Interaction of polyacrylic acid coated and non-coated iron oxide nanoparticles with human neutrophils

Immunomodulatory bioadhesive technologies

Bioadhesives have found significant use in medicine and engineering, particularly for wound care, tissue engineering, and surgical applications. Compared to traditional wound closure methods such as sutures and staples, bioadhesives offer advantages, including reduced tissue damage, enhanced healing, and ease of implementation. Recent progress highlights the synergy of bioadhesives and immunoengineering strategies, leading to immunomodulatory bioadhesives capable of modulating immune responses at local sites where bioadhesives are applied. They foster favorable therapeutic outcomes such as reduced inflammation in wounds and implants or enhanced local immune responses to improve cancer therapy efficacy. The dual functionalities of bioadhesion and immunomodulation benefit wound management, tissue regeneration, implantable medical devices, and post-surgical cancer management. This review delves into the interplay between bioadhesion and immunomodulation, highlighting the mechanobiological coupling involved. Key areas of focus include the modulation of immune responses through chemical and physical strategies, as well as the application of these bioadhesives in wound healing and cancer treatment. Discussed are remaining challenges such as achieving long-term stability and effectiveness, necessitating further research to fully harness the clinical potential of immunomodulatory bioadhesives.

CO2 Adsorption by Carbon Quantum Dots/Metal Ferrites (M = Co2+, Ni2+, and Zn2+): Electrochemical and Theoretical Studies

In this study, we investigated the adsorption of CO2 by carbon quantum dot-based ferrites (MFe2O4, M = Co2+, Ni2+, and Zn2+) in the context of industrial CO2 emissions and global warming. The ferrites have been characterized using various analytical techniques [X-ray powder diffraction, FTIR, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS)], showing cubic spinel for CoFe2O4, reverse cubic spinel for NiFe2O4, and typical spinel for ZnFe2O4. A TGA study revealed a significant weight loss around 740-780 °C, indicating structural change occurred with increasing temperature. SEM and TEM images displayed spherical particles with sizes ranging from 10 to 50 nm. XPS confirmed the presence of C, O, and Fe atoms with specific cations (Co2+, Ni2+, and Zn2+). Electrochemical impedance Nyquist diagrams suggest a linear relationship between Z″ (ohm) and Z' (ohm) at low frequencies, but the semicircular loop obtained was significantly increased at higher frequencies. This suggests that the charge transfer resistance (R CT) at the electrode boundaries (interface) is much higher than at low frequencies, indicating the resistance per area was 1853 Ω cm2 for carbon paste electrodes (CPE)/CoFe2O4 and it decreased to 1652 Ω cm2 for CPE/NiFe2O4 and 1672 Ω cm2 for CPE/ZnFe2O4. However, improved electron transfer with lower resistance was seen due to the composite nature of the samples (CQDs@MFe2O4), revealing a lower resistance (1163 Ω cm2) for CQD@MFe2O4-CO2 as compared to 1567 Ω cm2 for MFe2O4. Thus, the adsorption of CO2 was studied electrochemically, and interaction between ferrates with CO2 was enhanced by the presence of CQDs in the samples. This is consistent with the adsorption of CO2 with the samples as it follows the Langmuir pseudo-second-order kinetics (k = 4.9, qe = 121.93 for CQD@CoFe2O4, k = 2.9, qe = 156.52 for CQD@NiFe2O4, and k = 3.0, qe = 141.71 for CQD@ZnFe2O4), and the data show that the adsorption efficiency has been decreased by around 1.0% after 7-8 cycles. Lastly, density functional theory analysis demonstrated the interaction of CO2 on the surface of the ferrites, deforming the CO2 linearity, which leads to a subsequent C-O interaction to form carbonate.

Combustion-derived carbon nanoparticles cause delayed apoptosis in neutrophil-like HL-60 cells in vitro and in primed human neutrophilic granulocytes ex vivo

BACKGROUND

Inhalation of combustion-derived nanoparticles may contribute to the development or exacerbation of inflammatory lung diseases by direct interaction with neutrophilic granulocytes. Earlier studies have shown that exposure of human neutrophils to carbon nanoparticles ex vivo causes a prolongation of cellular life by the reduction of apoptosis rates. Accordingly, reduced neutrophil apoptosis rates were observed in neutrophils from bronchoalveolar lavages from carbon nanoparticle-exposed animals. The current study describes molecular and cellular modes of action responsible for this proinflammatory effect.

RESULTS

Experiments with human blood neutrophils or neutrophil-like differentiated HL-60 cells exposed to carbon nanoparticles revealed dose dependent reduction of apoptosis rates. In both experimental systems, intracellular reactive oxygen species proved to be causally linked to this endpoint. Among the human samples, only primed cells from donors with slightly elevated proinflammatory plasma factors responded by delayed apoptosis. These neutrophils are characterized by an immunophenotype (CD16bright CD62Ldim) which is also observed in inflammatory lung diseases. Upon exposure to carbon nanoparticles these cells are further activated in an oxidant dependent manner. This activation appears to be linked to reduced apoptosis as samples with unchanged apoptosis rates were also not responding at this level. As reactive oxygen species triggered by carbon nanoparticles are known to cause membrane rearrangements, lipid raft structures were investigated by ganglioside M1 staining. Exposure of neutrophils resulted in a reduction of raft structures which could be prevented by an antioxidant strategy. The destruction of lipid rafts by depleting cholesterol also caused an activated immunophenotype and delayed apoptosis, indicating that membrane rearrangements after carbon nanoparticle exposure in primed neutrophils are responsible for cell activation and delayed apoptosis.

CONCLUSIONS

The antiapoptotic reactions observed in two independent experimental systems, differentiated neutrophil-like HL-60 cells and primed neutrophils, may be considered as additional proinflammatory effect of inhaled combustion-derived nanoparticles. Particularly in chronic diseases, which are characterized by neutrophilic lung inflammation, this effect can be expected to contribute to the deterioration of the health status. The data describe a mode of action in which intracellular reactive oxygen species cause membrane rearrangements that are responsible for neutrophil activation and delayed apoptosis.

PEG-Polymeric Nanocarriers Alleviate the Immunosuppressive Effects of Free 4-Thiazolidinone-Based Chemotherapeutics on T Lymphocyte Function and Cytokine Production

Purpose

Our study aimed to assess the effects of anticancer 4-thiazolidinone-based free water-insoluble therapeutics Les-3288 and Les-3833 and their waterborne complexes with branched PEG-containing polymeric carriers (A24-PEG550 and A24-PEG750) on immune response.

