Lymphocytes against cancer

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Before proceeding to the description of methods of stimulation of lymphocytes cancer patients, it should focus on the question of why lymphocytes, in particular T-killers, under normal conditions, do not inhibit the growth of developing tumors. The answer to this question is not so obvious. Lymphocytes-helpers receive from antigen-recognition of macrophages information about tumor-associated proteins. If cells are the first line of the local defense (EC-cells and macrophages) not eliminated the cancer germ, in response involved distant lymph nodes and circulating lymphocytes, otherwise the entire body. This is verified by observations about frequent sensitization of circulating lymphocytes cancer patients to antigens of malignant tumors detected described in reaction suppression, adhesion of leukocytes. Moreover, some patients with a growing tumor blood lymphocytes in laboratory samples have a cytotoxic effect on tumor target cells, including cells remote from a patient's own tumor (this, however, does not mean that the same process takes place in the body). But it is obvious that all these immunological features missing that against tumors appeared as relentless reaction of rejection, which is observed during the transplantation of donor kidney or heart.
Explanations of such functional immunodeficiency few. First, it was already told that the cancer cells, obviously, produce immunosuppressive agents, "blinding" not all of immune cells, and those that are potentially dangerous to the tumor itself. The tumor razlive coordinated activity of the system, threatening its very existence. Secondly, antigens tumors are relatively weak, they occupy as if an intermediate position between private naimenovaniya proteins and ALLO-antigen someone else's body. Therefore, although recognized as "alien", but not mobilize fully army cytotoxic-killing cells. The maturation of T-suppressors occurs when the tumor growth so early that it suppresses the creation of a powerful cytotoxic immune system. Third, in the blood plasma of cancer patients are substances that block the interaction even the few available cytotoxic elements with target cells and physiological reproduction of T-killers. Washed from the plasma cells of the patient in vitro reactions manifest themselves more actively than in the presence of serum controls.
It is impossible not to admit that at this stage these arguments are quite speculative. Numerous studies that proved quantitative deficit of T-lymphocytes, proportional tumor stage, rather meet the expectations of the authors, than register the objective reality. An overall quantitative T-deficiencies in the early stages of tumor growth, patients were not recovered from the flu and a sore throat, and I would suffer from different infections. Total oppression protective reactions is observed only in the late stages of tumor process, as with any other protracted illness. The tumor is not destroys the immune system, and "cheating" him; it is "cut the tunnel" for the survival of their cell descendants, whose development is not as easy as on artificial nutrient media.
Therefore, today's notions of the "breakdown" of cytotoxic immune system at the very early stages of the emergence of cancer stem cells and in the course of their further development only talk about the inadequacy of our knowledge of the subtle mechanisms of formation and regulation of the killer features of lymphoid cells, Analysis of this issue became especially urgent after it was shown pronounced antitumor activity of circulating lymphocytes, artificially "educated" outside the body, and then returned to the bloodstream of the host.
In the study of cytotoxic action of lymphocytes under an electron microscope, it was established that the killing is preceded by the appearance on the membrane attacked cells numerous circle of holes. In the cytoplasm attacking killers celebrated the formation of granules containing newly formed proteins. Isolated from granules of the substance has the capacity to violate the integrity of the membranes of other cells. The emergence of membrane pores disrupts the normal exchange of fluid and electrolytes between the cell and the environment, and swelling of water leads to the death, the "explosion" of the cell.