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1.
Cancers (Basel) ; 15(24)2023 Dec 12.
Article in English | MEDLINE | ID: mdl-38136352

ABSTRACT

Artificial cells have been extensively used in many fields, such as nanomedicine, biotherapy, blood substitutes, drug delivery, enzyme/gene therapy, cancer therapy, and the COVID-19 vaccine. The unique properties of superparamagnetic Fe3O4 nanoparticles have contributed to increased interest in using superparamagnetic artificial cells (PLGA-Fe3O4 micro/nanocapsules) for targeted therapy. In this review, the preparation methods of Fe3O4 NPs and superparamagnetic artificial cell PLGA-drug-Fe3O4 micro/nanocapsules are discussed. This review also focuses on the recent progress of superparamagnetic PLGA-drug-Fe3O4 micro/nanocapsules as targeted therapeutics. We shall concentrate on the use of superparamagnetic artificial cells in the form of PLGA-drug-Fe3O4 nanocapsules for magnetic hyperthermia/photothermal therapy and cancer therapies, including lung breast cancer and glioblastoma.

3.
Front Bioeng Biotechnol ; 11: 1188399, 2023.
Article in English | MEDLINE | ID: mdl-37122869

ABSTRACT

This is a mini review on the biotechnological aspects of the most extensively developed hemoglobin-based oxygen carriers The emphasis is on the most recent Polyhemoglobin-catalase-superoxide dismutase-carbonic anhydrase (PolyHb-CAT-SOD-CA), which is a nanobiotechnological complex that is being investigated and scaled up with the potential for clinical use as nanobiotherapeutics. Hemoglobin, a tetramer, is an excellent oxygen carrier. However, in the body it is converted into toxic dimers. Diacid or glutaraldehyde can crosslink hemoglobin into polyhemoglobin (PolyHb) and prevent its breakdown into toxic dimers. This has been developed and tested in clinical trials. A bovine polyhemoglobin has been approved for routine clinical use for surgical procedures in South Africa and Russia. Clinical trials with human PolyHb in hemorrhagic shock were effective but with a very slight increase in non-fatal myocardial ischemia. This could be due to a number of reasons. For those conditions with ischemia-reperfusion, one would need an oxygen carrier with antioxidant properties. One approach to remedy this is with prepared polyhemoglobin-catalase-superoxide dismutase (PolyHb-CAT-SOD). Another reason is an increase in intracellular pCO2. We therefore added an enhanced level of carbonic anhydrase to prepare a PolyHb-CAT-SOD-CA. The result is an oxygen carrier with enhanced Carbonic Anhydrase for CO2 transport and enhanced Catalase and Superoxide Dismutase for antioxidant functions. Detailed efficacy and safety studies have led to the industrial scale up towards clinical trial. In the meantime, oxygen carriers are being investigated around the world for use in ex vivo biotechnological fluid for organ preservation for transplantation, with one already approved in France.

4.
Artif Cells Nanomed Biotechnol ; 50(1): 240-251, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36191131

ABSTRACT

This review concentrates on how artificial cells can contribute to helping patients with COVID-19. Artificial cells have led to mRNA vaccines with more improvements to come. Excessive cytokines in severe COVID-19 can damage organs leading to death. Artificial cell-based collodion macroporous activated charcoal adsorbent can effectively remove middle molecular weight range molecules in patients. A novel hemoperfusion device based on collodion membrane macroporous synthetic resin effectively removes cytokines and recovery in COVID-19 patients. This has been approved as an emergency treatment for COVID-19 in China, Europe, and Canada. A recent nanobiotherapeutic containing haemoglobin and up to six times the concentration of red blood cell enzymes: catalase, superoxide dismutase and carbonic anhydrase. In an animal study, this can effectively lower the damaging increase in free radicals and the removal of increased tissue pCO2. This can also help as blood substitute for the severe and critical problem of COVID-19 pandemic donor blood supply crisis.KEY MESSAGESCOVID-19 and its variants have resulted in major pandemics, severe sicknesses, and deaths around the world. COVID-19 and its variants has only started less than 3 years ago, and it is even more recently that we know more about its mechanisms, requirements, prevention, and treatment. This being the case, this is the first review on the present status and future perspectives of the use of the principle of artificial cells for COVID-19 related to vaccines, treatment, and critical donor blood supply shortage.


