Understanding CAR T Cell Therapy For Cancer Immunotherapy

CAR Structure

CAR T cell therapy, which takes advantage of the unique abilities of T cells, may be beneficial in the treatment of cancer immunotherapy. It is possible that the use of CARs which are recombinant antigen receptors for cell-surface antigens, will have an effect on T lymphocyte selectivity and activity, for example. This therapy makes use of CAR T cells to generate tumor-targeted T cells in a short period of time, thereby reducing hurdles and expediting immunotherapy. T cells that have been genetically engineered to produce CARs function as “living pharmaceuticals” in both the short and long term, providing benefits in both the short and long term. T cells must be created first, before transduction and cell multiplication may take place in order to perform CAR engineering in T cells (1). For clonally developing and persistent T cells to express the CAR gene after transduction there must be some type of established gene transfer to occur after the transduction. CAR antibodies have the ability to target cell surface antigens, T lymphocytes, T lymphocyte progenitors, and other immune cells, such as natural killer cells (NK cells), among other things. CAR-tuned T cells are designed to perform a variety of functions in addition to just activating and departing. By combining CARs with high-potential and high-quality signals, it is feasible to modulate T cell proliferation, persistence, and effectiveness in the tumor microenvironment. Because CAR delivery has a broader variety of effects on T cells than TCR delivery, which is restricted by the affinity of TCRs for target antigen, CAR delivery has a stronger impact on T cell fate. This is due to the greater diversity of effects that CAR delivery has on T cells than TCR delivery (4). As intriguing as CARs are, they are confined to detecting only cell surface markers, which is a shame given the potential of the technology. Personalized cancer immunotherapy (PCI) is a rapidly emerging field that has tremendous potential due to its modularity and ability to be applied in a range of immunotherapies, including cancer immunotherapy.

Fig. 1 

An intracellular stimulating domain, which can improve CAR T-cell activation and function, as well as fragments of monoclonal antibodies that detect a specific protein on a cell membrane, are used in the construction of these antigen-identifier CARs (e.g., CD19 on B cells). Although new costimulatory intracellular domains have been identified within the surface of generation CAR T cells, it is not known whether these domains are responsible for the cells’ ability to grow and expand in the patient’s body following reinfusion (8). This intracellular domain, on the other hand, did not improve T cell cytotoxicity against the cancer cells that were the subject of the study.

Challenges in CAR-T Therapy

 Fig. 2

When employing CAR T cell treatment for solid tumors, it is challenging to discover antigens that are prevalent in the tumor but not in the surrounding healthy tissues. The growth of tumor cells from some ALL patients limits the use of CD19-targeted CAR-T cells in the treatment of B cell malignancies (9). After CAR T cell treatment for epithelial malignancies, it was discovered that antigen-null tumor cells constitute a possible resistance mechanism. To suppress an anti-tumor immune response, only tumor cells that lack all of the target molecules can concurrently target many antigens at once. It is possible to address the CAR’s antigen-binding component to numerous antigens via promiscuous receptors in the CAR. There are a number of CARs, such as NKG2D, that can specifically target the various ligands on the surfaces of tumor and immune suppressive cells. To bind ErbB homo- and heteromeric receptors, T1E, an ErbB promiscuous ligand, is used by other CARs (E2Rs). It’s also possible to link multiple SCVF files together this manner. CD19 deletions can be removed from xenograft mice by using bi-specific CAR T cells that target CD20 or CD123. Compared to mono-specific CAR T cells, bi-specific CAR T cells, such as Muc1 and PSCA in pancreatic malignancies, or Her2 and IL-13RA2 in glioblastoma, are superior in solid tumors (10). There is still hope for bi-specific CAR T cells, despite the fact that they haven’t been demonstrated to be superior to mono-specific CAR T cells in vivo yet. In bi-specific CARs, ZAP70 phosphorylation and downstream signaling was boosted when both target antigens were activated. This indicates the ability of tumor cells to activate bi-specific CAR T cells more effectively. In spite of the fact that B cell malignancies co-express CD19, CD20, and CD22, identifying other antigen pairings associated with malignancy but not seen in healthy tissues is a difficult task (5).

