Nonvasoconstrictive hemoglobin particles as oxygen carriers
Yu Xiong1, Zhi Zhao Liu, Radostina Georgieva
1Institute of Transfusion Medicine and Berlin-Brandenburg Center for Regenerative Therapies, Charité-Universitätsmedizin Berlin , Charitéplatz 1, 10117 Berlin, Germany.
ACS Nano
|August 7, 2013
Summary
Novel hemoglobin particles (HbPs) around 700 nm offer a promising blood substitute. These HbPs demonstrate high oxygen affinity and low immunogenicity, avoiding side effects of earlier hemoglobin-based oxygen carriers (HBOCs).
Area of Science:
- Biomedical Engineering
- Hematology
- Materials Science
Background:
- Hemoglobin-based oxygen carriers (HBOCs) are investigated as universal blood substitutes.
- Previous HBOCs failed clinical trials due to side effects like vasoconstriction and NO scavenging.
- There is a need for HBOCs with specific size (100-1000 nm) and high oxygen affinity.
Purpose of the Study:
- To develop novel hemoglobin particles (HbPs) as a safer blood substitute.
- To create HbPs with high oxygen affinity and low immunogenicity.
- To overcome limitations of previous HBOCs.
Main Methods:
- Fabrication of unique hemoglobin particles (HbPs) approximately 700 nm in size using a novel technique.
- Characterization of particle size distribution, morphology, and hemoglobin content.
- In vitro perfusion of isolated mouse glomeruli with HbP suspensions.
Main Results:
- HbPs exhibited a narrow size distribution and uniform morphology.
- Hemoglobin content in HbPs was 80% of that in native erythrocytes.
- Perfusion studies showed normal, nonvasoconstrictive afferent arteriole behavior, indicating limited NO scavenging and no oxygen oversupply.
Conclusions:
- The novel HbPs are a highly promising blood substitute candidate.
- The developed fabrication technique is effective, simple, and yields particles with desirable characteristics.
- HbPs demonstrate potential to avoid critical side effects associated with earlier HBOCs.
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