Immune system #1 Flashcards
inherited defense mechanisms
innate, nonspecific immunity
adaptive or specific immune response is a funciton of
lymphoctyes
How does the innate immne system distinguish between self and invading pathogens?
recognizing pathogen associated molecular patterns (PAMPS)
Common PAMPs
lipopolysaccharide found in gram negative bacteria and peptidoglycan in gram positive
Receptor proteins that recognize pamps
pathogen recognition receptors
group of pathogen recognition receptors that responds to LPS from bacteria
toll like receptors
Cell attractant molecules that recruit other immune cells
chemokines
cell growth and regulatory molecules
cytokines
receptors that activate the transcription of genes that promote defenses like autophagy
NOD like receptors
What system promotes the formation of antigen antibody complexes
complement system
Complement proteins are part of the _____ immune system
innate
Local inflammation produced when tissue damage causes necrosis exposes the immune system to
DAMPS danger associated molecular patterns (or damage)
T/F apoptosis generally does not provoke inflammation
true
another name for neutrophils
polymorphonuclear cells
cells of the mononuclear phagocyte system
monocytes, macrophages, dendritic cells
microglia of the brain are an example of
organ specific phagocytes
phagocytic cells of the liver
kupffer cells
immoble phagocytes within organs
fixed phagocytes
What organs sterilize the blood
liver and spleen
Chemokines promote
chemotaxis
What cells are the first to arrive at the site of an infection
neutrophils
the ability of WBS to squeeze through gaps of endothelial cells
extravasation or diapedesis
What signals “eat me” to macrophages?
phosphatidylserine
What coordinates skeletal muscle shivering for thermoregulation?
thermoregulatory control center in the hypothalamus
What can a fall in plasma iron cause?
inhibit bacterial activity
Polypeptides that produce nonspecific short acting resistance to viral infection
interferons
What is produced by almost all cells in the body to respond to microbial infections?
alpha and beta interferons
The secretion of what polypeptide is part of the immunological defense against infection and cancer?
gamma interferon
what becomes plasma cells?
b cell lymphocytes
Areas of a molecule that can stimulate the production of or combine with antibodies
antigenic determinant sites (epitopes)
small organic molecules that are not antigenic but can be if they bind to proteins
haptens
Penicilin can bind to your platelets and cause what
drug induced thrombocytopenia purpura
2 examples of immunoassays
blood typing and pregnancy test
Where are lymphocytes produced?
bone marrow, thymus, spleen and lymph nodes
Lymphocytes that seed the thymus
T lymphocytes (T cells)
Where does the B come from in B cells?
bursa of Fabricius in chickens
B cells provide what kind of immunity
humoral or anitibody mediated immunity
What cells directly attack host cells
T Cells
When is the thymus most active
in infancy
What provides cell mediated immunity
T cells
What does humoral immunity protect from
extracellular bacteria and viruses, bacterial toxins, snake venom
What does cell mediated immunity protect from?
intracellular bacteria (like TB) intracellular viruses (parasites) fungi, protozoans, transplants, cancer cells
Where is the repoplation of T cells usually performed in adulthood?
secondary lymphoid tissue rather than thymus
Secondary lymphoid organ in the intestines
peyer’s patches
antigen presenting cells
dendrites, macrophages, b cells
Why do lymphocytes travel continuously?
to increase likelihood that a specific lymphocytes will encounter a specific antigen
cells found mostly in the skin, bronchioles and intestinal mucous and contain heparin
mast cells
Mast cells are best known for their production of what?
histamine
When histamine binds to its receptors, what happens
bronchiolar constriction and vasodilation
Where are histamine and heparin stored?
granules of mast cells
what chemokine recruits neutrophils to the site of an infection?
tumor necrosis factor
Extracellular fibers taht trap invading pathogens
Neutrophil extracellular traps (NETS)
What is opsonization?
antibodies acting as bridge between the microbe and the phagocytic cell
Examples of opsonates
antibodies and complement
redness and warmth in inflammation is due to
histamine stimulated vasodilation (mast cells)
What produces the pain in inflammation
prostaglandin E2 (PGE2)
How does aspirin inhibit pain and fever?
It inhibits cyclooxygenase enzymes that produce prostaglandins
Most common endogenous pyrogen?
interleukin 1
Where are memory and plasma cells created?
the germinal center of secondary lymphoid organs
What class of plasma proteins contains the antibodies?
gamma globulins
Another name for antibodies
gamma globulins, immunogloblins (Ig)
What re most of the antibodies circulating in the plasma?
IgG
What antibodies are involved in allergic reactions?
