Erythrocyte membranes from slaughterhouse blood as potential drug vehicles: Isolation by gradual hypotonic hemolysis and biochemical and morphological characterization

A thermoresponsive chitosan-based in situ gel formulation incorporated with 5-FU loaded nanoerythrosomes for fibrosarcoma local chemotherapy

Local administration of drugs at tumor sites over an extended period of time shows potential as a promising approach for cancer treatment. In the present study, the temperature-induced phase transition of chitosan and poloxamer 407 is used to construct an injectable hydrogel encapsulating 5-FU-loaded nanoerythrosome (5-FU-NER-gel). The 5-FU-NERs were found to be spherical, measuring approximately 115 ± 20 nm in diameter and having a surface potential of -7.06 ± 0.4. The drug loading efficiency was approximately 40 %. In situ gel formation took place within 15 s when the gel was exposed to body temperature or subcutaneous injection. A sustained release profile was observed at pH 7.4 and 6.8, with a total 5-FU release of 76.57 ± 4.4 and 98.07 ± 6.31 in 24 h, respectively. MTT, Live/dead, and migration assays confirmed the cytocompatibility of the drug carrier and its effectiveness as a chemotherapeutic formulation. After in vivo antitumor assessment in a subcutaneous autograft model, it was demonstrated that tumor growth inhibition in 14 days was 90 %. Therefore, the obtained injectable chitosan-based hydrogel containing 5-FU-loaded nanoerythrosomes illustrated promising potential as a candidate for local and enhanced delivery of chemotherapeutics at the tumor site.

Berberine mediated fluorescent gold nanoclusters in biomimetic erythrocyte ghosts as a nanocarrier for enhanced photodynamic treatment

Photodynamic therapy (PDT) is a well-established cancer treatment method that employs light to generate reactive oxygen species (ROS) causing oxidative damage to cancer cells. Nevertheless, PDT encounters challenges due to its oxygen-dependent nature, which makes it less effective in hypoxic tumor environments. To address this issue, we have developed a novel nanocomposite known as AuNC@BBR@Ghost. This nanocomposite combines the advantageous features of erythrocyte ghost membranes, the photoresponsive properties of gold nanoclusters (AuNC) and the anticancer characteristics of Berberine (BBR) for cancer treatment. Our synthesized AuNC efficiently produce ROS, with a 25% increase in efficiency when exposed to near-infrared (NIR) irradiation. By harnessing the oxygen-carrying capacity of erythrocyte ghost cells, AuNC@BBR@Ghost demonstrates a significant improvement in ROS generation, achieving an 80% efficiency. Furthermore, the AuNC exhibit tunable emission wavelengths due to their excellent fluorescent properties. In normoxic conditions, treatment of A549 lung carcinoma cells with AuNC@BBR@Ghost followed by exposure to 808 nm NIR irradiation results in a notable increase in intracellular ROS levels, accelerating cell death. In hypoxic conditions, when A549 cells were treated with AuNC@BBR@Ghost, the erythrocyte ghost acted as an oxygen supplement due to the residual hemoglobin, alleviating hypoxia and enhancing the nanocomposite's sensitivity to PDT treatment. Thus, the AuNC@BBR@Ghost nanocomposite achieves an improved effect by combining the advantageous properties of its individual components, resulting in enhanced ROS generation and adaptability to hypoxic conditions. This innovative approach successfully overcomes PDT's limitations, making AuNC@BBR@Ghost a promising nanotheranostic agent with significant potential for advanced cancer therapy.

