Chapter 18 - Assessment of Immune Function
- Immunity is state of responsiveness
- Defense: body 1ghts against pathogens
- Homeostasis: keeps cells unchanged
- Surveillance: recognized cells as foreign
- Immunity refers to the body’s ability to resist infection and disease
- First, immune system cells need to distinguish self from nonself
- Immune function:
- Changes during a person’s life:
- Nutritional status
- Environmental condition
- Drugs
- Presence of disease
- Age
- Antigens
- Substances that induce the production of antibodies
- They are a normal part of the person
- Specify the tissue type of person
- Anatomy of the Immune system
- Lymph nodes and lymphatic system
- Lymphatic system is a network of vessels that transports excess interstitial Ruid that has
not been reabsorbed (lymph Ruid) back to the bloodstream, helping to maintain Ruid
balance
- Lymph nodes are located super1cial and deep that house macrophages,
lymphocytes, and monocytes that actively 1lter and phagocytize microorganisms
and other invading particles
- Thymus: where T-cell development takes place, located near the heart
- Bone Marrow:
- Consists of red (active) marrow and yellow (inactive marrow)
- This is where B and T lymphocyte formation and di?erentiation of B and
T cells occur
- B cells stay within the bone marrow to mature
- T cells migrate to the thymus to mature and become active as regulatory T cells
(suppressor T cells) or e?ector T cells (helper T cells and cytotoxic T
cells)
- Spleen: serves as a blood 1lter
- Tonsils: function as traps to protect against bacterial and viruses that are inhaled
- Adenoids: defend against inhaled bacteria and viruses
, - Peyer’s Patches: known as intestinal immune sensors and defend against pathogens that
gain entry to the intestinal tract
- Leukocytes:
- White blood cells that are formed in the bone marrow and lymph tissue
- Leukocytes are mobile units traveling through the bloodstream to defend the body
against infection.
- There are 5 types: neutrophils, monocytes, eosinophils, basophils and lymphocytes ( B and
T cells)
- They are classi1ed further into granulocytes or agranulocytes depending on their function
- Granulocytes have granules in the cytoplasm and release histamines and other
substances to defend the body against foreign materials by increasing capillary
permeability through vasodilation and mediating the inRammatory response.
- Neutrophils, basophils, and eosinophils are phagocytic granulocytes as they engulf
bacteria and debris
- Neutrophils: phagocytes of early inRammation that destroys bacteria
- Eosinophils: phagocytes that destroy allergens and combat parasitic infections
- Basophils: release heparin as an anticoagulant and histamine during the early
inRammatory response
- Agranulocytes (without granules in the cytoplasm) include monocytes and lymphocytes
- Monocytes: in the bloodstream are part of the adaptive (acquired) immune response,
presenting pathogens to T cells for destruction. (monica is selfish and will turn the
pathogens in to the T cells)
- Macrophages: are the monocytes of the tissue, they are phagocytes and initiators of the
inRammatory response that digest and destroy, or phagocytize, microorganisms and other
debris. They also activate helper T cells (macrophages need HELPERS to destroy the
debris) by secreting signaling proteins, called cytokines and presenting processed antigens for
destruction by T cells.
- Lymphocytes (a type of WBC)
- Active in both humoral and cell mediated immune responses
- Enter the bloodstream through the lymphatic system
- B Lymphocytes: 10-20%
- B cells are the cells involved in humoral immune response
- Subset of lymphocytes that mature in the bone marrow and produce antibodies or
immunoglobulins
, - Antibodies bind with speci1c antigens marking them for destruction by other parts of
the immune system.
- Once B cells are exposed to a speci1c antigen for the 1rst time they proliferate
and diIerentiate into plasma cells and memory cells.
- Plasma cells secrete antibodies after the 1rst exposure to the antigen
- Memory cells restimulated by the same antigen, mount speci1c antigen-antibody
response, sometimes long after the initial exposure
- Can function independently but B cells need help from T lymphocytes
- Immunoglobulins (Igs) that B cells produce include 5 classes: ADEGM
- IgA: dominant Ig found in secretions such as breast milk, tears, and sweat
- IgD: assists in activation of B cells
- IgE: associated with allergic reactions and parasitic infections
- IgG: most abundant, eIective against bacteria, viruses, and other toxins
- IgM: is the initial antibody produced after an infection
- T lymphocytes
- Participants in cellular mediated immune responses
- T cell activation (done by monica) occurs when macrophages (aka monocytes)
present the T cell with a phagocytized antigen
- Their main function includes the elimination of cells infected by pathogens,
continued activation of the inRammatory response against persistent infections
and regulation of innate and adaptive immune responses.
- T cells include:
- Cytotoxic T cells: Respond to foreign cells
- Suppressor T cells: activated by the helper T cells when the
immune response is no longer needed
- Helper T cells: important cells in both adaptive and innate immunity
response by activating macrophages.
