Question

why immunity is decrease of man after old​

Answer 1

Explanation:

The increased number of memory cells that occupy tissue niches and the inflammatory milieu in turn may compromise the ability of naive B and T cells migrating from the bone marrow and thymus to lodge in the tissue. Together, these changes result in diminished immune function in the elderly.

Answer 2

Answer:

There are fewer white blood cells capable of responding to new antigens. Thus, when older people encounter a new antigen, the body is less able to remember and defend against it

Explanation:

The increased number of memory cells that occupy tissue niches and the inflammatory milieu in turn may compromise the ability of naive B and T cells migrating from the bone marrow and thymus to lodge in the tissue. Together, these changes result in diminished immune function in the elderly.