Interactions of ultrashort laser pulses with hemoglobin: Photophysical aspects and potential applications

Hemoglobin (Hb), a life-sustaining and highly abundant erythrocyte protein, is not readily fluorescent. A few studies have already reported Two-Photon Excited Fluorescence (TPEF) of Hb, however, the mechanisms through which Hb becomes fluorescent upon interaction with ultrashort laser pulses are not completely understood. Here, we characterized photophysically this interaction on Hb thin film and erythrocytes using fluorescence spectroscopy upon single-photon/two-photon absorption, and UV-VIS single-photon absorption spectroscopy. A gradual increase of the fluorescence intensity, ending up with saturation, is observed upon prolonged exposure of Hb thin layer and erythrocytes to ultrashort laser pulses at 730 nm. When compared to protoporphyrin IX (PpIX) and oxidized Hb by H₂O₂, TPEF spectra from a thin Hb film and erythrocytes showed good mutual agreement, broad peaking at 550 nm, supporting hemoglobin undergoes degradation and that same fluorescent specie(s) originating from the heme moiety are generated. The uniform square shaped patterns of the fluorescent photoproduct exhibited the same level of the fluorescence intensity even after 12 weeks from the formation, indicating high photoproduct stability. We finally demonstrated the full potential of the formed Hb photoproduct with TPEF scanning microscopy towards spatiotemporally controlled micropatterning in HTF and single human erythrocyte labelling and tracking in the whole blood.

Extracellular Hemoglobin: Modulation of Cellular Functions and Pathophysiological Effects

Hemoglobin is essential for maintaining cellular bioenergetic homeostasis through its ability to bind and transport oxygen to the tissues. Besides its ability to transport oxygen, hemoglobin within erythrocytes plays an important role in cellular signaling and modulation of the inflammatory response either directly by binding gas molecules (NO, CO, and CO2) or indirectly by acting as their source. Once hemoglobin reaches the extracellular environment, it acquires several secondary functions affecting surrounding cells and tissues. By modulating the cell functions, this macromolecule becomes involved in the etiology and pathophysiology of various diseases. The up-to-date results disclose the impact of extracellular hemoglobin on (i) redox status, (ii) inflammatory state of cells, (iii) proliferation and chemotaxis, (iv) mitochondrial dynamic, (v) chemoresistance and (vi) differentiation. This review pays special attention to applied biomedical research and the use of non-vertebrate and vertebrate extracellular hemoglobin as a promising candidate for hemoglobin-based oxygen carriers, as well as cell culture medium additive. Although recent experimental settings have some limitations, they provide additional insight into the modulatory activity of extracellular hemoglobin in various cellular microenvironments, such as stem or tumor cells niches.

Morphological Characteristics, Hemoglobin Content, and Membrane Mechanical Properties of Red Blood Cell Delivery Systems

Red blood cell (RBC)-based systems are under extensive development as platforms for the delivery of various biomedical agents. While the importance of the membrane biochemical characteristics in relation to circulation kinetics of RBC delivery systems has been recognized, the membrane mechanical properties of such carriers have not been extensively studied. Using optical methods in conjunction with image analysis and mechanical modeling, we have quantified the morphological and membrane mechanical characteristics of RBC-derived microparticles containing the near-infrared cargo indocyanine green (ICG). We find that these particles have a significantly lower surface area, volume, and deformability as compared to normal RBCs. The residual hemoglobin has a spatially distorted distribution in the particles. The membrane bending modulus of the particles is about twofold higher as compared to normal RBCs and exhibits greater resistance to flow. The induced increase in the viscous characteristics of the membrane is dominant over the elastic and entropic effects of ICG. Our results suggest that changes to the membrane mechanical properties are a result of impaired membrane-cytoskeleton attachment in these particles. We provide a mechanistic explanation to suggest that the compromised membrane-cytoskeleton attachment and altered membrane compositional and structural asymmetry induce curvature changes to the membrane, resulting in mechanical remodeling of the membrane. These findings highlight the importance of membrane mechanical properties as an important criterion in the design and engineering of future generations of RBC-based delivery systems to achieve prolonged circulation.