Subject(s)
Artificial Cells , Blood Substitutes , COVID-19 , Hemoperfusion , Animals , COVID-19/prevention & control , COVID-19/therapy , Carbonic Anhydrases , Catalase , Charcoal/therapeutic use , Collodion , Cytokines , Free Radicals , Hemoglobins , Humans , Resins, Synthetic , Superoxide Dismutase , Vaccines
5.
Cells ; 11(19)2022 10 05.
Article in English | MEDLINE | ID: mdl-36231094

ABSTRACT

BACKGROUND: The lack of a stable source of hepatocytes is one of major limitations in hepatocyte transplantation and clinical applications of a bioartificial liver. Human embryonic stem cells (hESCs) with a high degree of self-renewal and totipotency are a potentially limitless source of a variety of cell lineages, including hepatocytes. Many techniques have been developed for effective differentiation of hESCs into functional hepatocyte-like cells. However, the application of hESC-derived hepatocyte-like cells (hESC-Heps) in the clinic has been constrained by the low yield of fully differentiated cells, small-scale culture, difficulties in harvesting, and immunologic graft rejection. To resolve these shortcomings, we developed a novel 3D differentiation system involving alginate-microencapsulated spheres to improve current hepatic differentiation, providing ready-to-use hESC-Heps. METHODS: In this study, we used alginate microencapsulation technology to differentiate human embryonic stem cells into hepatocyte-like cells (hESC-Heps). Hepatic markers of hESC-Heps were examined by qPCR and Western blotting, and hepatic functions of hESC-Heps were evaluated by indocyanine-green uptake and release, and ammonia removal. RESULTS: The maturity and hepatic functions of the hESC-Heps derived from this 3D system were better than those derived from 2D culture. Hepatocyte-enriched genes, such as HNF4α, AFP, and ALB, were expressed at higher levels in 3D hESC-Heps than in 2D hESC-Heps. 3D hESC-Heps could metabolize indocyanine green and had better capacity to scavenge ammonia. In addition, the 3D sodium alginate hydrogel microspheres could block viral entry into the microspheres, and thus protect hESC-Heps in 3D microspheres from viral infection. CONCLUSION: We developed a novel 3D differentiation system for differentiating hESCs into hepatocyte-like cells by using alginate microcapsules.


Subject(s)
Human Embryonic Stem Cells , Alginates , Ammonia/metabolism , Capsules , Embryonic Stem Cells , Hepatocytes/metabolism , Humans , Hydrogels , Indocyanine Green/metabolism , alpha-Fetoproteins/metabolism
6.
Artif Cells Nanomed Biotechnol ; 49(1): 461-470, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34074185

ABSTRACT

Melanoma is a deadly skin cancer. Surgery is effective for early stages but there may be remnant cells. Treatments of later stages are associated with severe side effects. Moreover, a dangerous type of melanoma cannot be detected early enough for surgery. There is an urgent need for treatment with less severe side effects. We use a novel system of artificial cell polymer-lipid membrane nanocarrier containing a biomolecular nano-system of enzyme-oxygen biotherapeutic. In this report we show (1) its effectiveness and mechanisms in inhibiting the growth of melanoma in a 3D culture collagen medium that is more similar to that in the animal. (2) This allows us to design and carry out animal studies to successfully show that this can inhibit the growth of melanoma in an animal model. This includes following the tumour sizes and body weights every 2 days for 30 days followed by histology of the sites of injection and vital organs. We also analyze the action of the different components of the nanocarrier-nano-biotherapeutic complex. In conclusion, the results show the safety and clinical feasibility of this approach in the animal model and encourages further study towards clinical use.


