2. INTRODUCTION
Immune and
lymphatic systems
work to protect body
from pathogens that
can produce disease
Without these
systems, you would
not survive for long
3. THE DEFENSE ZONE
If a group of
pathogens try to
enter body, they
must first get past
barriers, such as
intact skin and
secretions of
mucous
membranes
4. PHYSICAL BARRIERS
Anything that
prevents invaders
from getting inside
your body prevents
infection
Physical barriers
act as first line of
defense; located in
areas most likely to
be invaded
Skin and mucous membranes
of eyes, digestive,
respiratory, reproductive
systems
5. PHYSICAL BARRIERS
Anything that
prevents invaders
from getting inside
your body prevents
infection
Physical barriers
act as first line of
defense; located in
areas most likely to
be invaded
Skin and mucous membranes
of eyes, digestive,
respiratory, reproductive
systems
6. THE DEFENSE ZONE
If pathogen does
get into body, it is
recognized as
not belonging
Weapons in the
form of
specialized cells
are engaged by
immune and
lymphatic
systems to fend
off the pathogens
7. THE DEFENSE ZONE
Weapons include
specialized cells and
powerful chemicals of
immune and lymphatic
systems
Chemicals stimulate
inflammatory and clean
up responses
Again, this is accomplished
by combined and integrated
efforts of immune and
lymphatic systems
8. THE LYMPHATIC SYSTEM
Both the transport system
and barracks of immune
system
Works closely with
cardiovascular system
10. STRUCTURES OF THE
LYMPHATIC SYSTEM
Smallest pipes of lymphatic system called
lymph capillaries; run parallel to blood
capillaries
11. STRUCTURES OF THE
LYMPHATIC SYSTEM
Lymph capillaries form network
between cells of connective tissues, but
unlike blood capillaries, are open ended
12. THE LYMPHATIC SYSTEM
Proteins and fluids are lost from cardiovascular
capillaries and enter interstitial space.
13. THE LYMPHATIC SYSTEM
Once this fluid enters
lymph capillaries, it is
known as lymphatic fluid
(lymph)
Lymph: straw-colored,
clear fluid; primary
component is water
14. THE LYMPHATIC SYSTEM
Lymph capillaries empty
into lymphatic vessels,
similar to veins including
valves; body movement
and contraction of
smooth muscles propels
lymph through system
16. LYMPH NODES
Large vessels empty into lymph nodes, ranging in size
from pinhead to an olive
Lymph nodes: filters placed all along pathways or
vessels of lymphatic system
17. FIGURE 14-2
THE LYMPH NODE STRUCTURE
Small, encapsulated bodies
divided into sections
Consist of sections of
lymphatic tissue containing
WBCs known as
lymphocytes
18. LYMPH NODES
Lymphatic tissue surrounded by lymphatic
sinuses filled with lymph fluid
Filter and destroy pathogens using WBCs
19. LYMPH NODES IN THE BODY
Concentrated in
cervical, axillary,
inguinal, pelvic,
abdominal,
thoracic, and
supra trochlear
areas
Adenoids and
tonsils also part
of lymph system
21. COLLECTING DUCTS
Lumbar, intestinal,
and intercostal
trunks empty into
thoracic duct the
largest lymph
vessel; more than
two-thirds of
lymphatic system
drains into this duct
Lymphatic trunks empty into
one of two collecting ducts
23. CIRCULATION OF
LYMPHATIC FLUID
Lymphatic fluid flows in
only one direction: from
body tissues and organs
to heart
Blood to tissue
Tissue to lymphatic
capillaries
Lymphatic capillaries to
lymphatic vessels
24. CIRCULATION OF
LYMPHATIC FLUID
1.
Lymphatic capillaries
to lymph nodes
2.
Lymph nodes to
lymphatic vessels
3.
Lymphatic vessels to
lymphatic trunks
4.
Lymphatic trunks to
collecting ducts
5.
Collecting ducts to
subclavian veins and
then back to the blood
25. LYMPH ORGANS
Spleen
Spongy saclike mass of
lymphatic tissue in upper left
quadrant of abdomen
Structurally similar to lymph
nodes but instead of lymphatic
sinuses has blood sinuses
Surrounding blood sinuses are
islands of white pulp containing
lymphocytes and islands of
red pulp containing both RBCs
and WBCs
26. LYMPH ORGANS
Spleen
Functions to remove and
destroy old, damaged,
or fragile RBCs
Also filters pathogens
from bloodstream and
destroys them like lymph
node
Not vital organ; can be
surgically removed;
removal in children can
severely compromise
immunity, but has lesser
effect on adults
27. LYMPH ORGANS
Thymus
Soft organ located
between aortic arch and
sternum
Very large in children
because it must fend off
new infections
Gets smaller; continues to
have some activity in
adults as immune system
fully matures in its ability
to fight infection
28. LYMPH ORGANS
Thymus
Site of mature
type of WBC
called a T
lymphocyte
(made in the
bone marrow)
31. THE IMMUNE SYSTEM
Comprised of cells,
chemicals, and barriers
that protect body from
invasion by pathogens
Some processes active,
some passive, some
inborn, and others
change with experience
32. ANTIGENS-SELF OR
FOREIGN?
