1. Biology, 9th ed, Sylvia Mader
Chapter 35
Chapter 35
Lymph Transport & Immunity
Lymph Transport & Immunity

2. Outline The Lymphatic System Nonspecific Defenses Specific Defenses
Lymph Vessels
Lymphoid Organs
Nonspecific Defenses
Barriers
Inflammatory Response
Specific Defenses
Antibodies
T Cells
Induced Immunity
Active versus Passive Immunity
Immunity Side Effects
Allergies
Blood Typing

3. Consists of lymphatic vessels and the lymphoid organs
The Lymphatic System
Consists of lymphatic vessels and the lymphoid organs
Three main homeostatic functions:
Lymphatic capillaries take up and return excess fluid to the bloodstream
Lacteals receive lipoproteins and transport them to the bloodstream
Helps defend body against disease

4. Lymphatic System

5. The Lymphatic Organs

6. One-way system that begins with lymphatic capillaries
Lymphatic System
One-way system that begins with lymphatic capillaries
Take up fluid that has been diffused from, and not reabsorbed by, blood capillaries
Edema - Localized swelling due to accumulation of tissue fluid
Lymph flows one way
From a capillary to ever-larger lymphatic vessels
Finally to a lymphatic duct, which enters a subclavian vein

7. Lymphoid Organs
Lymph Nodes - Capsule surrounding two distinct regions, cortex and medulla
Lymphocytes congregate in cortex when fighting off a pathogen
Macrophages concentrated in medulla - cleanse lymph
Lymph nodes named for their location

8. Lymphoid Organs Tonsils Spleen
Patches of lymphatic tissue located around the pharynx
First to encounter pathogens that enter via the nose and mouth
Spleen
Located in upper left region of abdominal cavity just beneath diaphragm
Cleanses blood

9. Lymphoid Organs Thymus Gland Red Bone Marrow
Located along trachea behind the sternum in upper thoracic cavity
Produces thymic hormones
Red Bone Marrow
Origin for all types of blood cells
Area of maturation for most white blood cells

10. Immune System Nonspecific Defenses
Barriers to entry serve as mechanical barriers
Skin
Mucous membranes lining respiratory, digestive, and urinary tracts

11. Inflammatory Reaction
Nonspecific Defenses
Inflammatory Reaction
Damaged cells and mast cells release histamine and kinins
Capillaries dilate and become more permeable
Enlarged capillaries cause skin to redden
Swollen area and kinins stimulate free nerve endings causing pain

12. Inflammatory Reaction
Neutrophils and monocytes migrate to the site of injury
Neutrophils and mast cells phagocytize pathogens
Monocytes differentiate into macrophages

13. Inflammatory Response

14. A collection of plasma proteins
Complement System
A collection of plasma proteins
Activated when pathogens enter the body
Complements certain immune responses
Interferon binds to receptors of non-infected cells
Causes them to prepare for possible attack
Produce substances that interfere with viral replication

15. Action of the Complement System Against a bacterium

16. Specific Defenses
An antigen is any foreign substance that stimulates the immune system to react
Lymphocytes capable of recognizing antigens
Have antigen receptors on plasma membrane
Protein’s shape allow it to combine with a specific antigen

17. Immunity primarily the result of
Specific Defenses
Immunity primarily the result of
B lymphocytes
B cells give rise to plasma cells
Produce antibodies
T lymphocytes
T cells directly attack cells that bear non-self proteins

18. Antibody-Mediated Immunity
Clonal selection theory:
The antigen selects which lymphocyte will
Undergo clonal expansion, and
Produce more lymphocytes
If the same antigen enters the system again
Memory B cells quickly divide
Give rise to more lymphocytes capable of quickly producing antibodies

19. Clonal Selection Model as it Applies to B Cells

20. Immunoglobins
IgG - Main antibody type in circulation
IgM - Found in circulation Largest antibody
IgA - Found in secretions
IgD - Found on surface of immature B cells
IgE - Found as antigen receptors on basophils in blood and on mast cells in tissue

21. Structure of an Antibody

22. Requirements for T cell antigen recognition:
T Cells
Requirements for T cell antigen recognition:
Antigen must be presented by an antigen- presenting cell
Antigen is first linked to a major histocompatibility complex (MHC) protein in the plasma membrane
Cytokines - signaling chemicals that stimulate various immune cells

23. Clonal Selection Model as it Applies to T cells

24. Types of T Cells Cytotoxic T Cells Helper T Cells
Destroy antigen-bearing cells
Contain Perforins
Helper T Cells
Regulate immunity by secreting cytokines

25. Cell-mediated Immunity

26. Overview of Nonspecific and Specific Defenses

27. Induced Immunity Active Immunity Immunization
Pathogens or pathogen products treated to remove virulence
Dependent upon memory B cells & memory T cells capable of responding to lower doses of antigen

28. Active Immunity Due to Immunizations

29. Passive Immunity Passive immunity
Occurs when an individual is given prepared antibodies (immunoglobins) to combat a disease
Short-lived
Newborns are often passively immune due to mother’s blood

30. Passive Immunity

31. Cytokines and Immunity
Signaling molecules produced by lymphocytes, monocytes, or other cells
Both interferon and interleukins have been used as immunotherapeutic drugs
Enhance the ability of the individual’s T cells (and B cells) to fight cancer

32. Production of Monoclonal Antibodies

33. Immunity Side Effects Allergies
Hypersensitivities to substances that ordinarily would not harm the body
Immediate Response
IgE antibodies
Delayed Response
Memory T cells

34. Immunity Side Effects Blood Type Reactions ABO blood typing
Two self antigens - A and B
If same antigen and its antibody are present in the blood, agglutination occurs
Rh blood typing
People that are Rh+ have Rh factor
People that are Rh- do not have Rh factor
Rh- individuals may produce antibodies to Rh factor if exposed

35. Blood Transfusions

36. Hemolytic Disease of the Newborn

37. Immunity Side Effects Tissue Rejection Autoimmune Diseases
Antibodies and cytotoxic T cells bring about destruction of foreign tissues in the body
Immune system is correctly distinguishing between self and nonself
Autoimmune Diseases
Cytotoxic T cells or antibodies mistakenly attack the body’s own cells

38. Review The Lymphatic System Nonspecific Defenses Specific Defenses
Lymph Vessels
Lymphoid Organs
Nonspecific Defenses
Barriers
Inflammatory Response
Specific Defenses
Antibodies
T Cells
Induced Immunity
Active versus Passive Immunity
Immunity Side Effects
Allergies
Blood Typing

39. Biology, 9th ed, Sylvia Mader
Chapter 35
Ending Slide Chapter 35
Lymph Transport & Immunity
Lymph Transport & Immunity