Methods

Human peripheral blood was used to study in vitro lymphocyte proliferative function, leukocyte phagocytic activity and respiratory burst, and cytokine production.

Results

The binding of the polymer to the anticancer drug Les-3288, which is intended to mitigate the immunosuppressive effects of the free drug on the proliferative activity of T lymphocytes and T-dependent B cells, demonstrated comparable efficacy for both A24-PEG750 and A24-PEG550 nanocarriers. Furthermore, it was observed that the drug-polymer complex significantly increased the reduced levels of IFN-γ and TNF-α resulting from free Les-3288. Conversely, the reduced levels of IL-6 and IL-4 remained unchanged. Administration of either form of Les-3288 had no effect on the phagocytic activity of monocytes, granulocytes or the respiratory burst of granulocytes. Due to the reduced cell viability and increased cytotoxicity associated with Les-3833, tenfold lower doses were selected for the immune assays. The effects of free Les-3833 on lymphocyte proliferative function resulted in significant stimulation of T-dependent B cells. The binding of Les-3833 to the smaller carrier, A24-PEG550 was found to maintain the stimulatory effect on B lymphocytes. While no effect of free Les-3833 on the granulocyte phagocytic activity was observed, binding of Les-3833 to both polymeric carriers resulted in a decrease in granulocyte phagocytic activity and respiratory burst, with no observable effect on monocytes. Monitoring of cytokine production showed no significant effect of either form of Les-3833 on the production of IFN-γ and IL-6. In the context of TNF-α and IL-4, the positive effect of polymer binding on restoring suppressed cytokine levels induced by the Les-3833 free drug was slightly more favorable for A24-PEG750.

Conclusion

The drug complexation with novel PEGylated carriers is a promising way for efficient therapeutic development.

Cytotoxic and radical activities of metal-organic framework modified with iron oxide: Biological and physico-chemical analyses

Metal-organic framework (MOF) modified with iron oxide, Fe3O4-MOF, is a perspective drug delivery agent, enabling magnetic control and production of active hydroxyl radicals, •OH, via the Fenton reaction. This paper studies cytotoxic and radical activities of Fe-containing nanoparticles (NPs): Fe3O4-MOF and its components - bare Fe3O4 and MOF (MIL-88B). Luminous marine bacteria Photobacteriumphosphoreum were used as a model cellular system to monitor bioeffects of the NPs. Neither the NPs of Fe3O4-MOF nor MOF showed cytotoxic effects in a wide range of concentrations (<10 mg/L); while Fe3O4 was toxic at >3·10-3 mg/L. The NPs of Fe3O4 did not affect the bacterial bioluminescence enzymatic system; their toxic effect was attributed to cellular membrane processes. The integral content of reactive oxygen species (ROS) was determined using a chemiluminescence luminol assay. Bacteria mitigated excess of ROS in water suspensions of Fe3O4-MOF and MOF, maintaining bioluminescence intensity closer to the control; this resulted in low toxicity of these NPs. We estimated the activity of •OH radicals in the NPs samples with physical and chemical methods - spin capture technology (using electron paramagnetic resonance spectroscopy) and methylene blue degradation. Physico-chemical interpretation of cellular responses is provided in terms of iron content, iron ions release and •OH radical production.

The effects of iron oxide nanoparticles on antioxidant capacity and response to oxidative stress in Mozambique tilapia (Oreochromis mossambicus, Peters 1852)

Recent research has raised concern about the biocompatibility of iron oxide nanoparticles (IONPs), as they have been reported to induce oxidative stress and inflammatory responses, whilst prolonged exposure to high IONP concentrations may lead to cyto-/genotoxicity. Besides, there is concern about its environmental impact. The aim of our study was to investigate the effects of IONPs on the antioxidant defence system in freshwater fish Mozambique tilapia (Oreochromis mossambicus, Peters 1852). The fish were exposed to IONP concentration of 15 mg/L over 1, 3, 4, 15, 30, and 60 days and the findings compared to a control, unexposed group. In addition, we followed up the fish for 60 days after exposure had stopped to estimate the stability of oxidative stress induced by IONPs. Exposure affected the activity of antioxidant and marker enzymes and increased the levels of hydrogen peroxide and lipid peroxidation in the gill, liver, and brain tissues of the fish. Even after 60 days of depuration, adverse effects remained, indicating long-term nanotoxicity. Moreover, IONPs accumulated in the gill, liver, and brain tissues. Our findings underscore the potential health risks posed to non-target organisms in the environment, and it is imperative to establish appropriate guidelines for safe handling and disposal of IONPs to protect the aquatic environment.

Impact of gold nanoparticles (AuNPs) in human neutrophils in vitro and in leukocytes attraction in vivo: A sex-based analysis

Some differences exist between the male and female immune systems. Despite this, a sex-based analysis is not frequently performed in most studies. Knowing that inflammation is a common undesired effect observed resulting from nanoparticle (NP) exposure, we investigate here how gold NPs with a primary size of 20 (AuNP20) and 70 nm (AuNP70) will alter the biology of polymorphonuclear neutrophil cells (PMNs) isolated from men and women as well as their potential pro-inflammatory effect in vivo in male and female mice. We found that AuNP20 significantly delay apoptosis only in PMN isolated from men. The production of interleukin (IL)- 8 by PMNs was increased by both AuNPs regardless of sex although significance was only observed in AuNP20-induced PMNs. Using the murine air pouch model of inflammation, AuNPs did not induce a neutrophilic infiltration regardless of sex. In conclusion, AuNPs could differently alter the biology of PMNs according to sex.

Interaction between iron oxide nanoparticles (IONs) and primary human immune cells: An up-to-date review of the literature

Nanotechnology has been gaining more and more momentum lately and the potential use of nanomaterials such as nanoparticles (NPs) continues to grow in a variety of activity sectors. Among the NPs, iron oxide nanoparticles (IONs) have retained an increasing interest from the scientific community and industrials due to their superparamagnetic properties allowing their use in many fields, including medicine. However, some undesired effects of IONs and potential risk for human health are becoming increasingly reported in several studies. Although many in vivo studies reported that IONs induce immunotoxicity in different animal models, it is not clear how IONs can alter the biology of primary human immune cells. In this article, we will review the works that have been done regarding the interaction between IONs and primary immune cells. This review also outlines the importance of using primary immune cells in risk assessment of NPs as a reliable strategy for encouraging non-animal studies approaches, to determine risks that might affect the human immune system following different exposure scenarios. Taken all together, the reported observations help to get a more global picture on how IONs alter the human immune system especially the fact that inflammation, known to involve several immune cell types, is frequently reported as an undesired effect of IONs.

