Antigenicity tumors

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All variety of tumor proteins are now divided into two General groups: tumor-associated antigens and tumor-specific. The first may be common for normal and tumor cells at different stages of their development, the second characteristic only malignization cells.
For tumor antigens are two different methodological approaches; one is serological associated with the study of interaction of the sera of known specificity with tumour cells, the second - cytological, usually held in cell cultures. In recent years, are widely used monoclonal antibodies - pure reagents against a small group of specific molecules.
Some antigens found on normal cells, but is more often found in cells of tumors. Then talk about the greater expression (severity) of these antigens. This applies in particular to a number of embryonic-specific antigens. Another category of antigens from the number of tumor-associated associated with oncogenic viruses, genes which are included in the genome of animals. They also can be found in normal cells, supporting malignancy. Different tumor-associated and tumor-specific molecules are present on the surface of cells simultaneously or separately, but in any case, they are the markers of tumors. The location of these molecules on the cell surface forms an antigenic profile, which is typical not only for each type of tumor and tumor every individual.
Considerable period of time (since the mid 20-ies and 50-ies) went in science in the wrong direction finding cancer antigens, as the tumor was extracted from some of the organisms, and the answer to it antigens studied the other, genetically different. Getting inbred animals that eliminate differences in strong antigens tissue compatibility, allow to solve tasks. It immunogenetic study was the basis of strategic experiments in Oncology. Further advances were also obliged to breeding work, during which appeared korennye line of mice differing individual antigens, T - and B-deficient mice, the animals with genetically caused by sensitivity to spontaneous and transplantable tumors. In this sense, the history of searches cancer antigens is the newest history.
In 1963, G. I. Abelev with employees found in the serum of mice with hepatoma (tumor of the liver) is a special protein that is owned by its electrophoretic mobility to alpha globulins. Subsequently it was found in the serum of newborn mice, why and called alpha-fetoprotein (AFP from lat. petus - fetus). Soon another Soviet researcher, Yu. S. Tatarinov, showed the presence of AFP in the serum of patients with liver cancer. It was found that AFP most actively is synthesized by the liver of a fetus, the person on the 13-14-th week of pregnancy and up to 32 weeks, when it reaches the highest concentration. Its immunosuppressive action of lymphocytes in the mother and fetus, which may be due to physiological purpose AFP. Regardless research AFP noted the active participation of the liver in the suppression of immune reactions using soluble in blood products.
In addition, AFP hard formed regenerating liver cells of adult organisms. It reinforces the lack of intercellular contacts between hepatocytes, their separation; when the increase in the concentration of AFP growth of new hepatocytes is faster. The increase in the concentration of AFP is not characteristic hepatoma, it increased by tumors of testicular, lung, pancreas, and when non-tumorous liver diseases. However, the dynamic study AFP useful for prediction of diseases and, in combination with other indicators and has diagnostic value.