Ch. 22 Lymphatic and Immune System
Spleen (on LT side of the abdomen) is where lymphocytes check
Blood for bacteria, viruses and debris
Formation and flow of lymph
Blood plasma -> Interstitial fluid -> Lymph capillaries -> Lymph vessels -> Lymph nodes for filtration -> Lymph trunks -> Lymphatic ducts -> Subclavian veins
Fluid and plasma must be returned to keep ___/___ maintained and to prevent edema
Blood volume/blood pressure
Homeostatic imbalance of lymph nodes- Swollen lymph nodes
Buboes- overwhelmed lymph nodes, large number of bacteria and viruses
___ are broken down into small fragments that associate with MHC molecules
Antigenic proteins
Complement fixation and types
Attachment of protein to foreign body, activates the protein - Membrane Attack Complexes -Opsonization
Lymphoma
Benign or malignant tumor of lymphoid tissue - Non-Hodgkin Lymphoma - Hodgkin disease
Plasma cell (lymphocyte)
Descendant of B cell that produces and secretes antibodies.
Memory B cell (lymphocyte)
Descendant of B cell that remains after immune response and is ready to respond rapidly and forcefully should the same antigen enter body in future.
B cell (lymphocytes)
Differentiates into antibody producing plasma cell.
Passive humoral immunity
Differs in Ab source and degree of protection •Ab obtained from an immune human or animal donor •B cells are not activated, no memory, protection ends when Ab degraded
Pathogen
Disease causing microorganism
Thymus gland (lymphoid organ) peak function
During childhood (large in the infant and after puberty is large replaced by adipose and areolar connective tissue)
Immunogenicity
Stimulate proliferation of specific lymphocytes and Antibodies •Antigenic determinants(epitopes)- immunogenic parts of an antigen, can have multiple types •Plastics have few determinants and are used for artificial implants
Self
Not seen as a threat
House the immune cells
Organs and tissues
Remaining fluid from hydrostatic pressure becomes
Part of interstitial fluid between cells
Immune cells
Phagocytic cells and lymphocytes
B lymphocytes
Plasma and memory cells
Memory T cells (or memory cytotoxic T cells)
Remain to provide quick action at next exposure to same antigen
Memory T cell (lymphocytes)
Remains in lymphatic tissue and recognizes original invading antigens, even years after first encounter.
Splenectomy
Removal of spleen when hemorrhaging - Less common today, found to heal itself and regenerate in children
Immunology
Study of the immune system (specific defense)
The ___ is then inserted into the membrane of a body cell (antigen presentation)
antigen-MHC complex
Which of the following conditions is a tropical disease where lymphatics are clogged with parasitic roundworms resulting in edema of enormous proportions? a. Hodgekins disease b. Elephantiasis c. Buboes d. Non-Hodgkin lymphoma
b. Elephantiasis
True or False: High fever is beneficial and not dangerous. a. True b. False
b. False
Which of the following is a primary lymphatic organ/tissue? a. Spleen b. Red bone marrow c. Lymph nodes d. Peyer's patches
b. Red bone marrow
Where can the Peyer's patches be found? a. Kidneys b. Small intestine c. Pancreas d. Throat
b. Small intestine
Which of the following destroys and stores breakdown products of old red blood cells, acts as a blood reservoir, and stores platelets? a. Thymus b. Spleen c. Red bone marrow d. Lymph nodes
b. Spleen
Which of the following is the site of T-Cell maturation? a. Lymph nodes b. Thymus c. Spleen d. Tonsils
b. Thymus
Which of the following drains roughly 75% of all of the body's lymph? a. Left lymphatic duct b. Brachiocephalic trunk c. Thoracic duct d. Right lymphatic duct
c. Thoracic duct
Breast milk provides an infant with with antibodies helping to protect the infant. This type of immunity is a. artificial active immunity b. artificial passive immunity c. natural passive immunity d. natural active immunity
c. natural passive immunity
Which of the following can be found within our body's first line of defense? a. antibodies b. complement c. skin and mucous membranes d. phagocytes
c. skin and mucous membranes
Antigens are substances recognized as
foreign that provoke immune responses (ANTIbody GENerating)
Membrane Attack Complexes
formed by complement fixation, proteins form holes in cell membrane for lysis
