Unit I - Immune System (Part 1) Flashcards
innate immunity
body’s first line of defense to prevent entry of pathogens; present at birth
2 basic systems of innate immunity
- skin/mucosal barriers
2. inflammatory response
acquired immunity
body’s immune system to recognize and inactivate foreign substances without injury to other host tissue
- occurs after exposure to a foreign substance after birth
ex) breast feeding, infections
innate immunity also utilizes
natural killer (NK) lymphocytes
function of natural killer (NK) lymphocytes
surveillance
recognize abnormal cells and kills them
secrete performs and Granenzymes
factors that activate natural killer (NK) lymphocytes
cytokines, FcR molecule for Fc antibodies, FcR receptor (see pg 12)
cells for defense - foreign invaders
T and B lymphocytes
passive immunity
acquired by receiving antibodies from another person
ex) breast feeding and vaccines
* quick/effective but temporary
active immunity
resistance that occurs as a result of contact with the foreign body itself
ex) infection
* slow onset, but long term
3 steps of the immune response
- recognition
- elimination
- resolution
any foreign body is referred to as an
antigen (high molecular weight, usually a protein)
Haptens
act as antigens, but smaller molecular weight that binds to a large protein carrier
antigens are determined by their
major histocompatibility complex (MHC) - genetic cell marker (in humans located on 6th chromosome)
MHC determines
epitopes - surface antigens
- located on cell surface
- recognized as “foreign”
- allows immune recognition
antigenic recognition: Dissemination (2 routes)
- lymphatic system
2. blood vascular system
lymphatic system process
- antigen is taken to lymph nodes and sequestered
- stimulate “naive” lymphocytes –> release cytokine called transfer factor (TF), –> effector lymphocytes produced –> sensitized memory lymphocytes produced, immune response initiated
Phase 2 (elimination) 2 components
- cell mediated immunity response
2. humoral immunity response
cell mediated response works from ___ and the humeral response works from ____
T-lymphocytes that are “thymic educated”
B-lymphocytes
cell mediated response pathway
antigen reacts with the CD4 helper T lymphocytes, which are activated and release lymphokines. these activate CD8 (cytotoxic) lymphocytes, which become macrophages and release perforins, which cause the antigen to break down
humeral mediated pathway
antigen reacts with B-lymph and CD4 helper T lymphocytes are activated and release lymphokines. B-lymph forms plasma cells, which produce antibodies, activated immune complement system (soluble mediator), terminates in formation of Membrane Attack Complex, which forms transmembrane channels
immune complement system function - goal 1
forms membrane attack complex (MAC) - forms transmembrane channels that disrupts the cell membrane
lysis (destruction) of the foreign body
immune complement system function - goal 2
opsonization of the antigen - complement fragments and antibodies coat the antigen; antigen phagocytized by macrophages
order of anitbody formation
- IgM, IgG, IgA
antibodies
proteins produced by plasma cells to combat a specific foreign agent
the proteins are called
immunoglobulins
IgG
80% of antibodies in circulating fluids, most abundant
IgM
usually first immunoglobulin to be produced, may be an IgG precursor
IgA
attached to mucosal surfaces
IgE
attached to mast cells, mediates allergies, reaction to parasites
*strongest immune reactions
IgD
- activates young B cells sequestered in the spleen
- usually used with IgM
L chains
- depend on amino acid sequence, but are not considered in classifying the antibody
kappa - 65%
lambda - 35%
Myelodysplastic syndrome
- bone marrow failure
- not making platelets or WBCs
- prone to infection and internal bleeding
- pre leukemia
L chains may appear in the urine as
Bence Jones Protein (BJP) in multiple myeloma
myeloproliferative diseases
- too many plasma cells
- blood too sticky, too viscous
multiple myeloma
- malignant cancer of bone marrow
- over production of plasma B cells, immunoglobulins
- blood hyper viscosity (stains the heart)
- sometimes characterized by acronym CRAB
CRAB
C = blood calcium (elevated) R = renal failure A = anemia B = bone lesions
Waldenstrom’s macroglobulenemia
(same as multiple myeloma but no bone destruction)
- B cells and IgM are overproduced
- grows in lymph nodes
- males 50+, may show monoclonal peak
Waldenstrom’s macroglobulenemia treatment
- plasmapheresis
- progressive, 6.5 years survival