Subject(s)
Membrane Lipids , Animals , Artificial Cells , Cell Line, Tumor , Mice , Oxygen
7.
Artif Cells Nanomed Biotechnol ; 47(1): 997-1013, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30945957

ABSTRACT

It is only in the last 20 years that many of the original ideas on artificial cells are being increasingly applied and extended by researchers around the world. Artificial cell has now evolved into nanomedicine, biotherapeutics, blood substitutes, drug delivery, enzyme/gene therapy, cancer therapy, cell/stem cell therapy, nanoparticles, liposomes, bioencapsulation, replicating synthetic cells, cell encapsulation/scaffold, biosorbent/immunosorbent haemoperfusion/plasmapheresis, regenerative medicine, encapsulated microbe, nanobiotechnology, nanotechnology and other areas. More futuristic research includes nanorobot, nanocomputer, multimodal locomotion delivery robot and others. This review starts with a general overview followed by specific examples in more details.


Subject(s)
Artificial Cells , Enzyme Therapy/methods , Hemoperfusion/methods , Nanomedicine/methods , Neoplasms/therapy , Plasmapheresis/methods , Regenerative Medicine/methods , Animals , Biotechnology , Blood Substitutes , Capsules , Humans , Immunosorbents , Liposomes , Microbiology , Nanoparticles , Neoplasms/genetics , Stem Cell Transplantation
8.
Artif Cells Nanomed Biotechnol ; 46(7): 1349-1363, 2018 Nov.
Article in English | MEDLINE | ID: mdl-29873524

ABSTRACT

The long-term safety and immunological effects of bovine poly-[haemoglobin-catalase-superoxide dismutase-carbonic anhydrase] in rats are studied by four-weekly 5% blood volume top-loading infusions followed by 30% blood volume exchange transfusion. There is no significant difference in growth, biochemistry and blood pressure between the control group receiving lactated ringer solution and those receiving the bovine poly-[haemoglobin-catalase-superoxide dismutase-carbonic anhydrase]. There is no significant change in mean arterial pressures (MAP) before and after each weekly top-loading infusion. After both the four weekly top-loading and the 30% exchange transfusions, the following safety and immune response evaluations are carried out. These include general studies on Ouchterlony double diffusion, total IgG and IgM, and complement activation. This is followed by quantitative measurements of specific antibodies against each of the following bovine components: Hb, CAT, SOD and CA in bovine poly-[haemoglobin-catalase-superoxide dismutase-carbonic anhydrase]. After the four weekly top-loading, each rat received a challenge of 30% blood volume exchange transfusion. The MAP, histamine and tryptase levels are tested before and after the 30% exchange transfusion. There are no anaphylactic reactions as shown by the MAP or histamine and tryptase. The results showed no safety problem nor adverse immune responses. All the rats survived when followed for one week after the 30% exchange transfusion.


Subject(s)
Blood Substitutes/adverse effects , Blood Substitutes/metabolism , Blood Transfusion , Blood Volume , Nanomedicine/methods , Protein Multimerization , Safety , Animals , Arterial Pressure/drug effects , Blood Substitutes/chemistry , Body Weight/drug effects , Carbonic Anhydrases/chemistry , Carbonic Anhydrases/metabolism , Catalase/chemistry , Catalase/metabolism , Cattle , Complement C3a/metabolism , Hemoglobins/chemistry , Hemoglobins/metabolism , Humans , Immunoglobulin G/blood , Immunoglobulin M/blood , Rats , Superoxide Dismutase/chemistry , Superoxide Dismutase/metabolism
11.
Artif Cells Nanomed Biotechnol ; 45(1): 46-50, 2017 Feb.
Article in English | MEDLINE | ID: mdl-27263665

ABSTRACT

We have prepared a novel nanobiotherapeutic, Poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase], which not only transports both oxygen and carbon dioxide but also a therapeutic antioxidant. Our previous study in a severe sustained 90 min hemorrhagic shock rat model shows that it has a hepatoprotective effect. We investigate its hepatoprotective effect further in this present report using an alcohol-damaged primary hepatocyte culture model. Results show that it significantly reduced ethanol-induced AST release, lipid peroxidation, and ROS production in rat primary hepatocytes culture. It also significantly enhanced the viability of ethanol-treated hepatocytes. Thus, the result shows that Poly-[hemoglobin-superoxide dismutase-catalase-carbonic anhydrase] also has some hepatoprotective effects against alcohol-induced injury in in vitro rat primary hepatocytes cell culture. This collaborate our previous observation of its hepatoprotective effect in a severe sustained 90-min hemorrhagic shock rat model.


