Innate Immunity

nonspecific (innate) immunity
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Terms in this set (90)
nonspecific (innate) immunity
provides a first line of defense against infection by nonspecifically blocking entry of microbes and targeting them for destruction or removal from the body.
Built in defenses
Immunity
Ability to fight infections or toxins
Susceptibility
Lack of resistance to adisease
Innate ( nonspecific)
Physical
Mechanical
Microbiome
Cellular defense
Lymphatic system
Phagocytosis
Inflammation
Fever
innate immunity
Present at birth
Protect against pathogens
Don't discriminate between non/self
No memory
lymphatic system
Composed of a network of vessels, ducts, nodes, and organs. Provides defense against infection.
Lymphatic system does what?
Carries micrones to lymph nodes where lymphocytes and macrophages destroy the pathogen
lymphatic system functions
Collects fluid from the inter- cellular spaces
Transport digested fats to the circulatory system
Provide innote & adaptive defenses
lymph
Fluids from tissue
Care white blood cells
Primary lymphoid tissues
bone marrow and thymus
lymph system: bone marrowContains hematopoietic stem cells Differentiate and mature into different blood cells and lymphocytesThymusAn immune organ located near the heart. THe thymus is the site of T cell maturation and is larger in children and adolescents.Secondary lymphoid tissuesspleen Lymph Diffused lymphoid tissuesspleen functionfilters blood Captures pathogens and antigens Contains macrophages crucial for antigen presentation: important fo t-cell activationlymph node functionRich in B and t lymphocytes Contains macrophages and dendritic calls for antigen presentationInfection of lymphatic systemlymphangitis Triggers inflammation responseBuboswollen lymph nodephysical defenses includephysical barriers, mechanical defenses, microbiomephysical barriers at cellular level areBarriers consist of cells tightly joined togetherPhysical: Skinbarrier composed of3 layers of closely packed cells Most important Shedding and drones inhibits microbial growth3 layers of skin areepidermis, dermis, hypodermisEpidermisOuter layer of skin Packed with keratin: protective proteinPhysical: mucus membraneConsist of a layer of epithelial cells bound by tight jucntioorsMucus membrane lines whatNose, mouth, lung, urinary and digestive tractepithelial cellsSecrete mucus that cover and protect fragile skin layersmucusviscous glycoproteins that trap microbes and prevent tracts from drying outciliated epithelial cellsUpper lining of respiratory tract Hair-like cilia Cilia movement moves debris mucus from lungsMucocliliary escalatorRemoval system with ciliated cellsPeristalsisthe process of wave-like muscle contractions of the alimentary tract that moves food along Moves mucus toendotheliaThe epithelial cells lining the urogenital tract, blood vessels, lymphatic vessels, and certain other tissuesPhysical: mechanical defensesPhysically remove. Pathogens Flushing action of ruin is tears Shedding skin Vomiting Diarrhea Mucus production EyelashesMicrobiomeResident microbiota serve as an important first line defense Compete fur cellular binding sites & nutrientschemical mediatorsWide array of substances found in various body fluids & tissue throughout the body work clone or with othersendogenously generatedProduced by humanexogenouslyproduced by certain microbes that are part of the microbiomesebumoily substance secreted by the sebaceous glands of the skin that lowers pH 3-5 Help seal off sweet glandsoleic acidCreates acidic environmentLactoperoxidase enzymesLysozymes ( ENZYMES)Destroys cell wall In tears, saliva mucus and urineLactoferrinInhibit microbial growth by chemically binding iron In tears, saliva mucus and urinecerumen (earwax)Forms protective film and lowers ph 3-5 of skin Earwax contains fatty acids that lower phvaginal secretionslow pH (3-5) inhibit microbesAntimicrobial peptides (AMPs)special class of nonspecific cell-derived mediators with broad-spectrum antimicrobial properties Some produced routinely by body other in response to invader pathogenAMPMay induce damage in micro organisms in different ways(AMP) DefensinsProduced by epithelial cells throughout the body