What are CD169 macrophages?
CD169+ macrophages are reported to be the primary cell type infected during viral infection, and they can capture viral particles in the blood, absorb antigens, such as immune complexes and viruses, and then present them in a complete form to follicular B cells, inducing germinal centre B cellular responses (30,76,77).
Which area of spleen is rich in T cells?
CD4+ T cells, in particular T follicular helper (Tfh) cells, are found in the splenic TCZ/PALS and provide help to B cells in the follicle for the production of high-affinity antibodies through cytokine production (e.g., IL-21) and direct co-stimulation (e.g., ICOS-ICOS ligand) (63).
How do lymphocytes leave the spleen?
Exit of leukocytes from the spleen occurs mostly through the splenic veins in the red pulp, although some cells in the white pulp may exit the organ locally via a network of efferent lymphatic vessels (Pellas and Weiss, 1990).
Do T cells mature in spleen?
The thymus will have produced all the T cells an individual needs by puberty. After the T and B lymphocytes have matured in the thymus and bone marrow, they then travel to the lymph nodes and spleen where they remain until the immune system is activated. Lymph nodes are located throughout the body.
Does spleen produce B lymphocytes?
Abstract. The spleen is a key lymphoid organ for generating B-lymphocyte (B cell)-mediated humoral immunity. This review examines the key features and functions of splenic B cells. Splenic B cell subsets, including virgin, memory, and CD5+ B cells, are characterized by their phenotypic markers and functions.
How do lymphocytes enter the spleen?
While antigen can reach lymph nodes via afferent lymphatics, either taken up by dendritic cells or by drainage in lymph fluid, lymphocytes enter this organ via the specialized high endothelial venules (HEV).
What do lymphocytes do in the spleen?
The spleen also helps get rid of germs. It contains white blood cells called lymphocytes and macrophages. These cells work to attack and destroy germs and remove them from the blood that passes through the spleen.
What antibodies does the spleen produce?
The sheaths surround central arteries within the spleen and contain T lymphocytes that attack foreign bodies as the blood is filtered into the spleen. The lymphatic nodules are where B-lymphocytes predominate, producing antibodies to coat pathogens and flag them up for removal by scavenger cells.
Where do B and T cells originate from?
Both B and T lymphocytes originate in the bone marrow but only B lymphocytes mature there; T lymphocytes migrate to the thymus to undergo their maturation. Thus B lymphocytes are so-called because they are bone marrow derived, and T lymphocytes because they are thymus derived.