Epitope dissemination and activation of other tumor-associated antigens may aid in limiting the spread of malignancies that do not contain an antigen. When CAR T cells kill tumor cells, they can cross-present other tumor antigens to endogenous T cells, increasing the effectiveness of the anti-tumor response (11). T cells that can disseminate epitopes and even resist reactivation with tumors lacking an antigen may imply the development of immunological memory for new tumor-associated proteins, but this has not yet been shown in humans. Before this study, it was thought that CAR T cells that target mesohaline would accelerate epitope transmission in some people, however this was proved to be incorrect. Immune system activation and/or cross-presentation enhancement using CAR T cells can help spread epitope. According to a new study, in preclinical studies, IL-12-producing CAR T cells may be able to destroy tumor cells without an antigen. In conjunction with CD8a+ dendritic cells, T cells that express CD40L can directly boost tumor-specific T cells bystanders. More research is needed to see if CAR T cells can be tailored to better activate an endogenous anti-tumor response in order to better combat tumor heterogeneity (12).

Evaluation of Opportunities in CAR-T Therapy

The T lymphocytes are stopped from accessing the tumor by egressing from circulation and entering the tumor site after the tumor is identified. When malignancy is limited to a specific area, local rather than systemic administration of T cells may be more effective. Glioblastoma and human pleural malignancy can be effectively treated by CAR T cell injections into the brain and the pleural space (2).

A new treatment option approved by the FDA and the European Medicines Agency (EMA) for patients with recurrent acute lymphoblastic leukemia and other B cell malignancies has piqued the interest of medical professionals (13). Genetically engineered T cells (CAR-T cells), often known as “gene therapy medicinal commodities,” are at the forefront of medical technology (GTMPs). Many patients now have access to life-saving CAR-T cell therapies that are aimed precisely against CD19, which can help them survive.

Every year, around 40,000 people are treated with stem cell therapy (14). The sum of all of this is mind-boggling. Since it was first expanded to include a cell therapy module more than a decade ago, the EBMT registry has grown to include information on a wide range of cell therapy treatments. In late 2016, the European Medicines Agency (EMA) granted the European Biotechnology and Molecular Therapies (EBMT) permission to conduct a long-term study on the effects of CAR-T cell therapy on patients (3).

As a result of the registry, patients will be able to obtain CAR-T cells with greater ease in the future. Health authorities, insurance companies, patients, and pharmaceutical companies will all benefit from lower costs associated with the marketing authorization application process, as well as an increased likelihood of product withdrawals and diminished or non-existent efficacy as a result of increased adverse effects and decreasing efficacy for patients, health authorities, and pharmaceutical companies (15). Phase III trials with small patient groups could be replaced with real-world data gathered from patients who have been treated in a variety of ways, resulting in significant time and cost savings. Using this technology, researchers are actively investigating COVID-19 and colon cancer, both of which are unmet medical needs in the United States.

Table 1

Conclusion

Researchers faced both opportunities and challenges when using the EBMT registry to monitor the long-term efficacy and safety of commercial CAR-T cells in clinical trials. In the long run, we’ll have to deal with many responsibilities and expectations as a result of what we’ve just done. There will be a lot of wiggle room for the registry holder, EMA and healthcare professionals in this process.

