Nonspecific immunity lecture 1 Flashcards
The first and second line defense are known as _____________. meaning that ____________________.
1) innate
2) your were born with them and they are nonspecific
the goal og the first line of defense is to ________________________.
Limit access
•First line of defense
- any barrier that blocks invasion at the _______________
- limits access to the ________________ of the body
- not considered a true immune response because ___________________________
1) portal of entry
2) internal tissues
3) it does not involve recognition of foreign substances; very general in action
•Second line of defense
- internalized system of protective _________________
- includes __________ and ____________.
- acts rapidly at both the local and systemic levels once ____________________.
1) cells and fluids
2) inflammation
3) phagocytosis
4) the first line of defense has been circumvented
•Third line of defense
- acquired on an individual basis as each foreign substance is encountered by _____________
- the reaction with each different microbe produces unique _________________
- provides ________________
1) lymphocytes
2) protective substances
3) long-term immunity
A First Line of Defense
•Inborn, nonspecific defenses can be divided into three types of barriers
- ___________
- ___________
- ___________
•These barriers impede the entry of microbes and other foreign agents, living or non-living
1) physical
2) chemical
3) genetic
Physical
•Skin
- _____________: tough outer layer that is impervious and waterproof
- constant sloughing of the outer layers of skin __________
- hair shaft is periodically shed and follicle cells are desquamated
- flushing effect of sweat __________________
1) stratum corneum
2) removes microbes
3) removes microbes
Physical
Mucous membranes of the digestive, urinary, and respiratory tracts and of the eye
- mucous coat impedes _______________ of bacteria
- blinking and tear production flush the ____________
- constant flow of saliva carries microbes to the _________
- ___________ and defecation evacuate noxious substances from the body
1) entry and attachment
2) eye’s surface
3) stomach
4) vomiting
Physical
•Respiratory tract
- _____________ larger particles
- copious flow of mucus and fluids provides flushing action
- _____________ conveys particles trapped in mucus toward the pharynx
- _____________ expels a large amount of air at high velocity
- foreign matter in the bronchi, trachea, and larynx triggers __________ to eject irritants
1) nasal hair traps
2) ciliated epithelium
3) sneeze reflex
4) coughing
Physical
•Genitourinary tract
- protection through the continuous trickle of ______________
- periodic bladder emptying flushes urethra
- ________________ provide cleansing of the lower reproductive tract in females
1) urine through ureters
2) vaginal secretions
Physical
•Resident microbiota
- trains host defenses so that commensals are kept in check and ____________ are eliminated
- interruptions in this process may lead to _____________ disturbances in the gut
- increased antibiotic use and efforts to free our environment from microbes may contribute to irritable bowel disease
- “____________” gut defense inappropriately responds to commensals
1) pathogens
2) immunologic
3) ill-trained
Nonspecific Chemical Defenses
- Sebaceous secretions exert an ________________
- Specialized glands of the eyelids lubricate the conjunctiva with an ____________________
- ___________: an enzyme found in tears and saliva that hydrolyzes the peptidoglycan in the cell wall of bacteria
- ______________ and electrolyte content of sweat
- Acidic pH and fatty acid content of the skin
1) antimicrobial effect
2) antimicrobial secretion
3) Lysozyme
4) High lactic acid
Nonspecific Chemical Defenses (cont’d)
- ________________ in the stomach gives protection against microbes that are swallowed
- Digestive juices and bile in the intestine are __________ to microbes
- Semen contains an _____________________
- Vagina has a protective acidic pH maintained by ________
1) Hydrochloric acid
2) destructive
3) antimicrobial chemical
4) normal flora
Genetic Differences in Susceptibility
- Differences in susceptibility can arise in mutations in the genes that code for components of the immune system
- Loss of immunity or absence of normal immunity demonstrate the vital need for barriers of all types
- patients with severe burns are very susceptible to all kinds of infections
- blockages in salivary glands, tear ducts, intestine, and urinary tract are at greater risk
- patients with severe burns are very susceptible to all kinds of infections
The first line of defense alone is not sufficient protection: inflammation, phagocytosis, and specific immune responses are necessary
The Second and Third Lines of Defense:
Immunology is the
- the study of all features of the body’s _______________________.