Complete antigens functional properties
immunogenicity and reactivity
Secondary lymphatic organs and tissues
lymph nodes, spleen, lymphatic nodules (tissues)
The body system that carries out immune responses is the
lymphatic system
Lymph nodes are clustered along
lymphatic vessels that filter lymph
Slow flow through node allows
lymphocytes and macrophages to do their job
Lymphatic nodules are
masses of lymphatic tissue that are not surrounded by a capsule
Complement proteins
•20-30 plasma proteins in blood •Amplify inflammatory response, cause cell lysis, promote phagocytosis
5. Fever
•Abnormally high body temp. •Pyrogens- chemicals secreted by WBCs and macrophages, cause body temp. to increase
Physical and chemical barriers of 1st line of defense
•Acidic pH of skin secretions and sebum inhibits bacteria growth •Hydrochloric acid and digestion enzymes of the stomach •Saliva and lacrimal fluid (lysozymes) •Sticky mucus traps pathogens in respiratory and digestive tracts and cilia work to move the substance out
Organs and tissues house the immune cells and are known as
"wastewater treatment system"
Opsonization
(coating of microbe)- causes membranes to become sticky, easier for adherence (phagocytosis)
Homeostatic imbalances: Transplants
- Autograft- tissue graft from one place to another in same person - Isograft- genetically identical tissue donated (twin) - Allograft- tissue taken from non-related person (most common) - Xenograft- tissue taken from another species
Components of the lymphatic system
- Blind lymphatic capillaries - Lymphatic vessels - Lymphatic nodes - Lymphatic trunks - Lymphatic ducts
Disorders- AIDS (Acquired Immunodeficiency Syndrome)
- Caused by human immunodeficiency virus (HIV) transmitted in body fluids •Destroys Helper T cells depressing immune response •Cytotoxic T cells mount initial response but become unresponsive to viral cues •Virus multiplies in lymph nodes
Structure of antibodies
- Consist of 4 polypeptide chains •Differ in structure - Variable and Constant regions
Lymphocytes
- Cytotoxic T cell - Helper T cell - Memory T cell - B cell - Plasma cell - Memory B cell
APC(antigen presenting cells) that engulf antigen and present fragments on their membrane to T cells
- Dendritic (Langerhans) cells in skin - Macrophages - Activated B lymphocytes
Other functions of spleen
- Destroys and stores breakdown products of old RBCs - May produce RBCs in fetus - Act as a blood reservoir, stores platelets (1/3) and monocytes
Lymphatic system functions (3)
- Drain interstitial fluid - Carry out immune responses - Transport dietary fats
Immune system two defense systems
- Innate (nonspecific) system; First and Second line of defense, always ready - Adaptive (specific) system; Third line of defense, must be primed; Attacks particular foreign substances
2 types of antimicrobial chemicals
- Interferon (IFN) proteins - Complement proteins
Homeostatic imbalances: Rejections
- MHC and tissue rejection - Patient receives immunosuppressive therapy •Corticosteroids (suppress inflammation), cytotoxic drugs, radiation therapy, immunosuppressor drugs •Prone to infections
Phagocytes types
- Macrophages- derived from monocytes - Neutrophils- become phagocytic upon encountering foreign substance - Eosinophils- weak phagocytes, defend against parasitic worms
Types of passive humoral immunity
- Natural- fetus gets passive immunity from mother that lasts several months after birth - Artificial- given immune serum •Given after hepatitis exposure •Immune sera after snake bite, botulism, rabies, hepatitis exposure Effects short-lived (2-3 wks)
Types of active humoral immunity
- Naturally acquired during infections - Artificially acquired with vaccines- contain dead or attenuated (weakened) pathogens, prime the system •Spared most of the symptoms of disease •Promotes immunological memory by providing antigenic determinants that are reactive and immunogenic •Hepatitis B, pneumonia, smallpox, polio, tetanus, diphtheria, measles
Immediate Hypersensitivities
- Reaction can be local or systemic - Begins in seconds, lasts ~ ½ hour - No symptoms on first encounter; B cells produce vast amounts of Ab - Second exposure causes basophils to release histamine •Causes runny nose, redness, itching, watery eyes - Inhaled or ingested allergens •inhaled- cause smooth muscle constriction, asthma •ingested- abdominal discomfort •treated with over-the-counter drugs, containing antihistamine