List of abbreviations

Chimeric antigen receptor (CAR)

European Medicines Agency (EMA)

T-cell receptor (TCR)

European Biotechnology and Molecular Therapies (EBMT)

Blood and Marrow Transplantation (EBMT)

Natural Killer cells (NK cells)

Personalized Cancer Immunotherapy (PCI)

Physician Assistants (PAs)

Major Histocompatibility Complex (MHC)

Voluntary Harmonization Procedure (VHP)

Good manufacturing practice (GMP)

Advanced Therapy Medicinal Products (ATMP)

Genetically modified organisms (GMOs)

References

1. Patel, U., Abernathy, J., Savani, B.N., Oluwole, O., Sengsayadeth, S. and Dholaria, B., 2022. CAR T cell therapy in solid tumors: A review of current clinical trials. EJHaem, 3, pp.24-31.
2. Akbari, P., Katsarou, A., Daghighian, R., van Mil, L.W., Huijbers, E.J., Griffioen, A.W. and van Beijnum, J.R., 2022. Directing CAR T cells towards the tumor vasculature for the treatment of solid tumors. Biochimica et Biophysica Acta (BBA)-Reviews on Cancer, p.188701.
3. Sheykhhasan, M., Manoochehri, H. and Dama, P., 2022. Use of CAR T-cell for acute lymphoblastic leukemia (ALL) treatment: a review study. Cancer Gene Therapy, pp.1-17.
4. Xu, C., Ju, D. and Zhang, X., 2022. Chimeric antigen receptor T cell therapy: challenges and opportunities in lung cancer. Antibody Therapeutics.
5. Ramaiya, N.H. and Smith, D.A., 2022. Invited Commentary: Novel Cellular Immunotherapy (CAR T-Cell) in the Reading Room. RadioGraphics, 42(1), pp.E21-E22.
6. Li, X., Dai, H., Li, X., Li, P., Qian, W., Liang, A. and Han, W., 2022. Optimal model establishment of whole-process management data for CAR-T therapy in China—how should this be done?. Cellular & molecular immunology, 19(1), pp.122-124.
7. Kyte, J.A., 2022. Strategies for Improving the Efficacy of CAR T Cells in Solid Cancers. Cancers, 14(3), p.571.
8. Exley, M.A., Garcia, S., Zellander, A., Zilberberg, J. and Andrews, D.W., 2022. Challenges and Opportunities for Immunotherapeutic Intervention against Myeloid Immunosuppression in Glioblastoma. Journal of Clinical Medicine, 11(4), p.1069.
9. Date, V. and Nair, S., 2021. Emerging vistas in CAR T-cell therapy: Challenges and Opportunities in Solid Tumors. Expert Opinion on Biological Therapy, 21(2), pp.145-160.
10. Marofi, F., Motavalli, R., Safonov, V.A., Thangavelu, L., Yumashev, A.V., Alexander, M., Shomali, N., Chartrand, M.S., Pathak, Y., Jarahian, M. and Izadi, S., 2021. CAR T cells in solid tumors: challenges and opportunities. Stem cell research & therapy, 12(1), pp.1-16.
11. Akhoundi, M., Mohammadi, M., Sahraei, S.S., Sheykhhasan, M. and Fayazi, N., 2021. CAR T cell therapy as a promising approach in cancer immunotherapy: challenges and opportunities. Cellular Oncology, 44(3), pp.495-523.
12. Cortés-Hernández, A., Alvarez-Salazar, E.K. and Soldevila, G., 2021. Chimeric antigen receptor (CAR) T cell therapy for cancer. Challenges and opportunities: An overview. Cancer Cell Signaling, pp.219-244.
13. Patel, U., Abernathy, J., Savani, B.N., Oluwole, O., Sengsayadeth, S. and Dholaria, B., 2022. CAR T cell therapy in solid tumors: A review of current clinical trials. EJHaem, 3, pp.24-31.
14. Sheykhhasan, M., Manoochehri, H. and Dama, P., 2022. Use of CAR T-cell for acute lymphoblastic leukemia (ALL) treatment: a review study. Cancer Gene Therapy, pp.1-17.
15. Ravindranath, A., Dubey, A., Suresh, S., Chaudhuri, G. and Chirmule, N., 2021. CAR-T cell therapy in India requires a paradigm shift in training, education and health care processes. Cytotherapy, p.1384.

Order an Essay Now & Get These Features For Free:

Turnitin Report

Formatting

Title Page

Citation

Outline

Place an Order