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Updated: Aug 13, 2026

Examination of Thymic Positive and Negative Selection by Flow Cytometry
Published on: October 8, 2012
Pathogenetic Principle of Immune System Evaluation in Human: Positive and Negative Activation
Anatoly N. Cheredeev1, Leonid V. Kovalchuk
1Russian State Medical University, Moscow, Russia.
Abstract:
The main advantage of the pathogenetic principle for immune system evaluation is that the principle allows to optimize assessment of the main and accessory functions of immunocompetent cells. The investigation of immune system begins from the evaluation of cell recognition function, and then, step by step, the investigator moves further, while determining the capacity of immunocompetent cells to be activated, to proliferate and differentiate. The investigation of immune system may be terminated at its every stage once a defect in immune system is detected. Activation is one of the most important stage of cell life. Cell activation may be positive (complete functional cell cycle) or negative (apoptosis). It is suggested to pay attention to identification of defects in both positive, and negative chains of activation, since enhanced negative activation may be associated with different types of immunodeficiencies, whereas the absence of apoptosis (high positive activation) likely may be a cause of autoimmune and lymphoproliferative disorders.
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