Репозиторий Университета

To date, two chimeric antigen receptors (CAR)-T cell products from autologous T cells have been approved by The United States Food and Drug Administration (FDA). The case-by-case autologous T cell generation setting is largely considered as a pivotal restraining cause for its large-scale clinical use because of the costly and prolonged manufacturing procedure. Further, activated CAR-T cells mainly express immune checkpoint molecules, including CTLA4, PD1, LAG3, abrogating CAR-T anti-tumor activity. In addition, CAR-T cell therapy potently results in some toxicity, such as cytokine releases syndrome (CRS). Therefore, the development of the universal allogeneic T cells with higher anti-tumor effects is of paramount importance. Thus, genome-editing technologies, in particular, clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 are currently being used to establish “off-the-shelf” CAR-T cells with robust resistance to immune cell-suppressive molecules. In fact, that simultaneous ablation of PD-1, T cell receptor alpha constant (TRAC or TCR), and also β-2 microglobulin (B2M) by CRISPR-Cas9 technique can support the manufacture of universal CAR-T cells with robust resistance to PD-L1. Indeed, the ablation of β2M or TARC can severely hinder swift elimination of allogeneic T cells those express foreign HLA-I molecules, and thereby enables the generation of CAR-T cells from allogeneic healthy donors T cells with higher persistence in vivo. Herein, we will deliver a brief overview of the CAR-T cell application in the context of tumor immunotherapy. More importantly, we will discuss recent finding concerning the application of genome editing technologies for preparing universal CAR-T cells or cells that can effectively counter tumor escape, with a special focus on CRISPR-Cas9 technology.

To date, two chimeric antigen receptors (CAR)-T cell products from autologous T cells have been approved by The United States Food and Drug Administration (FDA). The case-by-case autologous T cell generation setting is largely considered as a pivotal restraining cause for its large-scale clinical use because of the costly and prolonged manufacturing procedure. Further, activated CAR-T cells mainly express immune checkpoint molecules, including CTLA4, PD1, LAG3, abrogating CAR-T anti-tumor activity. In addition, CAR-T cell therapy potently results in some toxicity, such as cytokine releases syndrome (CRS). Therefore, the development of the universal allogeneic T cells with higher anti-tumor effects is of paramount importance. Thus, genome-editing technologies, in particular, clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 are currently being used to establish “off-the-shelf” CAR-T cells with robust resistance to immune cell-suppressive molecules. In fact, that simultaneous ablation of PD-1, T cell receptor alpha constant (TRAC or TCR), and also β-2 microglobulin (B2M) by CRISPR-Cas9 technique can support the manufacture of universal CAR-T cells with robust resistance to PD-L1. Indeed, the ablation of β2M or TARC can severely hinder swift elimination of allogeneic T cells those express foreign HLA-I molecules, and thereby enables the generation of CAR-T cells from allogeneic healthy donors T cells with higher persistence in vivo. Herein, we will deliver a brief overview of the CAR-T cell application in the context of tumor immunotherapy. More importantly, we will discuss recent finding concerning the application of genome editing technologies for preparing universal CAR-T cells or cells that can effectively counter tumor escape, with a special focus on CRISPR-Cas9 technology.

To date, two chimeric antigen receptors (CAR)-T cell products from autologous T cells have been approved by The United States Food and Drug Administration (FDA). The case-by-case autologous T cell generation setting is largely considered as a pivotal restraining cause for its large-scale clinical use because of the costly and prolonged manufacturing procedure. Further, activated CAR-T cells mainly express immune checkpoint molecules, including CTLA4, PD1, LAG3, abrogating CAR-T anti-tumor activity. In addition, CAR-T cell therapy potently results in some toxicity, such as cytokine releases syndrome (CRS). Therefore, the development of the universal allogeneic T cells with higher anti-tumor effects is of paramount importance. Thus, genome-editing technologies, in particular, clustered regularly interspaced short palindromic repeat (CRISPR)-Cas9 are currently being used to establish “off-the-shelf” CAR-T cells with robust resistance to immune cell-suppressive molecules. In fact, that simultaneous ablation of PD-1, T cell receptor alpha constant (TRAC or TCR), and also β-2 microglobulin (B2M) by CRISPR-Cas9 technique can support the manufacture of universal CAR-T cells with robust resistance to PD-L1. Indeed, the ablation of β2M or TARC can severely hinder swift elimination of allogeneic T cells those express foreign HLA-I molecules, and thereby enables the generation of CAR-T cells from allogeneic healthy donors T cells with higher persistence in vivo. Herein, we will deliver a brief overview of the CAR-T cell application in the context of tumor immunotherapy. More importantly, we will discuss recent finding concerning the application of genome editing technologies for preparing universal CAR-T cells or cells that can effectively counter tumor escape, with a special focus on CRISPR-Cas9 technology.

© 2019, SPb RAACI. Inhibitory receptors CTLA-4 and PD-1 (immune checkpoints) play a key role in regulation of immune reactions. They suppress excessive immune response against pathogenic microbes and prevent autoimmune reactions. The immune checkpoints are targets of the modern effective therapy based on human and humanized monoclonal antibodies (ipilimumab and nivolumab, tremelimumab, pembrolizumab, etc). However, despite its high efficiency compared to standard chemotherapy, the therapy based on blocking immune check points is facing several problems, i.e., high therapy cost and severe negative autoimmune-related side effects. Unfortunately, this therapy helps to minority of the patients. Hence, further studies are required to improve its efficiency and safety, as well as to search for selection criteria of the patients who would benefit from the therapy. An appealing approach to reduce negative side effects from immune checkpoint inhibition is application of the blocking antibodies, aiming for ex vivo generation of patients’ activated immune cells for cancer therapy, thus avoiding systemic drug administration. Our aim was to elucidate influence of immune checkpoint blocking antibodies on the expression of CTLA-4 and PD-1 in such an in vitro model. First of all, we have determined quantities of lymphocyte receptors in peripheral blood of healthy volunteers, or cancer patients with disseminated melanoma. Moreover, we defined effect from the addition of antibodies against immune checkpoints on proportions of cells expressing CTLA-4 and PD-1 in the population of phytohemagglutinin-activated lymphocytes. Our study demonstrated that, in presence of antibodies to either of the two checkpoints during in vitro cell activation, the blockade of specific target receptor is accompanied by reduced number of cells positive for another checkpoint. Hence, the antibodies directed against PD-1 or CTLA-4 seem to suppress both negative signal cascades at once, if tested under such experimental conditions. Noteworthy, the response to blocking antibodies for different immune checkpoints varied for different donors. Our data may be used for development of effective combinations of lymphocyte activators and immune check-point inhibitors, for in vitro generation of activated lymphocytes applied for adoptive cancer therapy, as well as for prediction of possible responses to antibodies against CTLA-4 or PD-1, aiming to select the best personalized cancer immunotherapy.