The magical effect of PD-1/PD-L1 inhibitors

In the "war" between the human body and cancer, the immune system is undoubtedly our most powerful weapon. In the immune system, T cells play an important role in the front line. They are like a well-trained army with live ammunition, always ready to identify and eliminate "enemies" such as cancer cells. However, cancer cells are also very cunning. They will use some special means to escape the attack of T cells, which involve PD-1 and PD-L1, which we will focus on today.

PD-1 stands for programmed death receptor, which is like a special "receiver" stationed on T cells. PD-L1 is programmed death ligand 1, a protein that can pair with PD-1, which is equivalent to a "telegram" that sends signals to PD-1. Under normal circumstances, the combination of PD-1 and PD-L1 can prevent the immune system from excessively attacking normal cells and maintain immune balance, but cancer cells will use this mechanism to seek "survival" for themselves. They express PD-L1 in large quantities, bind to PD-1 on T cells, and send a "truce" command to T cells, making T cells mistakenly believe that cancer cells are "their own people" and stop attacking, allowing cancer cells to evade the surveillance of the immune system and grow wantonly in the body.

Clinical significance of PD-1 and PD-L1

Based on the special mechanism of action of PD-1 and PD-L1, scientists have developed inhibitors targeting them, opening a new era of cancer immunotherapy, which has shown significant efficacy in the treatment of various cancers. For example, melanoma is a highly malignant skin cancer. Previous treatments have limited effect, but through the use of PD-1/PD-L1 inhibitors, many patients' conditions have been effectively controlled and their survival time has been significantly prolonged; and non-small cell lung cancer, as the most common type of lung cancer, PD-1/PD-L1 inhibitors combined with chemotherapy have become the first-line treatment options, bringing new hope to many patients.

Importance of detecting PD-L1 expression

The expression level of PD-L1 has important guiding significance in cancer immunotherapy. It can help doctors predict the patient's response to immunotherapy and thus develop a more personalized treatment plan. At present, the detection of PD-L1 expression level mainly adopts immunohistochemistry detection method, which determines the expression status of PD-L1 by staining tumor tissue sections and observing the number and proportion of stained cells.

The magical effect of PD-1/PD-L1 inhibitors

PD-1/PD-L1 inhibitors are like a magic key that can block the binding between PD-1 and PD-L1, relieve cancer cells from "hypnotizing" T cells, reactivate T cells, and restore their ability to recognize and kill cancer cells. Take sintilimab injection as an example, it is an anti-PD-1 monoclonal antibody drug independently developed in my country. It has achieved good results in the treatment of relapsed or refractory classical Hodgkin's lymphoma and other cancers, bringing more treatment options to domestic cancer patients.

Advantages and challenges of immunotherapy

Compared with traditional cancer treatments, immunotherapy has many advantages. Unlike chemotherapy drugs, it does not directly kill tumor cells, but works by mobilizing the body's own immune system, so the side effects are relatively small and the patient's quality of life can be better guaranteed. However, immunotherapy is not perfect and it also faces some challenges. For example, not all patients respond well to immunotherapy, and some patients may experience immune-related adverse reactions, such as rash, diarrhea, hepatitis, etc. This requires doctors to closely monitor the patient's physical condition during treatment and adjust the treatment plan in a timely manner.

In short, these two small proteins, PD-1 and PD-L1, have a huge influence on the occurrence and development of cancer and immunotherapy. With the continuous deepening of their research, I believe that more and more effective immunotherapy methods will be introduced in the future, bringing more hope and vitality to cancer patients, allowing us to achieve greater victory in this protracted battle against cancer.