10 Lymphatic System Flashcards
lymphatics aka
lymph vessel
Lymphatics function
- help maintain the body’s fluid balance
- absorb fats from the digestive tract
- provide immune defense agains microorganisms and disease
lymph aka
lymphatic fluid
a collection of the extra fluid that drains from cells and tissues in your body and isn’t reabsorbed into your capillaries
lymph/
lymphatic fluid
lymph/
lymphatic fluid contains
proteins
minerals
fats
damaged cells
cancer cells
germs
Lymph nodes are kidney-shaped, about 1 cm long, and surrounded by a fibrous capsule _ that extend inward to divide the node into a number of compartments
trabeculae
lymph nodes functions
- remove foreign material - bacteria, tumor cells from lymphatic stream
- provide place where lymphocytes that function in the immune response can be activated
a soft organ located in the left side of the
abdominal cavity, just beneath the diaphragm, that
curls around the anterolateral aspect of the
stomach
Spleen
Spleen functions
- filters and cleanses blood of bacteria, viruses, and other debris.
- provides a site for lymphocyte proliferation and immune surveillance
- destroy worn-out red blood cells and return some of their breakdown products to the liver
organ primarily
responsible for
the production
and maturation
of immune cells
Thymus
small masses of lymphoid tissue deep to the
mucosa surrounding the pharynx
Tonsils
Their job is to trap and remove bacteria or other
foreign pathogens entering the throat
Tonsils
Resembles like tonsils
Peyer’s Patch and Appendix
Peyer’s patches, the appendix, and the tonsils are
part of the collection of small lymphoid tissues
referred to as _
mucosa-associated lymphoid tissue
(MALT)
acts as a sentinel to protect the upper respiratory
and digestive tracts from the constant attacks of
foreign matter entering those cavities
Peyer’s Patch and Appendix
2 defense mechanisms of immune system
innate (nonspecific) defense mechanisms
adaptive (specific) defense mechanisms
Innate defense mechanisms
1st line of defense
- skin
- mucous membranes
- secretions of skin and mucous membranes
Innate defense mechanisms
2nd line of defense
- phagocytic cells
- natural killer cells
- antimicrobial proteins
- the inflammatory response
- fever
Adaptive defense mechanisms
3rd line of defense
- lymphocytes
- antibodies
- macrophages and other antigen-presenting cells
unique group of aggressive lymphocytes that can
lyse (burst) and kill cancer cells, virus infected body
cells, or any nonspecific targets
Natural Killer Cells
Natural Killer Cells attack the target cell’s membrane and release
lytic chemicals called _, which pokes holes in the membrane, and _ (enzymes), which
degrade target cell contents
perforin
granzymes
NK cells also release powerful _
chemicals
inflammatory
a nonspecific response that is triggered whenever
body tissues are injured
Inflammatory Response
four most common cardinal signs of acute
inflammation
- redness,
- heat,
- pain,
- swelling (edema)
A phagocyte, such as a _,
engulfs a foreign particle by the process of
phagocytosis
macrophage or neutrophil
Phagocytes have this flowing _ that bind to the particle
and then pull it inside, forming a phagocytic vesicle.
cytoplasmic extensions
Phagocytes
The vesicle then fuses with a _, where
enzymes digest its contents
lysosome
refers to a group of at least 20 plasma proteins
that circulate in the blood in an inactive state, much
like inactive clotting proteins
Antimicrobial Proteins: Complement
However, when complement becomes attached, or
fixed, to foreign cells such as bacteria, fungi, or
mismatched red blood cells, it is _ and becomes a major factor in the fight against foreign cells
activated
complement initiates
opsonization
any of several related
proteins that are produced by
the body’s cells as a
defensive response to viruses
Antimicrobial Proteins: Interferon
They are important
modulators of the immune
response
Antimicrobial Proteins: Interferon
it is an antimicrobial protein that can also combat
bacterial and parasitic
infections, inhibit cell division,
and promote or impede the
differentiation of cells
Interferons
abnormally high body temperature, is a systemic
response to invading microorganisms
fever
Normally the thermostat is set at approximately
37°C (98.6°F), but it can be reset upward in response to _ (chemicals secreted by white
blood cells and macrophages exposed to foreign
cells or substances in the body)
pyrogens
Adaptive Immune System
a functional system that recognizes foreign molecules called _ and acts to inactivate or
destroy them
antigens
3 Aspects/ Features of Adaptive Immunity
- antigen specific
- systemic
- memory
Aspects of Adaptive Immunity
it recognizes and acts against
particular pathogens or foreign substances
antigen specific
Aspects of Adaptive Immunity
immunity is not restricted to the initial
infection site
systemic
Aspects of Adaptive Immunity
it recognizes and mounts even
stronger, faster attacks on previously encountered
pathogens.
