There are some antigenic determinants common to both smallpox and cowpox viruses. They may mature in either bone marrow or the thymus gland. All cells are initially produced in bone marrow. They are contained only within the lymphatic vessels and lymph nodes. All cells differentiate only form pluripotent stem cells.
Many cells populate organs, such as the spleen or the tonsils, after maturity.
I only 42. In a laboratory experiment, one group of people consumes an amount of pure water, a second group an equal volume of beer, and a third group an equal volume of concentrated salt solution that is hypertonic to their blood. Their urine production is monitored for several hours. There will be no significant difference. Plasma proteins in humans have many functions.