal species. While this phenomenon has long been established, neither the steps in the evolutionary process that led to this exquisite adaptation for the host nor the steps that could alter it are known. We sought to gain insight into these processes by studying Tbp specificity in Histophilus somni, an economically important pathogen of cattle. A past study showed that whole cells of H. somni specifically bind bovine transferrin but not transferrin from sheep and goats, two bovids whose transferrins share 93% amino acid sequence identity with bovine transferrin. To our surprise, we found that H. somni can use sheep and goat transferrins as iron sources for growth and that HsTbpB, but not HsTbpA, has detectable affinity for sheep and goat transferrins. Furthermore, a third transferrin binding protein found in H. somni, HsTbpA2, also showed affinity for sheep and goat transferrins. Our results suggest that H. somni TbpB and TbpA2 may contribute to broadening the host transferrin recognition range of H. somniIMPORTANCE Host-restricted pathogens infect a single host species or a narrow range of host species. Histophilus somni, a pathogen that incurs severe economic losses for the cattle industry, infects cattle, sheep, and goats but not other mammals. The transferrin binding proteins, TbpA and TbpB, are thought to be a key iron acquisition system in H. somni; however, despite their importance, H. somni TbpA and TbpB were previously shown to be cattle transferrin specific. In our study, we find that H. somni TbpB and another little-studied Tbp, TbpA2, bind sheep and goat transferrins, as well as bovine transferrin. Our results suggest that TbpB and TbpA2 may allow for host range expansion and provide a mechanism for how host specificity in Tbp-encoding pathogens can be altered.

Vanadium(V/IV)-Transferrin Binding Disrupts the Transferrin Cycle and Reduces Vanadium Uptake and Antiproliferative Activity in Human Lung Cancer Cells.

The role of vanadium binding to transferrin (Tf) in the biological activities of vanadium-based drugs is a matter of considerable debate. In order to determine whether V(V) and/or V(IV) binding to Tf (in apo, monoferric(III), and diferric(III) forms) enhances or inhibits biological activities, cellular V uptake and in vitro antiproliferative activity were examined in the presence and absence of different forms of Tf and other biomolecules under normoxic conditions. These data were combined with studies on V-Tf binding in cell culture medium and its role in Tf interactions with transferrin receptor 1 (TfR1), using the biolayer interferometry (BLI) model of the Tf cycle that was developed in our group. The results showed that both V(V) and V(IV) oxidation states efficiently bind to vacant Fe(III) binding sites of Tf even in the presence of a 20-fold molar excess of albumin, although V does not displace Tf-bound Fe(III) under these conditions. Binding of V(V) or V(IV) to Tf in cell culture medium drastically reduced its cellular uptake and antiproliferative activity in the A549 (human lung cancer) cell line that expresses TfR1. BLI and gel electrophoresis studies showed that V(V/IV) binding to partially Fe(III) saturated Tf did not enhance the affinity of Tf binding to TfR1 at pH 7.4 but did disrupt Tf conformational changes under endosome-mimicking conditions (pH 5.6, 0.10 mM citrate). Hence, it is postulated that the absence of a significant cellular uptake of Tf-bound V(V/IV) is likely to be due to the return of undissociated V(V/IV)-Tf adducts to the cell surface after the endosomal step. Collectively, these data show that the biotransformation of V-based drugs leads to V(V/IV)-Tf binding in the blood serum and inhibits, rather than enhances, the biological activity of such drugs under aerobic conditions. These results indicate that the design of V-based drugs that are stable enough to survive in the blood, enter cells intact, and release the active components intracellularly is likely to be required for their clinical success.

