Periodic Reporting for period 2 - M-BLOOD (A Modular Approach to Multifunctional Red Blood Cell Mimics)
Berichtszeitraum: 2023-03-01 bis 2024-08-31
Each year, 5.6 million people around the world die from injuries, making uncontrolled bleeding a leading cause of preventable death. This is particularly impactful because nearly half of these injuries affect young people, creating significant social and financial burdens on the healthcare system.
Blood transfusions, using donor red blood cells (RBCs), are crucial for saving lives by restoring oxygen transport in patients who have lost a lot of blood. However, before transfusions can happen, necessary but time-consuming steps like matching donors to recipients due to the different blood groups must be completed, which can delay treatment in emergencies. Additionally, donor RBCs have a short shelf life, making it impossible to keep large stocks to use when sudden disasters occur (e.g. earthquakes, plane crashes, terrorist attacks etc.).
Thus, blood substitutes are highly sought after to overcome these limitations of donor blood. However, despite many efforts over the past few decades, no approved product for human use exists yet. Early attempts in the 1980s, driven by fears of HIV contamination in blood supplies, faced many failures. While most research has focused on creating simple oxygen carriers, real RBCs do much more, including transporting carbon dioxide, regulating nitric oxide, and acting as antioxidants—all essential and life-saving functions.
The goal of this ERC Consolidator project is to develop a synthetic RBC, called RBC MIMIC, which will replicate not only oxygen transport but the main biological functions of natural RBCs. Additionally, RBC MIMIC will be designed to perform extra tasks to address other health issues resulting from severe blood loss, aiming to create a superior blood substitute for early-stage resuscitation.
Blood transfusions, using donor red blood cells (RBCs), are crucial for saving lives by restoring oxygen transport in patients who have lost a lot of blood. However, before transfusions can happen, necessary but time-consuming steps like matching donors to recipients due to the different blood groups must be completed, which can delay treatment in emergencies. Additionally, donor RBCs have a short shelf life, making it impossible to keep large stocks to use when sudden disasters occur (e.g. earthquakes, plane crashes, terrorist attacks etc.).
Thus, blood substitutes are highly sought after to overcome these limitations of donor blood. However, despite many efforts over the past few decades, no approved product for human use exists yet. Early attempts in the 1980s, driven by fears of HIV contamination in blood supplies, faced many failures. While most research has focused on creating simple oxygen carriers, real RBCs do much more, including transporting carbon dioxide, regulating nitric oxide, and acting as antioxidants—all essential and life-saving functions.
The goal of this ERC Consolidator project is to develop a synthetic RBC, called RBC MIMIC, which will replicate not only oxygen transport but the main biological functions of natural RBCs. Additionally, RBC MIMIC will be designed to perform extra tasks to address other health issues resulting from severe blood loss, aiming to create a superior blood substitute for early-stage resuscitation.
The main component of RBC MIMIC is a particle loaded with hemoglobin (Hb), the protein that carries oxygen in our blood. These Hb-particles are equipped with various functional parts and special coatings to help them stay in the bloodstream longer.
In the first part of the project, the team worked on making these Hb-loaded particles. They started with hydrogel particles but found they could not hold enough Hb. So, they developed new types of nanoparticles (tiny particles) that could carry more Hb. To make sure these particles could stay in the bloodstream for a long time, the team explored different coatings. Initially, they tried using coatings that resembled the membranes of natural RBCs but ran into difficulties identifying key components. They then turned to PEGylation, a method that coats the particles with a molecule known as polyethylene glycol (PEG) to prevent them from being recognized and removed by the immune system. During this first part of the project, we tested these Hb particles extensively in lab settings and in living organisms. These tests showed that the particles were safe, worked well, and stayed in the bloodstream longer than free Hb.
In the second part of the project, the focus was on adding features similar to natural RBCs. Thus, we developed antioxidant nanoparticles using materials like cerium oxide, platinum, and gold to prevent Hb from turning into an inactive form. The team also tested antioxidant coatings and found they worked well to keep Hb functional.