Subject(s)
Carbonic Anhydrases , Catalase , Ethanol/toxicity , Hemoglobins , Hepatocytes/metabolism , Superoxide Dismutase , Animals , Carbonic Anhydrases/chemistry , Carbonic Anhydrases/pharmacology , Catalase/chemistry , Catalase/pharmacology , Cattle , Cells, Cultured , Hemoglobins/chemistry , Hemoglobins/pharmacology , Hepatocytes/pathology , Rats , Shock, Hemorrhagic/drug therapy , Shock, Hemorrhagic/metabolism , Shock, Hemorrhagic/pathology , Superoxide Dismutase/chemistry , Superoxide Dismutase/pharmacology
12.
Artif Cells Nanomed Biotechnol ; 43(3): 145-7, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26096663

ABSTRACT

Why is this important? Under normal circumstances, donor blood is the best replacement for blood. However, there are exceptions: During natural epidemics (e.g., HIV, Ebola, etc.) or man-made epidemics (terrorism, war, etc.), there is a risk of donor blood being contaminated, and donors being disqualified because they have contracted disease. Unlike red blood cells (RBCs), blood substitutes can be sterilized to remove infective agents. Heart attack and stroke are usually caused by obstruction of arterial blood vessels. Unlike RBCs, which are particulate, blood substitutes are in the form of a solution that can perfuse through obstructed vessels with greater ease to reach the heart and brain, as has been demonstrated in animal studies. Severe blood loss from injuries sustained during accidents, disasters, or war may require urgent blood transfusion that cannot wait for transportation to the hospital for blood group testing. Unlike RBCs, blood substitutes do not have specific blood groups, and can be administered on the spot. RBCs have to be stored under refrigeration for up to 42 days, and are thus difficult to transport and store in times of disaster and at the battlefront. Blood substitutes can be stored at room temperature for more than 1 year, compared to the RBC shelf life of 1 day, at room temperature. In cases of very severe hemorrhagic shock, there is usually a safety window of 60 min for blood replacement, beyond which there could be problems related to irreversible shock. Animal studies show that a particular type of blood substitute, with enhanced RBC enzymes, may be able to prolong the duration of the safety window.


Subject(s)
Blood Preservation/methods , Blood Substitutes/therapeutic use , Erythrocyte Transfusion/methods , Erythrocytes , Animals , Female , Humans , Male
13.
Artif Cells Nanomed Biotechnol ; 43(1): 1-9, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25297052

