Transcript t-LYMPHOCYTES

THE LYMPHATIC
SYSTEM
OBJECTIVES
Describe the major functions and structures of
the lymphatic system
List the primary lymphatic structures
Recognize, define, spell, and pronounce the
the major terms related to the system
Discuss and compare the differences in the
immune system
LYMPHATIC SYSTEM
STRUCTURE & FUNCTION
Substances that cannot enter or return
through the capillary walls, including excess
fluid and protein molecules are returned to
the blood as Lymph
Lymph: is a specialized fluid formed in the
tissue spaces that is transported by way of
specialized lymphatic vessels
Cervical Nodes
Mammary Plexus
L. Subclavian
Axillary Nodes
R. Lymphatic Duct
Thoracic Duct
Cubital Nodes
LYMPHATIC
SYSTEM
Iliac Nodes
Inguinal Nodes
Popliteal Nodes
HOW LYMPH IS FORMED
Blood plasma filters out of the capillaries
into microscopic places between
tissues and cells
This process takes place because of the
pressure generated by the pumping action
of the heart
LYMPHATIC
DRAINAGE
OF THE
BREAST
INTERSTITIAL FLUID
Plasma that flows out of the capillaries of the
circulator system
Much of this fluid goes back into the blood
by the same route it came out - - capillary
membrane
LYMPH VESSELS
Capillaries: thin-walled tubes that carry lymph
fluid from the tissues to the larger lymphatic
vessels
Have valves that prevent the backward flow of
fluid and lymph (Toward thoracic cavity)
Right lymphatic duct and thoracic duct empty
lymph into veins in the upper thoracic region
LYMPHATIC
SYSTEM
CAPILLARY
BED
LYMPH VESSELS Cont.
Lacteals: specialized lymph capillaries located
in the villi of the small intestine
-- Fats and fat-soluble vitamins are absorbed
and carried to the bloodstream
LYMPH NODES
Small bean-shaped structures located in lymph
vessels that provide a site for production of
lymphocytes
Filter lymph to remove harmful substances such
as bacteria, viruses, and malignant cells
L
Y
M
P
H
N
O
D
E
SPLEEN
Saclike mass of lymphatic tissue located in the
left upper quadrant of the abdomen, just inferior
(below) the diaphragm and posterior (behind)
stomach
Filters microorganisms
and foreign matter
from blood
Removes and destroys
Worn-out blood cells
-- hemolytic
Forms lymphocytes
and monocytes
SPLEEN
THYMUS GLAND
Lymphoid tissue found in the mediastinum
Critical role in the body’s immunity mechanics
Completes most of its work in early childhood
Produce T-lymphocytes which play a critical
role in the function of the immune system
TONSILS
Masses of lymphatic tissue that
form a protective ring around
the nose and upper throat
TONSIL LOCATIONS
Adenoids: nasopharynx
Palatines: portion of throat
visible through the mouth
Lingual: base of the tongue
TONSILS
VERIFORM APPENDIX
Lymphatic tissue that hangs from
the lower portion of the cecum of
the large intestine
PEYER’S PATCHES
Small areas of lymphatic tissue
found in the walls of the small
intestine
APPENDIX
PEYER’S
PATCH
THE IMMUNE SYSTEM
Function: protects the body from harmful
substances including:
-- Pathogens (disease-producing)
-- Allergens (substances producing allergic
reactions)
-- Toxins (poisons)
-- Malignant cells
IMMUNITY
• State of being resistant or not susceptible to
a specific disease
IMMUNE SYSTEM CELLS
Primary cells of the immune system include:
PHAGOCYTES
-- Neutrophils
-- Monocytes
-- Macrophages
LYMPHOCYTES
-- t-LYMPHOCYTES
-- b-LYMPHOCYTES
IMMUNITY
Antigen: any substance such as a virus,
bacterium, or toxin that the body regards
as foreign.
Antibody: a disease-fighting protein created
by the immune system in response to the
presence of that specific antigen
Immune reaction: also know as antigen-antibody
reaction. Binding foreign antigens to antibodies to
form antigen-antibody complexes
NONSPECIFIC IMMUNITY
Maintained by mechanisms that attack any irritant
or abnormal substance that threatens the internal
environment
Barriers include: skin, mucous membranes, tears
Inflammatory response: nonspecific responses
that occurs in the body such as heat, redness,
swelling, and pain
SPECIFIC IMMUNITY
- Specific protection against certain types of
invaders
- Involves Memory, ability to respond to certain
particular harmful substances
INBORN IMMUNITY
•Inherited immunity to certain diseases.
