Stealth RBC: Boutique RBC For the Discriminating Customer
Immunocamouflaged (Stealth) RBC: Alloimmunization to non-ABO Blood Group Antigens is a significant problem in transfusion medicine - especially in the chronically transfused patient. Our goals for the Stealth RBC:
• Compassionate Use in Alloimmunized Patients With ‘RARE’ Blood Types
• Prophylactic Use in At-Risk Individuals - Especially Chronically Transfused Individuals
• Meeting transfusion needs in Remote and/or Blood Supply Constrained Locations.
• Improved Supply of RhD‘who cares’ RBC (i.e., camouflaged RhD+) in low frequency countries (e.g., China). Predictive Mapping Studies suggests that PEGylated RhD+ RBC would be safe in both naive and alloimunized RhD- recipients.
Stealth RBC Research
Scanning EM of a polymer-modified RBC. Shows normal discoid morphology.
RhD+ red blood cells are effectively camouflaged from phagocytic recognition. Shown is the phagocytosis of unmodied and mPEG-modified RhD+ RBC opsonized with 8 human sourced anti-D alloantibodies using the clinically validated monocyte-monolayer assay (MMA). Note the effect of polymer size (2, 5 and 20 kDa) on the induction of immunocamouflage.