host defenses 1: overview and innate immunity Flashcards

barriers that block invasion at the portal of entry

does not involve recognition of foreign substances

general in action

nonspecific

internalized system of protective cells and fluids

inflammation and phagocytosis

acts rapidly at the local and systemic levels

acquired on an individual basis as each foreign substance is encountered by lymphocytes

produces unique protective substances and cells that can come into play if the microbe is encountered again

provides long-term immunity

surveillance of the body

recognition of foreign material

destruction of entities deemed to be foreign

move throughout the body, searching for potential pathogens

trained to recognize self, or body cells, and non-self bacterial cells, or other invading pathogens

molecules on the surfaces of cells

composed of proteins and/or sugars

evaluated by cells of the immune system

many are a result of the immune system mistakenly attacking the body's own tissues and organs

the body attacks its own joints and tissues, causing pain and loss of function

PAMPs

markers that many different kinds of microbes have in common

PRRs

used by host cells with important roles in the innate immunity of the second line of defense to recognize PAMPs

found in spaces surrounding tissue cells

name given to extracellular spaces and their lymph fluid

transports products of a lymphatic reaction

a compartmentalized network of vessels, cells, and specialized accessory organs

provide an auxiliary route for return of extracellular fluid to the circularory system

act as a "drain-off" system for the inflammatory response

render surveillance, recognition, and protection against foreign materials, through a system of lymphocytes, phagocytes, and antibodies

plasmalike liquid carried by the lymphatic circulation

formed when certain blood components move out of the blood vessels into the extracellular spaces and diffuse or migrate into the lymphatic capillaries

transports numerous white blood cells, fats, cellular debris, and infectious agents that have gained access to tissue spaces

lymph moves in one direction only: from the extremities to the heart

lymph is only transported through the contraction of skeletal muscles

red bone marrow

thymus

lymph nodes

spleen

SALT, MALT, and GALT

typically found in the internal matrix of long bones and is the site of blood cell production

all blood cells originate in the bone marrow, including B- and T-lymphocyte precursors

B lymphocytes complete their maturation process while still in the bone marrow

site of T-cell maturation

triangular structure in the upper thoracic region

naive T lymphocytes mature at the thymus

small, encapsulated, bean-shaped organs

stationed in clusters along lymphatic channels and large blood vessels

filters out material that has entered the lymph and provides appropriate cells for immune reaction

loose connective tissue in armpit (auxiliary nodes)

groin (inguinal nodes)

neck (cervical nodes)

enlargement of lymph nodes reflects the replication of many lymphocyte clones during an adaptive immune response

may indicate the presence of a systemic illness

may be evidence of a localized infection

lymphoid organ in the upper left portion of abdominal cavity

serves as a filter for blood instead of lymph

remove worn-out red blood cells from circulation

filter pathogens from the blood for phagocytosis by macrophages

bundles of lymphocytes beneath the skin and mucosal surfaces all over the body

SALT

MALT

tonsils

breasts of pregnant women

GALT

clear, yellowish fluid

clear fluid from clotted blood often used in immune testing and therapy

production of blood cells

precursor to blood cells

pool undifferentiated, pluripotent cells

maintained in the bone marrow

immature or unspecialized cells develop the specialized form and function of mature cells

myeloid cells differentiate into erythroblasts and megakaryoblasts

lymphoid cells differentiate into myeloblasts and lymphoblasts

evaluated by reactions to hematologic stains that contain a mixture of dyes

cells differentiated by color and morphology

appear with or without colored granules in the cytoplasm

dark staining granules

do not have granules, large nucleus

support network of connective tissue fibers

reticular system

interconnects nearby cells

meshes with the massive connective tissue network surrounding all organs

give rise to macrophages and dendritic cells

reside near portals of entry or filtration organs, waiting to attack foreign intruders

liver (Kupffer cells)

lungs (alveolar macrophages)

skin (Langerhans cells)

brain (microglia)

products of monocytes, macrophages, lymphocytes, fibroblasts, mast cells, platelets, and the endothelial cells of blood vessels

IL-1 and TNF-B

comes from macrophages, B cells, dendritic cells

target B cells, T cells

comes from T cells

target phagocytes, tumor cells

IL-10

comes from T cells

target B cells, macrophages

serotonin and histamine

comes from platelets and intestinal cells

target cells in peripheral and central nervous system

comes from mast cells and basophils

target blood vessels, sensory nerves, neutrophils

IL-7 and erythropoietin

comes from bone marrow cells, epithelial cells

target stem cells

comes from endothelial cells

target stem cells

few pathogens can penetrate this unbroken layer

separates our inner bodies from microbial assaults of the environment

outer layers of skin are constantly sloughing off, taking associated microbes with them