IgE
What is the stalk of the antibody and what is the top of the Y?
crystallizable fragment (Fc) and antigen binding fragment (Fab)
3 components of complement proteins
- Recognition (c1) 2. Activation (C4, C2, C3) 3. Attack (C5-C9)
The classic pathway of ________ is initiated by binding of IgG antibodies to their cell surface receptors
complement dependent cytotoxicity
C5-C9 is inserted to the bacterial cell membrane to form a
membrane attack complex (large pore that lyses the cell)
What kills the cell in the classic pathway?
the complement proteins
3 functions of complement fragments being liberated into surrounding fluid
chemotaxis, opsonization, release of histamine
How do Killer T cells kill their victim cells?
cell mediated destruction (membrane to membrane)
What surface molecule identifies cytotoxic t cells?
CD8
What do killer t cells secrete to kill their target?
perforins and granzymes
What enzyme is involved in apoptosis and is activated by granzymes?
caspases
What kind of lymphocytes protect us from TB?
cytoxic t cells (CMI)
Name of bacili that causes TB?
myobacterium tuberculosis
Virus with genetic material in its rna
retrovirus
Drugs that inhibit enzyme reverse transcriptase
antiretroviral therapy
What is targeted by human immunodeficiency virus
helper T cells, especially in gastrointestinal mucous
What surface molecule defines helper T cells
CD4
How do helper T cells aid immune response of B and T lymphocytes
secretion of lymphokines
Positive result of a TB test would be indicated by
hard red area
What provides the brake on immune response?
Regulatory (suppressor) T lymphocytes
What do regulatory T lymphocytes gard against?
autoimmune disease and allergy
Function of interleukin 1
endogenous pyrogen, promote fever
Function of interleukin 2
development and function of helper, killer and regulatory T lymphocytes
Symptoms of sepsis
high fever, rapid pulse, hypotension, hypoxemia, oliguria, acidosis
Powerful instigator of septic shock
endotoxin
B lymphoctyes can recognize antigens that are ______ but t lymphocytes can only recognize _____
proteins or carbs, proteins
How do the T cell membrane receptors differ from antibody receptors on B cells?
T cell receptors cannot bind to free antigens, they must be presented on the membrane of antigen presenting cells!
chief antigen presenting cells
dendritic, followed by macrophages and b cells
dendritic cells and macrophages are derived from
monocytes
Where are antigen presenting cells especially concentrated?
skin, intestinal mucosa, lungs
Dendritic cells of the epidermis
Langerhans cells
How do dendritic cells interact with the correct T lymphocytes?
they migrate through lymphatic vessels and secrete chemokines to attract them
Activated T cells divide to first produce ____ and then _____
effector T cells, memory T cells
All tissue cells except mature RBC are genetically marked with
histocompatibility antigens
What kind of cells are used for tissue typing to reduce chance of transplant rejection?
WBC
Another name for histocompatibility antigens?
human leukocyte antigens, Major histocompatibility complex molecules
What chromosome are MHC genes located on?
6
What class of MHC molecules are produced by all cells (except RBC) and what class is produced by only antigen presenting cells?
Class 1, Class 2
What coreceptor is associated with class 1 MHC molecules and what coreceptor is associated with class 2 MHC molecules?
CD8, CD4
Antigen presenting cells have ______ that cause them to engulf viruses and migrate to secondary lymphatic organs
Pathogen recognition receptors (PPRs)
After migrating to secondary lymphatic organs with their engulfed viral cells, antigen presenting cells present the viral polypeptides along with ______ to _____
MHC class 2 molecules, helper T lymphocytes
Killer T cells can only destroy infected cless if
they display the foreign antigen together with class 1 MHC molecules
Interaction between what helps provide long term humoral immunity and ability of vaccines to evoke active immunity?
helper T cells and B cells
After infection has been cleared, what happens to activated T lymphocytes?
they are destroyed
What triggers apoptosis in lymphocytes
finding of FAS to FAS ligand
What do immunological privileged sites in the body contain to protect them from autoimmune destruction?
FAS ligand, triggers apoptosis of any T lymphocytes that may enter
What other cells produce FAS ligand?
some tumor cells
What drugs suppress the immune system
glucocorticoid drugs
glucocorticoids enhance cytokines secreted from _____ cells compared to ___ which promotes a shift from_____ immunity to _____
TH2, TH1, cell mediated to humoral
Born without antibody mediated immunity and cell mediate immunity
Severe combined immnodeficiency disease (SCID or bubble boy disease)
What is missing in bubble boy disease?
stem cells of WBC lack enzyme adenosine deaminase
How did bubble boy die?
bone marrow transplant contained mononucleosis virus and gave him B cell lymphoma
What neurotransmitter is affected by bird flu (also called what?)
dopamine, H5N1
What cranial nerves involved with the travel of H5N1?
vagus and olfactory
What indicated that the woman in the vital signs article had lupus?
butterfly mark, pain in joints, hair loss, and positive antinuclear antibody test
What drugs are used to combat inflammation in lupus?
cortisone and antimalarial drugs
Full name for lupus
systemic lupus erythematosus