P0847HEPATIC ERYTHROPOIETIN SYNTHESIS IS ENHANCED IN HEMODIALYSIS PATIENTS WHO DO NOT REQUIRE ERYTHROPOIESIS-STIMULATING AGENTS

Abstract Background and Aims Erythropoietin is synthesized in the liver during the fetal period and mainly in the kidney after birth. However, some patients with end-stage chronic kidney disease do not require the administration of erythropoiesis-stimulating agents (ESA) despite their damaged renal function. This study aimed to clarify the origin of extrarenal erythropoietin generation in these patients. Method The origin of erythropoietin was investigated by analyzing the erythropoietin glycation patterns based on the percentages of migrated isoforms (PMI). Sera of stable hemodialysis (HD) patients with (ESA group) or without (non-ESA group) ESA treatment and umbilical cord blood of newborns (UCB group), which contained erythropoietin of liver origin, were analyzed. The non-ESA group was determined as HD patients without ESA treatment for &amp;gt; 6 months. Informed consent was obtained from all included HD patients and from the parents or guardians of the newborns. This study was performed with permission from the institutional ethical committee and was registered as a clinical trial (no. R000033462 UMIN000029335). Results The mean duration of no ESA treatment in the non-ESA group was 29.2 months. There were no differences in major clinical parameters, including age and HD duration. The hemoglobin concentration in the ESA group was 107 ± 5 g/L (mean ± standard error), which was significantly lower than that in the non-ESA group (123 ± 4 g/L) (P = 0.025, unpaired Student’s t-test). The PMI values of the ESA, non-ESA, and UCB groups were 12.6 ± 11.4％, 61.2 ± 13.1%, and 65.0 ± 13.5％, respectively, and the PMI value of the ESA group was significantly lower than that of non-ESA or UCB group (one-way analysis of variance with Tukey-Kramer test), suggesting that the glycation pattern of erythropoietin in the non-ESA group was similar to that in the UCB group but different from that in the ESA group. No significant differences were found in the reticulocyte ratio, serum iron concentration, total iron binding capacity, and ferritin and transferrin saturation between the ESA and non-ESA groups. Conclusion These results suggest that patients in the non-ESA group had enhanced extrarenal erythropoietin synthesis and that their erythropoietin originated from the liver. Further analysis of the underlying mechanism may contribute to the development of internal extrarenal erythropoietin-stimulating therapy.

Physiological Animal Imaging with 68Ga-Citrate.

Gallium-68 is an ideal research and hospital-based PET radioisotope. The uptake mechanism of Gallium citrate is a combination of specific and non-specific processes, for example, vasodilatation, increased vascular permeability, plasma transferrin binding and lactoferrin and siderophores. In this study, by applying the 68Ge/68Ga generator product, a simple technique for the synthesis and quality control of 68Ga-citrate was introduced and was followed by preliminary animal studies. The synthesis of 68Ga-citrate was performed with a cationic method using the Scintomics automated synthesis system (Scintomics GmbH GRP module 4V). Since the standard procedure for quality control (QC) was not available, the definition of chemical and radiochemical purity of 68Ga-citrate was carried out according to the ICH Q2(R1) guideline. The standard QC tests were analysed with Scintomics 8100 radio-HPLC system equipped with a radioactivity detector. In this study, a New Zealand rabbit weighing 2520 g was used for PET/CT images. 68Ga-citrate synthesis was performed by a cationic method without using organic solvents. The labelling efficiency was found to be >98%. The HPLC method used to assess the radiochemical purity of 68Ga -citrate was validated as rapid, accurate and reproducible enough to apply it to patients safely. The physiological distribution of 68Ga-citrate was investigated in a healthy rabbit. The blood pool, liver, spleen, kidneys and growth plates were the most common sites of 68Ga-citrate involvement.