Remodeling the hepatic fibrotic microenvironment with emerging nanotherapeutics: a comprehensive review

Liver fibrosis could be the last hope for treating liver cancer and remodeling of the hepatic microenvironment has emerged as a strategy to promote the ablation of liver fibrosis. In recent years, especially with the rapid development of nanomedicine, hepatic microenvironment therapy has been widely researched in studies concerning liver cancer and fibrosis. In this comprehensive review, we summarized recent advances in nano therapy-based remodeling of the hepatic microenvironment. Firstly, we discussed novel strategies for regulatory immune suppression caused by capillarization of liver sinusoidal endothelial cells (LSECs) and macrophage polarization. Furthermore, metabolic reprogramming and extracellular matrix (ECM) deposition are caused by the activation of hepatic stellate cells (HSCs). In addition, recent advances in ROS, hypoxia, and impaired vascular remodeling in the hepatic fibrotic microenvironment due to ECM deposition have also been summarized. Finally, emerging nanotherapeutic approaches based on correlated signals were discussed in this review. We have proposed novel strategies such as engineered nanotherapeutics targeting antigen-presenting cells (APCs) or direct targeting T cells in liver fibrotic immunotherapy to be used in preventing liver fibrosis. In summary, this comprehensive review illustrated the opportunities in drug targeting and nanomedicine, and the current challenges to be addressed.

Comparative study on effects of pH, electrolytes, and humic acid on the stability of acetic and polyacrylic acid coated magnetite nanoparticles

The poor colloidal stability of magnetite nanoparticles (MNPs) limits their mobility and application, so various organic coatings (OCs) were applied to MNPs. Here, a comparative study on the colloidal stability of MNPs coated with acetic (HAc) and polyacrylic acids (PAA) was conducted under varied pH (5.0-9.0) in the presence of different concentrations of cations and anions, as well as humic acid (HA). Comparing the effects of various cations and anions, the stability of both HAc/PAA-MNPs followed the order: Na⁺ > Ca²⁺and PO₄^3- > SO₄^2- > Cl^-, which could be explained by their adsorption behaviors onto HAc/PAA-MNPs and the resulting surface charge changes. Under all conditions even with more anion adsorption onto HAc-MNPs (0.14-22.56 mg/g) than onto PAA-MNPs (0.04-18.34 mg/g), PAA-MNPs were more negatively charged than HAc-MNPs, as PAA has a lower pH_IEP (2.6 ± 0.1) than that of HAc (3.7 ± 0.1). Neither the HAc nor PAA coatings were displaced by phosphate even at considerably high phosphate concentration. Compared with HAc-MNPs, the stability of PAA-MNPs was greatly improved under all studied conditions, which could be due to both stronger electrostatic and additional steric repulsion forces among PAA-MNPs. Besides, under all conditions, Derjaguin-Landau-Verwey-Overbeek (DLVO) explained well the aggregation kinetic of HAc-MNPs; while extended DLVO (EDLVO) successfully predict that of PAA-MNPs, indicating steric forces among PAA-MNPs. The aggregation of HAc/PAA-MNPs was all inhibited in varied electrolyte solutions by HA (2 mg C/L) addition. This study suggested that carboxyl coatings with higher molecular weights and pK_a values could stabilize MNPs better due to stronger electrostatic and additional steric repulsion. However, in the presence of HA, these two forces were mainly controlled by adsorbed HA instead of the organic pre-coatings on MNPs.

Polypropylene nanoplastic exposure leads to lung inflammation through p38-mediated NF-κB pathway due to mitochondrial damage

BACKGROUND

Polypropylene (PP) is used in various products such as disposable containers, spoons, and automobile parts. The disposable masks used for COVID-19 prevention mainly comprise PP, and the disposal of such masks is concerning because of the potential environmental pollution. Recent reports have suggested that weathered PP microparticles can be inhaled, however, the inhalation toxicology of PP microparticles is poorly understood.

RESULTS

Inflammatory cell numbers, reactive oxygen species (ROS) production, and the levels of inflammatory cytokines and chemokines in PP-instilled mice (2.5 or 5 mg/kg) increased significantly compared to with those in the control. Histopathological analysis of the lung tissue of PP-stimulated mice revealed lung injuries, including the infiltration of inflammatory cells into the perivascular/parenchymal space, alveolar epithelial hyperplasia, and foamy macrophage aggregates. The in vitro study indicated that PP stimulation causes mitochondrial dysfunction including mitochondrial depolarization and decreased adenosine triphosphate (ATP) levels. PP stimulation led to cytotoxicity, ROS production, increase of inflammatory cytokines, and cell deaths in A549 cells. The results showed that PP stimulation increased the p-p38 and p-NF-κB protein levels both in vivo and in vitro, while p-ERK and p-JNK remained unchanged. Interestingly, the cytotoxicity that was induced by PP exposure was regulated by p38 and ROS inhibition in A549 cells.

CONCLUSIONS

These results suggest that PP stimulation may contribute to inflammation pathogenesis via the p38 phosphorylation-mediated NF-κB pathway as a result of mitochondrial damage.

Crystal Plane Impact of ZnFe2O4-Ag Nanoparticles Influencing Photocatalytical and Antibacterial Properties: Experimental and Theoretical Studies

This paper describes the crystal interphase impact of ZnFe₂O₄-Ag in the photodegradation of Rhodamine B. Prepared ZnFe₂O₄ nanoparticles (NPs) were deposited with Ag NPs to offer ZnFe₂O₄-Ag (0-2.5%). An X-ray diffraction peak corresponding to the Ag NPs was detected if the particle content reached about 2.0%, observing multiple crystalline interphases in HR-TEM. Magnetic saturation (Ms) was increased ∼160% times for ZnFe₂O₄-Ag (7.25 to 18.71 emu/g) and ZnFe₂O₄ (9.62 to 25.09 emu/g) if the temperature is lowered from 298 to 5.0 K; while for Fe₃O₄ (91.09 to 96.19 emu/g), the Ms increment was just about 5.6%. After analyzing the DFT-Density of State, a decrease of bandgap energy for ZnFe₂O₄-Ag₆ from the influence of the size of Ag cluster was seen. Quantum yield (Φ) was 0.60 for ZnFe₂O₄, 0.25 for ZnFe₂O₄-Ag (1.0%), 0.70 for ZnFe₂O₄-Ag (1.5%), 0.66 for ZnFe₂O₄-Ag (2.0%), and 0.66 for ZnFe₂O₄-Ag (2.5%), showing that the disposition of Ag NPs (1.5-2.5%) increases the Φ to >0.60. The samples were used to photo-oxidize RhB under visible light assisted by photopowered Langmuir adsorption. The degradation follows first-order kinetics (k = 5.5 × 10^-3 min^-1), resulting in a greater k = 2.0 × 10^-3 min^-1 for ZnFe₂O₄-Ag than for ZnFe₂O₄ (or Fe₃O₄, k = 1.1 × 10^-3 min^-1). DFT-total energy was used to analyze the intermediates formed from the RhB oxidation. Finally, the ZnFe₂O₄-Ag exhibits good antibacterial behavior because of the presence of Zn and the Ag components.

