immune/lymphatic system

what is a pathogen?

disease causing organisms

the lymphatic system includes…

cells, tissue and organs

what are the primary cells of the lymphatic system?

lymphocytes

what do lymphocytes do?

vital to the to the body’s ability to resist/overcome infection and disease

immunity is what?

the ability to resist infection and disease

what is innate (nonspecific) defense?

born with it, do not distinguish one potential threat from another

what is adaptive (specific) defense?

organize a defense against a particular type of bacterium, defense against specific antigens do not distinguish one potential threat from another

what is immune response?

defense against specific antigens

name the four components of the lymphatic system

vessels, fluid, lymphocytes and lymphoid tissue/organ

vessels are also called what?

lymphatics

what is fluid called?

lymph

what are lymphoid tissues?

collections of loose connective tissue and lymphocytes in structures called lymphoid nodules

whats an example of a lymphoid nodules?

tonsils

what are lymphoid organs?

complex structures containing lymphocytes and are connected lymphatic vessels

what are examples of lymphoid organs?

spleen and lymph nodes

what are secondary lymphoid tissues/organs?

where lymphocytes are activated/cloned

pressure within the lymphatic system are extremely low, so the valves are essential to maintaining normal what?

lymph flow

the lymphatic vessels empty into 2 large collecting structures called

lymphatic ducts

thoracic duct collects lymph from the (6 places)

lower abdomen, pelvis, lower limbs, LEFT half of the head, neck and chest

the right lymphatic duct is smaller than the thoracic duct and drains to where?

the R half of the body superior to the diaphragm

what is lymphedema?

interstitial fluids accumulate from a blockage and the limb gradually becomes swollen and distended

true or false: lymphocytes are WBC’s?

true

what serves as a rapid transport system for lymphocytes moving from one site to another?

the bloodstream

what are the three classes of lymphocytes?

t-cells, b-cells and nk cells

what is t-cells functions?

recognize and attack infected cells and foreign invaders

what is the function of cytotoxic t cells?

directly attack foreign cells or virus-infected body cells

what is the function of helper t cells?

help activate other immune cells

what are regulatory/suppressor t cells?

has both T and B cells, help establish and control the sensitivity of the immune response

what is b-cell functions?

produce antibodies/immunoglobulins, bind to antigens to make it a antigen-antibody which then leads to destruction

what is the function of NK cells?

provide innate (nonspecific) immune can kill infected cells and tumors

where can you find NK cells?

found in blood and lymphatic tissue

where is nk cells developed?

bone marrow

what is immune sureveillance?

constantly monitoring of peripheral tissue to find pathogens, infected cells and cancerous cells

whats the pathway of a lymphocytes?

lymphocytes enter the tissue, wonder through, enter the blood vessels or lymphatic vessels, transport to another site

what does lymphopoiesis mean?

lymphocyte production/development

hemopoietic stem cells have two fates what are they?

fate 1: stay in red bone marrow and generate B and NK cells

fate 2": migrate to the thymus and produce T cells

what are lymphoid tissue?

loose connective tissue dominated by lymphocytes

lymphoid nodules are what?

lymphocytes that are densely packed in an area of areolar tissue

what is the germinal center?

a pale central region that contains dividing lymphocytes

what are mucosa-associated lymphoid tissue or MALT?

specialized lymphatic tissue found in the mucous membrane designed to defend the body from foreign proteins and bacteria

example of MALT

tonsils or appendix

if pathogens do become established in a lymphoid nodule, what response would happen?

inflammatory response

what is an example of lymphoid organ?

lymph nodes, thymus and spleen

afferent lymphatics do what?

deliver lymph to lymph nodes

efferent lymphatics do what?

carry lymph towards the venous system

true or false: the lymph nodes do not filter and remove antigens before it reaches the venous system

false, they do

where does the thymus sit?

in the mediastinum, posterior to the sternum

what is thymosin?

a hormone that stimulates lymphocyte stem cell division and t cell development

what contains the largest collection of lymphoid tissue in the body?

the spleen

function of the spleen

same as lymph nodes but filters blood instead of lymph. ALSO stores recycled iron from RBC’s

define innate (nonspecific) immunity

they DO NOT distinguish between different threats. the response is the SAME regardless of the type of invader. these defense are NOT present at birth

name the seven nonspecific defenses

physical barriers, phagocytes, immune surveillance, interferons, complement, inflammation and fevers

a nickname for phagocytes

“first line”, they attack and remove microorganisms before lymphocytes arrive

what is perforin for?

it is a protein that kills the abnormal cell

if an abnormal cell contains an antigen, who would notice it first?

nk cells, they are respond quicker than t and b cells and slow the infection down

what happens with immunological escape?

cancer cell avoid detection by the nk cells

mast cells release what?

histamine and heparin

what is consider a fever?

99F or higher

what organ is consider the body’s thermostat

hypothalamus

what are pyrogens?

they can reset your thermostat and rise your body’s temperature

how can fevers be benefical?

increase the rate of metabolism, cells move faster and reactions proceed more quickly.

fevers over what temperature can be damaging CNS problems like nausea, disorientation, hallucination and/or convulsion

104F

what meds do you give vs NOT give for a fever?

GIVE acetaminophen or ibuprofen NEVER given aspirin

what does adaptive (specific) defense do?

highly targeted defense system that eliminates specific pathogens and tumor cells

T cells provide a defense against abnormal cells and pathogens inside living cells. this process is called

cell-mediatd immunity or cellular immunity

B cells provide defense against antigens and pathogens in body fluids. this process is called

antibody-mediated immunity or humoral immunity

true or false: adaptive (specific) defense is at birth

false, it is not at birth. it develops only when you have become exposed to a specific antigen

naturally acquired active immunity occurs through

natural exposure to a pathogen leading the body to develop antibodies and memory cells

artifically acquired active immunity is achieved by

through vaccination where the body is exposed to a weakened or inactive form of pathogen to stimulate an immune response

passive immunity is produced by

transferring antibodies to a person from some other source

naturally acquired passive immunity is like

when a baby receives antibodies from the mother before birth or in early stages of infancy

artifically acquired passive immunity is like

when a person receives antibodies to fight infection or prevent disease after exposure

adaptive immunity has four general properties, name them

specificity, versatility, memory and tolerance

t cells are activate by exposure to an

antigen

what is class 1 of MHC protein?

MHC protein acts like a red flag that in effect tells the immune system “hey, im abnormal cell, kill me” then the t cells kill it

what is class 2 of MHC protein?

MHC protein are found in the membrane of lymphocytes and antigen-presenting cells (APC)

APC’s are specialized for what?

activating t-cells to attack foreign cells and foreign protein