IRON DEFICIENCY IN HEART FAILURE

Background: Data on the burden of Iron deficiency (ID) in Heart failure (HF) patients in India are sparse and there is very little information available about the prevalence of iron deficiency in heart failure with mid-range (HFmrEF) and preserved ejection fraction (HFpEF) in comparison to heart failure with reduced ejection-fraction (HFrEF).&#x0D; Aims and Objective: This study was carried out with aim to evaluate iron profile in HF patients and to know the prevalence of ID in HFpEF, HFmrEF and HFrEF in our region.&#x0D; Materials and Methods: Patients with clinically diagnosed HF were enrolled in the study. This was a single tertiary care centre, prospective, observational study carried out from December 2017 to November 2018. Patients were classified into HFrEF, HFmrEF and HFpEF on echocardiography. Serum ferritin (micrograms per liter), serum iron (micrograms per liter), total iron binding capacity (micrograms per liter), transferrin (milligrams per deciliter), and transferrin saturation were measured to assess iron status. Absolute ID was defined as serum ferritin &lt; 100 mg/L and functional ID was defined as normal serum ferritin (100–300 mg/L) with low TSAT (&lt;20%).&#x0D; Results: A total of 120 patients of HF (66.7% males and 33.3% females) were studied. Out of 120 patients, 78 (65%) patients of HF had ID. Absolute ID was in 38.3% and functional ID was seen in 26.7% patients. 62.5% of males had ID, whereas, 70% of females had ID in HF. Patients with ID had higher NYHA Class, 35.9% compared to 23.8% patients without ID. ID was high in all subsets of HF. ID was found in 61.11% in HFrEF, 67.44% in HFmrEF and 69.57% in HFpEF. P-0.71. 14.1% patients had ID, but no anemia (p- 0.02). In anemic patients, ID was more (85.2%) than non anemic patients (69%).&#x0D; Conclusion: In our study, prevalence of ID was higher in patients of HF than that reported from western literature. HFpEF had higher prevalence of ID followed by HFmrEF and HFrEF, respectively. Literature is scanty about HFmrEF, our study has given an insight of ID in this subset of HF. ID can occur even without anemia and females are more prone to have ID in HF. Our study highlights the importance of diagnosis and treatment of ID in all subsets of HF, in order to improve quality of life, morbidity and mortality in patients of HF.&#x0D; Keywords: Iron deficiency, Heart Failure, Anemia, HFrEF, HFmrEF, HFpEF

Nanocrystal facet modulation to enhance transferrin binding and cellular delivery

Binding of biomolecules to crystal surfaces is critical for effective biological applications of crystalline nanomaterials. Here, we present the modulation of exposed crystal facets as a feasible approach to enhance specific nanocrystal–biomolecule associations for improving cellular targeting and nanomaterial uptake. We demonstrate that facet-engineering significantly enhances transferrin binding to cadmium chalcogenide nanocrystals and their subsequent delivery into cancer cells, mediated by transferrin receptors, in a complex biological matrix. Competitive adsorption experiments coupled with theoretical calculations reveal that the (100) facet of cadmoselite and (002) facet of greenockite preferentially bind with transferrin via inner-sphere thiol complexation. Molecular dynamics simulation infers that facet-dependent transferrin binding is also induced by the differential affinity of crystal facets to water molecules in the first solvation shell, which affects access to exposed facets. Overall, this research underlines the promise of facet engineering to improve the efficacy of crystalline nanomaterials in biological applications.

Regulation of the Transferrin Receptor Recycling in Hepatitis C Virus-Replicating Cells.

