Shared Flashcard Set

Details

Immuno Readings
UC MED 2015
67
Medical
Graduate
03/04/2012

Additional Medical Flashcards

 


 

Cards

Term
What is defined as resistance to disease, specifically infectious disease?
Definition
Immunity
Term
What refers to the fact that this type of host defense is always present in healthy individuals, prepared to block the entry of microbes and to rapidly eliminate microbes that do succeed in entering host tissues?
Definition
Innate Immunity
Term
What is the type of host defense that is stimulated by microbes that invade tissues, that is, it adapts to the presence of microbial invaders?
Definition
Adaptive Immunity
Term
What are a class of lymphocytes that recognize infected and stressed cells and respond by killing these cells and by secreting the macrophage-activating cytokine IFN-γ?
Definition
NK cells
Term
What activates the macrophages to kill phagocytosed microbes?
Definition
interferon-γ (IFN-γ)
Term
What do macrophages secrete to actiavte NK to secrete IFN-γ?
Definition
IL-12
Term
What cells are the principal mediators of ADCC and what does it stand for?
Definition
-NK cells
-antibody-dependent cellular cytotoxicity
Term
Most healthy cells express what that inhibitory receptors on NK cells recognize so taht an immune response is not mounted against them?
Definition
MHC class I self molecules
Term
NK-activating cytokines are
Definition
interleukin-15 (IL-15), type I interferons (IFNs), and IL-12
Term
What important for the development and maturation of NK cells?
Definition
IL-15
Term
What enhance the killing functions of NK cells?
Definition
-IL-12
-IFNs
Term
What is triggered when some complement proteins are activated on microbial surfaces and cannot be controlled, because complement regulatory proteins are not present on microbes (but are present on host cells)? This pathway is a component of innate immunity.
Definition
Alternate pathway
Term
What is triggered after antibodies bind to microbes or other antigens and is thus a component of the humoral arm of adaptive immunity?
Definition
Classical pathway
Term
What is activated when a plasma protein, mannose-binding lectin, binds to terminal mannose residues on the surface glycoproteins of microbes? This lectin activates proteins of the classical pathway, but because it is initiated by a microbial product, in the absence of antibody, it is a component of innate immunity.
Definition
Lectin pathway
Term
The central component of complement is a plasma protein called...
Definition
C3
Term
What becomes covalently attached to microbes and is able to activate downstream complement proteins on the microbial surface?
Definition
C3b
Term
The three pathways of complement activation differ in how they are initiated, but
Definition
they share the late steps and perform the same effector functions.
Term
What initiates the late steps of complement activation, culminating in the production of numerous peptides and polymerized C9?
Definition
C3b
Term
What forms the membrane attack complex, so called because it creates holes in plasma membranes?
Definition
C9
Term
The complement system serves three functions in host defense...
Definition
1)C3b coats microbes and promotes the binding of these microbes to phagocytes, by virtue of receptors for C3b that are expressed on the phagocytes. Thus, microbes that are opsonized with complement proteins are rapidly ingested and destroyed by phagocytes.
2)Some proteolytic fragments of complement proteins, especially C5a and C3a, are chemoattractants for phagocytes, and they promote leukocyte recruitment (inflammation) at the site of complement activation.
3)Complement activation culminates in the formation of a polymeric protein complex that inserts into the microbial cell membrane, disturbing the permeability barrier and causing either osmotic lysis or apoptotic death of the microbe.
Term
What are soluble proteins that mediate immune and inflammatory reactions and are responsible for communications between leukocytes and between leukocytes and other cells?
Definition
Cytokines
Term
In innate immunity, the principal sources of cytokines are...
Definition
-Dendritic cells
-macrophages
Term
Cytokines act on the cells that produce them is called?
Definition
autocrine action
Term
Cytokines act on adjacent cells is called?
Definition
paracrine action
Term
Cytokines act on the cells that are distant from the site of secretion is called?
Definition
endocrine action
Term
What are the principal cytokines involved in recruiting blood neutrophils and monocytes to sites of infection?
Definition
-TNF
-IL-1
-chemokines
Term
What in high concentrations promotes thrombus formation on the endothelium and reduces blood pressure by a combination of reduced myocardial contractility and vascular dilatation and leakiness?
Definition
TNF
Term
What is characterized by low blood pressure (the defining feature of shock), disseminated intravascular coagulation, and metabolic disturbances?
Definition
Septic shock
Term
The early clinical and pathologic manifestations of septic shock are caused by very high levels of?
Definition
TNF
Term
What is a protein that recognizes microbial carbohydrates and can coat microbes for phagocytosis or activate the complement cascade by the lectin pathway?
Definition
mannose-binding lectin (MBL)
Term
What binds to phosphorylcholine on microbes and coats the microbes for phagocytosis by macrophages, which express a receptor for this?
Definition
C-reactive protein (CRP)
Term
The innate immune system can also recognize molecules that are released from stressed or necrotic cells. The subsequent response serves to eliminate these cells. Such molecules have been grouped under...
Definition
damage-associated molecular patterns (DAMP)