- They augment both humoral and cellular immunity (INVOLVED
BOTH IN T CELL AND B CELL) through the activation of B cells
to produce antibodies
- They also activate cytotoxic T cells and natural killer cells
(HELPER T CELLS ACTIVATE EVERYONE BUT
SUPPRESSORS)
- Natural Killer Cells: targets virus infected and tumor cells, as the individual
age the number of NK cells increase to help control infections in the elderly and
is important for successful aging.
- Cytokines
- Small proteins that act to regulate immune response
- They are produced in response to speci1c antigens by cells of the acquired immune system
, - Small protein hormones
- Act as “messengers” - tell speci1c cells how and when to respond
- Control many inRammatory and immune responses
- Controlled by interactions with other systems, especially the nervous system
- Interleukins: are the largest group of cytokines, responsible for the general enhancement
or suppression of inRammation and stimulation of leukocyte production and maturation.
- Interferon: proteins that protect against viral infections and tumor growth, do not destroy
but prevent it from spreading
- ****interferons and interleukins are used clinically to stimulate hematopoiesis, bone
marrow and to treat malignancies.
- Tumor necrosis factor alpha: enhances inRammation and is involved in the regulation
and production of immune cells
- Types of Immunity
- Innate (natural) - provides 1rst and second lines
- Provides barriers and an inRammatory response that is immediate, nonspecific,
and without memory as 1rst and second lines of defense against threats that are
foreign
- Neutrophil and monocytes are the main cells involved
- The 1st step is to identify if it is a self or non self antigen, this is usually done by
a dendritic cell that will present it on its surface and allow for recognition by the
immune cells. (HLA system)
- Physical, biochemical, and mechanical barriers that oIer surface protection to
prevent the invasion of microbes THIS IS FIRST LINE: (coughing, sneezing,
vomiting, urinating working with biochemical surface secretions such as tears, saliva,
and earwax)
- When the barriers are breached the inRammatory response is initiated THIS
IS SECOND LINE
- 1st and second line are non specific, responding the same way for any invasion
- InRammatory Response: 2nd life of defense
- Acute cellular injury
- Occurs due to tissue damage such as a break in the skin that
introduces microorganisms
- The goal of the inRammation is to prevent and/or limit infection and further
damage to the involved area, remove debris and prepare the area of injury
for healing
- Vasodilation with increased capillary permeability- increased blood Row to
the area brings leukocytes to engulf the organisms in the tissue
- Lastly there is promotion of fibrous scarring- seen by the
swelling, heat, redness and pain
- Adaptive (acquired)
- Immunity is state of responsiveness
- Defense: body 1ghts against pathogens
- Homeostasis: keeps cells unchanged
- Surveillance: recognized cells as foreign
- Immunity refers to the body’s ability to resist infection and disease
- First, immune system cells need to distinguish self from nonself
- Immune function:
- Changes during a person’s life:
- Nutritional status
- Environmental condition
- Drugs
- Presence of disease
- Age
- Antigens
- Substances that induce the production of antibodies
- They are a normal part of the person
- Specify the tissue type of person
- Anatomy of the Immune system
- Lymph nodes and lymphatic system
- Lymphatic system is a network of vessels that transports excess interstitial Ruid that has
not been reabsorbed (lymph Ruid) back to the bloodstream, helping to maintain Ruid
balance
- Lymph nodes are located super1cial and deep that house macrophages,
lymphocytes, and monocytes that actively 1lter and phagocytize microorganisms
and other invading particles
- Thymus: where T-cell development takes place, located near the heart
- Bone Marrow:
- Consists of red (active) marrow and yellow (inactive marrow)
- This is where B and T lymphocyte formation and di?erentiation of B and
T cells occur
- B cells stay within the bone marrow to mature
- T cells migrate to the thymus to mature and become active as regulatory T cells
(suppressor T cells) or e?ector T cells (helper T cells and cytotoxic T
cells)
- Spleen: serves as a blood 1lter
- Tonsils: function as traps to protect against bacterial and viruses that are inhaled
- Adenoids: defend against inhaled bacteria and viruses
, - Peyer’s Patches: known as intestinal immune sensors and defend against pathogens that
gain entry to the intestinal tract
- Leukocytes:
- White blood cells that are formed in the bone marrow and lymph tissue
- Leukocytes are mobile units traveling through the bloodstream to defend the body
against infection.
- There are 5 types: neutrophils, monocytes, eosinophils, basophils and lymphocytes ( B and
T cells)
- They are classi1ed further into granulocytes or agranulocytes depending on their function
- Granulocytes have granules in the cytoplasm and release histamines and other
substances to defend the body against foreign materials by increasing capillary
permeability through vasodilation and mediating the inRammatory response.
