Topic F - Autoimmune disorders and the eye P1-2 Flashcards
What is Body defense/immune
system?
a system that provides protection against
pathogens & antigens.
• It can tell the difference between foreign cells and own cells.
Two types: Non-specific (innate) & specific (adaptive)
what is the difference between Non-specific (innate) & specific (adaptive) immunity.
Non-specific (Innate) – before entering blood stream, no memory
Specific (Adaptive) – after entering blood stream, has memory
what are the 4 types of living pathogens and the 2 types of non-living pathogens
living:
- parasites
- protozoa
- fungi
- prokaryote
non-living:
- virus
- prion
what is the main diff between bacteria and virus in how they cause disease?
bacteria cause disease by releasing toxins (poisons), enzyme that damages healthy cells
or enter/destroy healthy cells.
virus cause disease by dismantling metabolic machinery of host cells and destroy
them.
what are the 5 components of non-specific immunity?
- Mechanical barrier
- chemical actions
- phagocytosis
- inflammation
- fever
what are 6 examples of mechanical barriers? what are their functions?
1.Intact skin
Closely packed cells and multiple cell layers prevent entrance of pathogens
- Intact mucous
Closely arranged cells retard entrance of pathogens; not as effective as intact
skin membrane - Mucus
Traps pathogens in digestive and respiratory tracts - Saliva
Washes pathogen from oral surfaces - Tears
Washes pathogens from surface of eye - Urine
Flushes pathogens from urethra
what are 4 examples of chemical action? what are their functions?
- Acid pH of skin
prevents growth of many bacteria - Gastric juice
Kills pathogen that are swallowed - Interferon
Helps to prevent viral infections - Lysozyme
Antimicrobial enzyme in nasal secretions, perspiration, saliva, tears to kill
pathogens
what are 3 examples of other mechanisms? what are their functions?
- Fever
Speeds up body processes and inhibits growth of pathogens - Inflammation
Promotes nonspecific resistance; confines infection - Phagocytosis
Macrophages and granulocytic leukocytes engulf and destroy pathogens
what are the characteristics of specific (adaptive) immune system?
- It is directed at specific pathogens and foreign cells
- It produces a specific cell & substance to attack a specific invader
- It has a “memory”
- For second encounter, the immune response will be faster & stronger
how do b cells and t cells provide immunity?
B cells = antibody-mediated immunity: attack antigen by
producing antibodies
T cells = cell-mediated immunity: attack pathogen/foreign cells
by chemical/physical means (with phagocytosis)
what are the 3 stages of T cell activation immunity response? (ACA)
• 1. Antigen recognition - T cells (TC or TH
) binds to antigen
and activated. They develop a memory of their antigen in
case it appear again.
• 2. Clone formation - the activated T cell divided by itself &
form clone cells (TC or TH
) & memory cells (TM)
• 3. Action - TC directly attack & destroy pathogen. TH binds to
antigen, activated and release cytokines, which promotes
activity of B and TC cells, inflammation and phagocytosis by
neutrophils and macrophages. TM cells launch a secondary
response (stronger & faster) if the antigen reappears.
what are the 5 stages of b cell activation immunity response? (ABCDA)
- Antigen recognition – receptors of B cells binds to antigen
- B cell activation – B cells engulfs antigen. TH come in and binds to antigen and release cytokines to activate B cells.
• 3. Clone formation – activated B cells divided by itself and
form clone cells (B cells)
- Differentiation – Most clone cells become plasma cells. Some become memory B cells.
- Action – Plasma cells produce antibodies to destroy antigen; Memory B cells launch an attack against the antigen if it reappears.
what are the 4 importance of helper T cells?
• It activates phagocytosis/macrophages in the event
of inflammation & fever.
• It releases cytokines to help B cells cloning
themselves and produce antibodies
• It releases cytokines to get cytotoxic T cells to
clone themselves and attack / destroy pathogen
• It tells other T cells what to kill.
what is an autoimmune disease and what causes it?
• Autoimmune Diseases result when B & T cells, for unknown
reasons, recognise certain body tissues as foreign antigens and
produce an immune response against them. This is because
certain body molecules have changed slightly and are no
longer recognizable as self.
hence immune system mistakenly
attacks your body because it cannot tell the difference between foreign cells and own
cells.
Some autoimmune diseases target only one organ. Other
diseases, like systemic lupus erythematosus (SLE), affect the
whole body.
what are 8 early symptoms of autoimmune disorders
- fatigue
- achy muscles
- swelling and redness
- low-grade fever
- trouble concentrating
- numbness and tingling in the hands and feet
- hair loss
- skin rashes
**symptoms may come and go. A period of symptoms is
called a flare-up. A period when the symptoms go away is called remission
