Immunotherapy

Traditionally, different approaches have been used to treat cancers. Nowadays, immunotherapy is the forefront of cancer treatment. We are specifically interested in a type of immunotherapy that targets immune checkpoints.

Different types of cancer treatment

Concept of Immunotherapy

Immune checkpoint

The interaction of a co-inhibitory ligand on tumor cells (e.g. PD-L1) with its corresponding receptor on killer T cells (e.g. PD-1) results in an inhibitory Signal, resulting in T cell exhaustion. The immunotherapy uses antibodies against either the receptor or ligand to block this inhibitory signal, which reinvigorates killer T cells to attack/kill tumor cells.


Immune checkpoints are crucial regulatory mechanisms within the immune system that help maintain a balance between activating and inhibiting immune responses. These checkpoints play a crucial role in preventing excessive immune activation, which could lead to autoimmune diseases, while also preventing the evasion of immune surveillance by cancer cells. Key components of immune checkpoints include proteins on the surface of immune cells, particularly killer T cells (CD8+ T cells).

One of the well-studied immune checkpoint pathways is the programmed cell death protein 1 (PD-1) pathway. PD-1 is a cell surface receptor expressed on activated T cells, and its ligands, PD-L1 and PD-L2, are often found on the surface of certain cells, including cancer cells. When PD-1 binds to its ligands, it sends inhibitory signals that dampen the immune response, preventing the immune system from attacking normal cells.

Cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) is another important immune checkpoint. CTLA-4 is expressed on T cells and acts as a negative regulator of T cell activation. By binding to its ligands, B7-1 and B7-2, on antigen-presenting cells, CTLA-4 helps control the intensity of the immune response.

In addition to these two immune checkpoints, the Elahi lab has made significant contribution to the discovery/function of other immune checkpoints such as TIM-3, CD160, VISTA, and galectin-9.

Therapies targeting immune checkpoints have been developed to enhance the immune systems ability to recognize and destroy cancer cells. These therapies, known as immune checkpoint inhibitors, block the inhibitory signals, allowing T cells to mount a stronger immune response against cancer cells. Drugs like pembrolizumab, nivolumab, and ipilimumab have shown success in treating various types of cancers by unleashing the immune system to target and eliminate cancer cells.

Yes, immunotherapy has gained prominence in the field of cancer therapy due to its ability to harness the bodys immune system to recognize and destroy cancer cells. The immune system plays a crucial role in identifying and eliminating abnormal or cancerous cells, but cancer cells can sometimes evade detection. Immunotherapy works by enhancing or reprogramming the immune response to better target and attack cancer cells.

Here are some key reasons why immunotherapy is considered at the forefront of cancer therapy:

  • Immunotherapy can be highly specific, targeting cancer cells while sparing healthy cells. This targeted approach may lead to fewer side effects compared to traditional treatments like chemo-and-radiotherapy.

  • Some patients treated with immunotherapy experience durable and long-lasting responses. In some cases, the immune system & “remembers” how to recognize and attack cancer cells, providing ongoing protection against recurrence.

  • The immune system is dynamic and can adapt to changes in the cancer cells. This adaptability is crucial as cancer cells can mutate over time, potentially becoming resistant to other forms of treatment.

  • Immunotherapy has shown efficacy across various types of cancers. While certain types of immunotherapy may be more effective for specific cancers, the general principles of boosting the immune response can be applied to a wide range of malignancies.

  • Immunotherapy can be combined with other forms of treatment, such as chemotherapy or targeted therapies, to enhance overall effectiveness. Combinations of treatments can target different aspects of the cancer and improve the chances of success.

  • Over the years, there have been notable successes in immunotherapy, leading to improved outcomes for some patients with previously challenging- to-treat cancers. Drugs like immune checkpoint inhibitors have demonstrated significant clinical benefits in certain cases.

While immunotherapy has shown great promise, its important to note that not all patients respond equally, and the effectiveness can vary depending on the type of cancer and individual factors. Our ongoing research and clinical trials aim to refine and expand the use of immunotherapy in the treatment of various cancers.