Interaction between iron oxide nanoparticles (Fe3O4 NPs) and human neutrophils: Evidence that Fe3O4 NPs possess some pro-inflammatory activities

Iron oxide nanoparticles (Fe₃O₄ NPs) are important for different medical applications. However, potential toxicity has been reported and several parameters must still be studied to reach highest therapeutic efficacy with minimal undesired effects. Inflammation is one of the most reported undesired effects of NP exposure in a variety of inflammatory models and conflicting data exist regarding whether Fe₃O₄ NPs possess pro- or anti-inflammatory activities. The aim of this study was to determine the direct effect of Fe₃O₄ NPs on the biology of neutrophil, a key player cell in inflammation. Freshly isolated human neutrophils were incubated in vitro with Fe₃O₄ NPs, and several functions have been studied. Using transmission electronic microscopy, Fe₃O₄ NPs were found to be ingested by neutrophils. These NPs do not induce a respiratory burst by themselves, but they increase the ability of neutrophils to adhere onto human endothelial cells as well as enhance phagocytosis. An antibody array approach revealed that Fe₃O₄ NPs induce the production of some cytokines, including the chemokine IL-8 (CXCL8), which was confirmed by ELISA. Fe₃O₄NPs were found to delay spontaneous neutrophil apoptosis regardless of sex of the donor. Using a pharmacological approach, we demonstrate that Fe₃O₄ NPs delay apoptosis by a de novo protein synthesis-dependent mechanism and via different cell signalling pathways. The data indicate that Fe₃O₄ NPs can alter the biology of human neutrophils and that they possess some pro-inflammatory effects, particularly based on their capacity to delay apoptosis and to induce the production of pro-inflammatory cytokines. Therefore, Fe₃O₄ NPs can regulate inflammation by targeting human neutrophil functions.

Polyacrylic Acid Nanoplatforms: Antimicrobial, Tissue Engineering, and Cancer Theranostic Applications

Polyacrylic acid (PAA) is a non-toxic, biocompatible, and biodegradable polymer that gained lots of interest in recent years. PAA nano-derivatives can be obtained by chemical modification of carboxyl groups with superior chemical properties in comparison to unmodified PAA. For example, nano-particles produced from PAA derivatives can be used to deliver drugs due to their stability and biocompatibility. PAA and its nanoconjugates could also be regarded as stimuli-responsive platforms that make them ideal for drug delivery and antimicrobial applications. These properties make PAA a good candidate for conventional and novel drug carrier systems. Here, we started with synthesis approaches, structure characteristics, and other architectures of PAA nanoplatforms. Then, different conjugations of PAA/nanostructures and their potential in various fields of nanomedicine such as antimicrobial, anticancer, imaging, biosensor, and tissue engineering were discussed. Finally, biocompatibility and challenges of PAA nanoplatforms were highlighted. This review will provide fundamental knowledge and current information connected to the PAA nanoplatforms and their applications in biological fields for a broad audience of researchers, engineers, and newcomers. In this light, PAA nanoplatforms could have great potential for the research and development of new nano vaccines and nano drugs in the future.

Exploiting the Potential of Supported Magnetic Nanomaterials as Fenton-Like Catalysts for Environmental Applications

In recent years, the application of magnetic nanoparticles as alternative catalysts to conventional Fenton processes has been investigated for the removal of emerging pollutants in wastewater. While this type of catalyst reduces the release of iron hydroxides with the treated effluent, it also presents certain disadvantages, such as slower reaction kinetics associated with the availability of iron and mass transfer limitations. To overcome these drawbacks, the functionalization of the nanocatalyst surface through the addition of coatings such as polyacrylic acid (PAA) and their immobilization on a mesoporous silica matrix (SBA15) can be factors that improve the dispersion and stability of the nanoparticles. Under these premises, the performance of the nanoparticle coating and nanoparticle-mesoporous matrix binomials in the degradation of dyes as examples of recalcitrant compounds were evaluated. Based on the outcomes of dye degradation by the different functionalized nanocatalysts and nanocomposites, the nanoparticles embedded in a mesoporous matrix were applied for the removal of estrogens (E1, E2, EE2), accomplishing high removal percentages (above 90%) after the optimization of the operational variables. With the feasibility of their recovery in mind, the nanostructured materials represented a significant advantage as their magnetic character allows their separation for reuse in different successive sequential batch cycles.

Evaluating the Apoptotic Cell Death Modulatory Activity of Nanoparticles in Men and Women Neutrophils and Eosinophils

Apoptosis is an important cell death mechanism for the resolution of inflammation. Neutrophil spontaneous apoptosis rates were reported to be slightly different in men and women and to be modulated by female sex hormones. The aim of this study was to determine whether different nanoparticles (NPs) will alter the neutrophil and eosinophil apoptotic rates differently in men and women. Using the antiapoptotic cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) and the proapoptotic plant lectin Viscum album agglutinin-I (VAA-I) as controls, we found that these factors respectively delay and induce apoptosis in both neutrophils and eosinophils with apoptotic rates remarkably similar in both sexes. The polyamidoamine (PAMAM) dendrimers of generation 0 (G0) and G3 slightly, but not significantly, accelerate neutrophil apoptosis regardless of sex. Zinc oxide (ZnO), titanium dioxide (TiO₂), cerium dioxide (CeO₂), and palladium (Pd) but not platinum (Pt) NPs were found to significantly delay neutrophil apoptosis. When results were compared between men and women, only ZnO and Pd NPs were found to significantly delay neutrophil apoptosis in men while ZnO, TiO₂, CeO₂, and Pt NPs inhibit apoptosis in women neutrophils. In eosinophils, G3, but not G0 NPs, significantly accelerate apoptosis in women. ZnO, Pt, and Pd NPs significantly delay eosinophil apoptosis but only in women. Unlike neutrophils, TiO₂ and CeO₂ NPs did not significantly delay eosinophil apoptosis. We propose that future studies aiming at determining potential effect NPs on cellular biological processes should incorporate a sex-based analysis based on the differences reported here studying the impact of NPs on human granulocyte apoptosis.

