The Lymphatic & Immune
System
MALENA BOOME
LAUREN HELMER
IKER LOPEZ
ANATOMY, PERIOD 3
PRESENTATION DATE: 4/11/13
Introduction
 The lymphatic system is closely associated with the
cardiovascular system. The 3 main functions:
1.
2.
3.
Transports excess fluid to the blood stream
Absorbs fats
Helps defend the body against disease- causing agents.
Major Organs & Lymphatic Pathways
 Major organs: Heart, lungs, intestines, liver, and skin
have lymphatic vessels. The brain, however, has no
lymphatic vessels
 Lymphatic capillaries: microscopic, close-ended
tubes that extend to interstitial spaces
 Lymphatic vessels: thinner walls than those of veins,
possess valves that prevent back flow of lymph
Lymphatic
vessels
transporting
fluid to
interstitial
spaces to the
bloodstream
Location of Major Lymphatic pathways
 Larger lymphatic vessels lead to lymph nodes, then
merge into lymphatic trunks. These trunks lead into
2 collecting ducts: the thoracic duct and the right
lymphatic duct.
Lymph & Tissue Fluid
 Tissue fluid originates from blood plasma
 As the protein concentration of tissue fluid increases,
colloid osmotic pressure increases
 Increasing pressure within interstitial spaces forces
some tissue fluid into lymphatic capillaries, and that
fluid turns into lymph

Lymph: returns protein molecules to the blood stream and
transports foreign particles to lymph nodes
Lymph Nodes
 Subdivided into nodules that contain phagocytes and
macrophages
 Lymph nodes collect along the paths of larger
lymphatic vessels
 Functions:
1.
2.
Filter potentially harmful foreign particles from lymph
Centers for the production of lymphocytes & contain phagocytic
cells
Thymus & Spleen
 Thymus: an organ composed of lymphatic tissue
divided into lobules that shrinks after puberty
1.
Function: lymphocytes leave the thymus and provide
immunity
 Spleen: an organ resembling a large lymph node
that’s subdivided into lobules that contains
macrophages.
1.
Function: The macrophages filter foreign particles and
damaged red blood cells from blood
Body Defenses Against Infection
 The body has innate (nonspecific) and adaptive
(specific) defenses against infection.
 Innate and adaptive defense mechanisms work
together to protect the body against infection.
 Innate defenses respond rapidly, adaptive defenses
which are slower to respond, still begin as well.
Innate Defenses
 Species resistance

A given kind of organism, or species develops a set of diseases that is unique
to it.
 Mechanical Barriers

The skin and mucous membranes lining the passageways of the respiratory,
digestive, urinary, and reproductive systems.
 Chemical Barriers

Enzymes in body fluids provide a chemical barrier to pathogens.
 Fever

Elevated body temperature due to fever offers powerful protection.
 Inflammation

A tissue response to injury or infection, producing localized redness,
swelling, heat, and pain.
 Phagocytosis

Bloods most active phagocytic cells are neutrophils and monocytes.
Adaptive Defenses, or Immunity
 Antigens

Before Birth, body cells inventory “self” proteins and other large
molecules. After inventory, lymphocytes develop receptors that
allow them to differentiate between nonself (foreign) and self
antigens.
 Lymphocyte Origins

Lymphocytes originate in red bone marrow and are released into the
blood before they differentiate.
 Lymphocyte Functions

Some T cells interact with antigen- bearing agents directly, providing
the cellular immune response. T cells secrete cytokines, such as
interleukins, that enhance cellular responses to antigens. B cells
interact with antigen-bearing agents indirectly, providing the
humoral immune response.
Adaptive Defenses, or Immunity (continued).
 T Cells and Cellular Immune Response

T cells are activated when an antigen-presenting cell displays a
foreign antigen. When a macrophage acts as an accessory cell, it
phagocytizes an antigen- bearing agent, digest the agent, and
displays the antigens on its cell membrane in association with
certain MHC proteins.
 B Cells and the Humoral Immune Response

A B cell is activated when it encounters an antigen that fits its
antigen receptors. An activated B cell proliferates, enlarging its
clone. Some activated B cells specialize into antibody- producing
plasma cells. Antibodies react against the antigen- bearing agent
that stimulated their production. An individuals diverse B cells
defend against a very large number of Pathogens.
 Types of Antibodies

Antibodies are soluble proteins called immunoglobulin's.
Types of Antibodies (continued).
 Immunoglobulin G (IgG)

IgG is in plasma and tissue fluids and is particularly effective
against bacteria, viruses, and toxins.
 Immunoglobulin A (IgA)