- study of the body’s response to _______________
- study of ________________
1) second and third lines of defense
2) infectious agents
3) allergies and cancer
A healthy, functioning immune system is responsible for the following
- _________________ (Ex. CCO’s doing rounds)
- recognition of _________________
- destruction of entities deemed to be foreign
1) surveillance of the body
2) foreign material
___________________ constantly move throughout the body, searching for potential pathogens
- recognize body cells (self)
- differentiate them from any foreign material in the body (nonself)
- the ability to evaluate ________________ as self or nonself is central to the functioning of the immune system
- many ____________________ are a result of the immune system mistakenly attacking the body’s own tissues and organs
1) White blood cells
2) macromolecules
3) autoimmune disorders (when your body does not recognise self from nonself)
Amino-compitent means ________________________
you have a good functioning immune system.
(opposite to amino-compromise)
cells have various markers, called ______________
antigens
pathogen associated molecular patterns (pamp’s) is a ________________________________
generic bacteria found in pathogens and viruses
The immune system evaluates cells by examining molecules on cell surfaces called ___________
- consist of _____________________
- allow cells of the immune system to identify whether a newly discovered cell poses a threat and should be marked for destruction
- nonself proteins that are _____________ are generally recognized as such (allergies)
1) markers
2) proteins and/or sugars
3) not harmful
•Whole blood consists of
- blood cells: ________________
- plasma: _______________
- serum: ___________________________
1) formed elements
2) clear, yellowish fluid
3) essentially the same as plasma, except that it is the clear fluid from clotted blood; used in immune testing and therapy
The Second Line of Defense
Generalized and nonspecific defenses that support and interact with specific immune responses (accomplished by)
- _______________
- _______________
- _______________
- _______________
1) phagocytosis
2) inflammation
3) fever
4) antimicrobial proteins
Phagocytosis: Cornerstone of Inflammation and Specific Immunity
General activities of phagocytosis are
- survey the tissue compartments and discover microbes, particulate matter, and injured or dead cells
- ___________________ these materials
- extract ______________ information
1) ingest and eliminate
2) immunogenic (relating to or denoting substances able to produce an immune response)
what are the three Professional phagocytes?
- _______________
- _______________
- _______________
1) neutrophils
2) monocytes
3) macrophages
Neutrophils
- General purpose phagocytes
- React early in the inflammatory response to bacteria and other foreign materials and to damaged tissue
- High neutrophil count in the blood is a common sign of _________________
- Primary component of _______
1) bacterial infection
2) pus
•______________ are transformed into _______________ after they migrate out of the bloodstream and into the tissues
1) Monocytes
2) macrophages
•________________: live in a certain tissue and remain there during their lifespan
- alveolar (lung) macrophages
- Knupffer cells in the liver
- dendritic cells in the skin
- macrophages in the spleen, lymph nodes, bone marrow, kidney, bone, and brain
1) Histiocytes
Monocytes and Macrophages (cont’d)
- Other macrophages do not reside permanently in tissue, but drift nomadically throughout the _____________________
- Dynamic scavengers
- Process foreign substances and prepare them for reactions with B and T lymphocytes
1) RES (Reticuloendothelial System)
- Phagocyte: “_____________”
- Phagocytosis
- physical process of ____________
- attack and dismantling of foreign cells
- can be an isolated event or as part of the orchestrated events of _____________
1) eating cell
2) engulfment
3) inflammation
how does Phagocytosis form?