•Common to the human race.
ACQUIRED ACTIVE IMMUNITY
• Obtained by development of antibodies during
attack of an infectious disease
ACQUIRED PASSIVE IMMUNITY
• Passed from mother to fetus before birth.
• Immediately after birth, additional immunity is
passed from mother to child through breast milk
ARTIFICIAL IMMUNITY
• Also known as immunization
• Immunity that was acquired through vaccines
-----
Chickenpox
Hepatitis B
Smallpox
Pertussis
• May be active or passive
-----
Mumps
Measles
Meningitis
Typhoid
IMMUNE SYSTEM MOLECULES
Functions because of adequate amounts of highly
specialized protein molecules and unique cells
Made up of antibodies and complements
ANTIBODIES
Protein compounds that are normally present in
the body
Able to combine with a specific compound called
an antigen
Promote and enhance phagocytosis
Humoral
-First bind to a specific antigen
-Forms antigen-antibody complex
-Neutralize the toxin
-May agglutinate the enemy cells
-Macrophages “eat” them up.
COMPLIMENTS
Group of at least 14 proteins normally present in
an inactive state in blood
Activated by exposure of complement-binding
sites on antibodies
The result is an antigen-antibody complex
The sequence of events is called compliment
fixation
COMPLIMENT FIXATION
Antigens that are molecules on an antigenic or
foreign cells surface combine with antibody
molecules
Change the shape of the molecule just enough to
expose two previously hidden regions called the
compliment-binding sites
Exposure initiates a series of events that kill the
cell on whose surface they take place
COMPLIMENT FIXATION
Kills invading cells of various types
Drills hole in the plasma membrane
Sodium rapidly infuses the cell
Cell literally bursts
COMPLIMENT FIXATION
IMMUNE SYSTEM CELLS
Primary cells of the immune system include:
PHAGOCYTES
-- Neutrophils
-- Monocytes
-- Macrophages
LYMPHOCYTES
-- t-LYMPHOCYTES
-- b-LYMPHOCYTES
Phagocytes
• Formed in bone marrow
• Perform phagocytosis
• Monocytes/Neutrophils are most
important!!!
Phagocytes
• Migrate into blood and tissues
• In tissues, monocytes develop
into macrophages
Macrophages
• Some macrophages wander through tissue and
“eat” invaders.
• Some stay permanent in organs.
Kupffers Cells- are located in the liver
Dust Cells- are located in small air sacs in lungs
Macrophages
Specialized antibodies help macrophages
function effectively
CAN ALSO BE FOUND IN SPLEEN, LYMPH NODES
LINING OF THORACIC AND ABDOMINAL CAVITIES
Lymphocytes
• Most numerous immune system cells
• Ultimately responsible for antibody production
• Scattered throughout the body’s lymph tissue
• Act like “Gestapo”
B- Cells
and T- Cells
Function of B Cells
Humoral Immunity- resistance to disease
organisms produced by actions of antibodies.
(circulating immunity)
B-CELLS
Known as a B-lymphocyte
-- Designed to make one specific antibody
against a specific antigen
-- Very effective against viruses, and
bacteria circulating in the blood
When confronted with this type of antigen, B
cells transformed into plasma cells
PLASMA CELLS
• Produce and secrete antibodies coded to
match the antigen and secrete the antibodies
coded to match the antigen.
• This match enables the body to destroy the
antigen in the antigen-antibody response
Plasma Cells
-Secrete copious amounts of antibodies
- Live only a few days
- Circulate throughout the body
- Antibody factories
Memory Cells
-Memory cells secrete antibodies
(not immediately)
- Remain in reserve until contacted by the
same antigen
-Transform to plasma cells
T-CELLS
• Also known as T-Lymphocytes
-- Small circulating lymphocytes
-- Matured in the Thymus by exposure to
thymosin
Primary function is to coordinate immune
defense and kill invading organisms on contact
T- Cells
-Cell mediated immunity
-Kill invading cells directly
-Coordinate immune defenses and kill
invading organisms on contact
-Release a lethal poison of a bound cell.
INTERFERON
• Produced by the T-cells
• Proteins released by cells when invaded by
a virus
• Causes noninfected cells to form an antiviral
protein that slows or stops viral multiplication
QUESTIONS
THE END