Topic 15 - Adaptive Immunity Flashcards
What is innate immunity (spec/speed?)
Non-specific & fast
What is adapative immunity (spec/brain?)
Specific & has memory
What are the two ways innate immunity works?
- Physical barriers
2. Chemical/cellular responses
What is the way that adaptive immunity works?
Lymphocytes & antibodies
What are the physical barriers?
- Skin
- Mucous membranes
- Normal microbial flora
What are the chemical/cellular responses?
- Phagocytic WBC
- Antimicrobial substances
- Inflammation
- Fever
What are the ways lymphocytes & antibodies work?
- Specialized lymphocytes (B cells and T cells)
- Antibodies
What is specificity?
Recognizes a particular molecule (antigen)
What is inducibility?
Cells get activated only in response to specific pathogens
What is clonality?
Active cells duplicate themselves (clones)
What is no response to self?
The immune system doesn’t attack its own body (hopefully)
What is memory?
Remembers and reacts faster during a second exposure to pathogen
What 5 things make up adaptive immunity?
- The lymphatic system
- Antigens
- Antibodies
- Lymphocytes (B cells and T cells)
- Chemical signals and mediators
What is lymph?
Plasma and solutes from blood
What are lymph nodes?
Receive lymph and interact with immune cells?
What is the lymph system?
One-way vessels carry lymph from tissues back to blood
What are antigens?
Specific 3D molecules recognized by antibodies
- Usually proteins, lipids & glycolipids
What is an example of an antigen?
- Surface structures found on bacteria or viruses
2. Soluble proteins or toxins
What are antibodies used by?
- Used by the immune system to recognize foreign particles
- Have variable and constant regions
What are antibodies also known as?
Immunoglobulins
What are antibodies?
Special molecules that bind antigens
How many chains do antibodies have?
4 (2 “light” and 2 “heavy”)
What is the variable region on the antibody?
The portion that recognizes a very specific antigen
What is the constant region on the antibody?
It is recognized by immune cells
Define antigen
A molecule (usually a foreign protein) that is bound by antibodies
Define epitope
The specific region of an antigen that is bound by a specific antibody (there may be several per antigen)
Describe the antibody (epitope)
A molecule that specifically recognizes and binds a particular epitope on an antigen
What are the 5 functions of antibodies?
- Activate complement system
- Neutralize toxins
- Opsonization
- Agglutionation
- Antibody-dependent cellular cytotoxicity (ADCC)
What is the complement system?
Set of roughly 30 proteins that can trigger inflammation/fever, opsonization, pathogen, lysis, etc
Define opsonization
Stimulate phagocytosis by neutrophils & macrophages
Define aggultionation
Antibodies bind multiple antigens (clump together) increases chances of phagocytosis & reduces solubility
What is antibody-dependent cellular cytotoxicity (ADCC)?
Non phagocytotic killing mediated by natural killer (NK) cells, neutrophils, eosinophils
Name 5 different antibodies
IgG, IgA, IgM, IgE, IgD
What do IgD antibodies do?
May activate B cells, mast cells, and basophils
What do IgE antibodies do?
Triggers release of anti-parasitic molecules from eosinophils, and histamines from basophils
What do IgM antibodies do?
Complement activation, neutralization, agglutination
What do IgA antibodies do?
Dimer is secreted by mucous membranes, also found in milk
What do IgG antibodies do?
Complement activation, opsonization, agglutination
- Can cross placenta to protect fetus
What is ELISA?
A test used to detect the presence of an antigen or antibody in a sample (can be used as a pregnancy test)
What is basophil involved in?
Inflammation
What is the dendiritic cell involved in?
Phagocytosis
What are lymphocytes?
Specific types of leukocytes (WBC)
What are macrophage, neutrophil, and eosinophil part of?
Phagocytosis and non-phagocytic killing
