Please enable JavaScript.
Coggle requires JavaScript to display documents.
Immune Hiepsy Barrinetos Anat/ Phy Honors Period 6 - Coggle Diagram
Immune Hiepsy Barrinetos Anat/ Phy Honors Period 6
Major functions of the Lymphatic & Immune systems
Lymphatic system: The network of (lymphatic) vessels through which lymph drains from the tissues and into the blood.
Absorption of fats from the intestine
Responding to bacteria-also-acting as a transport system
Maintains and regulates fluid levels within our tissues by collecting leaked fluids from our blood vessels
Filtering of lymph and blood
Immune system: Acts as the front lines of defense against disease, provides resistances to diseases and pathogens
Respond to pathogens , and or the other disease- causing molecules, to purge them from the body.
Recognize and diminish the effects of bacteria
Eliminate disease-causing "changes" within the body such as cancer cells.
Build further immunity to specific pathogens
Location of Lymphatic organs and their functions
Primary Lymphoid Organs
Thymus: Function- Site of T-cell maturation. Location: Behind breastbone and just above the heart
Redbone marrow: Function- Production of blood cells; site of red and white blood cells (erythrocytes and leukocytes) maturation. Location- found deep in bones' medullary cavities.
Secondary Lymphoid Organs
Appendix: Function- Produce antibodies to prevent/ reduce future infections, Location- End of bowels
Peyers Patches: Function- Prevent pathogens from penetrating mucous membrane; site for lymphocyte activation and proliferation, Location: GI (Gastrointestinal) Tract; Small Intestine
Spleen: Function- Cleanses blood and removes aged or defective Red Blood Cells (RBCs); site for lymphocyte activation and proliferation; stores pallets, monocytes, and iron. Location- Left upper-abdomen (belly) right beneath the diaphragm.
Tonsils: Function- Inhibit germs from entering either the nose or mouth. Location - (back) throat and palate
Lymph nodes: Function- Cleanses lymph; site for lymphocytic activation and proliferation. Location - Found along lymphatic vessels scattered throughout each and every corner of the body
Purpose and examples of First, Second and Third line of defense
Adaptive (specific) Defensive system: A specifc defensive system that eliminates almost any pathogen or abnormal cell in body
Humoral (Antibody- Mediated) Immunity: Antibodies, produced by ;lymphocytes, circulate freely in body fluids; bind temporarily to target cell
Mark for destruction
Cellular (Cell-mediated) immunity: Lymphocytes act against target cell
Indirectly: Releases chemicals that enhance the inflammatory response or active other lymphocytes or macrophages
Directly: Kills infected cells
It is specific and recognizes and targets specific antigens, it is systemic not restricted to intial site, it has memory: mounts an even stronger attack to "nown antigens" (second and subsequent exposures)
Third line of defense: Attacks particular foreign substances and takes longer to react than innate
Innate (Nonspecific) defensive system: Constitutes first and second line of defense
First Line of Defense: External body membranes (skin and mucosae)
Skin and mucous membranes procedure protective chemicals that inhibit or destroy microorganisms
Acid (Mantle): Acidity of skin and some mucous secretions inhibit growth
Enzymes: Lysosomes of slaiva, respiratoy mucus, and lacrimal fluid kills many microorganism; enzymes in stomach kill many microorganisms
Mucin: Sticky mucus that lines digestive and respiratory tract traps microorganism
Physical barriers to most microorganisms: Keratin is resistant to weak acids and bases, bacterial enzymes, and toxins; mucous provide similar mechanical barriers
Second line of Defense: Inhibits the spread of invaders; inflammation is the most important mechanism
Internal defenses: Phagocytes; Natural Killer( NK) cells; Inflammation; Antimicrobial Proteins; fever
Passive vs. Active immunity
Humoral Immune response: When B-Cells encounter target antigens, it provokes the Humoral Immune Response
Active humoral immunity: Occurs when B-Cells encounter antigens and produce antibodies against them
Naturally Acquired: Formed in response to actual bacterial or viral infection