epithelial cells compacted, cemented together, and impregnated with keratin

thick, tough layer that is highly impervious and waterproof

hair follicles and skin glands

hair shaft periodically extruded

follicle cells are desquamated

flushing effect of sweat glands helps remove microbes

digestive, urinary, and respiratory tracts, and the eye

moist and permeable

barrier protection without keratinized layer

impedes entry and attachment of bacteria

nasal hair traps larger particles

copious flow of mucus and fluids during allergies and colds exerts a flushing action

ciliated epithelium moves foreign particles entrapped in mucus toward the pharynx for removal

protection through the continuous trickle of urine through ureters and bladder emptying that flushes the urethra

vaginal secretions provide cleansing of the lower reproductive tract in females

provides microbial antagonism

blocks access of pathogens to epithelial surfaces

creates unfavorable environments for pathogens

found in tears and saliva

hydrolyzes peptidoglycan in cell walls of bacteria

hydrochloric acid

digestive juices and bile

to survey the tissue compartments and discover microbes, particulate matter, and injured or dead cells

to ingest and eliminate these materials

to recognize immunogenic information in foreign matter

neutrophils, monocytes, macrophages

react early in the inflammatory response to bacteria, foreign materials, and damaged tissue

common sign of bacterial infection is a high neutrophil count in the blood

primary component of pus

attracted to sites of parasitic infection and antigen-antibody reactions

play a minor phagocytic role

chemotaxis

ingestion

phagolysosome formation

destruction

excretion

peptidoglycan, lipopolysaccharide, double-stranded RNA found in viruses

a type of PRR

recognize PAMP

set in motion a cascade of events inside the host cell that amplifies and orchestrates a defense response to the pathogen

the phagocyte internalizes its prey

common reaction to any traumatic event in the tissues

readily identifiable by a classic series of signs and symptoms

redness; causes by increased circulation and vasodilation in injured tissues

warmth; heat given from the increased blood flow

swelling; from increased fluid escaping into the tissues

pain; caused by the stimulation of nerve endings

the fifth sign of inflammation

responsible for some chronic diseases, like cardiovascular disease

a feature of many autoimmune diseases

associated with many cases of long COVID-19

to mobilize and attract immune components to the site of the injury

to set in motion mechanisms to repair tissue damage and localize and clear away harmful substances

destroy microbes and block their further invasion

leakage of vascular fluid into tissue

local swelling and firmness due to accumulation of exudate into the tissues

blood-borne components that escape into extracellular space

movement of white blood cells from the bloodstream into the tissues

occurs because white blood cells are actively motile and able to change shape

receptors on endothelial cells capture WBCs and participate in their transport

influx of fluid dilutes toxic substances

fibrin clot can trap microbes and prevent further spread

neutrophils actively phagocytose and destroy bacteria, dead tissue, and particulate matter

attract monocytes, lymphocytes, and macrophages

macrophages clear pus, cellular debris, dead neutrophils and damaged tissue

B lymphocytes react with foreign molecules and produce antibodies

T lymphocytes kill intruders directly

tissue is completely repaired or replaced by a scar

an abnormally elevated body temperature

nearly universal symptom of infection

also associated with certain allergies, cancer, and other organic illnesses

100 to 101 degrees F

102 to 103 degrees F

104 to 106 degrees F

reset the hypothalamic thermostat to a higher setting (cause fever)

originating outside the body

products of infectious agents, such as viruses, bacteria, protozoans, and fungi

endotox

originating inside the body

released by monocytes, neutrophils, and macrophages during the process of phagocytosis

interleukin-1 (IL-1) and tumor necrosis factor (TNF)

difficult decision to suppress fever or not

slight to moderate fever in otherwise healthy person should be allowed to run its course

potential benefits and minimal side effects

small protein produced naturally by certain WBCs and tissue cells

used in therapy against certain viral infections and cancer

involved in defenses against viruses and other microbes and in immune regulation and intercommunication

alpha, beta, gamma

product of lymphocytes, fibroblasts, and macrophages

product of lymphocytes, fibroblasts, and macrophages

product of T cells

consists of over 50 blood proteins

work together to destroy bacteria and certain viruses

sequential physiological response

first substance in a chemical series activates the next substance, which activates the next, and so on until the desired outcome is reached

activated by antibodies bound to microbial surfaces

activated by lectins that bind to sugars on microbial surfaces

activated directly by repeating molecules on the microbial surface, such as LPS

initiation, amplification/cascade, polymerization, and membrane attack

short proteins capable of inserting themselves into bacterial membranes

between 12 and 50 amino acids

part of the innate immune system

have an effect on other actions of innate and adaptive immunity

molecules that can limit the ability of viruses to replicate once they are inside a host cell

can bind to certain parts of the virus

prevent synthesis of new virus parts, assembly of new virus, and release from host cell