We also managed to combine all these features to create complete RBC MIMIC. This was done by adding antioxidant coatings and PEG to the Hb particles, which helped them scavenge harmful molecules and stay functional.
Overall, the M-BLOOD project has made great strides in developing artificial RBCs that can carry a lot of Hb, stay stable, and last longer in the bloodstream. These advancements could greatly benefit medical treatments and diagnostics that rely on efficient oxygen carriers.
In the first part of the project, the team worked on making these Hb-loaded particles. They started with hydrogel particles but found they could not hold enough Hb. So, they developed new types of nanoparticles (tiny particles) that could carry more Hb. To make sure these particles could stay in the bloodstream for a long time, the team explored different coatings. Initially, they tried using coatings that resembled the membranes of natural RBCs but ran into difficulties identifying key components. They then turned to PEGylation, a method that coats the particles with a molecule known as polyethylene glycol (PEG) to prevent them from being recognized and removed by the immune system. During this first part of the project, we tested these Hb particles extensively in lab settings and in living organisms. These tests showed that the particles were safe, worked well, and stayed in the bloodstream longer than free Hb.
In the second part of the project, the focus was on adding features similar to natural RBCs. Thus, we developed antioxidant nanoparticles using materials like cerium oxide, platinum, and gold to prevent Hb from turning into an inactive form. The team also tested antioxidant coatings and found they worked well to keep Hb functional.
We also managed to combine all these features to create complete RBC MIMIC. This was done by adding antioxidant coatings and PEG to the Hb particles, which helped them scavenge harmful molecules and stay functional.
Overall, the M-BLOOD project has made great strides in developing artificial RBCs that can carry a lot of Hb, stay stable, and last longer in the bloodstream. These advancements could greatly benefit medical treatments and diagnostics that rely on efficient oxygen carriers.
During the remaining phase of the project, we plan to focus on developing additional subunits that perform essential functions of biological RBCs. These subunits will include capabilities such as carbon dioxide (CO2) removal and nitric oxide (NO) depletion, which are crucial for mimicking the natural behavior of RBCs. These functionalities will be integrated into the hemoglobin nanoparticles (Hb-NPs) to enhance their overall performance.
In parallel, we will also work on developing more advanced stealth coatings. Specifically, we will explore human serum albumin (HSA)-based coatings to further extend the circulation time of these artificial RBC mimics in the bloodstream. HSA is known for its biocompatibility and ability to evade the immune system, making it an ideal candidate for creating long-circulating RBC mimics.
Once these enhanced RBC mimics are developed, they will undergo rigorous testing. Initially, we will conduct comprehensive in vitro evaluations to assess their functionality, stability, and biocompatibility. Following successful in vitro tests, we will move to in vivo studies using murine models to evaluate their performance in a living organism. These studies will focus on understanding the circulation time, biodistribution, and overall efficacy of the RBC mimics in replicating the functions of natural RBCs.
By the end of the project, we aim to have a robust and multifunctional RBC mimic that can significantly improve therapeutic and diagnostic applications requiring efficient and long-lasting oxygen carriers.
In parallel, we will also work on developing more advanced stealth coatings. Specifically, we will explore human serum albumin (HSA)-based coatings to further extend the circulation time of these artificial RBC mimics in the bloodstream. HSA is known for its biocompatibility and ability to evade the immune system, making it an ideal candidate for creating long-circulating RBC mimics.
Once these enhanced RBC mimics are developed, they will undergo rigorous testing. Initially, we will conduct comprehensive in vitro evaluations to assess their functionality, stability, and biocompatibility. Following successful in vitro tests, we will move to in vivo studies using murine models to evaluate their performance in a living organism. These studies will focus on understanding the circulation time, biodistribution, and overall efficacy of the RBC mimics in replicating the functions of natural RBCs.
By the end of the project, we aim to have a robust and multifunctional RBC mimic that can significantly improve therapeutic and diagnostic applications requiring efficient and long-lasting oxygen carriers.