Modulation of Functional Characteristics of Mesenchymal Stromal Cells by Acellular Preparation of Porcine Hemoglobin

Exploring the potential usage of the acellular preparation of porcine hemoglobin (PHb) isolated from slaughterhouse blood as a cell culture media component, we have tested its effects on the functional characteristics of stromal cells of mesodermal origin. Human peripheral blood mesenchymal stromal cells (PB-MSCs) were used in this study as a primary cell model system, along with three mouse cell lines (ATDC5, MC3T3-E1, and 3T3-L1), which represent more uniform model systems. We investigated the effect of PHb at concentrations of 0.1, 1, and 10 μM on these cells’ proliferation, cycle, and clonogenic and migratory potential, and found that PHb’s effect depended on both the cell type and its concentration. At the lowest concentration used (0.1 μM), PHb showed the least evident impact on the cell growth and migration; hence, we analyzed its effect on mesenchymal cell multilineage differentiation capacity at this concentration. Even under conditions that induce a specific type of MSC differentiation (cultivation in particular differentiation media), PHb modulated chondrogenic, osteogenic, and adipogenic differentiation, making it a potential candidate for a supplement of MSC culture. Through a model of porcine hemoglobin, these findings also contribute to improving the knowledge of extracellular hemoglobin’s influence on MSCs >in vivo.

Improved pharmacokinetic and biodistribution of 5-fluorouracil loaded biomimetic nanoerythrocytes decorated nanocarriers for liver cancer treatment

Nanoerythrocytes membrane (NEs) has recently been used to improve pharmacokinetics and biodistribution for successful drug therapy. NEs intended to enhance the drug targeting due to immune evasion and long circulation. In this work, NEs could serve as efficient 5- fluorouracil (5-FU) carriers to target liver cells. NEs decorated 5-FU-loaded chitosan coated-poly (lactide-co-glycolic acid) nanoparticles (5-FU-C-NPs-NEs), chitosomes (5-FU-C-LPs-NEs) and 5-FU-NEs were prepared by hypotonic lysis and extrusion procedures. Moreover, 5-FU loaded-chitosan coated 5-FU-NPs (5-FU-C-NPs) and chitosomes (5-FU-C-LPs) for the compared issues were prepared. They were characterized in terms of particle size, encapsulation efficiency (EE), membrane protein content, phosphatidylserine exposure, surface morphology, and in vitro release profiles. Also, their cytotoxic efficacy was determined. Furthermore, pharmacokinetics and biodistribution studies were investigated for optimized formulation. The results revealed that 5-FU-C-NPs-NEs have narrow particle size distribution, desirable EE%, and retained the erythrocyte membrane properties as confirmed by polyacrylamide gel electrophoresis (SDS-PAGE). Additionally, it displayed a sustained release profile up to 72 h of 5-FU-C-NPs-NEs compared to other formulations. In comparison to 5-FU solution and 5-FU-C-NPs, 5-FU-C-NPs-NEs extended the drug release time in vivo with highly uptake by the liver. These results suggest that the 5-FU-C-NPs-NEs could be used to deliver 5-FU and enhance its targetability to liver cancer.

Native bovine hemoglobin reduces differentiation capacity of mesenchymal stromal cells in vitro

We have tested in vitro effects of hemoglobin from bovine slaughterhouse blood (BHb) on stromal cells of mesodermal origin, with an aim to explore its use as a component of cell culture media. Human peripheral blood mesenchymal stromal cells (PB-MSCs) and three mouse cell lines (ATDC5, MC3T3-E1 and 3T3-L1) were employed to study BHb effects on their growth and migration. The cells multilineage differentiation capacity in the presence of BHb was evaluated after induced differentiation, by histochemical staining and by RT-PCR analysis of the expression of genes specific for chondrogenic, adipogenic and osteogenic lineages. The effects of BHb on the cell proliferation and motility were dependent on both, cell type and BHb concentration (0.1 μM, 1 μM and 10 μM). In the lowest concentration (0.1 µM) BHb showed the least prominent effect on the cell proliferation and migration. In this concentration BHb reduced the differentiation capacity of all tested cells and its effect was dependent of composition of induction medium and the culture period. Obtained data suggest that BHb has the potential to be used as a component of cell culture media through maintaining proliferation and reducing differentiation capacity of mesenchymal stromal cells.