ABSTRACT

We crosslink hemoglobin (Hb), superoxide dismutase (SOD), catalase (CAT), and carbonic anhydrase (CA) to form a soluble polyHb-SOD-CAT-CA nanobiotechnological complex. The obtained product is a soluble complex with three enhanced red blood cell (RBC) functions and without blood group antigens. In the present study, 2/3 of blood volume was removed to result in 90-min hemorrhagic shock at mean arterial blood pressure (MAP) of 30 mmHg. This was followed by the reinfusion of different resuscitation fluids, then followed for another 60 min. PolyHb-SOD-CAT-CA maintained the MAP at 87.5 ± 5 mmHg as compared with 3 volumes of lactated Ringer's solution, 43.3 ± 2.8 mmHg; blood, 91.3 ± 3.6 mmHg; polyHb-SOD-CAT, 86.0 ± 4.6 mmHg; poly stroma-free hemolysate (polySFHb), 85.0 ± 2.5 mmHg; and polyHb, 82.6 ± 3.5 mmHg. PolyHb-SOD-CAT-CA was superior to the blood and other fluids based on the following criteria. PolyHb-SOD-CAT-CA reduced tissue pCO2 from 98 ± 4.5 mmHg to 68.6 ± 3 mmHg. This was significantly (p < 0.05) more effective than lactated Ringer's solution (98 ± 4.5 mmHg), polyHb (90.1 ± 4.0 mmHg), polyHb-SOD-CAT (90.9 ± 1.4 mmHg), blood (79.1 ± 4.7 mmHg), and polySFHb (77 ± 5 mmHg). PolyHb-SOD-CAT-CA reduced the elevated ST level to 21.7 ± 6.7% and is significantly (< 0.05) better than polyHb (57.7 ± 8.7%), blood (39.1 ± 1.5%), polySFHb (38.3% ± 2.1%), polyHb-SOD-CAT (27.8 ± 5.6%), and lactated Ringer's solution (106 ± 3.1%). The plasma cardiac troponin T (cTnT) level of polyHb-SOD-CAT-CA group was significantly (P < 0.05) lower than that of all the other groups. PolyHb-SOD-CAT-CA reduced plasma lactate level from 18 ± 2.3 mM/L to 6.9 ± 0.3 mM/L. It was significantly more effective (P < 0.05) than lactated Ringer's solution (12.4 ± 0.6 mM/L), polyHb (9.6 ± 0.7 mM/L), blood (8.1 ± 0.2 mM/L), polySFHb (8.4 ± 0.1 mM/L), and polyHb-SOD-CAT (7.6 ± 0.3 mM/L). PolyHb-SOD-CAT-CA can be stored for 320 days at room temperature. Lyophilized poly-Hb-SOD-CAT-CA can be heat pasteurized at 68F for 2 h. This can be important if there is a need to inactivate human immunodeficiency virus, Ebola virus, and other infectious organisms.


Subject(s)
Blood Substitutes/pharmacology , Carbonic Anhydrases/pharmacology , Catalase/pharmacology , Hemoglobins/pharmacology , Shock, Hemorrhagic/therapy , Superoxide Dismutase/pharmacology , Animals , Biological Transport , Blood Pressure/drug effects , Blood Substitutes/chemistry , Blood Volume , Carbon Dioxide/blood , Carbonic Anhydrases/chemistry , Catalase/chemistry , Cross-Linking Reagents/chemistry , Disease Models, Animal , Drug Stability , Fluid Therapy , Freeze Drying , Glutaral/chemistry , Hemoglobins/chemistry , Isotonic Solutions/administration & dosage , Lactic Acid/blood , Oxygen/blood , Rats , Rats, Sprague-Dawley , Resuscitation/methods , Ringer's Lactate , Shock, Hemorrhagic/blood , Shock, Hemorrhagic/physiopathology , Superoxide Dismutase/chemistry , Troponin T/blood
14.
Stem Cells Int ; 2012: 697094, 2012.
Article in English | MEDLINE | ID: mdl-23251190

ABSTRACT

Mesenchymal stem cells (MSCs) derived from bone marrow can secrete cytokines and growth factors and can transdifferentiate into liver cells. We transplanted polymeric membrane bioencapsulated MSCs into the spleens of 90% partial hepatectomized rats. This resulted in 91.6% recovery rates. This is compared to a recovery rate of 21.4% in the 90% hepatectomized rats and 25% in the 90% hepatectomized rats receiving intrasplenic transplantation of free MSCs. After 14 days, the remnant livers in the bioencapsulated MSCs group are not significantly different in weight when compared to the sham control group. From day 1 to day 3 after surgery, in the bioencapsulated MSCs group, the plasma HGF and IL-6 were significantly higher than those in the free MSCs group and control group (P < 0.01); plasma TNF-α was significantly lower (P < 0.001). We concluded that the intrasplenic transplantation of bioencapsulated MSCs significantly increases the recovery rates of 90% hepatectomized rats. It is likely that the initial effect is from proliver regeneration factors followed later by the transdifferentiated hepatocyte-like cells. However, histopathological analysis and hepatocyte proliferation study will be needed to better understand the regenerative mechanisms of this result. This study has implications in improving the survival and recovery of patients with very severe liver failure due to hepatitis, trauma, or extensive surgical resection.