Artificially acquired: Formed in response to vaccine of dead or attenuated pathogens
Passive Humoral immunity: Occurs when ready-made antibodies are introduced into the body
Naturally acquired: Antibodies delivered to fetus via placenta or to infant through milk
Artificially acquired: Immediate protection but ends when antibodies naturally degrade
Innate(natural) immune defenses and Adaptive(acquired) immune defenses
Humoral immune response: When B-Cells encounter target
Tigons, it provokes the humoral
responses
B-Cells are activated when
antigens bind to surface
receptors, cross-linking them
Triggers receptor-mediated
endocytosis of cross-linked antigen-
receptor complexes (clonal
selection), leading to proliferation and
differentiation of B-Cell into effector
cells
Specific antibodies for
that particular antigen
are then produced
Most become clone cells
become plasma cells (antibody
secreting effector cells)
Cellular immune response: Lymphocytes act
against target cell:
indirectly: Releases chemicals that enhance
inflammatory response or activating other
lymphocytes or macrophages
directly: kills infected crlls
T-Cells provide defense
against intracellular antigens, Some T-Cells directly kill cells;
others release chemicals that
regulate the immune response
Usually become Helper T-
Cells (Th) that can activate
B-Cells, other T-Cells, and
macrophages
Some become Regulatory T-
Cells, which moderate the
immune response; can also
become Memory T-Cells
Helper, Cytotoxic, and
Regulatory T-Cells are activated
T-Cels
Disorders associated with the Immune system
Inflammation
Pus: Creamy, yellow fins mixture of dead neutrophils, tissue/cells, and living/dead pathogens
Abscess: Collagen fibers are laid down, walling off sac of pus; may need to be surgically drained
Can grow to be tumor-like growths called granulomas--areas of infected macrophages surrounded by uninfected marcrophages and outer capsule
Some bacteria, such as tuberculosis bacilli, resist digestion by macrophages and remain alive inside
Immune problems:
Organ transplants and preventionof rejection: Success depends on similarity of tissues, ABO, other blood antigens, and MHC antigens are matched as closely as possible
After surgery: Patient treated with immunosuppressive therapy; many of these therapies bear severe side effects, When a patient's immune system is suppressed it cannot protect the body from foreign agents such as bacterial or viral infections
Leading cause of death among transplant recipients
Best circumstances include rejection after ten years in fifty percent (50%) of patients
Immunodeficiencies: Congenital or acquired conditions that impair function or production of immune cells or molecules
Severe combined immunodeficiency (SCID) syndrome: Genetic defect with marked deficit in B and T-Cells
Defensive adenosine deaminase (ADA) enzyme allows for the accumulation of metabolites lethal to T-Cells; fatal if left untreated
Treatment: Bone marrow transplants
Hodgkins Disease: An acquired immunodeficiency that causes the cancer of B-Cells, which depresses lymph-node cells and thus leads to immunodeficiency
Acquired immune deficiency syndrome ( AIDS)
Human Immune Deficiency Syndrome (HIV): Cripples the immune system by interfering with the activity of Helper T-Cells
Characterized by severe weight loss, night sweats, and swollen lymph nodes
HIV is transmitted via body fluids: blood, semen, and vaginal secretions
Opportunistic infections occur
Pneumonia
Kaposi's Sarcoma
Pneumocystis
HIV destroys Helper T-Cells (TH), thereby depressing cellular immunity
Hypersensitivities: Immune responses to perceived (otherwise harmless) threat that cause tissue damage
Also caused Acute (Type 1) Hypersensitivities (Allergies; begin in seconds after contact with allergen (antigen that causes allergic reaction)
Initial contact with allergies is asymptomatic but sensitizes person
Activated IgE against antigen binds to MAST cells and Basophils
Later encounter with the same allergen causes flood of histamine releases from IgEs, resulting in induced inflammatory response
Histamine causes vasodilation and leakiness of the vessels, leading to symptoms of runny nose, itchy hives, or watery eyes
Antihistamines are needed to control
Asthma can occur if allergen is inhaled