Adipoinductive effect of extracellular matrix involves cytoskeleton changes and SIRT1 activity in adipose tissue stem/stromal cells

Adipose tissue (AT) homeostasis and expansion are dependent on complex crosstalk between resident adipose stromal/stem cells (ASCs) and AT extracellular matrix (ECM). Although adipose tissue ECM (atECM) is one of the key players in the stem cell niche, data on bidirectional interaction of ASCs and atECM are still scarce. Here, we investigated how atECM guides ASCs' differentiation. atECM altered shape and cytoskeleton organization of ASCs without changing their proliferation, β-galactosidase activity and adhesion. Cytoskeleton modifications occurred due to fostered parallel organization of F-actin and elevated expression of Vimentin in ASCs. After seven-day cultivation, atECM impaired osteogenesis of ASCs, simultaneously decreasing expression of Runx2. In addition, atECM accelerated early adipogenesis concomitantly with altered Vimentin organization in ASCs, slightly increasing PPARγ, while elevated Adiponectin and Vimentin mRNA expression. Early adipogenesis triggered by atECM was followed by upregulated mitochondrial activity and Sirtuin 1 (SIRT1) expression in ASCs. Proadipogenic events induced by atECM were mediated by SIRT1, indicating the supportive role of atECM in adipogenesis-related metabolic state of ASCs. These results provide a closer look at the effects of atECM on ASC physiology and may support the advancement of engineering design in soft tissue reconstruction and fundamental research of AT.

Formulation and Drug Loading Features of Nano-Erythrocytes

Nano erythrocyte ghosts have recently been used as drug carriers of water-soluble APIs due to inherit biological characteristics of good compatibility, low toxicity, and small side-effect. In this study, we developed a novel drug delivery system based on nano erythrocyte ghosts (STS-Nano-RBCs) to transport Sodium Tanshinone IIA sulfonate (STS) for intravenous use in rat. STS-Nano-RBCs were prepared by hypotonic lysis and by extrusion methods, and its biological properties were investigated compared with STS injection. The results revealed that STS-Nano-RBCs have narrow particle size distribution, good drug loading efficiency, and good stability within 21 days. Compared with STS injection, STS-Nano-RBCs extended the drug release time in vitro and in vivo with better repairing effect on oxidative stress-impaired endothelial cells. These results suggest that the nano erythrocyte ghosts system could be used to deliver STS.

Characterization of carrier erythrocytes for biosensing applications

Erythrocyte abundance, mobility, and carrying capacity make them attractive as a platform for blood analyte sensing as well as for drug delivery. Sensor-loaded erythrocytes, dubbed erythrosensors, could be reinfused into the bloodstream, excited noninvasively through the skin, and used to provide measurement of analyte levels in the bloodstream. Several techniques to load erythrocytes, thus creating carrier erythrocytes, exist. However, their cellular characteristics remain largely unstudied. Changes in cellular characteristics lead to removal from the bloodstream. We hypothesize that erythrosensors need to maintain native erythrocytes’ (NEs) characteristics to serve as a long-term sensing platform. Here, we investigate two loading techniques and the properties of the resulting erythrosensors. For loading, hypotonic dilution requires a hypotonic solution while electroporation relies on electrical pulses to perforate the erythrocyte membrane. We analyze the resulting erythrosensor signal, size, morphology, and hemoglobin content. Although the resulting erythrosensors exhibit morphological changes, their size was comparable with NEs. The hypotonic dilution technique was found to load erythrosensors much more efficiently than electroporation, and the sensors were loaded throughout the volume of the erythrosensors. Finally, both techniques resulted in significant loss of hemoglobin. This study points to the need for continued development of loading techniques that better preserve NE characteristics.

Statins anticancer targeted delivery systems: re-purposing an old molecule

OBJECTIVES

Exploring the use of statins as anticancer agents and exploiting different drug delivery systems in targeting these molecules to cancerous sites. Literature review was performed to investigate the use of statins in cancer treatment in one hand, and the different pharmaceutical approaches to deliver and target these drugs to their site of action.

KEY FINDINGS

Statins were used for decades as antihypercholestrolemic drugs but recently have been proven potential for broad anticancer activities. The incorporation of statins in nanoparticulate drug delivery systems not only augmented the cytotoxicity of statins but also overcame the resistance of cancerous cells against the traditional chemotherapeutic agents. Statins-loaded nanoparticles could be easily tampered to target the cancerous cells and consequently minimal drug amount could be utilized.

