W5 Lymphatic System Flashcards
where is the spleen found
left upper abdomen
how is the spleen tissue identified as
dark red pulp with white nodule pulp
what are the 4 functions of the spleen
1) production of immunological responses for blood
2) removal of aged cells esp RBCs
3) recycling iron to bone marrow
4) ensures Haematopoiesis is normal in fetus
what spleen looks like on H + E
red pulp = small red dots
white pulp = purple spots
what is white pulp of the spleen
where lymphoid aggregate
what is red pulp of the spleen
bulk of splenic tissue
what do b cells form in white pulp
follicles at edge of central artery
what stain is used to view b cells forming a follicle
CD20
which artey supplies the spleen with blood
splenic artery
what are splenic central arteries surround by
PALs
what is found on the terminal ends of splenic artery branches
sheathed capillaries
what is blood filtered through before entering RP in spleen arteries
marcophages
what are the job of red pulp in spleen
sinuses that drain into splenic vein and remove old RBCs
what are sinuses of red plulp lined with
endothelial cells
what are the functions of the lymph nodes
- filtration of lumphatic fluid
- processing antigens
- begin immune response
- activation of b + T cells
- mature B cells to plasma cells
how is LN histologically described as
aggregates of lymphocyres organised in a closed off dense capsule
where does the vasulcar supply of LN enter
hilum
where do lymphocytes, APCs + antigens pass through to enter nodes
subcapsular sinus
where are the lymphoid follicles found
in the superficial cortex
how are sendocary follicles of LN identified
pale geminal centre for active immune response
what is the germinal centre (GC) made of
dividing B cells
what are centroblasts (CB)
mitotically active cells found in darker zone of GC
what are centrocytes (CC)
produce immunoblasts found in paler zone of GC
what is the CB closer to
medulla
what are CC closer to
capsule
what are paracortex
mainly T cells that transform into immunoblasts
what are immunoblasts
produce activated T cells
what is mucosa-associated lymphoid tissue (MALT)
lymphoid tissue around the body at muscosal surfaces
where are peyer patches found
lympoid follicles around ileum of small intestine
where is the thymus located in the body
anterioer mediastinum
what does the thymus do
development and proliferation of T cells
what does the structure of the thymus look like
made of lobdules occupied by T lymphocytes
what is the structure of each lobule
outer cortex
inner medulla
whats the main diff between infant and adult thymus
adult thymus has more adipose tissue between lobule
where do T cells enter thymus
the cortico-medullary junction
where do mature T cells between cloning
outer cortex
what are Hassall corpuscles in thymic medulla
groups of keratinised cells
what are white blood cells (WBC) known as
leucocytes
which cells are a part of the MPS
monocytes, macrophages
dendritic cells
what is Haematopoiesis
process of blood cell formation
where does Haematopoiesis occur in the body
bone marrow in axial skeleton
whats the role of the B cell receptor (BCR)
binds to antigen to activate B cell with T helper cell
what happens when a B cells is activated
undergo mitosis to mature into plasma cells and release antibodies
what do monocytes do
pahgocytic cells which ingest cell debris
which WBC is the largest
monocytes
how are monocytes identified under H+E
dented kidney bean shape nuclei
how are macrophages formed
from differentiated monocytes
what do dendritic cells do
process antigenic material and present on cell surface of T cell
what does the innate immune system do
provides rapid response to toxins
what immune system is MPS apart of
innate
what does the Innate immune response result in
inflammation
what does the adaptive immune system do
allows for lifelong immunity and memory of pathogens
what are the 2 types of lymphocyte attacks
humoural (b cells)
cellular (t cells)
what cells are responsible for innate immune responses
phagocytes and macrophages
whatis a kupffer cell
macrophages in the liver
what is a macrophage
cell which is a part of phagocytosis and APC
what is the common macrophage marker
CD68
what are tissue macrohages in CNS
microglia
whats the concern for brown alveolar macrophage
blood had entered to lungs
what do osteoblasts do in bones
influence Ca2+ in blood
what happens in the light zone
b cells interact with T cells
cell fate determination