- _____________
- _____________
- _____________
- _____________
- _____________
1) Chemotaxis
2) Ingestion
3) Phagolysosome formation
4) Destruction
5) Excretion
_______________: migration of cells in response to a specific chemical stimulus
chemotaxis
Pathogen-associated molecular patterns (PAMPs)
- signal molecules found on microbial surfaces recognized by phagocytes and other defensive cells
- molecules shared by many organisms, but not present in __________
- serve as “red flags” for phagocytes and other cells of innate immunity
- bacterial PAMPs: ___________________________
- viral PAMPs: ___________________
1) mammals
2) peptidoglycan and lipopolysaccharide
3) double-stranded RNA
Phagocytosis
Pattern Recognition Receptors (PRRs)
- found on phagocytes, dendritic cells, endothelial cells, and lymphocytes
- recognize and bind to ___________
- cells possess PRRs whether they have encountered ________________
1) PAMPs
2) PAMPs before or not
Easily identifiable by a classic series of signs and symptoms
- rubor: _________________________________
- calor: _________________________________
- tumor: __________________________________
- dolor: ___________________________________
- loss of function
1) redness caused by increased circulation and vasodilation in the injured tissue
2) warmth caused by the heat given off by the increased flow of blood
3) swelling caused by fluid escaping into the tissues
4) pain caused by the stimulation of nerve endings
The Inflammatory Response (cont’d)
- Some chronic diseases, such as ___________________, are caused by chronic inflammation
- Can be local or systemic
- Some researchers believe that aging is a consequence of increasing inflammation in multiple body systems
- Factors that elicit inflammation
- trauma from ________
- tissue injury or __________ due to physical or chemical agents
- specific immune reactions
1) cardiovascular disease
2) infection
The Inflammatory Response (cont’d)
•Chief functions of inflammation
- to ____________________ immune components to the site of injury
- to set in motion mechanisms to repair tissue damage and localize and clear away ___________________
- destroy microbes and block their further _____________
1) mobilize and attract
2) harmful substances
3) invasion
The Role of Inflammatory Mediators
Cytokines
- hundreds of small active molecules secreted to regulate, stimulate, suppress, and otherwise control many aspects of cell development, inflammation, and immunity
- produced by __________________________________
- effects may be local or systemic, short term or long lasting, specific or nonspecific, protective or pathologic
monocytes, macrophages, lymphocytes, fibroblasts, mast cells, platelets, and endothelial cells
The Stages of Inflammation
- Process leading to inflammation is a dynamic, predictable series of events lasting from a few minutes to a few hours or days
- Once the initial injury has occurred, a chain reaction takes place at the site of damaged tissue, summoning ________________ to the injured area
beneficial cells and fluids
•Diapedesis
- the _________________ out of blood vessels into tissues
- ______ are actively motile and readily change shape
- endothelial cells lining venules contain complex adhesive receptors that capture WBCs and transport them into ______________.
1) migration of WBCs
2) WBCs
3) intracellular spaces
•Chemotaxis
- migration of cells in response to a ___________________
- cells swarm from many compartments to the site of infection and remain there to perform _________________ immune functions
1) specific chemical stimulus
2) general and specific
The Benefits of Edema and Leaky Vessels
- Influx (incoming) of fluid _______________ substances
- ____________ can trap microbes to prevent further spread
- ____________ aggregated at the inflamed site are involved in phagocytosing and destroying bacteria
1) dilutes toxic
2) Fibrin clot
3) Neutrophils
•_______________: the accumulation of a whitish mass of cells, liquefied cellular debris, and bacteria
1) Pus
_______________: bacteria such as streptococci, staphylococci, gonococci, and meningococci that stimulate the formation of pus
Pyogenic
Fever: __________________
•Abnormally elevated body temperature
- -nearly universal symptom of infection
- -associated with certain allergies, cancers, and other organic illnesses
An Adjunct to Inflammation
•Fevers of unknown origin (FUO)
- intermittent fever greater _________________
- lasting longer than 3 weeks for which no known cause can be determined after 1 week of inpatient investigation
1) than 38°C (101°F)
Body temperature is maintained at 37°C (98.6°F) by the _______________
- ________________: 37.7 – 38.3°C or 100 – 101°F
- High fever: 40.0 – 41.4°C or 104 – 106°F
1) hypothalamus
2) Low grade fever
•________________: substances that reset the hypothalamic thermostat to a higher setting
Pyrogens
-__________________: products of infectious agents such as viruses, bacteria, protozoans, fungi, endotoxin, blood, blood products, vaccines, or injectable solutions
exogenous pyrogens
