Abstract
The immune system and ageing. The immune system is undergoing a lot of substantial changes during life which reflect different demands of every individual in different periods of life.
The most important ontogenetical dynamics is typical for specific cell-mediated immunity. The activity of Th2 subset of helper inducer CD4+ T cells is upregulated during early period of life.
There is the shift from Th2 subset reactivity to predominant Th1 subset reactivity during early adulthood. The return back to the predominant Th2 reactivity is typical for the late period of life.
The immune system of earderly people who are 90?100 years old is supprisingly well preserved. It is not possible to say now if this fact is either the cause or the consequence of successful senescence.
The term immunosenescence is now coined to describe the physiological changes of the immune system in elderly people.