After binding of its ligand transferrin, the transferrin receptor (TfR) is internalized via early endosomes. Ligand and receptor can be recycled. α-Taxilin was identified as an essential factor for TfR recycling. Apart from its role for iron uptake, TfR is a coreceptor for hepatitis C virus (HCV) infection. In HCV-replicating cells, the amount of a-taxilin is decreased. This study aims to investigate the effect of decreased α-taxilin levels in HCV-replicating cells on recycling of TfR, its amount on the cell surface, on iron uptake, and the impact of a disturbed TfR recycling on HCV superinfection exclusion. TfR amount and localization were determined by CLSM and surface biotinylation. α-taxilin expression was modulated by CRISPR-Cas9 knockout, siRNA, and stable or transient overexpression. For analysis of HCV superinfection fluorophor-tagged reporter viruses were used. The amount of α-taxilin is decreased in HCV-infected cells. In accordance to this, the protein amount of TfR is significant lower in HCV-positve cells as compared to the control, while TfR expression is not affected. Due to the impaired recycling, internalized TfR is degraded by the endosomal/lysosomal system. The significant lower number of TfR molecules on the cell surface is reflected by reduced transferrin binding/internalization and strong reduction of intracellular iron level. Overexpression of α-taxilin in HCV-replicating cells rescues TfR recycling, augments TfR on the cell surface, and restores transferrin binding. The block of superinfection in HCV-replicating cells could be overcome by overexpression of α-taxilin. Taken together, the diminished level of α-taxilin in HCV-replicating cells prevents recycling of TfR leading to decreased transferrin binding and iron uptake. Disappearance of TfR from the cell surface could be a factor contributing to the exclusion of superinfection by HCV.

TfR1 binding with H-ferritin nanocarrier achieves prognostic diagnosis and enhances the therapeutic efficacy in clinical gastric cancer

H-ferritin (HFn) nanocarrier is emerging as a promising theranostic platform for tumor diagnosis and therapy, which can specifically target tumor cells via binding transferrin receptor 1 (TfR1). This led us to investigate the therapeutic function of TfR1 in GC. The clinical significance of TfR1 was assessed in 178 GC tissues by using a magneto-HFn nanoparticle-based immunohistochemistry method. The therapeutic effects of doxorubicin-loaded HFn nanocarriers (HFn-Dox) were evaluated on TfR1-positive GC patient-derived xenograft (GC-PDX) models. The biological function of TfR1 was investigated through in vitro and in vivo assays. TfR1 was upregulated (73.03%) in GC tissues, and reversely correlated with patient outcome. TfR1-negative sorted cells exhibited tumor-initiating features, which enhanced tumor formation and migration/invasion, whereas TfR1-positive sorted cells showed significant proliferation ability. Knockout of TfR1 in GC cells also enhanced cell invasion. TfR1-deficient cells displayed immune escape by upregulating PD-L1, CXCL9, and CXCL10, when disposed with IFN-γ. Western blot results demonstrated that TfR1-knockout GC cells upregulated Akt and STAT3 signaling. Moreover, in TfR1-positive GC-PDX models, the HFn-Dox group significantly inhibited tumor growth, and increased mouse survival, compared with that of free-Dox group. TfR1 could be a potential prognostic and therapeutic biomarker for GC: (i) TfR1 reversely correlated with patient outcome, and its negative cells possessed tumor-aggressive features; (ii) TfR1-positive cells can be killed by HFn drug nanocarrier. Given the heterogeneity of GC, HFn drug nanocarrier combined with other therapies toward TfR1-negative cells (such as small molecules or immunotherapy) will be a new option for GC treatment.

Compare Transferrin Binding Protein (Tbp A) Gene Virulence of Pasteurella Multocida Type B of Buffalo and Vaccine Septicemiaepizootica

Septicemia Epizootica (SE), is a fatal acute septicemia disease by Pasteurella multocida. B: 2, 5 and E: 2, 5 in cattle and buffalo. TbpA has a number of important role for bacterial cells, such as nutrient uptake, transport of molecules in and out of cells and interactions with the environment and host. P. multocida iron acquisition related gene, tbpA, has been considered as an important epidemiological marker. The purpose of this study was to compare the Transferrin Binding Protein A (TbpA) gene from P. multocidatype B of buffalo and it with vaccine strain. Characterization of TbpA of P. multocida and vaccine strain was done using PCR then sequencing. Sample used in this study were P. multocida local isolate from NTT and vaccine strain (Katha). Isolation and identification were performed using bacteriological culture and biochemically characterization. Results from PCR showed positive a tbpA gene on P. multocida local isolate and vaccine strainis. The comparison of the results of sequencing between the tbpa gene isolates P.multocida and vaccines showed deletion.

