Blood platelets can be stored for only up to a week, and hospitals often run short of this life-saving resource. To help overcome this problem, an EPFL startup called HemostOD has developed technology that can produce blood platelets in large volumes and on demand.
Many disorders such as leukemia, other types of cancers, certain congenital diseases, and conditions requiring heart surgery can lower the quality or quantity of patients’ blood platelets. Platelets play an essential role in blood clotting; when platelet counts are too low, hemorrhaging is a serious risk and a transfusion is often prescribed. Some 35,000-40,000 platelet transfusions are carried out in Switzerland every year, according to Swissmedic’s 2021 Haemovigilance report, but demand for platelets is surely higher since transfusion requests that can’t be met due to a lack of supply aren’t reflected in the official figures. What’s more, the shortage stands to get worse in the coming years owing to population growth, an increase in the number of elderly people, the rising incidence of blood cancer, and progress in the way blood cancer is treated. This shortage stands to pose a real challenge for hospitals, where turnaround times are tight: platelets are stored at room temperature. Given the possibility for bacterial contamination, they can be kept for only four to seven days. HemostOD’s system can go a long way towards helping hospitals address this problem by giving them the option of producing platelets on demand from adult stem cells.
Not only are platelets hard to come by at most hospitals, but many patients who need them have already received several transfusions in the past, meaning they’ve developed antibodies against donor platelet
Blood platelets are cell fragments produced from a type of bone marrow cell called megakaryocytes, which in turn are derived from larger stem cells called megakaryoblasts. Platelets are formed when megakaryocytes stretch out into blood vessels, forming ribbons, and then break into fragments under pressure from the blood flow. HemostOD’s device aims to replicate this process ex vivo so that platelets can be produced quickly and on a large scale in a laboratory. "In our system, a fluid containing megakaryocytes flows in a microfluidic device with tiny obstacles that provoke ribbon formation, causing the megakaryocytes to stretch out and subsequently break into platelets," says Élodie Dahan, who founded HemostOD along with fellow EPFL graduate Faouzi Khechana. They’ve spent the past two years developing their system at EPFL based on patents they acquired from a French university after seeing the potential for such technology. Dahan and Khechana have now finalized their system, which is ready to be implemented for a larger scale. Dahan still remembers that exciting moment when they generated their first bag of artificial platelets. "After several months of development work, we finally proved our system works!" she says.
HemostOD’s system uses blood or bone marrow stem cells that have been anonymized - i.e., treated to prevent the expression of antigen proteins on the surface, which would otherwise give the cells a "fingerprint." That means the platelets produced by the cells are universal: they can be administered to any patient regardless of their blood type or possible contraindications. Prof. Olaia Naveiras, from the Laboratory of Regenerative Hematopoiesis at the University of Lausanne, explains: "Not only are platelets hard to come by at most hospitals, but many patients who need them have already received several transfusions in the past, meaning they’ve developed antibodies against donor platelets. By using platelets derived from programmed cells without antigens, we can obtain a response that’s more like blood cells from a healthy person". Naveiras is collaborating with HemostOD on an Innosuisse project.
The platelet shortage is a global problem, and companies around the world are looking at ways to resolve it. Some of them, such as in Japan, have developed systems that could one day hit the market. "The solution we are developing has the advantage of not having to resort to multiple stem cell donations. We are able from a unique donation of cells to guarantee industrial production of constant quality in the long term" says Khechana. "That makes our system ideally suited to meet platelet demand worldwide."
Research to demonstrate large-scale feasibility
The next phase of HemostOD’s research will be carried out jointly with Lausanne University Hospital (CHUV), the University of Lausanne and the University of Geneva under a two-year project. The goal is to demonstrate that the system is capable of fabricating a high volume of blood platelets and then to test it in clinical trials. Khechana already has experience starting a business, as he founded an EPFL spinoff that was acquired by Intel in 2015. The prospects for HemostOD, his current venture, are also bright: the company completed a CHF 650,000 seed funding round in May 2021. "We’re actively seeking additional investors and hope to carry out our first human transfusion trials in 2025," says Khechana. "Our target is to launch the system in the market in 2027."