Lymphoid tissue - Tonsils
- Small masses of tissue, ring the throat - Trap foreign pathogens entering throat - Tonsillitis - red and swollen due to excess bacteria
Homeostatic imbalance of lymph nodes- Secondary cancer sites
- Some cancers use lymphatic system to spread - Swollen glands are usually painless making them distinguishable from inflamed glands
Lymph nodes
- Surrounded by CT (connective tissue) capsule - Contain lymphatic nodules made up of B cells - More afferent vessels than efferent vessels - slow flow - All lymph flows through more than one lymph node - Contain reticular fibers that act as a filter
Some of the cells inside of a lymph nodes
- T cells - Dendritic cells - B cells - Macrophages
Lymphoid tissue - Peyer's patches
- Wall of small intestines (ilium) - Prevent foreign substances from entering intestinal wall
Buboes cause and is a *** function
- inflammation and tenderness - Swelling during infection is a trapping function
Plasma cells
-B cell descendant, secrete Ab -Produce much more antibody (Ab) than B cell •Produce 2000 molecules per second •Last 4-5 days
2nd line of defense components (5)
1. Phagocytes 2. NK cells 3. Inflammatory response 4. Antimicrobial chemicals 5. Fever
Which of the following cells requires antigen-presentation to be activated? a. T cells b. B cells c. macrophages d. all of the above
A. T cells
Which of the following filter lymph? a. lymph nodes b. lymphatic vessels c. spleen d. all of the above
A. lymph nodes
Neutralization
Ab binds bacterial exotoxins (secreted toxic chemical) rendering it harmless
Route of flow through a lymph node
Afferent lymphatic vessel -> Subcapsular sinus -> Trabecular sinus -> Medullary sinus -> Efferent lymphatic vessel
Lymph enter through
Afferent lymphatic vessels, flow through node, exits at hilus by efferent lymphatic vessels
Non-Hodgkin's Lymphoma
All cancers of lymphoid tissue except Hodgkins lymphoma, due to lymphocytes, 7th most common cancer, often occurs in young people
For an immune response to occur,
B cells and T cells must recognize that a foreign antigen is present
Antibody-mediated
B cells mature in the bone marrow
Breast milk provides an infant with antibodies helping to protect the infant. This type of immunity is a. natural active immunity b. natural passive immunity c. artificial active immunity d. artificial passive immunity
B. natural passive immunity
Filtered lymph is returned to the blood at the a. right atrium b. pulmonary veins c. subclavian veins d. left atrium
C. subclavian veins
Helper T cells
CD4 cells, director - Release chemicals that recruit other cells to fight (Macrophages, B cells, T cells) - Release cytokines (Stimulates T cell and B cell growth; Attracts other WBCs; Enhances innate defense system)
Cytotoxic (killer) T cells
CD8 cells •Virus, cancer cells, grafts •Insert toxins (perforins) into foreign cell membrane
Lymphatic capillaries which are closed on one end, are located between
Cells of many tissues
Lymphatic capillaries are
Closed on one end
Agglutination
Clumping of foreign cells by cross-linking
Antigens types
Complete or incomplete
Helper T cell (lymphocyte)
Cooperates with B cells to amplify antibody and secretes interleukins, which stimulates proliferation of T cells and B cells. May secrete tumor necrosis factor (T N F), which stimulate inflammatory response.
Precipitation
Cross-linking becomes so large complex settles out of solution
Tropical disease where lymphatics are clogged with parasitic round worms resulting in edema of enormous proportions
Elephantiasis
Sentinel node
First node that receives lymph drainage from a suspected cancerous area, biopsied to determine if cancer has metastasized into lymph tissue
Hydrostatic pressure (BP) in capillary beds forces
Fluid and some plasma proteins out
Vessels transport
Fluids back to the blood
Nonself
Foreign, threat
The immune system
Functional system rather than organ system
•Genetically engineered ___ used to combat Hepatitis C, herpes, and viral infections in organ transplants
IFNs
Variable region forms 5 major classes in order of abundance
IgG, IgA, IgM, IgD, IgE [GAMDE (Go And Make Donuts Early!)]