Commonly found in exocrine gland secretions. It is in breast milk,
tears, nasal fluid, gastric juice, intestinal juice, bile, and urine.
 Immunoglobulin M (IgM)

Develops in the blood plasma in response to contact with certain
antigens in food or bacteria. Types of antibodies that are IgM are –
anti- A and anti-B. Also activates complement.
 Immunoglobulin D (IgD)

Found on the surfaces of most B cells, especially those of infants. It
is important in activating B cells.
 Immunoglobulin E (IgE)

Appears in exocrine secretions along with IgA. It is associated with
allergic reactions.
Adaptive Defenses or Immunity (continued).
 Antibody Actions

Antibodies directly attach to antigens, activate complement or stimulate
local tissue changes that are unfavorable to antigen-bearing agents. Direct
attachment results in agglutination, precipitation, or neutralization.
Activated proteins of complement attract phagocytes, alter cells so that they
become more susceptible to phagocytosis, and rupture foreign cell
membranes (lysis).
 Immune Responses

The first reaction to an antigen is called a primary immune response.
During this response, antibodies are produced for several weeks. Some B
cells remain dormant as memory cells. A secondary immune response
occurs rapidly as a result of memory cells response if the same antigen is
encountered later.
 Practical Classification of Immunity

Naturally acquired immunity arises in the course of natural events, whereas
artificially acquired immunity is the consequence of a medical procedure.
Active immunity lasts much longer than passive immunity. A person who
encounters a pathogen and has a primary immune response develops
naturally acquired active immunity. A vaccine produces another type of
active immunity. A person who receives an injection of antibodies (vaccine)
has artificially acquired passive immunity.
Adaptive Defenses or Immunity (continued).
 Allergic Reactions
1.
2.
3.
Allergic reactions are excessive and misdirected immune responses
that may damage tissue. They are classified by how quickly they
follow exposure to the allergen.
Delayed-reaction allergy, which can occur in anyone and inflame
the skin, results from repeated exposure to antigens. After the
repeated exposure, the presence of foreign substances activates T
cells.
Immediate-reaction allergy is an inborn ability to overproduce IgE.
The reaction happens within minutes of contact from the allergen.
The immediate reaction allergy activates B cells, which become
sensitized when the allergen is first encountered. Allergic reactions
are triggered. In the initial exposure, IgE attaches to the membranes
of widely distributed mast celled and basophils. When a subsequent
allergen-antibody reaction occurs, these cells release allergy
mediators such as histamine, prostaglandin D2, and Leukotriene's.
mast cells bursting an releasing allergy mediators such as
histamine. The released chemicals cause allergy symptoms such as
hives, hay fever, asthma, eczema, or gastric disturbances.
Adaptive Defenses or Immunity (continued).
 Transplantation and Tissue Rejection
1.
2.
3.
Transplantation of tissues or an organ, such as the skin, kidney,
heart, or liver, from one person to another can replace a
nonfunctional, damaged, or lost body part.
A transplant recipient’s immune system may react against the
donated tissue, an event termed a tissue rejection reaction.
Matching donor and recipient tissues and using immunosuppressive
drugs can minimize tissue rejection. These drugs interfere with the
recipient’s immune response by suppressing formation of antibodies
or production of T cells, thereby dampening the humoral and
cellular immune responses. Immunosuppressive drugs may increase
susceptibility to infection.
A heart lasts 3 to 5 hours outside the body before needing to be
transplanted, a liver lasts 10 hours, and a kidney lasts 24-48 hours.
Adaptive Defenses or Immunity (continued).
 Autoimmunity
1.
In autoimmune disorders, the immune system manufactures
autoantibodies that attack a person’s own body tissues.
Autoimmune disorders may result from a previous viral
infection, faulty T cell development, or reaction to a nonself
antigen that resembles a self-antigen.
Diseases/ Disorders
 AIDS

Human immunodeficiency virus causes AIDS. Gradually shuts
down the immune system.
 Lymphoma

Tumor composed of lymphatic tissue.
 Autoimmunity

Immune system manufactures auto antibodies that attack a
person’s own tissues.
Work’s Cited Page
 Oakes, David D. "Thymus." World Book Advanced.
World Book, 2013. Web. 19 Mar. 2013.
 Land, Michael H. "Immune system." World Book
Advanced. World Book, 2013. Web. 19 Mar. 2013.
 Schmid-Schoenbein, Geert W. "Lymphatic
system." World Book Advanced. World Book,
2013. Web. 19 Mar. 2013.
 Shier, David, Jackie Butler, and Ricki Lewis. Hole's
Essentials of Human Anatomy and Physiology.
9th ed. Boston, Burr Ridge, IL, Madison, WI, New
York, San Francisco: tion, 2006. 360-381. Print.