IMM250H1 Lecture 6: Lecture 6
Document Summary
Lymphocytes begin development during hematopoiesis (process of creating new blood cells in the body) Blood consists of 55% liquid (plasma; water), 45% cells (largely red blood cells also called erythrocytes; also contain wbc also called leukocytes) **much more red blood cells vs wbc"s. Hematopoietic stem cells (hscs) give rise to mature blood cells. Hematopoiesis occurs in the bone marrow (fatty substance in bone where wbc are produced) From birth onwards hematopoiesis occurs in the bone barrow (before birth inconsistent); exact location shifts over time and falls off with age. Hematopoiesis is an ongoing process natural death of innate leukocytes and na ve lymphocytes after days or weeks as means of constant supply of fresh, healthy leukocytes. Lymphocyte development requires progression from clp to mature ready to function: lymphocyte. At each step the cell becomes more and more specialized in structure and functional capacity. End of process cell with either mature b or t cell.
