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[Внутри тимуса]

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Наша иммунная система борется
с инфекциями и раковыми клетками

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с помощью одного из видов лейкоцитов —

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Т-клеток, или T-лимфоцитов.

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Т-клетки вырабатываются органом,
который называется «тимус».

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== Далее пока что не переведено ==
Immature blood cells, made
from blood stem cells in the bone marrow,

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travel through the blood stream
to the thymus.

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Inside the thymus over the course
of approximately two weeks

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a network of different cells
impart chemical signals

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that affect the fate
of the immature T-cells.

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They are guided through
a process of development,

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selection,

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and also elimination,
to become mature T-cells.

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Firstly, the immature T-cells
are instructed to develop receptors.

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At the next stage,
those cells with receptors

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that can respond to the type of proteins
the ones useful to our immune system

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are signaled to survive,
the rest are eliminated.

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After this stage,
some of the developing T-cells

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may recognize proteins
from the healthy cells of our own body

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which can be dangerous
and cause auto-immunity,

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where they may target
those cells and tissues.

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In the final stage,
these cells are eliminated.

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The remaining now-matured T-cells,

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which have passed
through the selection process,

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enter the blood stream
and become part of our immune system.

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In fact, as little as 1% reach this stage

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and are now ready to protect
against harmful infection and disease,

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but not the healthy cells of our own body.

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From a young age, our thymus
degenerates -- getting smaller.

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Throughout our lives,
fewer and fewer T-cells are made,

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reducing our protection against
new infections and cancer,

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especially in old age.

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Finding ways to regenerate the thymus

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could help to boost the immune system
when this happens

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and could also lead to treatments
for a number of conditions

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affecting both the thymus
and the immune system.