a regularly used form of immune gene therapy. CAR-T involves manipulation of a patient's natural T cells to express a chimeric antigen receptor. This receptor, now on millions of the patient's T cells, recognizes cancerous cells that express specific antigens. Usually, the T cell antigen receptor is inactive but when the receptor recognizes a certain cancerous antigen, the physical structure of the T cell changes to destroy the cancer cell. This is a method of cancer treatment that works on the cellular and molecular level. Combining CAR-T with Checkpoint Inhibitors, Cytokines Some regulatory proteins, specifically immune checkpoint inhibitors, have been found to reduce the ability of T cells to multiply within the body. In order to optimize the efficacy of CAR-T gene therapy, these checkpoint inhibitors can be blocked to stimulate a robust anti-tumor immune response, spearheaded by the CAR-T cells. There are various known inhibitory receptors on the CAR-T cell; through manipulation of these receptors and the molecules that bind them, expression of the CAR-T cell can be amplified. CAR-T cells can also be combined with cytokines to improve the efficacy of the immunotherapy method. Cytokines are messenger molecules that can act on themselves, nearby cells, or distant cells. The signal pathways of these cytokines can be used to enhance CAR-T anti-tumor characteristics. For example, Interleukin 2 (IL2) is a cytokine that acts as a growth factor for various immune system cells, including T cells. In regards to gene therapy, IL2 can be used to increase replication and dispersing of CAR-T cells throughout the body. Issues with CAR-T Therapy There is room for improvement with this gene therapy approach. Firstly, the antigens of interest expressed on the cancer cells may sometimes be expressed on regular body cells, too. This means the body's T cells will attack its own healthy cells instead of the cancer cells when the antigen is lacking specificity with just the cancer cell. A possible solution to this problem is to include two different antigen receptors on the CAR-T cells to make them even more specific. The second issue with the CAR-T immunotherapy approach is that it can cause cytokine release syndrome. This is when an excess of pro-inflammatory factors are released by the immune system and can cause unpleasant side effects for the patient like nausea and a high fever. Gene Therapy In the past few decades, gene therapy has emerged as a targeted way