-_________________: liberated by monocytes, neutrophils, and macrophages during phagocytosis such as interleukin-1 and tumor necrosis factor
endogenous pyrogens
Benefits of Fever
- Inhibits multiplication of temperature-sensitive microorganisms such as the poliovirus, cold viruses, herpes zoster virus, and systemic and subcutaneous fungal pathogens
- Impedes nutrition of bacteria by reducing the availability of iron
- Increases metabolism and stimulates immune reactions and naturally protective physiological processes
- speeds up hematopoiesis, phagocytosis, and specific immune reactions
Treatment of Fever
- Benefits of fever make it a difficult decision whether to treat or not to treat
- Slight to moderate fever in an otherwise healthy person should be allowed to run its course
- Side effects
- ____________: rapid heart rate
- ____________: elevated respiratory rate
- lowering of seizure threshold
•Medical experts agree that high and prolonged fevers in individuals with cardiovascular disease, seizures, or respiratory ailments should be treated immediately
1) tachycardia
2) tachypnea
Antimicrobial Proteins: ____________
- A small protein produced naturally by certain __________________
- Originally thought to be directed against viruses, but is involved in defenses against microbes and immune regulation and intercommunication
1) Interferon
2) white blood and tissue cells
_____________ produced by lymphocytes, fibroblasts, and macrophages
Interferon alpha and beta
•________________: produced by T cells
Interferon gamma
______________: produced by T cells
Interferon gamma
Biological activities of interferon
- bind to cell surfaces and induce changes in genetic expression; exact results vary
- all three IFNs can inhibit the expression of cancer genes and have tumor suppressor effects
- IFN alpha and beta stimulate ____________
- IFN gamma is the immune regulator of ______________________
1) phagocytes
2) macrophages and T and B cells
Characteristics of Interferon
- Binding of viruses and other microbes to receptors on a host cell, signals the cell to _________________
- Interferon molecules are rapidly secreted into the extracellular space, binding to other host cells
- Binding of interferon induces the production of proteins in the cell that inhibit viral multiplication
- _______________
- _______________
- Not microbe-specific
- Valuable treatment for a number of virus infections
1) produce interferon
2) degrade viral RNA
3) prevent translation of viral proteins
Antimicrobial Proteins: ________________
- Named for its property of “________________” immune reactions
- Consists of ________________ that work in concert to destroy bacteria and certain viruses
1) Complement
2) complementing
3) 26 blood proteins
________________
- sequential physiological response
- first substance in a chemical series activates the next substance, which activates the next, and so on
•Three different pathways distinguished by how they are activated; all have the same end result
Cascade reaction
Overall Stages in the Complement Cascade
- _____________: C1 components bind to an initiator bound to a foreign cell
- ____________________: C1 leads to C5 being cleaved and bound to the membrane
- _____________: C5 product becomes the site for the assembly of the membrane attack complex
- ________________: C5 – C9 form the membrane attack complex that punctures pores in the cell membrane, leading to lysis
1) Initiation
2) Amplification and cascade
3) Polymerization
4) Membrane attack
The Complement Cascade (cont’d)
- _________________: initiated either by the foreign cell membrane of a parasite or a surface antibody
- _________________
- activated when components of the complement pathway recognize and bind to pathogen membranes
- quicker response than the classical pathway
- _________________: mannose binding proteins (lectins) must bind to mannose residues on the surface of pathogens in order for the pathway to proceed
1) Classical pathway
2) Alternative pathway
3) Lectin pathway
Antimicrobial Proteins: Iron-Binding Proteins
•_____________________ require iron for their enzymes
- becomes a rate-limiting factor in bacterial growth
- iron-binding proteins keep available iron bound so tightly that it cannot be used by bacteria
Humans and bacteria
Iron-Binding Proteins (cont’d)
- _____________: found in red blood cells
- _____________: found in blood and tissue fluids
- _____________: found in milk and saliva
- _____________: found in every cell type
- _____________:
- proteins produced by bacteria capable of scavenging iron from iron-binding proteins
- bind iron more tightly than human proteins
1) Hemoglobin
2) Transferrin
3) Lactoferrin
4) Ferritin
5) Siderophores
Antimicrobial Proteins: Antimicrobial Peptides
- Short proteins of ________ amino acids
- Able to insert themselves into prokaryotic membranes to kill ___________
- Defensin, magainins, protegrins
- Also have an effect on other actions of nonspecific and specific immunity
- Researchers are looking for ways to turn these antimicrobial peptides into therapeutic drugs
1) 15 – 20
2) microbes
