Suppression of the immune response in cancer

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It is interesting to see, and another analogy. Pregnancy is always accompanied by a temporary atrophy of the thymus. Again, this is caused by the influence tireoidnykh hormones and aims physiologically to reduce the protection of the mother. After delivery thymus and its functional activity completely restored. In cancer of the thymus is also subject to involution. In the last stage of disease tissue of the thymus is almost devoid of lymphoid cells. This illustrates the complete depletion of the protective resources and progressive poisoning tumor of the thymus poisons. In one case, immunosuppression is transient, in another - irreversible.
Biochemist Century Potter wittily said: "Oncogenesis is blocked ontogenesis". The meaning of this statement is the recognition of not only the community, but also the differences in these States. When cancer in the body there is no natural switch, eliminating the unregulated growth of malignant cells and pathologically depressed immunity. Embryonic period has its genetically and hormonally specified time limit. Malignant tumor growth occurs on the background of the "fraud" of the organism immunological mimicry of the tumor, the increasingly deep paralysis of immunity. From many points of view tumor used a number of biological patterns associated with the greatest conquest of beings, capable of reproduction. Therefore it is so hard to find ways radical combat this insidious disease. And if a normal pregnancy is through the formation of special immunological relationship between a mother and a fetus, and help the body in the confrontation with the tumor should be carried out taking into account potential distortion on this side of physiology of the immune system.
For the analysis of immunosuppressive therapy in pregnancy and cancer it is also important to take into account the special mechanism that explains the dynamics of appearance of multiple antibodies in the body. Back in 1974, Danish immunologist Nils Ierne put forward the hypothesis that the immune system can maintain a sustainable balance only in the presence of self-restrictions. This scheme it is considered at the level of antibodies-globulins and antiglobulin. Millions of the antibodies produced have different amino acid specificity, especially in variable parts. Arising under the action of another antigen, each such parcel of antibodies is for the body "unprogrammed", new, and here - alien for resting B cells. These lymphocytes perceive unexpected variable part of the new antibodies as "antigen" and produce against him new antibody. This is already antibody second order, or anti-antibody.
The variable portion of the molecule of the first antibodies received the name of idiotype, and caused him antibody - antiidiotype. Experiments have shown that anti-antibodies in the body really formed. Thus there is a chain reaction, as each new antibody may encourage the appearance of antibodies against himself. Network idiotype-antiidiotype immune system reacts as if to herself.
It is clear that antiidiotype is always relative to the idiotype suppressor agent. Antiidiotype suppresses production of idiotype, as well as anti-antiidiotype inhibits the production of antiidiotype. "Dziadok for turnip, grandma for dedko, granddaughter for grandma..." and so on In the system consistently changing stimuli suppressor factors are updated constantly adjusting the response. So one might think that antibodies to tumor antigens do not damage growing cell tumors. If the original antigen (tumor) was not removed from the body, the first type of antibody then suppressed anti-antibodies (antiidiotype). Humoral immunity cannot be a long and continuous process.
You should tell because antiidiotype gave a completely new twist in the evaluation of antitumor immunity. Antibodies to tumor antigens are formed part B-cells, but these antibodies (idiotype) do not destroy cancer cells. Occurred to them later antiidiotype - products of other B-cells contain a section similar to the antigen, otherwise they would not be able to neutralize idiotype. Hence, antiidiotype can be used as a vaccine, which carries information about the active site (determinants) antigen. Immunologists say, "Antiidiotype bears "internal image" antigen", and think how to use this "image" to protect against the disease. Is it possible? While there is no single answer, but impressed that antiidiotype (as antigen) deprived suppressor ballast - the whole tumor cells, it can be produced in unlimited quantities by means of biotechnology.
We should not forget about the overwhelming effect of antiidiotype with respect to each earlier bioproduct, it is especially important for any kind of long-term treatment, or immunization.