Lecture 9 9/14/23 Flashcards
What is the 1st order cytokine for Th1 activation?
IFN-gamma
What is the 1st order cytokine for Th2?
IL-4
What is the 2nd order cytokine for Th1?
IFN-gamma
What are the 2nd order cytokines for Th2?
-IL-4
-IL-5
-IL-13
What are the 2nd order cytokines for Th17?
-IL-17A
-IL-22
Which molecule mediates humoral immunity?
antibodies
Which markers are present on the surface of B bells?
-CD21
-CD19
-CD40
-MHC-II
What are BCRs?
-immunoglobulins/”antibodies” on the surface of B cells
What type of immunity can be transferred via bodily fluids?
antibody-mediated
What is passive immunity?
immunity acquired by receiving pre-formed antibodies from an external source
What type of immunity is offered by passive immunity?
temporary, immediate immunity
What are maternal antibodies?
antibodies passed from the mother to the newborn through the placenta or through breast milk
What is antibody therapy?
pre-formed antibodies administered to patients
How can active immunity be developed?
-recovery from a microbial infection
-vaccination
What are the initial steps in B-cell differentiation?
-bacteria infect and replicate
-dendritic cells are activated
-T and B cells primed in lymph node
-adaptive immunity activated; B cells differentiate
What are the characteristics of plasma cells?
-differentiated B cells
-generate thousands of immunoglobulins each second
-short-lived
What are the characteristics of memory B cell responses?
-few cells respond initially
-memory B cells accumulate with each exposure, leading to greater responses
What signals are needed for complete activation of B cells?
-helper T cell TCR/MHC-II
-CD4
-CD40/CD40L
What is somatic hypermutation?
process that introduces random genetic mutations into the B cell’s antibody genes to improve specificity
How does affinity factor into B cell survivability?
-if mutation increases binding affinity, B cell will survive and keep proliferating
-if mutation reduces binding affinity, B cell will undergo apoptosis
Why do B cells with non-specific immunoglobulins undergo apoptosis?
to prevent antibodies/immunoglobulins that bind to host molecules
What is affinity maturation?
process of increasing antibody activity through multiple rounds of somatic hypermutation
Where does affinity maturation occur?
germinal centers