Immunocompatibility of a new dual modality contrast agent based on radiolabeled iron-oxide nanoparticles

Radiolabeled magnetic nanoparticles are promising candidates as dual-modality-contrast-agents (DMCA) for diagnostic applications. The immunocompatibility of a new DMCA is a prerequisite for subsequent in vivo applications. Here, a new DMCA, namely Fe3O4 nanoparticles radiolabeled with 68Ga, is subjected to immunocompatibility tests both in vitro and in vivo. The in vitro immunocompatibility of the DMCA relied on incubation with donated human WBCs and PLTs (five healthy individuals). Optical microscopy (OM) and atomic force microscopy (AFM) were employed for the investigation of the morphological characteristics of WBCs and PLTs. A standard hematology analyzer (HA) provided information on complete blood count. The in vivo immunocompatibility of the DMCA was assessed through its biodistribution among the basic organs of the mononuclear phagocyte system in normal and immunodeficient mice (nine in each group). In addition, Magnetic Resonance Imaging (MRI) data were acquired in normal mice (three). The combined OM, AFM and HA in vitro data showed that although the DMCA promoted noticeable activation of WBCs and PLTs, neither degradation nor clustering were observed. The in vivo data showed no difference of the DMCA biodistribution between the normal and immunodeficient mice, while the MRI data prove the efficacy of the particular DMCA when compared to the non-radiolabeled, parent CA. The combined in vitro and in vivo data prove that the particular DMCA is a promising candidate for future in vivo applications.

Neutrophil and Nanoparticles Delivery to Tumor: Is It Going to Carry That Weight?

The application of cell carriers for transporting nanodrugs to the tumor draws much attention as the alternative to the passive drug delivery. In this concept, the neutrophil (NΦ) is of special interest as this cell is able to uptake nanoparticles (NPs) and cross the vascular barrier in response to tumor signaling. There is a growing body of literature describing NP-NΦ interactions in vitro and in vivo that demonstrates the opportunity of using these cells to improve the efficacy of cancer therapy. However, a number of conceptual and technical issues need to be resolved for translating the technology into clinics. The current review summarizes the recent advances and challenges associated with NP-NΦ interactions, with the special focus on the complex interplay between the NP internalization pathways and the modulation of NΦ activity, and its potential consequences for nanodrug delivery.

One-spot fabrication and in-vivo toxicity evaluation of core-shell magnetic nanoparticles

This research, for the first time, report the synthesis of core-shell magnetic nanoparticles (NPs) consisting poly acrylic acid (PAA) coated cobalt ferrite (CF) using a simple co-precipitation route. Nanocrystalline PAA@CF-NPs, particle size of 9.2 nm, exhibited saturation magnetization as 28.9 emu/g, remnant magnetization as 8.37 emu/g, and coercivity as 543 Oe. Keeping biomedical applications into consideration, PAA@CF-NPs were further analysed to evaluate antimicrobial performance against Gram positive (Staphylococcus aureus and Bacillus subtilis) and Gram negative (Pseudomonas aeruginosa and Escherichia coli) bacteria, and biocompatibility with reference to activated splenic cells. The PAA@CF-NPs were viable to the normal splenic cells (up to 1000 μg/ml) and do not affect the ability of fast dividing ability of the cells (activated splenic cells). An optimized dose of PAA@CF-NPs was intramuscularly administrated (100 μg/ml) into Albino mice to evaluate acute toxicity. The results of these studies suggest that injected PAA@CF-NPs do not affect vital organs mainly including liver and kidneys that confirmed the heptic/renal biocompatibility. The outcomes of this research project such developed nano-system for biomedical applications, mainly for magnetically guided drug delivery and image guided therapies development. However, to support the proposed claims, extended in-vivo studies are required to explore bio-distribution, chronic toxicity, and homeostatic conditions.

Neutrophil Inflammatory Response Is Downregulated by Uptake of Superparamagnetic Iron Oxide Nanoparticle Therapeutics

Superparamagnetic iron oxide nanoparticles (SPION) are employed as diagnostics and therapeutics following intravenous delivery for the treatment of iron deficiency anemia (IDA) in adult patients with chronic kidney failure. Neutrophils are the first defense against blood borne foreign insult and recruit to vascular sites of inflammation via a sequential process that is characterized by adhesive capture, rolling, and shear resistant arrest. A primary chemotactic agonist presented on the glycocalyx of inflamed endothelium is IL-8, which upon binding to its cognate membrane receptor (CXCR1/2) activates a suite of responses in neutrophils. An early response is degranulation with accompanying upregulation of β2-integrin (CD11/CD18) and shedding of L-selectin (CD62L) receptors, which exert differential effects on the efficiency of endothelial recruitment. Feraheme is an FDA approved SPION treatment for IDA, but its effect on the innate immune response of neutrophils during inflammation has not been reported. Here, we studied the immunomodulatory effects of Feraheme on neutrophils freshly isolated from healthy human subjects and stimulated in suspension or on inflammatory mimetic substrates with IL-8. Cells treated with Feraheme exhibited reduced sensitivity to stimulation with IL-8, indicated by reduced upregulation of membrane CD11b/CD18 receptors, high affinity (HA) CD18, and shedding of CD62L. Feraheme also inhibited N-formyl-Met-Leu-Phe (fMLP) induced reactive oxygen species production. Neutrophil rolling, arrest, and migration was assessed in vascular mimetic microfluidic channels coated with E-selectin and ICAM-1 to simulate inflamed endothelium. Neutrophils exposed to Feraheme rolled faster on E-selectin and arrested less frequently on ICAM-1, in a manner dependent upon SPION concentration. Subsequent neutrophil shape change, and migration were also significantly inhibited in the presence of Feraheme. Lastly, Feraheme accelerated clearance of cytosolic calcium flux following IL-8 stimulation. We conclude that uptake of Feraheme by neutrophils inhibits chemotactic activation and downregulates normal rolling to arrest under shear flow. The mechanism involves increased calcium clearance following chemotactic activation, which may diminish the efficiency of recruitment from the circulation at vascular sites of inflammation.

