Module 1: Immunology Flashcards
Define: Immunology
Study of Chemical and Cellular defense against foreign substances
Define: Immunity
Body’s resistance to disease-causing microorganisms and damage by foreign substances
Innate Host Response is also called?
Natural/Native Immunity
What is Innate Host Response (Natural/Native Immunity)?
Non-specific, general recognition and response to “foreign” substance.
What kind of Barriers are used in Innate Host Response (Natural/Native Immunity)?
Physical and Chemical Barriers (e.g. Skin and mucous; certain proteins in blood and specific tissue cells; inflammation, phagocytosis)
What determines the nature of the Innate Host Response (Natural/Native Immunity)?
Route of transmission or portal of entry and type of microbe
What other names can Adaptive Immunity Response have?
Acquired Immunity Response or Induced Immunity Response
What is Adaptive (Acquired/Induced) Immunity Response?
- Specific response to “foreign” substance (usually microbe)
- Pre-committed cells and tissues respond against the “foreign” substance
- Chemical actions from certain cells
- Antibodies specifically against the microbe
What is Immune Response?
A sequence of related host defense events beginning when a host encounters a substance as being “foreign” or “non-self” and leading to cellular and chemical defensive action
Define: Antigen (Ag)
A foreign substance, such as microorganism, which triggers the immune response.
Define: Antibody (Ab) [Immunoglobulin (Ig)]
Antigen-specific proteins which bind to the antigen and assist in inactivating the antigen
Define: Phagocytes
Certain White Blood cells that ingest and digest (kill) invading microbes
What role do the Lymph nodes and Spleen play in immunity?
Site of some immune response activities
What cells originate in the Bone Marrow?
Stem Cells
What cells will the stem cell mature into?
- Erythrocyte (Red Blood Cell)
- Neutrophils
- Eosinophil
- Basophil
- Monocyte
- Lymphocytes
White blood cells are also called?
Leukocytes
Which Leukocytes are classified as Granulocytes?
Neutrophils
Eosinophil
Basophil
What are the characteristics of a Neutrophil?
- Primary phagocytic Cell
- Mature at rate of 10^10
- Circulate about 6.5 hrs. Then adhere to endothelium of blood vessels and wait to respond to inflammation
Which Leukocyte is numerous in allergic responses.
Eosinophils
Which Leukocyte (White Blood Cell) is involved in the inflammatory process?
Basophils
This Leukocyte is moderately phagocytic. Matures into Macrophages and dendritic cells. Responds to inflammation signals.
Monocyte
The primary Phagocyte Cells are?
Macrophages and Neutrophils
A Macrophage is how many times larger than a monocyte when mature?
10 times
What are some key characteristics of Macrophages?
- Large phagocytic cells (mature from monocyte)
- Major Phagocytic cells, not as numerous as neutrophils
- Possess many broad-specificity receptors enabling it to capture a wide range of pathogens
- Major line of defense (Phagocytosis and antigen presentation) against invading microbes and abnormal or defective host cells
- Can serve as Antigen-Presenting Cells (APC)
Define: Innate Host Response (Natural/Native Immunity)
Nonspecific, general response to “foreign” substances, including INFLAMMATORY RESPONSE. (Not directly part of the immune system)
What types of response occurs with Innate Host Response?
Physical and Chemical Barriers
How is defense accomplished with physical and chemical barriers in Innate Host Response?
- Skin and Mucous
- Certain proteins in blood and from specific tissue cells
- Phagocytosis
What determines the nature of the response?
Route of transmission or portal of entry and type of microbe.
Characteristics of Inflammatory Response?
Chemicals in serum and tissues respond to antigen presence- kinins, fibrinopeptides, clotting factors, lysozyme, histamine, cytokines, etc..
What occurs in a chemical response?
- Vasodilation and increased permeability of capillaries (blood vessels become “leaky”
- “Call” phagocytic white blood cells to move to the site of invasion and assist in killing (removing) the invading microbe.
- Phagocytosis occurs, often producing pus (debris of phagocytes and bacteria) and swelling
What is phagocytosis?
Antigenic substance is engulfed and digested by certain white blood cells. (Phagocyte will have a sticky surface)
What are the primary cells involved in Phagocytosis?
Macrophage and Neutrophil
What is Chemotaxis?
- Movement of phagocyte toward the site of inflammation/intrusion.
- “Called by cellular products or complement components (C5a)
What is adherence (phagocytosis process)?
Phagocyte adheres to antigen/intruder
May be hindered by bacterial capsule or surface protein
Describe Ingestion during phagocytosis?
- Pseudopod of phagocyte surrounds the foreign material
- Phagocyte encloses the foreign material into a phagosome
How is digestion accomplished in phagocytosis?
- Lysosomes (cytoplasmic granules) containing powerful digestive enzymes and bactericidal substances
- Lysosomes combine with phagosomes forming phagolysosomes in which the foreign material is digested (killed)
- Waste is discharged.
What is an Antigen (Ag)?
Specific “foreign” substance which STIMULATES an IMMUNE RESPONSE (immunogenic) when introduced into the body and REACTS with ANTIBODIES or T-CELL RECEPTORS
Characteristics of Antigens (Ag)?
- Substance appears foreign to host’s immune system (May be human host’s body constituents (self) that are damaged or malfunctioning (autoimmunity)
- Relatively large molecule (Molecular weight 10,000+)
- Chemical nature- protein with complex 3-D Configuration
What factors contribute to the ability or quality of a molecule to be a good immunogen (ie. Quality and degree of host response)
Route, quantity, timing, and ability to be degraded