Autoimmune Diseases:Results when the immune system loses the ability to distinguish self from foreign
Autoimmunity: Production of autoantibodies and sensitizes Cytotoxic (TC) that destroy body tissues
Type 1 Diabetes Mellitus: Destroys pancreatic cells
Systemic Lupus Erthematosus (SLE): Affects mutiple organs
Graves Disease: Causes hyperthroidism
Multiple Sclerosis: Destroys white matter myelin
Myasthenia Gravis:Impairs nerve-muscle connections
Glomerulonephritis: Damages kidneys
Rheumatoid Arthritis: Destroys joints
Treatment pf autoimmune diseases: Suppress entire immune system, Anti-inflammatory drugs, such as corticosteroids; blocking cytokine action; blocking co-stimulatory molecules
Cells involved in the immune system and their functions
Helper T-cell: Play a central role in the adaptive immune response; activate both humoral and cellular arms
Cytocic T-cells (Tc): Directly attacks and kills other cells
Regulatory T-cells: Important in preventing autoimmune reactions
Adaptive immunity
Monocyte
Eosinophils
Natural Killer(NK) Cells: Nonphagocytic, large granular lymphocytes that police blood and lymph
Basophils
Macrophages: Develop from Monocytes and are the chiel phagocytic cells; most robust of the phagocytic cell
MAST Cell
Neutrophils: Most abundant phagocytes, but die fighting; become phagocytic on exposure to infectious material
B-cell:Depending on form of differentiation, either antibodies are produced (Plasma Cells) or immunological memory is formed for later/subsequent response of the same pathogen (Memory B-Cell)
Killer T-cell
Antigen- Presenting Cells: Engulf antigens and present fragments of antigens. T-Cells for recognition
Macrophages: Widely distributed in connective tissues and lymphoid organs; present antigens to T-Cells, which not only activates T-Cells, but also further activates the macrophage
B-cells: Do not activate naive T-Cells; present antigens to Helper T-Cells to assist their own activation
Dendritic cells: Found in connetcive tissue and epidermis
Antigens and Antibodies
Antibodies go after
extracellular pathogens; they do not invade solid tissue unless a lesion is present
Antigen-antibody complexes do
not destroy antigens; they
prepare them for destruction by
innate defenses
Capable of specificaly
binding with antgen
detected by B-Cells
Antibodies
(Immunoglobulins)
Proteins secreted by B-Cells
Antigen-presenting cells: engulf antigens and present fragments of antigens, T-cells for recognition
Antibody classes: Antibodies are group into
one of five lg Classes
There are five major classes which are: IgM, IgA, IgD, IgG, and IgE
Antibody targets and functions
Antibodies do not destroy antigens;
they inactivate and tag them
Form antigen-antibody
(immune) complexes, Defensive mechanisms
used by antibodies
Neutralization: Simplest, but one of the most
important defensive mechanisms
Agglutination: Allows for antigen-antibody complexes to become cross-linked into large lattice-like clumps
Precipitation: Soluble molecules are cross-linked into complexes; complexes precipitate out of solution; precipitated complexes are easier for phagocytes to engulf
Complement fixation: Main antibody defense against cellular antigens; when several antibodies are bound close together on the same antigen, complement-binding sites on their stem regions are aligned
Basic antibody structure: Overall T- or Y-Shaped antibody monomer consists of four looping polypeptide chains linked by disulfide bonds
Variable (V) Regions at one end of
each arm combine to form two identical antigen-binding sites
Artificial vs. Naturally acquired immunity
active humoral ummunity
two types of active humoral immunity
artificially acquired: Formed in response to vaccine of
dead or attenuated pathogens
naturally acquired: Formed in response to actual
bacterial or viral infection
occurs when B-Cells encounter
antigens and produce
antibodies against them
passive humoral immunity
Occurs when ready-made
antibodies are introduced into
the body
B-Cells are not challenged by
antigens- immunological memory
does not occur: protection ends when
antibodies degrade
two types of passive humoral immunity
naturally acquired :antibodies delivered to fetus via placenta or to infant through milk
artificially acquired : immediate protection but ends when antibodies naturally degrade