Primary lymphatic organs are where
Immune cells become immunocompetent - Red bone marrow (B cells) - Thymus (T cells)
Adaptive immunity, third line of defense
Immune response to antigens
Disorders: Autoimmune diseases
Immune system attacks self-antigens, damages own tissue - Multiple Sclerosis- myelin sheaths - Myasthenia gravis- neuromuscular - Grave's disease- thyroid gland - Type I diabetes mellitus- pancreas - Systemic lupus erythematosus (SLE)- kidneys, heart, lungs, skin - Glomerulonephritis- kidneys - Rheumatoid arthritis- joints
There are large clusters of lymph nodes in
Inguinal, axillary, and cervical regions
Leukocytosis
Injured cells produce leukocytosis-inducing factors, causes neutrophil release from bone marrow
Inflammatory response: Injured cells
Injured cells release chemicals •Histamines, kinins, prostaglandins, complement, and cytokines
Cytotoxic T cell (lymphocyte)
Kills host target cell by releasing granzymes that induce apoptosis, perforin that forms channels to cause cytolysis, granulysin that destroys microbes, lymphotoxin that destroys target cell DNA, interferons that attracts macrophages and increases phagocytic activity.
phagocyte mobilization
Leukocytosis -> Margination -> Diapedesis -> Chemotaxis
Lymph vessels pass through lymph nodes and then merge into
Lymph trunks
Lymph capillaries merge to form
Lymphatic vessels which convey lymph into and out of lymph nodes
Lymphatic capillaries merge to form
Lymphatic vessels which have thin walls and many valves
Antigen- Presenting Cells (APCs)
Macrophage Dendritic cell B Cell
*** remove, "filter", foreign material (from lymph)
Macrophages
Hodgkin disease
Malignant lymphoid tissue, malignant B cells, non-painful swollen lymph nodes, genetic and mononucleosis predisposing factors
Flow through node is slow due to
More afferent vessels than efferent
Complement fixation
Most common; activation leads to cell lysis
Secondary lymphatic organs are the sites where
Most immune responses occur
Immunocompetence
Mounting an immune response
Diapedesis
Neutrophils squeeze through capillary wall
Margination
Neutrophils travel to inflamed site, stick to capillary wall
Nonspecific Resistance (Innate Immunity) is present and includes
Present at birth and includes defense mechanisms that provide general protection against invasion by a wide range of pathogens and their toxins
Dendritic cell (APCs)
Processes and presents antigen to T cells and B cells; found in mucous membranes, skin, lymph nodes
B cell (APCs)
Processes and presents antigen to helper T cells.
Macrophage (APCs)
Processing and presentation of foreign antigens to T cells; secretion of interleukins and interferons (induces proliferation of B cells and T cell growth.)
Antigen
Protein (self or foreign) substance, recognized by immune system
Antibody
Protein that tags a foreign substance
Self-antigens
Proteins found on our cells, don't usually activate immune response - Major histocompatibility complex (Human leukocyte antigens) - May be antigenic to other people (transplants)
Interferon (IFN) proteins
Proteins produced by virus-infected cells diffuse to nearby cells to induce synthesis of antiviral proteins - prevent replication
RT lymphatic duct empties into -> Thoracic duct empties into ->
RT subclavian vein LT subclavian vein
Inflammatory response
Response to tissue damage, includes pain, redness, immobility, swelling, and heat (PRISH)
First line of defense
Skin and mucous membranes
Antibodies (aka immunoglobulins- Igs)
Soluble proteins secreted by B cells that bind to antigens
Adaptive immunity has both ___ and ___ and is divided into 2 types
Specificity and memory; Cell-mediated & antibody-mediated
Thymus gland is the site of
T cell maturation
Cell-mediated
T cells mature in the thymus
Lymph trunks merge to form
The thoracic duct or RT lymphatic duct
Thymus gland produces
Thymosin and thymopoietins that function to program lymphocytes (T cells)
Active humoral immunity
When B cells are challenged and produce Ab
Inflammatory response: effects
a)Prevents spread of damage (clotting factors) b)Disposes of cell debris and pathogens •Neutrophils and Monocytes squeeze through blood vessels (diapedesis) to damaged area to clean debris c)Sets stage for repair (fibrin mesh)
Which of the following form "Membrane Attack Complexes"? a. Complement proteins b. Antibodies c. Interferon d. NK cells
a. Complement proteins
Which of the following is NOT one of the classes of immunoglobulins? a. IgS b. IgG c. IgM d. IgE
a. IgS
Which of the following filter lymph? a. Lymph nodes b. Spleen c. All of the available answer options are correct d. Lymphatic vessels
