Immune Support Therapy- An Emerging Immunotherapy
Cancer immunotherapy has come at the right time as much of the twentieth century’s focus was on cancer immunosurveillance. For decades, cancer researchers have been interested in immunologic treatments against cancer but with little progress. The lack of effective treatment modalities for many inoperable solid malignancies led to the search of new therapeutic options such as adaptive immunotherapy. Immune Support Therapy, IST, is a promising immunotherapeutic approach for the treatment of cancer and is a modality for the treatment of cancer.
Discovery of Dendritic Cells
Ralph Steinman, who found a population of striking Dendritic-shaped cells in the spleen, first described Dendritic Cells, DCs. Shortly thereafter, it became clear that DCs existed in all lymphoid and most non-lymphoid tissues. Ralph M. Steinman has shared the Nobel Prize in Physiology and Medicine 2011 along with two other scientists “for his discovery of the DC and its role in adaptive immunity.”
The Function of Dendritic Cells
The functions of DC in the human body can be categorized as Antigen Presentation and activation of T cells, maintaining the immune tolerance and maintaining the immune memory in tandem with B cells. Thus, the mature DCs are exploited for its use in cancer immunotherapy.
What are Dendritic Cells?
DCs are immune cells that form part of the mammalian’s immune system. They are present in every person’s tissues, mainly the skin and the inner lining of the nose, lungs, stomach and intestines. Their function is to identify a foreign substance, including cancer cells, and process the bits of such foreign substances and thus, jumpstart the immune response by bringing the foreign substance to the attention of the rest of the immune system. Once activated, they migrate to the lymphoid tissues where they interact with T cells and B cells to initiate and shape the adaptive immune response. DCs are a highly specialized subtype of white blood cells with a unique function. Within the DC the cancer cells are destroyed and several pieces of the foreign material (antigens) are displayed on the cells’ surface of the DCs. The exhibition of antigens on the surface of the DC is recognized by other cellular effector cells that recognize and terminate tumor cells displaying similar materials as expressed by the DC.
What is Immune Support Therapy?
Immune Support Therapy, IST, is an autologous process that involves the harvesting of peripheral blood Mononuclear cells from the patient’s own blood by a process called Leukopheresis. The cells are then cultured in the specialized and sophisticated laboratory in the presence of immune stimulatory agents (cytokines) and matured into DCs by exposing them to the patient’s own inactivated tumor cells or with certain tumor specific proteins.
Matured DCs are infused through IV to the patient to boost and fortify the immune system of the patient. It provides a necessary stimulus that the body requires to fight back the cancer.
The heart of the DCs’ process is the presentation of the immature DCs with cancer specific tumor cells. Each cancer tumor has certain proteins that are phagocytosed peptides that are then presented on the surface of the DCs for the activation and proliferations of the T cells. The cells proliferate and secrete certain cytokines that act on the cancer cells. It is different from the conventional therapeutic modalities, since it is highly customized and tailor-made for individual patients and it amplifies the patient’s natural body defense mechanism.
At What Cancer Stage Should a Patient Consider IST?
The patient can consider DC therapy at any stage of the cancer
How Effective is IST?
Responses have generally been promising as it is an autologous process; it reduces cancer morbidity and improves the quality of life. Depending on the type of cancer and the functional status of patients, the response may differ from patient to patient.