1.   Alternatively, the naive cells may be maturing rapidly into memory cells in response to the hypermutable, ever-elusive face of the virus that causes AIDS.

2.   Finally, even if the baboon cells matured, they would have to recognize human cells that are infected with microorganisms.

3.   The cells usually mature into bone, cartilage and fat cells.

4.   The next step is to create the foundation of cells and proteins on which these young cells can mature.

5.   The thymus, located in the upper chest, is the part of the immune system where T cells mature into disease fighters.

6.   In pregnancy, however, breast cells mature very quickly during the third trimester, and this makes them less sensitive to carcinogenic triggers.