Ch. 12: Host Defenses-Innate

What host defense is intrinsic to you, meaning that it is already inside your system, like inflammation?

innate immunity

What host defenses is aquired meaning you get it throughout your life?

adaptive immunity

What line of defense is surface protection composed of, anatomical and physiological barriers that keep microbes from penetrating sterile body components?

first line of defense 

How long does the first line of defense take to start?

0-4hrs

What line of defense is a cellular and chemical system that comes immediately into play if infectious agents make it past the surface defenses?

second line of defense

How long does it take for the second line of defense to start?

4-96hrs

What line of defense includes specific host defenses that must be developed uniquely for each microbe through the action of specialized WBCs?

third line of defense 

How long does it take for the third line of defense to start?

>96hrs

What line of defense is innate, any barrier that blocks invasion at the portal of entry, limiting access in a general action?

first line

What line of defense is innate, an internal system of protective cells and fluids, including inflammation and phagocytosis, that acts rapidly at both local and systemic levels once at the first line is breached?

second line

What line of defense is acquired as each foreign substance is encountered by lymphocytes, where each different microbe produces a unique protective response, providing long-term immunity?

third line 

What are the three barriers of the first line of defense?

physical or mechanical barriers: skin and mucous membrane, chemical (enzymes) or physiological (secretions) barriers, microbiological (microbiome) barriers

What barrier of the first line of defense has its outermost layer that is impervious and waterproof, also sheds to remove microbes?

skin

What barrier of the first line of defense has a coating that impedes the entry and attachment of bacteria?

mucous membranes 

What part of the mucous membrane uses blinking and tearing?

eye 

What part of the mucous membrane uses a constant flow of saliva to carry microbes to the harsh conditions of the stomach and vomiting and defecation to evacuate noxious substances or microorganisms from the body? 

digestive 

What part of the mucous membrane uses nasal hair to trap microbes, the flow of mucus and fluids to flush, ciliated epithelium conveys particles trapped in mucous towards the pharynx, sneeze reflex to expel, and coughing to eject foreign matter?

respiratory 

What is it called when ciliated epithelium conveys particles trapped in mucus towards the pharynx?

ciliary escalator

What barrier of the first line of defense uses excretions to exert antimicrobial effects, glands of eyelids as lubrication, lysozymes, high lactic acid, and electrolytes concentration of sweat, acidic pH of the skin, HCl acid in the stomach?

chemical or physiological barriers 

What is an enzyme found in tears and saliva that hydrolyzes the peptidoglycan in the cell wall of bacteria?

lysozyme 

What barrier of the first line of defense blocks access of pathogens to epithelial surfaces or attachment sites, creates competition for limited nutrients because they are present in large numbers, and creates an unfavorable environment for pathogens by altering the local pH?

microbiological barrier - human microbiome 

What are the 4 parts of the second line of defense?

phagocytosis, inflammation, fever, antimicrobial proteins

What is the cornerstone of inflammation?

phagocytosis

What cell has the general fx of surveying the tissue compartments and discovering particulate matter and injured or dead cells, ingesting and eliminating these materials, and reading immunogenic information, and can be in an isolated event or part of inflmmation?

phagocytes 

What are the types of phagocytes?

neutrophil, monocytes, macrophages, dendritic cells

What type of phagocyte is in large numbers in WBCs, in the blood, 1st responders at the site of inflammation, a high count of these in the blood is a sign of bacterial infection, and primary component of pus?

neutrophils

What type of phagocyte is in the blood, not good at phagocytosis, 2nd responders of inflammation, differentiates into macrophages after they move out of the bloodstream and into the tissues, some live in certain tissues and are named based on their location?

macrophages

What type of macrophage lives in the lungs?

alvelor 

What type of macrophages live in the liver?

kupffer 

Where do macrophages live?

liver, lung, spleen, lymph nodes, bone marrow, kidney, bone, and brain 

What types of phagocytes are in tissues and good at phagocytosis?

macrophages and dendritic cells 

What step of phagocytosis is 1st, when phagocytes migrate into the region of inflammation with a deliberate sense of direction, attracted by a gradient of stimulant products from the parasite and host tissue at the site of injury?

chemotaxis

What step of phagocytosis is the 2nd, when phagocytes use their PRRs to recognize PAMPs on foreign targets and causes phagocyte to attach ti its target microbe?

adhesion

What step of phagocytosis is the 3rd step, when it extends pseudopods around its target and internalizes it in a vacuole called a phagosome, and secretes more cytokines to further amplify the innate response?

engulfment and phagosome formation 

What step of phagocytosis is the 4th step, when lysosomes fuse with a phagosome (containing captured target) to form a phagolysosome, where antimicrobial chemicals are released into forming a toxic brew designed to poison and dismantle the ingested material?

phagolysosome formation and killing 

What step of phagocytosis is when two systems of destructive chemicals wait for the microbes in the phagolysosome, like the oxygen-dependent system, which is the formation of several derivatives of oxygen, like superoxide and hydrogen peroxide, or enzymes like DNAase or RNAase, proteases?

destruction 

What step of phagocytosis is when small bits of undigestible debris are released from the macrophage by exocytosis?

elimination 

What are molecules found on microbial surfaces that are recognized by phagocytes, aren’t present in mammals, aka “reg flags” for phagocytosis?

pathogen-associated molecular patterns (PAMPs)

