Public Health Week Two
I. Immunology
a. Vocabulary and Key Terms
i. Antibody – A substance created by the body to bind pathogens (made by B cells)
ii. Antigen – A protein on a pathogen that is recognized by antibodies.
iii. Antigen Presenting Cell – Cells presenting proteins to T lymphocytes to “teach” them an antigen
iv. B-cell – Cell made in the bone marrow, makes antibodies in response to antigens
v. Commensals – natural organisms lining the body
vi. CMI – cell mediated immunity, a type of adaptive immunity
vii. Complement – Plasma proteins which attempt to kill extracellular pathogens
viii. Cytokine – chemicals influencing the behavior of other cells
ix. Cytotoxic T-cell – T cells which directly kill infected cells
x. Dendritic cell – Antigen presenting cells with branching morphology, found in tissues
xi. Epitopes – Antibody binding sites
xii. Helper t-cell – T-lymphocytes which secrete cytokines
xiii. IgE – parasitic and autoimmune response
xiv. IgM – first responders, cannot get through blood brain barrier
xv. IgG – secondary responders
xvi. Immunoglobulin – Antibodies, IgG, IgA, IgM, IgE, IgD
xvii. Innate immunity – Non-specific immunity, 2 types: barriers and phagocytes
xviii. Interferon – cytokines which help cells fight off viral infections
xix. Lymph – fluid carried by the lymphatic system
xx. Lymph nodes – secondary lymphoid tissue, between lymphatic junctions
xxi. Lymphocytes – white blood cells in the adaptive immune response
xxii. Lymphoid organs – Primary: thymus, bone marrow, Secondary: spleen, tonsils, adenoids, mucosa
xxiii. Macrophage – mononuclear cells in most tissues
xxiv. Mast cells – cells which bind to IgE and play huge parts in allergy response
xxv. Memory cell – B or T lymphocytes which remember past infections
xxvi. Monocyte – white blood cell, eventually becomes a macrophage
xxvii. Mucosa – lining around all entrances to the body
xxviii. Natural killer Cells (NK) – cytotoxic lymphocytes in the blood
xxix. Neutrophil – phagocytic white blood cell, innate immunity
xxx. Plasma cell – terminally differentiated B cells
xxxi. T-cell – cells which matured in the thymus and are responsible for cell-mediated immunity, destroy processed and internalized pathogens
b. Functions of the immune system
i. Prevent Infection
1. Recognize pathogens
2. Prevent spread
3. Eliminate them
ii. Eradicate infections
iii. Important traits:
1. Self vs. non self discrimination
a. Problems
i. Graft rejection
ii. Hypersensitivity-4 types
1. Type one, allergens basophil + mast cells releases histamines, IgE antigens
iii. Autoimmunity-hypersensitivity to self antigens
c. Two Types of Immunity
i. Innate –nonspecific, less effective
1. Barriers
a. Cilia
b. Skin
c. Lysozyme
2. Phagocytes, Natural Killers cells (NK)
a. Monocytes- found in the blood
b. Macrophage- found in the tissues
i. Lives after engulfing pathogen
c. Neutrophils, pus cells
d. LGL –(NK)
i. Dies after engulfing pathogen
ii. Acquired – specific, takes longer
1. Characteristics:
a. Adaptation
b. Specificity
c. Memory
2. Two types:
a. Cell mediated
i. T-cells
1. Made in the thymus (primary)
2. CMI (cell mediated immunity)
a. Cytotoxic-direct kill
b. Helper-activate other help support
i. Produce cytokines
c. Memory-long lasting
d. Suppressor-keep immune system in check
3. Processed only
4. Intracellular
5. Proteins only
b. Humoral
i. Mediated by antibodies
1. Neutralization –block attachment and invasion
2. Complement Activation –plasma proteins which help fight antibodies
3. Opsonization – enhanced phagocytosis
4. Antibody-dependent cellular cytotoxicity – kills cells with help from antibodies
5. Antibodies in five classes
a. IgG
i. Most common, long lasting
b. IgA
i. Mucosal immunity
c. IgM
i. First response, cannot cross the blood brain barrier
d. IgE
i. Parasites and allergies
e. IgD
ii. B-cells
1. Made in the bone marrow (primary)
2. No processing necessary
3. Extracellular
4. Destroys everything