memory
humoral immunity aka
antibody mediated immunity
as it is facilitated by B-cells
A defense provided
by antibodies
(immune proteins)
present in the body’s
“humors,” or fluids
humoral immunity
Cellular Immunity
Cell-mediated immunity because the protective factor is _ (lymphocytes)
living cells
Cellular Immunity
The cellular arm also has _—virus-infected cells, cancer cells, and cells of foreign
grafts
cellular targets
Cellular Immunity
The lymphocytes act against such targets either
directly, by lysing the foreign cells, or indirectly, by _ that enhance the inflammatory
response or activate other immune cells
releasing chemicals
any substance capable of provoking an
immune response
Antigen
An almost limitless variety of substances can
act as antigens, including virtually all foreign
_, _, many large
_, and some _
proteins
nucleic acids
carbohydrates
lipids
Like all blood cells, lymphocytes originate from
_ in red bone marrow.
hemocytoblasts
The immature (called naive) lymphocytes released
from the marrow are essentially _
identical
Whether a given lymphocyte matures into a B cell
or a T cell depends on where in the body it becomes _
immunocompetent
constitute the cell-mediated arm of the
adaptive defenses and do not make antibodies
T - lymphocytes
T cells
can recognize and eliminate specific
virus-infected or tumor cells
T - lymphocytes
T cells arise from lymphocytes that migrate to the _
thymus
T cells undergo a maturation process lasting _,
directed by thymic hormones (thymosin and others)
2 to 3 days
produce antibodies and
oversee humoral immunity
B – lymphocytes or B cells
B cells develop immunocompetence in bone marrow,
but less is known about the factors that regulate _
B cell maturation
After they become immunocompetent, both T cells
and B cells migrate to the _
(and loose connective tissues), where their
encounters with antigens will occur
lymph nodes and spleen
when the lymphocytes bind with recognized
_, they complete their differentiation from
naive cells into fully mature T cells and B cells
antigens
Mature lymphocytes, especially _, circulate
continuously through the body
T cells
Lymphocytes become immunocompetent before
meeting the antigens they may later attack.
Thus, it is our _, not antigens, that determine what foreign substances our immune system will be able to recognize and resist
genes
Antigen-Presenting Cells
engulf antigens and then present _ of
them, like _, on their own surfaces, where
they can be recognized by T cells
fragments
signal flags
major types of cells acting as APCs
- dendritic cells (in connective tissues, epidermis)
- macrophages (lymphoid organs)
- B lymphocytes
Humoral Immune Response
B lymphocyte is stimulated to complete its
development when antigens bind to its _
surface
receptors
Humoral Immune Response
This binding event sensitizes, or activates, the
lymphocyte to “switch on” and undergo _
clonal
selection
Humoral Immune Response
The process in which the b lymphocyte begins to grow and then multiplies rapidly to form an army of cells exactly like itself and bearing the same antigen-specific receptors
clonal selection for humoral immune response
naturally acquired during bacterial and viral
infections, during which we may develop the signs
and symptoms of the disease and suffer a little (or
a lot)
Active Immunity
Active Immunity is _ acquired when we receive _
artificially
vaccines
Active Immunity
Vaccines: (1) spare us most of the _ (and discomfort) of the disease that
would otherwise occur during the primary response
signs and
symptoms
Active Immunity
Vaccines: (2) the _ are still able to stimulate
antibody production and promote immunological
memory
weakened antigens
Active Immunity
a phenomenon in which a population
of people are generally protected because most of a
given population is immune to a disease or infection
Herd immunity
refers to the process of providing IgG antibodies to
protect against infection; it gives immediate, but
short-lived protection—several weeks to 3 or 4 months at most
Passive Immunity
Passive immunity is acquired by a fetus
when it receives maternal antibodies
Natural Passive immunity
Passive immunity is acquired when a
person receives antibodies contained in antisera or
gamma globulin
Artificial Passive immunity
are proteins made in laboratories that act like
proteins called antibodies in our bodies
Monoclonal antibodies (moAbs or mAbs)
The word “monoclonal” refers to the fact that the
antibodies created in the laboratory are _
clones
also referred to as
immunoglobulins constitute the
gamma globulin part of
blood proteins
Antibodies
Antibodies are soluble
proteins secreted by _ in response to an