What are bacterial PAMPs made of?

peptidoglycan and lipopolysaccharide

What are viral PAMPs made of?

double stranded RNA

What are found on immune cells (endothelial cells), that recognize and bind to PAMPs?

pattern recognition receptors (PRRs)

What part of the second line defense invites phagocytic cells to a site, which can be local or systemic, elicited from trauma from infection, or tissue injury?

inflammation

What s/s of inflammation is redness caused by increased circulation and vasodilation?

rubor 

What s/s of inflammation is warmth caused by heat given off by increased flow of blood?

calor

What s/s of inflammation is swelling/edema caused by fluid escaping into the tissues?

tumor

What s/s of inflammation is pain caused by stimulation of nerve endings?

dolor

What s/s of inflammation is not always present?

loss of function

What are the chief functions of inflammation?

mobilize and attract immune compents to site of injury, destroy microbes and block their further invasion, set in motion mechanisms to repair tissue damage, and localize and clear away harmful substances

When do reactions in inflammation occur in damaged tissue, which include the release of chemical mediators and cytokines by the blood cells, tissue cells in the injured area happen?

immediate 

What are mediators in inflammation that affect the endothelial cells and smooth muscles of blood vessels?

vasoactive 

What are mediators in inflammation that affect the WBCs?

chemotactic factors (chemokines)

What releases the chemical mediators in inflammation, like cytokines and histamines?

mast cells

What is the 1st step of inflammation, where blood vessels in the vicinity dilate, increasing the flow of blood into the area?

vasodilation 

What is the 2nd step of inflammation, where endothelial cells in the walls of blood vessels contract and form gaps through which some blood components exude and form an accumulation of fluid called exudate, giving rise to local swelling called edema?

increased permeability

What is the 3rd step of inflammation, where there is migration of WBCs out of blood vessels into tissues: neutrophils first and macrophages later?

diapedesis 

What is the 4th step of inflammation, where there is migration of cells in infected tissue in response to a specific chemical stimulus?

chemotaxis and phagocytosis 

What is the 5th step of inflammation, where damaged tissues are fixed?

repair

What are the benefits of edema and leaky blood vessels?

dilute toxic substances, clots block and prevent the spread of microbes, neutrophils aggregated at the inflmated site are involved in phagocytosis and destroying bacteria, dead tissue, and particulate matter 

What is the accumulation of dead WBCs, liquefied cellular debris and bacteria?

pus

What are bacteria such as streptococci, staphylococci, gonococci and meningococci that stimulate the formation of pus?

pyogenic 

What is a systemic response where a person has an abnormally elevated body temperature, which is a universal symptom of infection, associated with certain allergies, cancers and other illnesses?

fever

What do you call a fever if the cause is unknown?

fever or unknown origin (FUO)

What regulates the body to maintain around 37 degree Celsius or 98.6 degrees Fahrenheit?

hypothalamus

What is a substance that resets the hypothalmic thermostat to a higher setting?

pyrogens

What is a pyrogen that is a product of pathogens such as viruses, bacteria, protozoans, fungi, endotoxin, blood, blood products, vaccines, or injectable solutions coming from outside the body?

exogenous pyrogens

What is a pyrogen that is liberated by monocytes, neutrophils, and macrophages during phagocytosis, such as interleukin-1 (IL-1) and tumor necrosis factor (TNF), which are made in our bodies to increase body temperature?

endogenous pyrogens

What are the benefits of fever?

inhibits the multiplication of temperature-sensitive microorganisms, and speeds up hemopoiesis, phagocytosis, and specific immune reactions

What is the antimicrobial product that is a small protein produced naturally by white blood and tissue cells that make alpha and beta interferons?

interferon 

What is do alpha and beta interferons do?

antiviral activity

What do infected cells produce to tell other cells their is a pathogen that they need to fight off?

interferon IFN

What is in a nearby cell of an infected cell so they are able to slow the synthesis of the virus?

antiviral proteins

What is the antimicrobial product that complements the immune response, made of over 30 blood pathogens that work together to kill pathogens, but needs to be activated?

complement

What complement activation is when the first complement protein in a chemical series activates the next complement, which activates the next, and so on?

sequential activation

What complement pathway is initiated by binding to the antibodies that are already bound to the microbes (need pathogen and antibody)?

classical complement pathway

What complement pathway does not require an antibody to get started and is a quicker response (needs pathogen but not antibody)?

alternative complement pathway 

What are the 3 functions of complement proteins?

opsonization, inflammation, MAC and lysis

What function of the complement proteins is when the C3 protein is hydrolyzed into C3b and C3a, and C3b coats the surface of a microbe, making it an easier target for phagocytosis?

opsonization

What function of complement proteins is when C3b proteins cleaves the protein C5 into C5a and C5b where C5a aids inflammation?

inflammation

What function of complement protein sis when the C5b fragment is free to form a complex with C6, C7, C8, C9 called the membrane attack complex?

MAC and lysis 

What complex forms pores in the target cell’s membrane causing it to lose structural integrity, leading to the flow of water and ions in and out of the cell, eventually leading to lysis of the cell?

membrane attack complex (MAC)

What microbial product is made of short proteins of 12-50 AA, like defensin, which inserts themselves into bacterial membranes, making a pore, and if enough forms, the cell will lyse?

antimicrobial peptides (AMP)