15.
Article in English | MEDLINE | ID: mdl-21689051

ABSTRACT

Polyhemoglobin-superoxide dismutase-catalase-carbonic anhydrase (PolyHb-SOD-CAT-CA) is a therapeutic antioxidant that also transports both oxygen and carbon dioxide. This is formed by crosslinking Hb with SOD, CAT, and CA using glutaraldehyde. Crosslinking stroma-free Hb from red blood cell (RBC) reduces CA activity to 55%. Addition of more CA resulted in a preparation with the same CA activity as RBC. PolyHb in the complex acts as a buffer to prevent large pH changes as carbon dioxide is converted to carbonic acid. We then prepare and optimize a novel PolyHb-SOD-CAT-CA, a therapeutic antioxidant that also transports both oxygen and carbon dioxide.


Subject(s)
Blood Substitutes/metabolism , Carbon Dioxide/metabolism , Carbonic Anhydrases/metabolism , Catalase/metabolism , Hemoglobins/metabolism , Oxygen/metabolism , Superoxide Dismutase/metabolism , Animals , Antioxidants/metabolism , Biological Transport , Biotechnology , Buffers , Cattle , Cross-Linking Reagents/pharmacology , Glutaral/pharmacology , Hemoglobins/chemistry , Kinetics , Molecular Weight
16.
Article in English | MEDLINE | ID: mdl-22066797

ABSTRACT

Polymerized Porcine Hemoglobin (pPolyHb), a hemoglobin-based oxygen carrier (HBOC), was developed as a potential red blood substitute for clinical applications. Assessment of its effects on the immune system is an important component of the overall safety evaluation of HBOC. For this purpose, we assessed three inflammation indicators, including complement C3a, IL-6, and TNF-? in cultured cells and in a rat model when pPolyHb was incubated or administrated with the cells/animals. Our results suggested that the levels of these three indicators were not statistically changed upon pPolyHb stimulation, indicating that pPolyHb is not immunotoxic to cells and animals in this aspect.


Subject(s)
Blood Substitutes/adverse effects , Blood Substitutes/chemistry , Erythrocytes , Hemoglobins/adverse effects , Hemoglobins/chemistry , Immunity, Innate/drug effects , Swine , Animals , Biopolymers/immunology , Complement C3a/metabolism , Hemoglobins/immunology , Inflammation/chemically induced , Inflammation/immunology , Inflammation/metabolism , Interleukin-6/metabolism , Male , Protein Multimerization , Protein Structure, Quaternary , Rats , Rats, Sprague-Dawley , Shock, Hemorrhagic/chemically induced , Shock, Hemorrhagic/immunology , Shock, Hemorrhagic/metabolism , Swine/immunology , Tumor Necrosis Factor-alpha/metabolism
17.
Article in English | MEDLINE | ID: mdl-21574914

ABSTRACT

Polyhemoglobin-superoxide dismutase-catalase-carbonic anhydrase (PolyHb-SOD-CAT-CA) is a therapeutic antioxidant that also transports both oxygen and carbon dioxide. This is formed by crosslinking Hb with SOD, CAT, and CA using glutaraldehyde. Crosslinking stroma free Hb from red blood cell (rbc) reduces CA activity to 55%. Addition of more CA resulted in a preparation with the same CA activity as RBC. PolyHb in the complex acts as a buffer to prevent large pH changes as carbon dioxide is converted to carbonic acid. We then prepare and optimize a novel PolyHb-SOD-CAT-CA, a therapeutic antioxidant that also transports both oxygen and carbon dioxide.