Metal-derived nanoparticles in tumor theranostics: Potential and limitations

Initially, metal derived nanoparticles have been used exclusively as contrasting agents in magnetic resonance imaging. Today, green routes of chemical synthesis together with numerous modifications of the core and surface gave rise to a plethora of biomedical applications of metal derived nanoparticles including tumor imaging, diagnostics, and therapy. These materials are an emerging class of tools for tumor theranostics. Nevertheless, the spectrum of clinically approved metal nanoparticles remains narrow, as the safety, specificity and efficiency still have to be improved. In this review we summarize the major directions for development and biomedical applications of metal based nanoparticles and analyze their effects on tumor cells and microenvironment. We discuss the advantages and possible limitations of metal nanoparticle-based tumor theranostics, as well as the potential strategies to improve the in vivo performance of these unique materials.

Rat Blood Leukocytes after Intravenous Injection of Chitosan-Modified Magnetic Nanospheres

Nanosized magnetite particles (magnetic nanospheres) are a prospective basis for creation of new diagnostic and therapeutic agents. The structure of blood leukocytes and the leukocytic formula are studied in adult rats over a period of 120 days after a single intravenous injection of chitosan-modified nanosized magnetite particles. No effects of chitosan-modified magnetic nanospheres on the structure of rat blood leukocytes are detected. Injection of suspension of chitosan-modified magnetite nanospheres is associated with an increase in the levels of monocytes, segmented and stab neutrophils, and a decrease in lymphocyte counts in the blood of rats. The shifts in the leukogram parameters are transitory, the picture returned to normal by day 40 postinjection.

Methods of Granulocyte Isolation from Human Blood and Labeling with Multimodal Superparamagnetic Iron Oxide Nanoparticles

This in vitro study aimed to find the best method of granulocyte isolation for subsequent labeling with multimodal nanoparticles (magnetic and fluorescent properties) to enable detection by optical and magnetic resonance imaging (MRI) techniques. The granulocytes were obtained from venous blood samples from 12 healthy volunteers. To achieve high purity and yield, four different methods of granulocyte isolation were evaluated. The isolated granulocytes were labeled with multimodal superparamagnetic iron oxide nanoparticles (M-SPIONs) coated with dextran, and the iron load was evaluated qualitatively and quantitatively by MRI, near-infrared fluorescence (NIRF) and inductively coupled plasma mass spectrometry (ICP-MS). The best method of granulocyte isolation was Percoll with Ficoll, which showed 95.92% purity and 94% viability. After labeling with M-SPIONs, the granulocytes showed 98.0% purity with a yield of 3.5 × 10⁶ cells/mL and more than 98.6% viability. The iron-loading value in the labeled granulocytes, as obtained by MRI, was 6.40 ± 0.18 pg/cell. Similar values were found with the ICP-MS and NIRF imaging techniques. Therefore, our study shows that it is possible to isolate granulocytes with high purity and yield and labeling with M-SPIONs provides a high internalized iron load and low toxicity to cells. Therefore, these M-SPION-labeled granulocytes could be a promising candidate for future use in inflammation/infection detection by optical and MRI techniques.

Polyacrylic acid-coated iron oxide nanoparticles could be a useful tool for tracking inflammatory monocytes

Aim:

To establish the effect of poly(acrylic acid)-coated iron oxide nanoparticles (PAC-IONs) and later exposure to a magnetic field on the differentiation of mononuclear phagocytes into macrophages.

Methods:

By flow cytometry, cell death was evaluated with DIOC6 and PI, Poly (ADP-ribose) Polymerases (PARP) fragmentation, H2AX phosphorylation and TUNEL assay. Cytokines by Cytokine bead array and the intracellular amount of iron by atomic absorption spectrometry.

Results:

PAC-IONs did not induce apoptosis, modify the cell membrane integrity or alter the mitochondrial membrane potential. They did not affect the cell morphology, the pattern of cytokine accumulation or the activating role of differentiation of mononuclear phagocytes into macrophages on the proliferation of autologous T cells.

Conclusion:

This evidence indicates that the PAC-IONs are safe and biocompatible. Moreover, the selectivity of the PAC-IONs for mononuclear phagocytes, as well as their increased uptake by non-classical monocytes, warrant future research with a view to their use as a contrast agent, a useful tool for in vivo tracking of tissue-infiltrating mononuclear phagocytes.

In the search for materials that allow the study of inflammatory processes when biopsies are not feasible, magnetic nanoparticles have become an alternative tool for use in MRI. This article examined whether supermagnetic iron nanoparticles can affect the basic function of phagocytic cells, with a view to their use in clinical imaging applications.

Adoption of in vitro systems and zebrafish embryos as alternative models for reducing rodent use in assessments of immunological and oxidative stress responses to nanomaterials

Assessing the safety of engineered nanomaterials (NMs) is paramount to the responsible and sustainable development of nanotechnology, which provides huge societal benefits. Currently, there is no evidence that engineered NMs cause detrimental health effects in humans. However, investigation of NM toxicity using in vivo, in vitro, in chemico, and in silico models has demonstrated that some NMs stimulate oxidative stress and inflammation, which may lead to adverse health effects. Accordingly, investigation of these responses currently dominates NM safety assessments. There is a need to reduce reliance on rodent testing in nanotoxicology for ethical, financial and legislative reasons, and due to evidence that rodent models do not always predict the human response. We advocate that in vitro models and zebrafish embryos should have greater prominence in screening for NM safety, to better align nanotoxicology with the 3Rs principles. Zebrafish are accepted for use by regulatory agencies in chemical safety assessments (e.g. developmental biology) and there is growing acceptance of their use in biomedical research, providing strong foundations for their use in nanotoxicology. We suggest that investigation of the response of phagocytic cells (e.g. neutrophils, macrophages) in vitro should also form a key part of NM safety assessments, due to their prominent role in the first line of defense. The development of a tiered testing strategy for NM hazard assessment that promotes the more widespread adoption of non-rodent, alternative models and focuses on investigation of inflammation and oxidative stress could make nanotoxicology testing more ethical, relevant, and cost and time efficient.

