HITV (human initiated therapeutic vaccine) therapy
The immune system removes foreign invaders from the body. HITV (human initiated therapeutic vaccine) therapy makes the best use of immune cells called dendritic cells, the commanders of the immune system.
The function of dendritic cells is to recognize (identify) foreign substances called antigens and present them to T lymphocytes. Specific CTLs (cytotoxic T lymphocytes), lymphocyte soldiers which possess antigen information identified by dendritic cells, are subsequently induced in the body and attack and kill cancer cells.
The key aspect in dendritic cell therapy is the way in which dendritic cells identify cancer cells as foreign. If dendritic cells can recognize specific cancer antigens, highly reactive CTLs against these antigens would be induced in the body.
Current dendritic cell therapies normally use surgically removed tissue or synthetic antigens called peptides, but live cancer cells in the patient's body carry the most specific cancer antigen.
Thus, HITV therapy aims to perform antigen recognition within the patient's body by directly injecting dendritic cells isolated from the patient into the tumor and ensuring that dendritic cells can identify the most specific cancer antigen, thereby inducing the most potent CTLs.
HITV therapy generally targets inoperable recurrent and stage 4 advanced cancers.
Advanced or recurrent cancer often presents as multiple lesions. This means that invisible micrometastatis has occurred throughout the body via the bloodstream as well as visible lesions detected by diagnostic imaging such as PET-CT. In such a case, a treatment plan has to be developed to systemically remove invisible micrometastases together with local control of visible lesions.
In HITV therapy, local control of the lesion is first performed in a combination treatment of radiation and intratumoral injection of dendritic cells. By injecting dendritic cells in the same area as irradiation, the cancer cells in the tumor are eliminated and CTLs (lymphocyte soldiers) are produced. We call this tumor vaccination. If this vaccination is done within the body, the tumor itself can become a manufacturing plant of CTLs (lymphocyte soldiers). Induced CTLs in the tumor constantly circulate through the whole body, thereby eliminating micrometastases at the same time.
A T cell is a type of lymphocyte which develops in the thymus gland and plays a central role in the immune response. T cells can be distinguished from other lymphocytes by the presence of a T-cell receptor on the cell surface. These immune cells originate as precursor cells, derived from bone marrow,[1] and develop into several distinct types of T cells once they have migrated in to the thymus gland - for which these cells are named. T cell differentiation continues even after they have left the thymus.
Groups of specific, differentiated T cells have an important role in controlling and shaping the immune response by providing a variety of immune-related functions. One of these functions is Immune-mediated cell death, and it is carried out by T cells in several ways: CD8+ T cells, also known as "Killer cells", are cytotoxic - this means that they are able to directly kill virus-infected cells as well as cancer cells. CD8+ T cells are also able to utilize small signalling proteins, known as cytokines, to recruit other cells when mounting an immune response. A different population of T cells, the CD4+ T cells, function as "Helper cells". Unlike CD8+ Killer T cells, these CD4+ Helper T cells function by indirectly killing cells identified as foreign: they determine if and how other parts of the immune system responds to a specific, perceived threat. Helper T cells also use cytokine signalling to influence regulatory B cells directly, and other cell populations indirectly. Regulatory T cells are yet another distinct population of these cells that provide the critical mechanism of tolerance, whereby immune cells are able to distinguish invading cells from "self" - thus preventing immune cells from inappropriately mounting a response against oneself (which would by definition be an "autoimmune" response). For this reason these regulatory T cells have also been called "Suppressor" T cells. These same self-tolerant cells are co-opted by cancer cells to prevent the recognition of, and an immune response against, tumour cells.
T細胞
專一性攻擊癌細胞,被樹突細胞所攜帶的抗原活化，可變身成CD8號 - T毒殺細胞，
來 直 接攻擊腫 瘤。亦可聯手B細胞，製造抗體，來攻擊腫瘤
樹突細胞
抗原活化使癌細胞呈現,讓的免疫細胞可專一性攻擊癌細胞