BLOOD 3 Flashcards
Features of acquired immunity?
1) Specificity - response to specific antigen
2) Versatility - ready to confront any antigen at anytime
3) Memory - “remember” any antigen it has encountered
4) Tolerance - responds to foreign substances but ignores normal tissues
How do cells achieve:
1) Specificity
2) Versatility
3) Memory
4) Tolerance
1) Both B and T cells have receptors that recognize specific shapes
2) Different B and T cells have different receptors
3) Some activated B and T cells are long-lasting
4) B and T cells with receptors that recognize self are deleted or not activated
What do B cell receptors bind to?
What do T cell receptors bind to?
Name the receptor T cells bind to?
Extracellular antigens
Antigens displayed on the surfaces of cellular surfaces (e.g macrophages and tissues)
Major Histocompatibility complex
Where do T and B cell encounter antigens?
Which response has a higher anti-body concentration in plasma?
Secondary lymphoid tissues
Origin of the B and T
Where does negative and positive selection occur?
1) T cells
2) B cells
Bone marrow
1) Thymus
2) Bone marrow
What type of immunity are B cells responsible for?
2 steps B cell activation?
Humoral immunity
1) Antigen binds to specific B cell
2) Internalized, digested and combines with MHC Then transported to cell surface
3) Specific helper T cell recognizes antigen and MHC becomes activated and secretes cytokines
Name 3 cytokines released by T and B cll interaction?
IL-4, IL-5 and IL-6
Activated B cells do 3 things?
Become plasma cells
Secrete antibodies
Become memory cells
Six ways in which antibodies protect us?
1) Activate B lymhocytes
2) Acts as opsonins
3) Causes antigen clumping and inactivation of bacterial toxins
4) Activates antibody-dependent cellular activity
5) Triggers mast cell degranulation
5) Activates complement
Five classes of antibodies: list their role:
1) IgG X2
2) IgM X2
3) IgA
4) IgE
5) IgD
1) Most common in blood circulation & Transferred across the placenta from mother to baby
2) First type of antibody to be secreted in response to a new antigen & causing antigen clumping and activating complement
3) Protects mucosal surfaces: especially those present in breast milk
4) Fights parasites and releases histamines
5) Present on B cell surfaces
Types of humoral immunity
Active and passive
Both types of immunity can be: Which type of immunity lasts longer? Vaccination is Artificially acquired: a) Active immunity b) Passive immunity
1) Naturally acquired
2) Active
a) Antigen
b) Antibodies