Term
What is essential for responses to several bacterial lipoglycans?
Definition
TLR-2
Term
What is essential for viral nucleic acids (such as double-stranded RNA)?
Definition
TLR-3,7,8
Term
What is essential for bacterial LPS (endotoxin)?
Definition
TLR-4
Term
What is essential for a component of bacterial flagella called flagellin?
Definition
TLR-5
Term
What is essential for unmethylated CG-rich (CpG) oligonucleotides, which are more abundant in bacteria than in mammalian cells?
Definition
TLR-9
Term
What TLR receptor promotes expression of various cytokines and endothelial adhesion molecules?
Definition
NF-κB (nuclear factor κB)
Term
What TLR receptor stimulates production of type I interferons, cytokines that block viral replication?
Definition
IRF-3 (interferon response factor-3)
Term
The two types of circulating phagocytes, ___________ and ____________, are blood cells that are recruited to sites of infection, where they recognize and ingest microbes for intracellular killing
Definition
neutrophils and monocytes
Term
What are the first cell type to respond to most infections, particularly bacterial and fungal infections. They ingest microbes in the circulation, and they rapidly enter extravascular tissues at sites of infection, where they also ingest microbes and die after a few hours.
Definition
Neutrophils
Term
What refers to the proliferation of cells and tissues to replace lost structure?
Definition
regeneration
Term
What most often consists of a combination of regeneration and scar formation by the deposition of collagen?
Definition
repair
Term
Scar formation is the predominant healing process that occurs when what is damage?
Definition
ECM (extra-cellular matrix)
Term
What else stimulates scar formation?
Definition
chronic inflammation that accompanies persistant injury
Term
ECM components are essential for wound healing, because they provide...
Definition
1) Framework for cell migration
2) Maintain the correct cell polarity for the re-assembly of multilayer structures
3) Participate in the formation of new blood vessels (angiogenesis)
4) Cells in the ECM (fibroblasts, macrophages, and other cell types) produce growth factors, cytokines, and chemokines that are critical for regeneration and repair.
Term
Repair by connective tissue deposition includes the following basic features:
Definition
• inflammation
• angiogenesis,
• migration and proliferation of fibroblasts,
• scar formation
• connective tissue remodeling
Term
The relative contributions of repair and regeneration are influenced by:
Definition
(1) the proliferative capacity of the cells of the tissue
(2) the integrity of the extracellular matrix
(3) the resolution or chronicity of the injury and inflammation
Term
What are the 3 phases of cutaneous wound healing?
Definition
1) Inflammation
2) Proliferation
3) Maturation
Term
The initial injury causes platelet adhesion and aggregation and the formation of a clot in the surface of the wound, leading to...
Definition
inflammation
Term
In what phase there is formation of granulation tissue, proliferation and migration of connective tissue cells, and re-epithelialization of the wound surface?
Definition
Proliferative
Term
What phase involves ECM deposition, tissue remodeling, and wound contraction?
Definition
maturation phase
Term
What are 2 keys in the inflammation phase?
Definition
-clot formation
-chemotaxis
Term
What are 3 keys in the proliferation phase?
Definition
-Re-epithelization
-Angiogenesis and granulation tissue
-Provisional matrix
Term
What are 2 keys in the maturation phase?
Definition
-Collagen matrix
-Wound contraction
Term
The clot contains?
Definition
-entrapped RBCs
-fibrin
-fibronectin
-complement components
Term
In 48 to 96 hours after injury, neutrophils are largely replaced by what cell type?
Definition
macrophages
Term
What do macrophages do in wound healing? What factors for these things?
Definition
1) Debridement; Removal of injured tissues and debris (Phagocytosis, cooagenase, elastase)
2) Antimicrobial activity (Nitric acid, ROS)
3) Chemotaxis and proliferation of fibroblasts and keratinocytes (PDGF, TGF-ß, TNF, IL-1, KGF-7)
4) Angiogenesis ( VEGF, FGF-2, PDGF)
5) Deposition and remodeling of ECM (TGF-ß, PDGF, TNF, OPN, IL-1, collagenase, MMPs)
Term
What is produced by most of the cells in granulation tissue and causes fibroblast migration and proliferation, increased synthesis of collagen and fibronectin, and decreased degradation of ECM by metalloproteinases?
Definition
TGF-ß
Term
By the end of the first month, the scar is made up of...
Definition
acellular connective tissue devoid of inflammatory infiltrate, covered by intact epidermis
Term
Where does wound contraction occur?
Definition
Large surface wounds
Term
What helps to close the wound by decreasing the gap between its dermal edges and by reducing the wound surface area?
Definition
Wound contraction- key to healing in secondary union
Term
What are the systemic factors that influence the quality and adequacy of wound healing?
Definition
1) Nutrition
2) Metabolic status
3) Circulatory status
4) Hormones
Term
What are the local factors that influence the quality and adequacy of wound healing?
Definition
1) Infection
2) Mechanical factors
3) Foreign bodies
4) Size, location, and type of wound
Term
The accumulation of excessive amounts of collagen may give rise to a raised scar known as a...
Definition
hypertrophic scar
Term
if the scar tissue grows beyond the boundaries of the original wound and does not regress, it is called a?
Definition
keloid
Term
What is used more broadly to denote the excessive deposition of collagen and other ECM components in a tissue?
Definition
fibrosis
Supporting users have an ad free experience!