antigen, and they are
capable of binding
specifically with that antigen
activated B cells or by their plasma-cell offspring
Antibodies inactivate antigens in a number of ways—by _
- complement fixation,
- neutralization,
- agglutination,
- opsonization,
- precipitation
occurs when antibodies bind to
specific sites (usually at or close to the site where a
cell would bind) on bacterial exotoxins (toxic
proteins secreted by bacteria) or on viruses that can
cause cell injury
Neutralization
is an immune process which uses
opsonins to tag foreign pathogens for elimination by
phagocytes
Opsonization
formation of clumps of cells or inert
particles
Agglutination
it is a T cell that specialized
in killing virus-infected,
cancer, or
foreign graft
cells directly
Cytotoxic T
cells
T cells that act as the _ of
the adaptive immune response
“directors” or “managers”
Once T cells activated, they circulate through the _,
recruiting other cells to fight the invaders
body
T helper cells release cytokine to:
(1) stimulating cytotoxic T cells and B cells to grow
and divide;
(2) attracting other types of protective white blood
cells, such as neutrophils, into the area; and
(3) enhancing the ability of macrophages to engulf
and destroy microorganisms.
release chemicals that suppress the activity of both
T and B cells
T regulatory cells
Regulatory T cells are vital for _ the immune response after an antigen has been successfully inactivated or destroyed.
winding down and
stopping
Regulatory T cells help prevent _
immune system activity, which often harms healthy
tissues
uncontrolled or unnecessary
Cells involved in Immunity
lymphocyte that resides in the lymph nodes, spleen, or other lymphoid tissues, where it is induced to replicate by antigen-binding and helper T cell interactions, its progeny (clone members) form plasma cells and memory cells
B cell
Cells involved in Immunity
antibody-producing “machine”, produces huge numbers of the same antibody (immunoglobulin); specialized B cell clone descendant
Plasma cell
Cells involved in Immunity
A T cell that binds with a specific antigen presented by an APC; it stimulates the production of other immune cells (cytotoxic T cells and B cells) to help fight the invader, acts both directly and indirectly by releasing cytokines
Helper T cell
Cells involved in Immunity
Activity enhanced by helper T cells; its specialty is killing cells with intracellular antigen (like viruses, some bacteria); as well as body cells that have become cancerous; involved in graft rejection
cytotoxic T cell
Cells involved in Immunity
slows or stops the activity of B and T cells once the infection (or attack by foreign cells) has been conquered; thought to be important in preventing autoimmune diseases
regulatory T cell
Cells involved in Immunity
descendant of an activated B cell or T cell; generated during both primary and secondary immune responses; may exist in the body for years thereafter, enabling it to respond quickly and efficiently to subsequent infections of meetings with the same antigen
memory cell
Cells involved in Immunity
any of sevenral cells types (macrophages, dendritic cell, B cell) that engulfs and digests antigens that it encounters and presents parts of them on its plasma membrane for recognition by T cells bearing receptors for the same antige; this function, antigen presentation, is essential for normal cell-mediated responses. Macrophages and dendritic cells also release chemicals (cytokines) that activate many other immune cells
antigen-presenting cell APC
Organ Transplant and Rejection
are tissue grafts harvested from a
different animal species, such as a porcine (pig)
heart valve transplanted into a human
Xenografts
Organ Transplant and Rejection
are tissue grafts taken from a person
other than an identical twin.
Allografts
Organ Transplant and Rejection
are tissue grafts donated by a genetically
identical person, the only example being an
identical twin
Isografts
Organ Transplant and Rejection
are tissue grafts transplanted from one
site to another in the same person.
Autografts
Drugs that prevent your immune system from
attacking healthy cells and tissues by mistake
Immunosuppressive Therapy
corticosteroids
antiproliferative drugs
immunosuppressor drugs
Immunosuppressive Theraphy
to suppress inflammation
corticosteroids
Many of these drugs kill rapidly dividing cells (such as activated lymphocytes), and all of them have severe side effects
Immunosuppressive Theraphy
to prevent division of
immune cells
antiproliferative drugs
Many of these drugs kill rapidly dividing cells (such as activated lymphocytes), and all of them have severe side effects