WITHDRAWN: Titanium dioxide nanoparticles induce human eosinophil adhesion onto endothelial EA.hy926 cells via activation of phosphoinositide 3-kinase/Akt cell signalling pathway

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Quantitative histochemistry for macrophage biodistribution on mice liver and spleen after the administration of a pharmacological-relevant dose of polyacrylic acid-coated iron oxide nanoparticles

Understanding in vivo biodistribution of iron oxide nanoparticles (IONs), and the involvement of the phagocyte system in this process, is crucial for the assessment of their potential health risk. In the present study, the histochemical expression of iron in liver and spleen sections of CD-1 mice (aged 8 weeks) was quantified, 24 h after intravenous administration of polyacrylic acid-coated IONs (PAA-coated IONs) (8, 20, 50 mg/kg). Organ sections were stained with Perls' Prussian blue for iron detection, followed by the quantification of iron deposition with ImageJ software. Our study revealed the existence of a linear dose-dependent increase of iron deposition in macrophages of both organs. Exposed animals showed hepatic iron deposition in all zones, although most marked in periportal region. In the spleen, no iron was detected in the white splenic pulp of both control and treated animals. When compared with control mice, a positive correlation between histochemical detection of iron and PAA-coated ION doses was observed in splenic red pulp of animals. The results confirmed our assumption that liver and spleen are involved in the clearance pathways of PAA-coated IONs from the blood. Excess iron was cytotoxic at the highest dose of PAA-coated IONs tested, but no significant morphologic alterations were observed for the lower doses. Clusters of early necrotic hepatocytes were observed in the hepatic periportal region of mice injected with the higher dose (50 mg/kg) of PAA-coated IONs. Further studies are necessary to determine if liver and spleen macrophages will degrade these IONs, or eventually exocytose both the degraded and intact ones.

Deleterious effects in reproduction and developmental immunity elicited by pulmonary iron oxide nanoparticles

With the extensive application of iron oxide nanoparticles (FeNPs), attention about their potential risks to human health is also rapidly raising, particularly in sensitive subgroups such as pregnant women and babies. In this study, we a single instilled intratracheally FeNPs (1, 2, and 4mg/kg) to the male and female parent mice, mated, then assessed reproductive toxicity according to the modified OECD TG 421. During the pre-mating period (14 days), two female parent mice died at 4mg/kg dose, and the body weight gain dose-dependently decreased in male and female parent mice exposed to FeNPs. Additionally, iron accumulation and the enhanced expression of MHC class II molecules were observed in the ovary and the testis of parent mice exposed to the highest dose of FeNPs, and the total sex ratio (male/female) of the offspring mice increased in the groups exposed to FeNPs. Following, we a single instilled intratracheally to their offspring mice with the same doses and evaluated the immunotoxic response on day 28. The increased mortality and significant hematological- and biochemical- changes were observed in offspring mice exposed at 4mg/kg dose, especially in female mice. More interestingly, balance of the immune response was shifted to a different direction in male and female offspring mice. Taken together, we conclude that the NOAEL for reproductive and developmental toxicity of FeNPs may be lower than 2mg/kg, and that female mice may show more sensitive response to FeNPs exposure than male mice. Furthermore, we suggest that further studies are necessary to identify causes of both the alteration in sex ratio of offspring mice and different immune response in male and female offspring mice.

Are iron oxide nanoparticles safe? Current knowledge and future perspectives

Due to their unique physicochemical properties, including superparamagnetism, iron oxide nanoparticles (ION) have a number of interesting applications, especially in the biomedical field, that make them one of the most fascinating nanomaterials. They are used as contrast agents for magnetic resonance imaging, in targeted drug delivery, and for induced hyperthermia cancer treatments. Together with these valuable uses, concerns regarding the onset of unexpected adverse health effects following exposure have been also raised. Nevertheless, despite the numerous ION purposes being explored, currently available information on their potential toxicity is still scarce and controversial data have been reported. Although ION have traditionally been considered as biocompatible - mainly on the basis of viability tests results - influence of nanoparticle surface coating, size, or dose, and of other experimental factors such as treatment time or cell type, has been demonstrated to be important for ION in vitro toxicity manifestation. In vivo studies have shown distribution of ION to different tissues and organs, including brain after passing the blood-brain barrier; nevertheless results from acute toxicity, genotoxicity, immunotoxicity, neurotoxicity and reproductive toxicity investigations in different animal models do not provide a clear overview on ION safety yet, and epidemiological studies are almost inexistent. Much work has still to be done to fully understand how these nanomaterials interact with cellular systems and what, if any, potential adverse health consequences can derive from ION exposure.

Biodistribution of polyacrylic acid-coated iron oxide nanoparticles is associated with proinflammatory activation and liver toxicity

Iron oxide nanoparticles (IONs) have physical and chemical properties that render them useful for several new biomedical applications. Still, so far, in vivo safety studies of IONs with coatings of biomedical interest are still scarce. The aim of this study, therefore, was to clarify the acute biological effects of polyacrylic acid (PAA)-coated IONs, by determining their biodistribution and their potential proinflammatory and toxic effects in CD-1 mice. The biodistribution of PAA-coated IONs in several organs (liver, spleen, kidneys, brain, heart, testes and lungs), the plasma cytokines, chemokine and aminotransferases levels, white blood cell count, oxidative stress parameters, adenosine triphosphate and histologic features of liver, spleen and kidneys were evaluated 24 h after a single acute (8, 20 or 50 mg kg(-1) ) intravenous administration of PAA-coated IONs in magnetite form. The obtained results showed that these IONs accumulate mainly in the liver and spleen and, to a lesser extent, in the lungs. Although our data showed that PAA-coated IONs do not cause severe organ damage, an inflammatory process was triggered in vivo, as evidenced by as evidenced by increased neutrophils and large lymphocytes in the differential blood count. Moreover, an accumulation of iron in macrophages of the liver and spleen was observed and hepatic lipid peroxidation was elicited, showing that the IONs are able to induce oxidative stress. The effects of these nanoparticles need to be further investigated regarding the mechanisms involved and the long-term consequences of intravenous administration of PAA-coated IONs. Copyright © 2016 John Wiley & Sons, Ltd.

Rapid and efficient magnetization of mesenchymal stem cells by dendrimer-functionalized magnetic nanoparticles

Aim: Rapid and efficient magnetization of human bone marrow stromal cells (BMSC) through functionalized magnetic nanoparticles (MNP). Methods: MNP were functionalized with poly(epsilon-lysine) dendrons exposing carboxybetaine residue (CB-MNP) to enhance binding to the cellular glycocalix. BMSC were incubated with CB-MNP or non-functionalized PAA-MNP for 5–30 min in suspension. Results: CB-MNP functionalization increased the magnetization efficiency by threefold. Remarkably, 66% of cells were magnetized after only 5 min and the maximum efficiency of >80% was reached by 15 min. BMSC viability, proliferation and differentiation were not impaired: actually, adipogenic and osteogenic differentiation were even improved. Conclusion: Carboxybetaine-dendron functionalization ensured rapid and efficient BMSC magnetization and allowed innovative suspension labeling, with a potential for bypassing adhesion culture of progenitors for regenerative medicine.