Combat microorganisms by damaging their plasma membrane Macrophages and neutrophils(AMP) BacteriocinsSecreted by resident microbiota within gastrointestinal tract Disrupt membraneAMP - CathelicidinSecreted by epithelial cells i macrophages and other cells types inter ston Disrupts membrane Bacteria & fungiAMP - dermacidinSecreted by sweat gland Disrupts membrane and ion channel Bacteria & fungiAMP- HistatinsSalivary glands Oral cavity Fungi Disrupt intraccluler functionPlasmaFluid portion of bloodPlasma containselectrolytes and proteins and lipidsacute phase proteinsliver proteins that act as opsonins and that enhance the inflammatory response C reactive protein Serum amyloid A Ferritin Transferrincomplement systemA group of about 30 blood proteins that are actuated in a cascade: one triggers the next Circulate precursor proteinscomplement activationCirculating complement precursors become functional 3 diff trigger mechanisms: alternative classical lectinProtective outcomes of complement activation pathwaysOpsonization Inflammation Chemotaxis CotolysisOpsonizationCoating of apathogen bi chemical substance Allows phagocytic to reconnect, engulf, and destroyCytokinesSoluble protein communication signals between cells 3 Important classes interleukins chemokines and interferonsautocrine function of cytokinesaffect same cell responsible for their productionparacrine function of cytokinesRelease of cytokines affect nearby cellsEndocrine functionCells release cytokines into the bloodstream to be carried to call farther awayInterleukinsproteins (cytokines) that stimulate the growth of B and T lymphocytesChemokinesRecruit leukocytes oyctes to cites of infection, tissue damageInterferonsProtlens produced by cells Have antiviral activity Interferon- alpha and beta made and released by calls infected by virusinflammation eliciting mediatorsDestroy harmful agent or limits its effect on the body Repairs and replaces tissue damaged by harmful agent histamine, leukotrienes, prostaglandins, bradykininSigns of inflammationredness, heat, swelling, pain, loss of functionhematopoietic stem cellscell in the bone marrow that gives rise to all types of blood cellshematopoisesisprocess of blood cell formationmyeloid stem cellsgive rise to red blood cells, monocytes, neutrophils, eosinophils, basophils, and plateletslymphoid stem cellsbecome lymphocytes and natural killer cellsErythrocytesred blood cellsLeukocyteswhite blood cellsPlateletsblood clottingGranulocytesneutrophils, eosinophils, basophils, mast cells Distiguisted Bo appearance of nuclei and granule contentNeutrophilsPhagocytic Work in early steps of infection (pus)EosinophilsProtect against Protozoa and helminths Role n allergic reaction PhagocyticBasophilsrelease histamine Work in allergic responsesmast cellsCells that release chemicals (such as histamine) that promote inflammation.agranolocytesVisible granules in extoplasm lymphocytes and monocytesnatural killer cells (NK cells)Nonspecific to recognize and destroy cells that are abnormal m some way play an important role in the killing of cancer cells and cells infected by virusesLymphocytesRole in adaptive immunityMonocytesAn agranular leukocyte that is able to migrate into tissues and transform into a macrophage. Dendritic cellsPhagocytosisCells capacity of seek, ingest and kill pathogensExtravasation (diapedesis)escape of blood from the blood vessel into the tissuetransendothelial migrationSticking of phagocytes to blood vessels in response to cytokines at the site of inflammation flattening out and squeezing through cellular junction after "rolling adhesion"Pathogen recognitioninnate immune cells have receptors that recognize pathogens PAMPSPathogen-associated molecular patterns (PAMPs)Peptidoglycan: found in bacterial cell walls; -flagellin:, a protein found in bacterial flagella; -lipopolysaccharide: (LPS) from the outer membrane of gram-negative bacteria; -lipopeptides, molecules expressed by most bacteria; and -nucleic acids such as viral DNA or RNAphagosomephagocyte forms pseudopod that wraps around the pathogen and pinches it offPhagolysosomeacute inflammationMinimal and short-lasting injury to tissuevasoconstrictionRelated to the amount of vasuclery injury