a. Lymph nodes
Which of the following is an example of MALT? a. Tonsils b. Spleen c. Lymph nodes d. Thymus
a. Tonsils
True or False: Lymph flows through several lymph nodes before returning back to the cardiovascular system. a. True b. False
a. True
Adaptive immunity involves
activation of specific lymphocytes that combat a particular pathogen or other foreign substance
Which of the following is the most common type of transplant? a. Xenograft b. Isograft c. Allograft d. Autograft
c. Allograft
Which cells are the major mediators of the humoral immune system? a. Macrophages b. T-cells c. B-cells d. NK cells
c. B-cells
Cytotoxic T cells are often called a. CD1 T-cells b. CD4 T-cells c. CD8 T-cells d. CD2 T-cells
c. CD8 T-cells
Which of the following would be the biggest type of vessel? a. Lymphatic capillaries b. Lymphatic trunks c. Lymphatic ducts d. Lymphatic arteries
c. Lymphatic ducts
PRISH is an acronym that is used to help us remember the signs of inflammation. The "R" in PRISH stands for a. Rugged b. Rich c. Redness d. Rash
c. Redness
Which of the following is NOT an APC? a. Dendritic cells b. B cells c. T cells d. Macrophages
c. T cells
Which of the following is FALSE regarding lymph nodes? a. They contain reticular fibers that act as a filter b. They are surrounded by a connective tissue capsule c. They have more efferent vessels than afferent vessels d. They contain lymphatic nodules made up of B cells
c. They have more efferent vessels than afferent vessels
Lymph flows through several nodes before
cleaning is complete
The innate immune system includes which of the following? a. 1st line of defense b. 2nd line of defense c. 3rd line of defense d. 1st and 2nd lines of defense e. 1st, 2nd, and 3rd line of defense
d. 1st and 2nd lines of defense
Which of the following includes phagocytes, NK cells, and fever as defense mechanisms? a. 4th line of defense b. 1st line of defense c. 3rd line of defense d. 2nd line of defense
d. 2nd line of defense
Which of the following is(are) functions of the lymphatic system? a. Transport dietary fats b. Drain interstitial fluid c. Carry out immune responses d. All of the available answer options are correct
d. All of the available answer options are correct
Which of the following cells destroys virally infected cells using granzymes and perforin? a. CD4 T-cells b. Macrophages c. B-cells d. CD8 T-cells
d. CD8 T-cells
Which of the following is an autoimmune condition that affects the kidneys? a. Myasthnia Gravis b. Multiple Sclerosis c. Grave's Disease d. Glomerulonephritis
d. Glomerulonephritis
Which of the following refers the our "non-specific" immune system that we are born with? a. Cell-mediated immunity b. Adaptive immunity c. Humoral immunity d. Innate immunity
d. Innate immunity
Filtered lymph is returned to the blood at the a. Right atrium b. Left atrium c. Pulmonary veins d. Subclavian veins
d. Subclavian veins
Which of the following cells requires antigen-presentation to be activated? a. B-cells b. All of the available answer options are correct c. Macrophages d. T-cells
d. T-cells
Which of the following is TRUE regarding complete antigens? a. The require a binding protein in order to stimulate an immune response b. Lipids make the strongest complete antigens c. They gain immunogenicity when linked with a self-protein d. They display both immunogenicity and Reactivity
d. They display both immunogenicity and Reactivity
Which of the following is an example of artificially-acquired active immunity? a. Infections b. All of the available answer options are correct c. Anti-venom d. vaccines
d. Vaccines
Adaptive immunity refers to the body's ability to
defend itself against specific invading agents (bacteria, viruses, transplants, self-cells that have mutated)
Lymphatic nodules in the GI, urinary, and reproductive tracts and the respiratory airways are referred to as
mucosa-associated lymphatic tissue (MALT)
Most fluid and plasma proteins forced out by hydrostatic pressure is
reabsorbed at venous end
Reactivity
react with lymphocytes and Antibodies
Lymphocytes are produced in
red bone marrow
The lymphatic system consists of
several structures and organs that contain lymphatic tissue, bone marrow, and a fluid called lymph that flows within lymphatic vessel
2 types of lymphatic ducts
thoracic duct and right lymphatic duct
Lymphatic nodules are scattered
through the lamina propria of mucuous membranes lining the GI, urinary, and reproductive tracts and the respiratory airways
How are lymphocytes activated?
