From replacement terminology to physiological function
The paper argues that “blood substitute” is too broad a description for technologies designed to support a specific physiological function. Blood is a complex biological system. Oxygen transport and delivery are functions within that system that can be measured, characterized and investigated independently.
Within this framework, the authors define BHOC — Biological Hemoglobin Oxygen Carrier — as a biologically derived or biologically engineered hemoglobin-mediated oxygen-delivery material or therapeutic whose relevant molecular, oxygen-binding, pharmacological, vascular, redox and manufacturing properties can be quantitatively characterized and reproducibly controlled.
Precision Oxygen Therapeutics
The proposed framework moves the scientific question toward where, when, how much and how effectively oxygen is delivered. It emphasizes microvascular distribution, oxygen affinity and unloading, blood flow, diffusion, metabolic demand, vascular interactions and tissue-level oxygen availability.
- Blood is a system. Oxygen delivery is a function.
- BHOC is not proposed as a replacement for the established HBOC classification or the broader term oxygen carrier.
- The paper presents terminology and a testable research agenda for controlled microvascular and tissue-level oxygen delivery.