SUMMARY

This review reconnoitered the different endeavors to incorporate statins in various nanoparticles and summarized the successful effects in targeting cancerous cells and reducing their proliferation without the side effects of commonly used chemotherapeutic agents.

Mapping of hemoglobin in erythrocytes and erythrocyte ghosts using two photon excitation fluorescence microscopy

The present study describes utilization of two photon excitation fluorescence (2PE) microscopy for visualization of the hemoglobin in human and porcine erythrocytes and their empty membranes (i.e., ghosts). High-quality, label- and fixation-free visualization of hemoglobin was achieved at excitation wavelength 730 nm by detecting visible autofluorescence. Localization in the suspension and spatial distribution (i.e., mapping) of residual hemoglobin in erythrocyte ghosts has been resolved by 2PE. Prior to the 2PE mapping, the presence of residual hemoglobin in the bulk suspension of erythrocyte ghosts was confirmed by cyanmethemoglobin assay. 2PE analysis revealed that the distribution of hemoglobin in intact erythrocytes follows the cells’ shape. Two types of erythrocytes, human and porcine, characterized with discocyte and echinocyte morphology, respectively, showed significant differences in hemoglobin distribution. The 2PE images have revealed that despite an extensive washing out procedure after gradual hypotonic hemolysis, a certain amount of hemoglobin localized on the intracellular side always remains bound to the membrane and cannot be eliminated. The obtained results open the possibility to use 2PE microscopy to examine hemoglobin distribution in erythrocytes and estimate the purity level of erythrocyte ghosts in biotechnological processes.

Development of nanosponges from erythrocyte ghosts for removal of streptolysin-O from mammalian blood

AIM

To produce mammalian biomimetic nanosponges from mammalian erythrocyte ghosts. Biomimetic nanosponges were studied in vitro as treatment platforms against exotoxin-related sepsis.

METHODS

Ovine blood was treated with hypotonic buffer to create erythrocyte ghosts and then subjected to sonication to produce erythrocyte vesicles of nonuniform size. Vesicles were then serially extruded through 400-nm and 100-nm polycarbonate membranes. Nanosponges were prepared by fusing poly(d,l-lactic-co-glycolic acid) cores with ovine erythrocyte vesicles.

RESULTS

Ovine erythrocytes were the most susceptible to streptolysin-O lysis, making it a model to study sepsis treatment. Ovine nanosponges adsorbed streptolysin-O at 37 and 40°C.

CONCLUSION

These results identify ovine nanosponges as novel therapeutic model to test adsorption of cholesterol binding toxins such as streptolysin-O.

Comparative studies on osmosis based encapsulation of sodium diclofenac in porcine and outdated human erythrocyte ghosts

The objective of our study was to develop controlled drug delivery system based on erythrocyte ghosts for amphiphilic compound sodium diclofenac considering the differences between erythrocytes derived from two readily available materials - porcine slaughterhouse and outdated transfusion human blood. Starting erythrocytes, empty erythrocyte ghosts and diclofenac loaded ghosts were compared in terms of the encapsulation efficiency, drug releasing profiles, size distribution, surface charge, conductivity, surface roughness and morphology. The encapsulation of sodium diclofenac was performed by an osmosis based process - gradual hemolysis. During this process sodium diclofenac exerted mild and delayed antihemolytic effect and increased potassium efflux in porcine but not in outdated human erythrocytes. FTIR spectra revealed lack of any membrane lipid disorder and chemical reaction with sodium diclofenac in encapsulated ghosts. Outdated human erythrocyte ghosts with detected nanoscale damages and reduced ability to shrink had encapsulation efficiency of only 8%. On the other hand, porcine erythrocyte ghosts had encapsulation efficiency of 37% and relatively slow drug release rate. More preserved structure and functional properties of porcine erythrocytes related to their superior encapsulation and release performances, define them as more appropriate for the usage in sodium diclofenac encapsulation process.