when they encounter foreign antigens
Homeostatic imbalances: Allergies
•Allergies occur when a person is overly reactive to a substance that is well-tolerated by most others •When an allergic reaction occurs, so does tissue damage •There are sub-types of hypersensitivity reactions; based on the allergen and the response
In cell-mediated immunity
•An antigen is recognized and bound •Clonal Selection - A small number of T cells proliferate and differentiate into a clone of effector cells •The antigen is eliminated
Allergen enters blood
•Anaphylactic shock, systemic response •Bee stings, spider bites, penicillin •Epinephrine used to reverse histamine effects
Antibody-Mediated (Humoral) Immune Response: B cells
•Antigen is recognized and bound •Helper T cells co-stimulate the B cell to proliferate and differentiate •B cell grows and multiplies rapidly to form army of identical cells (clones) •Produces Plasma and Memory cells •Antigen is eliminated
Adaptive immunity, 3rd line of defense characteristics
•Antigen specific •Systemic- not restricted to initial infection site •Memory- mounts stronger attacks on previously encountered pathogens
Memory cells
•B cell descendants that aren't plasma cells •Long-lived, fewer made than plasma cells •Responsible for immunological memory for the next time an antigen is encountered
Inflammatory response: Chemical effects
•Blood vessels dilate causing hyperemia- redness and heat •Exudate seeps out of capillaries- fluid with clotting factors and antibodies, swelling and pain •Chemotaxis- attract phagocytes and WBCs
Activity of cytotoxic T cells
•CD8 cell binds to target cell and releases granules with perforins •Perforins insert into membrane forming pores •Granzymes enter pores and degrade cellular contents CD8 cell detaches and hunt
IFN effects
•Cause uninfected cells to produce the enzyme PKR protein that interferes with virus replication •Activate Macrophages and NK cells
phagocytosis 5 stages
•Chemotaxis •Adherence •Ingestion •Digestion •Killing
Immune system functions to protect body
•Direct- cell attack •Indirect- mobilizing chemicals and antibodies
Phagocytes
•Engulf foreign substances •Digest particles with enzymes in lysosomes
Functions of antibodies
•Forms antigen-antibody complex to tag for destruction •Neutralization, agglutination, precipitation, and complement fixation
Disorders- AIDS continued
•HIV multiplies in lymph nodes and can invade brain •Antiviral drugs (AZT) inhibit enzyme HIV needs to multiply •Combination drug therapy postpones drug resistance •Ultimately die from overwhelming infection or cancer
Aging and the immune system results in
•Increased susceptibility to infections and malignancies •Increased production of autoantibodies •Decreased response to vaccines •Decreased immune system function
Disorders: Autoimmune diseases triggers
•Ineffective lymphocyte programming •Self-reactive B or T cells not eliminated, escape
Chemotaxis
•Inflammatory chemicals recruit neutrophils to precise location •Monocytes follow Neutrophils and develop into Macrophages
Mild to moderate fever
•Liver and spleen gather iron and zinc, bacteria need these nutrients to multiply •Increases metabolic rates to speed up repair processes
Secondary humoral response
•More effective, bettered prepared, faster •Ab blood levels peak 2-3 days and at higher levels (titer) than primary response
Inflammatory responses (4)
•Pus •Acute inflammation •Chronic inflammation •Abscesses and Ulcers
Two lines of NON-SPECIFIC defense
•Skin and mucous membranes •Internal defenses
Delayed hypersensitivities
•Slow; begin 1 to 3 days after exposure •Involves cytotoxic and helper T cells •No Antibodies •Cytokines released (instead of histamine) •Corticosteroids used to provide relief •Allergic contact dermatitis •Haptens diffuse through skin •Poison ivy, heavy metals, cosmetic chemicals, tuberculosis tests
Cytotoxic (subacute) hypersensitivities
•Slower onset; •begins 1 - 3 hours after exposure •may last 10 - 15 hours •Mismatched blood transfusion
Incomplete antigens (haptens)
•Small molecules that have reactivity but not immunogenicity •Gain immunogenicity when linked with a self protein, results in allergies
2. Natural killer (NK) cells
•Type of lymphocyte, found in blood and lymph •Lyse and kill a variety of cancer cells and virus-infected cells (not specific) •Release chemicals called perforins that cause the target cell to disintegrate •Secrete chemicals that enhance inflammatory response
High fever
•dangerous due to denaturation- proteins (enzymes) break down
Incomplete antigens structure
•peptides, nucleic acids, hormones, and chemicals Poison Ivy, dander, detergents, cosmetics
Complete antigens structure
•proteins (strongest), carbs, lipids, nucleic acids •Pollen grains and microorganism surfaces have foreign macromolecules