White blood cells (WBCs), also called leukocytes or leucocytes, are the cells of the immune system that are involved in protecting the body against both infectious disease and foreign invaders. All white blood cells are produced and derived from multipotent cells in the bone marrow known as hematopoietic stem cells. Leukocytes are found throughout the body, including the blood and lymphatic system.

In the present book, fifteen typical literatures about advances in immune cells published on international authoritative journals were selected to introduce the worldwide newest progress, which contains reviews or original researches on immune cells, white blood cells and other blood cells etc. We hope this book can demonstrate advances in immune cells as well as give references to the researchers, students and other related people.