- Neutrophils, basophils, and eosinophils are phagocytic granulocytes as they engulf
bacteria and debris
- Neutrophils: phagocytes of early inRammation that destroys bacteria
- Eosinophils: phagocytes that destroy allergens and combat parasitic infections
- Basophils: release heparin as an anticoagulant and histamine during the early
inRammatory response
- Agranulocytes (without granules in the cytoplasm) include monocytes and lymphocytes
- Monocytes: in the bloodstream are part of the adaptive (acquired) immune response,
presenting pathogens to T cells for destruction. (monica is selfish and will turn the
pathogens in to the T cells)
- Macrophages: are the monocytes of the tissue, they are phagocytes and initiators of the
inRammatory response that digest and destroy, or phagocytize, microorganisms and other
debris. They also activate helper T cells (macrophages need HELPERS to destroy the
debris) by secreting signaling proteins, called cytokines and presenting processed antigens for
destruction by T cells.
- Lymphocytes (a type of WBC)
- Active in both humoral and cell mediated immune responses
- Enter the bloodstream through the lymphatic system
- B Lymphocytes: 10-20%
- B cells are the cells involved in humoral immune response
- Subset of lymphocytes that mature in the bone marrow and produce antibodies or
immunoglobulins
, - Antibodies bind with speci1c antigens marking them for destruction by other parts of
the immune system.
- Once B cells are exposed to a speci1c antigen for the 1rst time they proliferate
and diIerentiate into plasma cells and memory cells.
- Plasma cells secrete antibodies after the 1rst exposure to the antigen
- Memory cells restimulated by the same antigen, mount speci1c antigen-antibody
response, sometimes long after the initial exposure
- Can function independently but B cells need help from T lymphocytes
- Immunoglobulins (Igs) that B cells produce include 5 classes: ADEGM
- IgA: dominant Ig found in secretions such as breast milk, tears, and sweat
- IgD: assists in activation of B cells
- IgE: associated with allergic reactions and parasitic infections
- IgG: most abundant, eIective against bacteria, viruses, and other toxins
- IgM: is the initial antibody produced after an infection
- T lymphocytes
- Participants in cellular mediated immune responses
- T cell activation (done by monica) occurs when macrophages (aka monocytes)
present the T cell with a phagocytized antigen
- Their main function includes the elimination of cells infected by pathogens,
continued activation of the inRammatory response against persistent infections
and regulation of innate and adaptive immune responses.
- T cells include:
- Cytotoxic T cells: Respond to foreign cells
- Suppressor T cells: activated by the helper T cells when the
immune response is no longer needed
- Helper T cells: important cells in both adaptive and innate immunity
response by activating macrophages.
- They augment both humoral and cellular immunity (INVOLVED
BOTH IN T CELL AND B CELL) through the activation of B cells
to produce antibodies
- They also activate cytotoxic T cells and natural killer cells
(HELPER T CELLS ACTIVATE EVERYONE BUT
SUPPRESSORS)
- Natural Killer Cells: targets virus infected and tumor cells, as the individual
age the number of NK cells increase to help control infections in the elderly and
is important for successful aging.
- Cytokines
- Small proteins that act to regulate immune response
- They are produced in response to speci1c antigens by cells of the acquired immune system
, - Small protein hormones
- Act as “messengers” - tell speci1c cells how and when to respond
- Control many inRammatory and immune responses
- Controlled by interactions with other systems, especially the nervous system
- Interleukins: are the largest group of cytokines, responsible for the general enhancement
or suppression of inRammation and stimulation of leukocyte production and maturation.
- Interferon: proteins that protect against viral infections and tumor growth, do not destroy
but prevent it from spreading
- ****interferons and interleukins are used clinically to stimulate hematopoiesis, bone
marrow and to treat malignancies.
- Tumor necrosis factor alpha: enhances inRammation and is involved in the regulation
and production of immune cells
- Types of Immunity
- Innate (natural) - provides 1rst and second lines
- Provides barriers and an inRammatory response that is immediate, nonspecific,
and without memory as 1rst and second lines of defense against threats that are
foreign
- Neutrophil and monocytes are the main cells involved
- The 1st step is to identify if it is a self or non self antigen, this is usually done by
a dendritic cell that will present it on its surface and allow for recognition by the
immune cells. (HLA system)
- Physical, biochemical, and mechanical barriers that oIer surface protection to
prevent the invasion of microbes THIS IS FIRST LINE: (coughing, sneezing,
vomiting, urinating working with biochemical surface secretions such as tears, saliva,
and earwax)
- When the barriers are breached the inRammatory response is initiated THIS
IS SECOND LINE
- 1st and second line are non specific, responding the same way for any invasion
- InRammatory Response: 2nd life of defense
- Acute cellular injury
- Occurs due to tissue damage such as a break in the skin that
introduces microorganisms
- The goal of the inRammation is to prevent and/or limit infection and further
damage to the involved area, remove debris and prepare the area of injury
for healing
- Vasodilation with increased capillary permeability- increased blood Row to
the area brings leukocytes to engulf the organisms in the tissue
- Lastly there is promotion of fibrous scarring- seen by the
swelling, heat, redness and pain
- Adaptive (acquired)