Biomembranes from slaughterhouse blood erythrocytes as prolonged release systems for dexamethasone sodium phosphate

The present study investigated preparation of bovine and porcine erythrocyte membranes from slaughterhouse blood as bio-derived materials for delivery of dexamethasone-sodium phosphate (DexP). The obtained biomembranes, i.e., ghosts were characterized in vitro in terms of morphological properties, loading parameters, and release behavior. For the last two, an UHPLC/-HESI-MS/MS based analytical procedure for absolute drug identification and quantification was developed. The results revealed that loading of DexP into both type of ghosts was directly proportional to the increase of drug concentration in the incubation medium, while incubation at 37°C had statistically significant effect on loaded amount of DexP (P < 0.05). The encapsulation efficiency was about fivefold higher in porcine compared to bovine ghosts. Insight into ghosts' surface morphology by field emission-scanning electron microscopy and atomic force microscopy confirmed that besides inevitable effects of osmosis, DexP inclusion itself had no observable additional effect on the morphology of the ghosts carriers. DexP release profiles were dependent on erythrocyte ghost type and amount of residual hemoglobin. However, sustained DexP release was achieved and shown over 3 days from porcine ghosts and 5 days from bovine erythrocyte ghosts. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1046-1055, 2016.

Physicochemical characterization of artificial nanoerythrosomes derived from erythrocyte ghost membranes

Colloidal stabile nanoerythrosomes with 200 nm average diameter were formed from hemoglobin-free erythrocyte ghost membrane via sonication and membrane extrusion. The incorporation of extra lipid (1,2-dipalmitoyl-sn-glycero-3-phosphocholine, DPPC), added to the sonicated ghosts, caused significant changes in the thermotropic character of the original membranes. As a result of the increased DPPC ratio the chain melting of the hydrated DPPC system and the characteristic small angle X-ray scattering (SAXS) of the lipid bilayers appeared. Significant morphological changes were followed by transmission electron microscopy combined with freeze fracture method (FF-TEM). After the ultrasonic treatment the large entities of erythrocyte ghosts transformed into nearly spherical nanoerythrosomes with diameters between 100 and 300 nm and at the same time a great number of 10-30 nm large membrane proteins or protein clusters were dispersed in the aqueous medium. The infrared spectroscopy (FT-IR) pointed out, that the sonication did not cause changes in the secondary structures of the membrane proteins under our preparation conditions. About fivefold of extra lipid--compared to the lipid content of the original membrane--caused homogeneous dispersion of nanoerythrosomes however the shape of the vesicles was not uniform. After the addition of about tenfold of DPPC, monoform and monodisperse nanoerythrosomes became typical. The outer surfaces of these roughly spherical objects were frequently polygonal, consisting of a net of pentagons and hexagons.

Pravastatin chitosan nanogels-loaded erythrocytes as a new delivery strategy for targeting liver cancer

Chitosan nanogels (CNG) are developed as one of the most promising carriers for cancer targeting. However, these carriers are rapidly eliminated from circulation by reticuloendothelial system (RES), which limits their application. Therefore, erythrocytes (ER) loaded CNG as multifunctional carrier may overcome the massive elimination of nanocarriers by RES. In this study, erythrocytes loaded pravastatin-chitosan nanogels (PR-CNG-ER) were utilized as a novel drug carrier to target liver cancer. Thus, PR-CNG formula was developed in nanosize, with good entrapment efficiency, drug loading and sustained release over 48 h. Then, PR-CNG loaded into ER were prepared by hypotonic preswelling technique. The resulting PR-CNG-ER showed 36.85% of entrapment efficiency, 66.82% of cell recovery and release consistent to that of hemoglobin over 48 h. Moreover, PR-CNG-ER exhibited negative zeta potential, increasing of hemolysis percent, marked phosphatidylserine exposure and stomatocytes shape compared to control unloaded erythrocytes. PR-CNG-ER reduced cells viability of HepG2 cells line by 28% compared to unloaded erythrocytes (UER). These results concluded that PR-CNG-ER are promising drug carriers to target liver cancer.