Active immunity Flashcards
(26 cards)
Recount how T cells are activated by bacterium indirectly
PAMPs on bacterium meet with TLRs on dendritic cells
Bacterium phagocytosed
Inflammation genes activated in dendritic cell
Cell migrates to lymph node
CD28 receptors on antigen-specific T cell meet with CD80/86 on dendritic cell
What types of immunity are B and T cells respectively involved in?
Humoral and cell-mediated
What are Immunoglobulins from B lymphocytes also known as?
Antibodies
Where are immunoglobulins found on T-cells?
T-cell receptors
What two regions make up antibodies/T-cell receptors?
Variable \/ and constant I regions
What do the constant regions do?
Define function of the immunoglobulin
What do variable regions do?
Bind antigens
What does Immunoglobulin G do
Secreted into blood supply and removes pathogens from blood and tissues by binding and recruiting complement leading to pathogen lysis
What does Immunoglobulin A do?
Made by B cells in response to infection of mucosal surfaces,
What does IgE do?
Secreted into blood supply, binds to receptors on mast cells and eosinophils. Opens sites of parasitic infection to rest of immune system.
What determines activity of an immunoglobulin?
The cell it is attached to
What do B cells need to make antibodies?
Help from a T-helper cell
Can immunoglobulin genes rearrange?
yes
What aspects of immunoglobulin-coding genes allow for different variable regions?
Varying, repeating regions. Only some are used to make a protein
What is determined by the first rearraangement?
Diversity and joining regions (DJ recombination)
What is the second rearrangement?
Variable regions
Generally what is the term for what provides diversity in the variable region?
VDJ gene rearrangement
What does VDJ recombination provide diversity to?
Antibodies and T cells
What kind of immunity is gene rearrangement part of?
Adaptive/acquired immunity
How is the right t cell selected for the right B cell?
They rearrange radomly, and the right t cell binds to the antigen triggering cell division (clonal expansion)
How do B-cells become APCs to recruit T-helper cells?
Gene rearrangements hook variable regions to constant region with a membrane anchor. The antibody cannot leave, and can bnd antigens. B cell receptor. allows phagocytosis of antigen
What is the co ligand between an APC B cell and a complimentary T cell
CD40
What happens to the B cells if the anchor stays/is lost
Stays: Becomes a Memory cell.
Leaves: Becomes a plasma cell to secrete immunoglobulins
What does Interleukin 4 drive
Memory cells
