Microbiology and Immunology 3300B Lecture Notes - Lecture 5: Apoptosis, Splenic Vein, Haematopoiesis
9 Dec 2016
School
Department
Professor
Document Summary
Lymphoid tissues are where immune cells are born and develop (lymphopoiesis) and are also tissues where t and b cells start to rearrange dna to make a viable. They are also the sites for central tolerance critical in preventing autoreactive t and b cells. Bone marrow is the spongy tissue in the core of the long bones. B-cells rearrange their antibody genes and undergo central tolerance. T-cell produced here but not where they make receptor and central tolerance. Honey cone structure, which encompasses an outer rim (endosteal niche with osteoblasts, hemopoeitic stem cells, and reticular cells) and blood vessels within. Osteoblasts: generate bone and control hsc differentiation. Reticular cells: processes connect cells, form reticular network for support. B-cells go through a phase of development: early stage are in the endostele niche, as they develop into more mature b-cells they migrate towards the vascular niche to exit the bone marrow.