Subject(s)
Antioxidants/metabolism , Blood Substitutes/metabolism , Carbonic Anhydrases/metabolism , Catalase/metabolism , Hemoglobins/metabolism , Multienzyme Complexes/metabolism , Reperfusion Injury/therapy , Superoxide Dismutase/metabolism , Animals , Antioxidants/chemistry , Antioxidants/therapeutic use , Biotechnology , Blood Substitutes/chemistry , Blood Substitutes/therapeutic use , Carbon Dioxide/metabolism , Carbonic Anhydrases/chemistry , Carbonic Anhydrases/therapeutic use , Catalase/chemistry , Catalase/therapeutic use , Cattle , Glutaral/metabolism , Hemoglobins/chemistry , Hemoglobins/therapeutic use , Humans , Multienzyme Complexes/chemistry , Multienzyme Complexes/therapeutic use , Nanotechnology , Oxidative Stress/drug effects , Oxygen/metabolism , Polymerization , Reperfusion Injury/metabolism , Superoxide Dismutase/chemistry , Superoxide Dismutase/therapeutic use
18.
Article in English | MEDLINE | ID: mdl-21381891

ABSTRACT

The objective of the present study is to evaluate the pharmacodynamic properties of polymerized porcine hemoglobin (pPolyHb) in an exchange transfusion model. Each of two groups of rats received a volume of pPolyHb or hetastarch that equalled 120-140% of estimated total blood volume (70 ml/kg) exchange transfusion. The results showed pPolyHb retained hemodynamic stability and exhibited superior volume expansion capability. Furthermore, pPolyHb effectively reverse anaerobic metabolism caused by a large amount of volume exchange. In comparison with hetastarch, pPolyHb increased blood oxygen content and tissue oxygenation. All these properties contribute to a higher effectiveness in sustaining the lives of rats in pPolyHb group.


Subject(s)
Exchange Transfusion, Whole Blood , Hemoglobins/pharmacokinetics , Oxygen Consumption , Oxygen , Polymerization , Anaerobiosis/drug effects , Animals , Glutaral/chemistry , Hemodynamics/drug effects , Hemoglobins/administration & dosage , Hemoglobins/chemistry , Hydroxyethyl Starch Derivatives/administration & dosage , Male , Models, Animal , Oxygen/blood , Oxygen Consumption/drug effects , Rats/immunology , Rats, Sprague-Dawley , Swine
19.
20.
Article in English | MEDLINE | ID: mdl-20564467

ABSTRACT

Unlike donor red blood cells (RBCs), blood substitutes can be treated to remove infective agents and can be used on the spot or in the ambulance in emergency without the time-consuming typing and cross-matching. Donor RBC requires storage at 4 degrees and is only good for 42 days, but blood substitutes can be stored for much longer time. For example, a bovine polyhemoglobin (PolyHb) can be stored at room temperature for more than 1 year. It has been shown as far back as 1957 that artificial RBC can be prepared with ultrathin polymer membranes of nanodimension thickness. To increase the circulation time, the first-generation engineered hemoglobin (Hb) is formed by using glutaraldehyde to crosslink Hb into soluble nanodimension PolyHb that has been tested clinically in patients. Further extension includes conjugated Hb, intramolecularly crosslinked Hb and recombinant Hb. For certain clinical uses, in addition to engineered Hb, we also need antioxidants to remove oxygen radicals to prevent injury from ischemia reperfusion. Thus, we use nanobiotechnology to prepare second-generation engineered Hb by assembling Hb together with superoxide dismutase (SOD) and catalase (CAT) to form a nanodimension soluble complex of polyhemoglobin (PolyHb)-CAT-SOD. A third generation system is to prepare nanodimension complete artificial RBCs that can circulate for sufficient length of time after infusion. One approach uses lipid vesicles to encapsulate hemoglobin (Hb). Another approach is to use biodegradable polymer-like polylactic acid or a copolymer of polyethylene glycol-polylactide (PEG-PLA) to form the membrane of nanodimension complete artificial RBC (www.artcell.mcgill.ca).


Subject(s)
Blood Substitutes , Hemoglobins , Nanotechnology/methods , Animals , Humans , Nanocapsules/chemistry
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