Molecules on outer
surface of cell membrane
that identify them as friend
or foe
Each living thing has
unique cell surface
antigens, allowing immune
system to distinguish
between cells that are
naturally yours and cells
that are not
33. ANTIGENS
Ability called self-
recognition and non-selfrecognition; is heart of
how immune system
functions
Well-functioning immune
system ignores self
antigens and attacks
non-self antigens
34. ANTIBODIES
Proteins the body makes
that bind to antigens,
eventually destroying
them
One of most potent
weapons of immune system
Called into action when
foreign antigen invades
the body
35. INNATE VERSUS ADAPTIVE
IMMUNITY
Innate (natural)
immunity
First line of defense
against invasion
Body's inborn ability to
fight infection
Not affected by
environment
Permanent
36. INNATE VERSUS ADAPTIVE
IMMUNITY
Innate (natural)
immunity
Prevents invasion,
or if pathogens do
get inside, takes
steps to stop
spread of
infection
37. INNATE IMMUNITY-RECOGNIZES A
FOREIGN INVADER
The body’s first line of
defense recognizes
that invader is present
but can’t identify it
specifically
Like setting off a metal
detector but not knowing
exactly what the item is
that did it
38. INNATE VERSUS ADAPTIVE
IMMUNITY
Innate (natural)
immunity
Cannot improve with
experience
Because it does not
recognize specific
pathogens, it cannot
"remember" an
infection that body has
encountered before
“ I CAN’T REMEMBER”
39. INNATE VERSUS ADAPTIVE
IMMUNITY
Crude mechanism
for defending body
Indiscriminately
killing pathogens
and healthy tissue
alike
Take that, invader
I’m one
of you!!
40. INNATE VERSUS ADAPTIVE
IMMUNITY
Adaptive (acquired) immunity
Backs up innate immunity, specifically targeting invaders and
sparing healthy tissue as much as possible
Remembers invaders from previous encounters and prepares
for future invasion, improving response with experience by learning
and changing
41. INNATE VERSUS ADAPTIVE
IMMUNITY
Innate and adaptive immunity work together
Innate immunity prepares way for adaptive immunity,
weakening pathogens and stimulating components of
adaptive immunity
44. CELLS OF THE BODY
White blood cells
(WBC or leukocytes)
are cells responsible
for defending body
against invaders
Red blood cells
responsible for
carrying oxygen
throughout body
Platelets
responsible for
blood's ability to clot
45. CELLS OF THE BODY
Leukocytes
Form in bone
marrow; move to
other parts of body to
grow and mature
Not released into
bloodstream unless
infection present
Various types of
white blood cells
required to protect
body in varying
circumstances
46. LYMPHOCYTES
T (for Thymus) and B
(for bone marrow)
cells
Form in bone marrow;
some move to other
parts of body to grow
and mature
T cells go to the
thymus to mature
B cells stay, develop
and mature in the bone
marrow
47. LYMPHOCYTES-T AND B CELLS
Specific T cells called T
helper cells stimulate
“killer T cells” which
directly bind to antigen
or pathogen and destroy
it
T helper cells also
stimulate B cells to
make B plasma cells
which produce
antibodies and make B
memory cells
48. LYMPHOCYTES-T AND B CELLS
Both formed in the
marrow both cells
stimulated by the
presence of a foreign
antigen
B cells develop into
plasma cells which
forms antibodies to
specific antigen and
memory cells which
“remember” it later
50. CHEMICALS TO PROTECT BODY
FROM INVADERS
Found in body; assist
in destroying and
neutralizing invaders
Cytokines:
Involved in both innate
and adaptive immunity
51. CYTOKINES
Cytokines are proteins
produced by damaged
tissues and WBCs that
stimulate immune
response in variety of
ways:
Increasing
inflammation
Stimulating
lymphocytes
Enhancing
phagocytosis
52. INTERFERONS
Cytokine produced
by cells that have
been infected by
virus
Binds to neighboring,
uninfected cells and
stimulates them to
produce chemicals
that may protect
these cells from
viruses
54. INFLAMMATION
Deliberate action of body
in response to tissue
damage, whether
mechanical or pathological
injury
Response helps to wall
off infected area to
prevent further spread and
allow battle to focus at site
55. INFLAMMATION
When tissue is
damaged, cells
send out
chemicals such as
histamine, an
inflammation
modulator
56. INFLAMMATION
These chemicals
attract WBCs to site,
increase
permeability of
capillaries, and
cause local
vasodilitation; extra
