The human immune system is a complex network of tissues and organs dispersed throughout the body. Immunology, as one of the most rapidly evolving fields in bio-medical research, has to date covered the essential cellular and molecular events neces-sary for immune responses to occur. However, it has paid relatively little attention to important developmental processes underlying the formation of the tissues themselves that carry out immune responses in humans and other mammalians. In contrast to the thymus and bone marrow that are the sole tissues for generating mature leukocytes for antigen...

The human immune system is a complex network of tissues and organs dispersed throughout the body. Immunology, as one of the most rapidly evolving fields in bio¬medical research, has to date covered the essential cellular and molecular events neces¬sary for immune responses to occur. However, it has paid relatively little attention to important developmental processes underlying the formation of the tissues themselves that carry out immune responses in humans and other mammalians. In contrast to the thymus and bone marrow that are the sole tissues for generating mature leukocytes for antigen...