Leukemia vaccine
Despite the fact that the possibility of treating leukemia with vaccination has been proven, the therapeutic effectiveness in the clinic still does not meet expectations. The study of new leukemia antigens and the creation of delivery systems using materials approved by the FDA are important and promising strategies for the development of vaccines for clinical use.
Researchers from the Institute of Technological Design (IPE) of the Chinese Academy of Sciences and the Hospital of Zhujiang Southern Medical University have developed a new type of targeted therapeutic vaccine against acute leukemia. It uses self-assembling microcapsules from polylactic acid to co-encapsulate the leukemia-associated epitope peptide (EPS8), highly expressed in leukemia patients, and an inhibitor of the immune checkpoint anti-protein-1 programmed cell death (anti-PD-1).
In the new study, clinical results showed high expression of EPS8 and programmed cell death peptides (PD-1, PD-L1) in leukemia patients, which can be used as a new type of leukemia antigen and a checkpoint for the vaccine, respectively. In the new vaccine, epitope peptides and antibodies to PD-1 can be easily, accurately and efficiently loaded into microcapsules from polylactic acid, which is facilitated by the unique ability of the microcapsule to self-assemble.
After a single vaccination, the slow destruction of the microcapsule shell at the site of local administration leads to the attraction of activated antigen-presenting cells and the gradual release of both loads. As a result, cytotoxic T-lymphocytes are activated.
The researchers also confirmed the availability of the new vaccine using different epitope peptides in different models. After single subcutaneous injections of vaccine preparations with various epitopic peptides, mice carrying leukemic xenografts obtained from humanized cell lines or from primary cells of patients showed better therapeutic results than mice receiving repeated injections of free antigen, antibody and commercial adjuvant. Prolonged release of tumor-associated peptide and anti-PD-1 may represent a strategy to enhance antitumor immune responses to leukemia.
The microcapsule-based formulation has demonstrated its excellent characteristics, showing the promise of a microcapsule-based vaccine for use against various leukemia antigens in the clinic. Due to the advantages of the FDA-approved polylactate-based material, the convenience of vaccine preparation, the variety of vaccine components and the excellent therapeutic effect, the microcapsule-based vaccine has great potential for clinical use.
Article X.Xie et al. Therapeutic vaccination against leukaemia via the sustained release of co-encapsulated anti-PD-1 and a leukaemia-associated antigen is published in the journal Nature Biomedical Engineering.
Aminat Adzhieva, portal "Eternal Youth" http://vechnayamolodost.ru based on the materials of the Chinese Academy of Sciences: Scientists Develop New Precise Therapeutic Leukemia Vaccine.