Fraunhofer Institute for Cell Therapy and Immunology IZIGMP Development
Development of an optimised cryopreservation process for the production of standardized leukapheresis products as the starting material for the development of novel immunotherapies
Immunotherapies based on T cells and natural killer cells (NK cells) are primarily produced from peripheral blood which is obtained from patients or donors through apheresis. To ensure that the apheresates can be provided in sufficient quantities for research and development, a standardized freezing process which should be as gentle as possible is required. In addition, the freezing process should also permit longer storage, as well as shipping of these starting products while assuring their quality. Therefore, this project aims to develop an optimized process for the separation and cryopreservation of leukapheresis products to permit fast and cost-effective access to this valuable starting material for the development of novel, cell-based medication.
To this end, fresh apheresates are prepared, divided into several batches and then cryopreserved using an optimized method at Fraunhofer IZI. The fresh apheresate and the defrosted products are then analyzed and compared in terms of their cellular parameters, such as cell count, vitality, composition and functionality, focusing on collecting comparative data regarding the phenotype and the fitness of the primary T and NK cells. In addition, the impact of cryopreservation on proliferative capacity and the cytotoxic activity of the immune cells relevant for treatment is examined.
Client
Haema AG
Inactivation of therapeutic immune cells by low-energy electron irradiation
This project aims to develop innovative irradiation processes for the production of modern cell and gene therapeutics.
Low-energy electron irradiation (LEEI) is an irradiation method suitable for the efficient inactivation of pathogens (such as viruses and bacteria) and eukaryotic cells. This inactivation method is based on the destruction of the genetic information (nucleic acids).
The new method has been patented, and Fraunhofer IZI has a research prototype which is unique worldwide, and which can be used to develop this irradiation technology and adapt it to various applications.
The project will evaluate low-energy electron irradiation for two specific application scenarios: The first application scenario will include the irradiation of leukocytes as an alternative method in extracorporeal photophoresis. Under the current method, the cells are treated using ultraviolet radiation with the addition of a photosensitiser (a light-activated substance). This treatment is, e.g., used in graft-versus-host disease, the main complication after allogenic haematopoietic cell transplants. If low-energy electron irradiation is used, the addition of a photosensitizer (which involves side effects) is not necessary.
The second application addresses the production of NK cell-based immune therapeutics. Unlike cell therapeutics from T effector cells (such as CAR T cells), natural killer cells have to be co-cultivated in a complex process using feeder cells to achieve the clinically required quantities of therapeutic cells. If feeder cells are used in GMP production processes, their growth is usually inhibited using irradiation methods for safety reasons. The suitability of LEEI as an alternative inactivation method for feeder cells will be examined as part of this project.
Combined cancer immunotherapy
A tumor cell is recognized and then destroyed by a CAR-positive NK Cell via the link using the ICE molecules.
The launch of CAR-T cell therapy to treat various cancers constitutes an important milestone for the use of cellular immunotherapy in oncology.
Apart from the high hopes that this promising treatment option will become available for various types of cancer as soon as possible, the increasing numbers of patients, in turn, are also connected with various challenges. One of these is that CAR-T cell products have to be tailored to the individual patient in a complex production process, resulting in limited availability and high treatment costs.
Therefore, international research efforts are focusing on alternative immunotherapies, in addition to optimized production processes.
Natural killer cells (NK cells) are considered a promising resource to optimize the cost-efficiency and availability of cancer immunotherapies. CAR-NK cells are genetically engineered according to the same principle as CAR-T cells to enable them to find and destroy tumor cells. Unlike T cells, NK cells are not immunogenic. This means, they can also be transferred from healthy donors to patients without triggering immunological rejection. As a result, NK and CAR-NK cell products can be produced more cost efficiently and on a larger scale.
Fraunhofer IZI has examined the potential of a combination treatment comprising NK cell products and so-called innate cell engagers (ICE) on behalf of Affimed GmbH (Mannheim).
These ICE molecules attach to both NK cells and tumor cells by binding to the CD16A receptor on the immune cells and a specific antigen (CD19) on the tumor cells. As soon as this bridge is created, the immune cell is activated and destroys the tumor cell.
In this project, the antitumor effectiveness of two combination treatments (NK cells and CAR-NK cells each combined with ICE) was examined in various in vitro experiments compared with the simple CAR-NK cell treatment. This showed that the cytotoxic potential of the combination treatment is superior to the simple version. Apart from this, a significant difference was not observed between the two combinations (NK cell + ICE vs. CAR-NK cell + ICE). The use of ICE in combination with an NK cell treatment has the potential for successful cancer immunotherapy. However, this potential now has to be examined in further pre-clinical and clinical studies.