Micro Lecture Exam 2 Flashcards
Immunology
Define immunology
The study of all features of the body’s second and third lines of defense towards infectious agents, allergies and cancer
What are WBCs looking for when theyre moving around the body?
Self and nonself
Neutrophils (WBCs)
cells made from bone marrow that go around the body
Phagocytosis
Cell is eating something; most common method of destruction
How are bacterias destroyed by the WBCs?
When a pathogen is engulfed by a WBC, it forms a phagosome, which fuses with lysosomes to form a phagolysosome. The enzymes within the lysosome then destroy the pathogen
What do Markers/Antigens do?
Allows cells to identify new ones and then initiates a new response from the cells to destroy it
PAMPs
Pathogen-associated molecular patterns
Bacterial PAMPs
peptidoglycan and lipopolysaccharide
What is a viral PAMP?
double stranded RNA
PRRs
Pattern recognition receptors that are used by phagocyte host cells during the second line of defense
Are all nonself proteins destroyed?
If they are not harmful, the immune system will signal the cells to react differently
MPS
Mononuclear phagocyte system
Reticulum
a support network of connective tissue fibers that permeate the tissues of the body by interconnecting cells and meshing with the connective tissues surrounding the organs
What is MPS?
Phagocytic cells that provide a passageway between tissues and organs and in direct contact with tissue cells and the extracellular fluid
Where are MPS found?
Thymus
Lymph nodes
Tonsils
Spleen
Lymphoid tissue of the mucosa of the gut and respiratory tract
What are the WBCs in the MPS called?
Macrophages; they wait until an alien arrives to an MPS location
Innate defenses
Protections we are born with that protects against many pathogens
Adaptive defenses
Protections developed through life and are carried out by lymphocytes
First line of defense
Skin, mucous membranes, gastric acid
Second line of defense
Phagocytes, fever, antimicrobial proteins and inflammation
Types of Phagocytes
Neutrophils, dendritic cells and macrophages
Signs of inflammation
Rubor
Calor
Tumor
Dolor
Loss of function
Rubor
redness caused by increased circulation and vasodilation in the injured tissue
Calor
warmth caused by the heat given off from the increased blood flow
Tumor
swelling caused by fluid escaping into the tissues
Dolor
Pain caused by the stimulation of nerve endings
Stages of inflammation
- Vasodilation
- Increased permeability of blood vessels in the area
- Phagocyte migration
- Repair
What happens during vasodilation?
Increased diameter of arterioles which causes redness and heat of skin area
What happens during increased permeability of blood vessels?
The antibodies and clotting factors that were in the blood are allowed to leave which causes swelling and pain of area
PYOgenic (not pyrogenic)
bacteria that stimulate the formation of pus
Abscess
excessive pus in an enclosed space
Ulcer
Inflamed tissue which is shed too many times at one site to form an open sore
Exudates
fluids, cells, proteins or other substances that are released from blood vessels into tissues as a result of inflammation, infection, or injury
Third line of defense
specific host defense (B cells, antibodies, T cells)
How do cells determine which cells are self?
by interacting with other surface antigens
Three main types of phagocytes
Macrophages, neutrophils, dendritic cells
What part of the brain is body temperature is controlled by?
Hypothalamus
How do phagocytes recognizes PAMPs?
Phagocytes recognize PAMPs by binding them with PPRs.
Exogenous pyrogens
substances that originate from outside the body and can induce fever when introduced into the body
Endogenous pyrogens
substances that are naturally produced within the body in response to various stimuli, such as infection, inflammation, or tissue injury. They can also induce fever.
What are three things a fever stimulates?
Immune system, hematopoiesis, and metabolism
Interferons
small proteins produced by white blood cells and tissue cells in response to viral infection
B-cell
bone marrow cell
t-cell
Thymus cell
Immunocompetence
when a person has the ability to react to countless antigens and form a protective immune response even without previous exposure
What two macromolecules usually play as antigens?
proteins and polysaccharides
Where are B and T cells constantly circulating through in the body?
Constantly recirculating through the circulatory system and lymphatics
What type of organs are B and T cells migrating in and out of?
Lymphoid organs
Antigen activated T cells give rise to
T regulatory cells
Cytotoxic cells
T helper cells
Helper T cells (CD4)
Activate macrophages & cytotoxic cells
Assist B-cell process
Regulatory T cells
Controls the T cell response
Cytotoxic Cells (CD8)
Leads to the destruction of infected host cells and other foreign cells
What do plasma cells produce?
produce and secrete antibodies and inactivate the antigen
What 3 cells do B cells differentiate into?
Regulatory, plasma, and memory cells
Regulatory B cells
secretes cytokine IL-10 to help stop the response of inflammatory mechanisms
Natural Immunity
any immunity that is acquired during normal biological experiences of an individual
Artificial immunity
Protection from infection obtained through medical procedures (vaccines)
Active immunity
When a patient receives an antigen that activates B and T cells causing memory cells to activate and respond
Passive immunity
when a patient receives antibodies that were produces actively in the body of another donor
Gamma globulin or IVIG
A substance used for passive immunization that contains immunoglobulin (antibodies) extracted from the pooled blood of many human donors
(particularly those involving immune deficiencies or autoimmune diseases)
What does a vaccine involve?
the inoculation with antigens from a specific pathogen
The Complement System
proteins in blood that are activated to enhance immune, allergic and inflammatory reactions