fluid causes
swelling
More blood comes to
site, causing heat
57. INFLAMMATION
WBCs destroy pathogens
and clean away dead cells
Increase in fluid and cells
coming to area increases
pressure and creates pain
Innate immune mechanism,
but plays important part in
adaptive immunity
59. FEVER
During infection, immune
system releases cytokines
that promote
inflammation and immune
responses
One of cytokine targets in
brain is HYPOTHALAMUS
responsible for setting and
maintaining body
temperature
60. FEVER
Effect of cytokine is
elevated temperature
set point, or fever
Rise in body temperature
is deliberate attempt by
immune system to
destroy pathogens
61. INNATE IMMUNITY-BARRIERS
First, pathogens
must get past
physical and
chemical
barriers; most
pathogens kept
out by these
barriers
Tears, saliva, urine, mucous
secretions and sweat contain
chemical barriers
65. INNATE IMMUNITY
Pathogens are under
attack from:
Phagocytosis
Noxious chemicals
Membrane rupture
Clumping
Alteration to molecular
structure
66. INNATE IMMUNITY
Chemicals have
specifically signaled
hypothalamus to
raise body
temperature and
you run a fever
67. INNATE IMMUNITY
Remember: This is crude
warfare, with innate
immunity destroying
anything non-self
Desperate attempt to
defeat invaders,
sometimes killing
uninfected cells…
All leading to activation
of adaptive immunity
68. INNATE IMMUNITY
When phagocytic
cells ingest
pathogens, they
display foreign
antigen on cell
membrane,
essential for
activation of B and T
cells
69. ADAPTIVE IMMUNITY
Fights specific
pathogens; has
memory, "learns"
from experience,
recognizes specific
pathogens
73. ADAPTIVE IMMUNITY IS THEN
ACQUIRED
Exposure is either
Exposure is either
Acquired
Acquired
immunity
immunity
occurs as the
occurs as the
body
body
“adapts” to
“adapts” to
the
the
environment
environment
to which it is
to which it is
exposed
exposed
“passive”
“passive”
(nonspecific
(nonspecific
antigen exposure)
antigen exposure)
or “active”
or “active”
(specific targeted
(specific targeted
exposure)
exposure)
Exposure is
Exposure is
“natural” or
“natural” or
“artificial”
“artificial”
(created by
(created by
humans)
humans)
79. THE BIG PICTURE
Army of pathogens wants to
invade body; first must get past
body's barriers
If invader gets inside body, series
of weapons stimulated by nonself-antigen
Cells (neutrophils, macrophages,
and basophils) stimulated
Chemicals (cytokines) released
that stimulate inflammation and
phagocytosis
80. THE BIG PICTURE
Macrophages and other
cells which have
ingested some of
invaders move to
lymphatic system and
search lymph nodes,
looking for T and B cells
that will recognize
intruder
81. THE BIG PICTURE
Helper T cells activate
and cause
proliferation of B
cells and cytotoxic
T cells, as well as
releasing chemicals to
further stimulate
phagocytosis and
inflammation
T cells (green) infected with HIV (red)
82. THE BIG PICTURE
Cytotoxic T cells activated
and proliferate
B cells produce
antibodies that destroy
invaders and further
stimulate immune response
Cytotoxic T cells destroy
invaders directly and
release chemicals that
further stimulate immune
response
83. THE BIG PICTURE
Immune response, both innate and adaptive, will
continue to be stimulated until feedback loop stopped,
at least in part by regulatory T cells
Memory B cells and T cells stored in lymph nodes for
later use if another army of same types of pathogens
invade
84. THE BIG PICTURE
Macrophages and other phagocytic cells will clean up
debris left by “warfare” waged by immune system and
body will return to normal
86. AUTO IMMUNE DISEASE
Read article “Auto Immune Diseases”
Read article “Auto Immune Diseases”
It is believed that
viruses can
incorporate genetic
material into human
cells that changes it’s
“ID CARD”, so that it
is then identified as
foreign, triggering an
antigen-antibody
reaction
88. CHAP 14 TAKE HOME EXAM
Complete Worksheet No. 1
Complete Worksheet No. 1
and the Labeling Activity 1 and 3
and the Labeling Activity 1 and 3
for credit (46 points) ..
for credit (46 points)
Questions #24 and #25 are
Questions #24 and #25 are
EXTRA CREDIT
EXTRA CREDIT
(worth 7 points)
(worth 7 points)
One ESSAY Question on the
One ESSAY Question on the
Lymphatic System will appear on
Lymphatic System will appear on
your FINAL EXAM
your FINAL EXAM