Facile synthesis of novel hydrophilic and carboxyl-amine functionalized superparamagnetic iron oxide nanoparticles for biomedical applications

We report a one-step facile synthesis of novel water-soluble and functionalized SPIONs, which could be promising candidates for cancer theranostics.

Silver nanoparticles of 70 nm and 20 nm affect differently the biology of human neutrophils

The influence of size of nanoparticles (NP), especially in regard to pulmonary toxicity, has been widely investigated. In general, NP with smaller diameters are more pro-inflammatory in vivo, at least in terms of neutrophil influx. Nevertheless, the influence of size of NP on polymorphonuclear neutrophil (PMN) cell biology is poorly documented. In the study here, it was decided to determine if AgNP with a diameter of 70 nm (AgNP70) will alter the biology of human PMN similarly to AgNP20 previously reported to induce apoptosis and inhibit de novo protein synthesis. The results here indicated that, in contrast to AgNP20, AgNP70 delayed PMN apoptosis. However, both AgNP20 and AgNP70 inhibited de novo protein synthesis. Both forms of AgNP did not significantly increase reactive oxygen species (ROS) production, but AgNP20 significantly increased the cell production of the CXCL8 chemokine (IL-8). In addition, AgNP20, but not AgNP70, induced the release of albumin and matrix metalloproteinase-9 (MMP-9/gelatinase B) into culture supernatants. Consistent with this latter observation, gelatinase activity was increased by AgNP20, as assessed by zymography. From these outcomes, it is concluded that two NP with different initial diameters can possess similar - as well as distinct - biological properties in modulating human PMN functions. These outcomes are testimony to the complexity of the modes of action of NP at the cellular level.

Polyacrylic acid-coated and non-coated iron oxide nanoparticles induce cytokine activation in human blood cells through TAK1, p38 MAPK and JNK pro-inflammatory pathways

Iron oxide nanoparticles (ION) can have a wide scope of applications in biomedicine, namely in magnetic resonance imaging, tissue repair, drug delivery, hyperthermia, transfection, tissue soldering, and as antimicrobial agents. The safety of these nanoparticles, however, is not completely established, namely concerning their effect on immune system and inflammatory pathways. The aim of this study was to evaluate the in vitro effect of polyacrylic acid (PAA)-coated ION and non-coated ION on the production of six cytokines [interleukin 1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), interleukin 8 (IL-8), interferon gamma (IFN-γ) and interleukin 10 (IL-10)] by human peripheral blood cells, and to determine the inflammatory pathways involved in this production. The obtained results showed that PAA-coated and non-coated ION were able to induce all the tested cytokines and that activation of transforming growth factor beta (TGF-β)-activated kinase (TAK1), p38 mitogen-activated protein kinases (p38 MAPK) and c-Jun N-terminal kinases (JNK) were involved in this effect.

Mechanism of neutrophil activation and toxicity elicited by engineered nanomaterials

The effects of nanomaterials (NMs) on biological systems, especially their ability to stimulate inflammatory responses requires urgent investigation. We evaluated the response of the human differentiated HL60 neutrophil-like cell line to NMs. It was hypothesised that NM physico-chemical characteristics would influence cell responsiveness by altering intracellular Ca2+ concentration [Ca2+]i and reactive oxygen species production. Cells were exposed (1.95-125 μg/ml, 24 h) to silver (Ag), zinc oxide (ZnO), titanium dioxide (TiO2), multi-walled carbon nanotubes (MWCNTs) or ultrafine carbon black (ufCB) and cytotoxicity assessed (alamar blue assay). Relatively low (TiO2, MWCNTs, ufCB) or high (Ag, ZnO) cytotoxicity NMs were identified. Sub-lethal impacts of NMs on cell function were investigated for selected NMs only, namely TiO2, Ag and ufCB. Only Ag stimulated cell activation. Within minutes, Ag stimulated an increase in [Ca2+]i (in Fura-2 loaded cells), and a prominent inward ion current (assessed by electrophysiology). Within 2-4 h, Ag increased superoxide anion release and stimulated cytokine production (MCP-1, IL-8) that was diminished by Ca2+ inhibitors or trolox. Light microscopy demonstrated that cells had an activated phenotype. In conclusion NM toxicity was ranked; Ag>ufCB>TiO2, and the battery of tests used provided insight into the mechanism of action of NM toxicity to guide future testing strategies.

Polyacrylic acid coated and non-coated iron oxide nanoparticles are not genotoxic to human T lymphocytes

The use of iron oxide nanoparticles (ION) for diagnostic and therapeutic purposes requires a clear favorable risk-benefit ratio. This work was performed with the aim of studying the ability of polyacrylic acid (PAA)-coated and non-coated ION to induce genotoxicity in human T lymphocytes. For that purpose, their influence on cell cycle progression and on the induction of chromosome aberrations was evaluated. Blood samples collected from healthy human donors were exposed to PAA-coated and non-coated ION, at different concentrations, for 48h. The obtained results showed that, for all culture conditions, the tested ION are not genotoxic and do not influence the cell cycle arrest. Their possible cumulative effect with the iron-dependent genotoxic agent BLM was also evaluated. Blood samples collected from healthy human donors were exposed to ION, at different concentrations, for 48h, in the presence of a pre-determined toxic concentration of BLM. The obtained results showed that, for all culture conditions, the tested ION do not potentiate the clastogenic effects of BLM.

Ferroferric oxide nanoparticles induce prosurvival autophagy in human blood cells by modulating the Beclin 1/Bcl-2/VPS34 complex

Magnetic iron oxide nanoparticles (NPs) are emerging as novel materials with great potentials for various biomedical applications, but their biological activities are largely unknown. In the present study, we found that ferroferric oxide nanoparticles (Fe₃O₄ NPs) induced autophagy in blood cells. Both naked and modified Fe₃O₄ NPs induced LC3 lipidation and degraded p62, a monitor of autophagy flux. And this change could be abolished by autophagy inhibitors. Mechanistically, Fe₃O₄ NP-induced autophagy was accompanied by increased Beclin 1 and VPS34 and decreased Bcl-2, thus promoting the formation of the critical complex in autophagy initiation. Further studies demonstrated that Fe₃O₄ NPs attenuated cell death induced by anticancer drugs bortezomib and doxorubicin. Therefore, this study suggested that Fe₃O₄ NPs can induce prosurvival autophagy in blood cells by modulating the Beclin l/Bcl-2/VPS34 complex. This study suggests that caution should be taken when Fe₃O₄ NPs are used in blood cancer patients.