histology, lymphatic system

autoimmune disease

autoimmune disease

autoimmune disease

aka solid tissues

immunocompetent celss react and destroy microorganisms, foreign cells (transplanted and tumor), and virus infected cells

immune response using circulating Ab (Ig and glycoprot)

aka "bursa"

functional tissue

aka supportive tissue; FDC, mesenchyme, CT, fibroblasts, reticular cells

connective tissue framework

reticular cells, T and B lymphocytes, plasma cells, macrophages

dendritic cell in skin

bc of primary, secondary, and tertiary lysosomes eating stuff

• lamina propria
• solitary lymph NODULE
• aggregates of lymph nodules (aka Peyer's patches)

dense aggregates of lymphatic tissue forming a spherical mass

contains-reticular cells, reticular fibers, lymphocytes (T or B)

(not permanent structures); w/in LCT assoc w/ epithelium...aka cont w/ outside world (lamina propria of GI, urinary, respiratory); size and number increases during humoral responses and decrease when humoral response ends

• mantle
• germinal center

aka marginal zone or corona; outer, dense region of nodule containing small T and B lymphocytes

aka reactive center; lighter region in center of nodule w/ B cells undergoing prolif and differentiation; has light zone and dark zone

(in nodule) contains FDCs and centrocytes, mitotic figures (aka mult -cytes), apoptotic cells (cleaned up by macrophages)

(in nodule) contains DCs and centroblasts

has long, motile processes to give more SA and increase efficiency of Ag presentation

stem cells w/in mesenchyme or LCT

cleaved/folded nuc

LP of -ileum opp the attachment of mesentery

partially-encapsulated lymphatic organs; surrounded partially by CT capsule and partially by epithelium lining oral cavity

efferent vessels into deep cervical lymph nodes

• partially encapsulated
• ICT (trabeculae)
• infoldings of surface epithelium
• Waldeyer's ring
• participates in lymphopoiesis, Ab prod

lateral walls btw palatoglossal arch and palatopharyngeal arch

dense and nodular

hemi-capsule from which trabeculae partition the tonsil

stratified squamous epithelium which invaginates as mult crypts

drained by ducts bypassing tonsular crypts to empty directly onto surface

root of tongue posterior to row of vallate papillae

dense and nodular

stratified squamous epi which invaginates into a SINGLE crypt (partially keratinized)

hemi-capsule

drained by duct draining directly into single tonsillar crypt

posterior wall of nasopharynx

dense and nodular

pseudostratified columnar epithelium (aka respiratory) which makes mult FOLDS (NOT CRYPTS)

hemi-capsule

drained by ducts emptying into epithelial folds

lymph nodes and spleen

• kidney bean shaped
• COMPLETE CT capsule
• cortex
• medulla
• lymph sinuses
• afferent and efferent lymphatic vessels

channels for mvmt of lymph through node; NOT lined by continuous endothelium but are laced by recticular cells and fibers instead

• 1. subcapsular
• 2. peritrabecular
• 3. medullary

contains lymph nodules w/ germinal centeres

w/in cortex of lymph nodes; mostly T lymphocytes, HEV, T-cell diapedesis

in deep cortex of cortex of lymph nodes; are stimulated postcapillary venules; found in thymus gland, spleen, and areas of chronic inflammation

• no nodules
• looser lymphatic tissue
• medullary cords
• medullary sinuses

in lymph node; mostly B lymphocytes, plasma cells, and macrophages

• afferent-drain into subcapsular sinus
• efferent-exit lymph node through hilus

enter at hilus and travel through trabeculae to parenchyma

vasomotor only; innervate sm muscle of vascular channels

• lymphopoiesis
• Ab prod
• filtration of lymph (phagocytosis of particles by macrophages lying along sinuses)

fully encapsulated lymphoid organ; parenchyma is red and white pulp; efferent lymphatic vessels only

splenic artery>capsular arteries>trabecular arteries>central arterioles>penicilliary arterioles>sinusoids>postcapillary venules>trabecular veins>splenic veins

in spleen; lymphoid cells surrounding central arterioles; mostly T cells; reactive B cells form nodules w/ reactive centers; central arterioles become eccentrically placed

in spleen; barrel-shapped splenic sinusoids surrounded by macrophages, reticular cells, lymphocytes (cords of Billroth....lymphocytes)

vasomotor only; innervates sm muscle of vascular channels

filters blood (phagocytic cells of sinusoids and splenic cords), hematopoiesis, phagocytosis of RBCs, Ab prod, blood reservoir

completely encapsulated lymphoid; cortex and medulla in juvenile thymus, no lymphatic nodules, efferent lymphatic vessels only

APCs; endodermal (3rd pouch), interconnected via desmosomes, support and isolate (blood-thymus barrier), synth and secrete thymopoietin and other paracrine factors to reg thymocyte dev

aka desmosomes

aka thymulin, alpha and beta thymosin

in spleen; degenreating epithelial reticular cells, in adult

comprised of epithelial reticular cells w/in which is dense lymphatic tissue, no lymphatic nodules

thicker layer of epithelial reticular cells than thymic cortex, therefore reduced density of lymphatic tissue; contains Hassall's bodies

blood vascular supply distributed via septae to capillaries in parenchyma; HEVs represent sites of margination and diapedesis of immature T cells

vasomotor only; innervates sm muscle of vascular channels

• lymphopoiesis
• maturation of T lymphocytes
• thymus involutes in adults although we still have T cells...somehow

histiocytes, Kupffer cells, alveolar macrophages, DCs in lymph nodules, osteoclasts, pleural and peritoneal macrophages, microglia, Langerhans cells

in epidermis

serous cavities

bone surfaces

dust cells

liver sinusoids

LCT