Iron Homstatin as a Marker on the Oxidative Stress in Patients for Diabetes Mellitus Type 2

The study included measurement of the level of glucose, iron, ferritin, transferrin‚ Total iron binding capacity, Ceruloplasmin Ferroxidase activity, peroxidase activity and lipid peroxidation in the serum of people with type 2 diabetes mellitus (T2DM). The study included (90) blood samples and divided into three groups (I‚ II‚ III) each of them (30) samples‚ (I) control group, (II, III) Type 2 diabetes patients with complications and without of complications, respectively. The results showed a significant increase in the level of glucose, iron, ferritin and lipid peroxidation in patients with type 2 diabetes with and without complications respectively compare with control group. While a decrease was observed efficacy of peroxidase and ferroxidase in patients Compare with control group as well as decreased transferrin and total iron binding capacity.

Intestinal parasitic infections and prevalence of anaemia among tribal school going children: a one year study

Background: Intestinal parasitic infections are one of the neglected tropical diseases listed by world health organization. Parasitic infections among school going tribal children cause significant anaemia and malnutrition. Our study mainly focused on estimating the prevalence of intestinal parasitic infections and focused on iron deficiency anaemia among the tribal school going children.Methods: A prospective study for one year was conducted at a tertiary care hospital and study group was tribal children from hostels and schools. Ethical committee approval was obtained and study included collection of socio demographic data, anthropometric data, stool examination for intestinal parasitic infections, Hb% estimation by “Hemocue globinometer Hb 301 System” a portable hemometer for Hb estimation. S. iron, S. transferrin and Total iron binding capacity were also estimated. Statistical analysis was performed by using SPSS version 20 and analyzed. P value &lt;0.05 was considered significant.Results: This 428 study participants with 66.36% boys and 33.64% girls were enrolled. The prevalence of parasitic infections was 42.06%. Protozoal infections were 41.11% when compared to helminthic infections (26.67%) and mixed infections in 32.22%. Entamoeba histolytica was the predominant protozoal parasite identified (30%) and Ascaris lumbricoides among the helminthic infection (13.3%). Presence of anaemia in the present study population was 11.21% and among the study group with parasitic infections it was 66.67%.Conclusion: To conclude, regular deworming practices, awareness regarding hand washing practices, iron and folic acid supplementation irrespective of nutritional status and health education could significantly reduce the incidence of anaemia associated with intestinal parasitic infections.

Novel anticancer PdII complexes: The effect of the conjugation of transferrin binding peptide and the nature of halogen coordinated on antitumor activity

A series of PdII complexes with bis-(2-pyridylmethyl)glycine as a ligand of formula [PdX(bis-(2-pyridylmethyl)glycine)] where X = Cl, Br, I were prepared and the effect of the halogen nature in the antitumor activity of eight tumorigenic and one non-tumorigenic cell line was evaluated. The chloride derivative was further functionalized with a transferrin receptor binding peptide, generating the first PdII based metallopeptide. Its antitumor activity was also evaluated. However, among all the complexes, the chloride and iodine parent compounds showed the lowest GI50 values in the panel evaluated, and lowest GI50 than cisplatin in several cell lines. In contrast, the bromine derivative showed higher values of GI50 than chloride and iodine (around 30 – 50 μM). The same trend was observed for the bovine serum albumin binding constant with higher values for iodine, chlorine, and bromine in this order. In aqueous solution, the chloride is exchanged by water while the bromine and iodine are not. DNA was evaluated as a target and showed no significative interaction for all the compounds. The results suggest sulfur-rich proteins and not DNA as a target. This report represents the first PdII metallopeptide reported, its evaluation in solution and antitumor activity. This work opens the possibilities for further functionalization of PdII complexes and the importance of the halogen coordination in the design of novel metallodrugs.