Linking Innate And Aaptive Immunity Flashcards
Outline the 3 major immune cell communication methods
Soluble molecules (cytokines or chemo lines) binding to receptors on a cells membrane
Cell surface-bound receptors binding to cel surface-bound ligand
Antigen (pathogen parts) being presented to cell surface bound receptors
Outline soluble chemical messengers binding to receptors
Common building blocks, or immune cell secretions bind toll like surface receptors.
Toll receptors recognise ligands, and activates up/down regulation of various genes to act accordingly
What are cytokines, and their receptors
Cytokines are molecules such as interleukins and interferons that control growth and activity of immune cells.
Cytokine receptor
What are chemokines and their receptors
Type of cytokine that are involved in the immune response by directing the migration of immune cells to sites of infection/inflammation (chemokinesis).
Chemokine receptors
What molecules do chemokines activate
Molecules that direct cell movement via chemotaxis
How does cell-cell binding interactions alter cell function
Can alter, one of or both of the cells involved
Outline Antigen being presented to a cell surface bound receptor
Dendritic cell shows small pieces of broken down pathogen to T cell through T cell receptor (T cell exclusive) - functions to activate T cell. T cell up/down regulate transcription processes to fight infection/inflammation.
What is an antigen
Anything that has the potential to be recognised by the immune system.
Foreign antigen: anything from “outside”
Self antigen: immune system usually tolerant of self antigen
Outline how activated dendritic cells communicate with T cells
Up regulate gene expression of cytokines - bind to T cell receptors.
Have surface bound receptors that bind to T cell surface bound ligand (or vice versa).
Present antigen to T cell surface bound receptors
What does dendrite/T cell communication lead to
This communication leads to activation of the T cell
It is an example of innate and adaptive immune responses interaction
What type of protein does dendritic cells use to present antigen to T cell
Major Histocompatibility complex MHC
What are the 2 types of MHC
MHC-1 presents endogenous intracellular antigen. Expressed on all uncleared cells (virus e.g. can infect all cells, thus all cells can alert immune system.
MHC-2presents exogenous extracellular antigen (phagocytes pathogen). Only expressed on antigen presenting cells e.g. dendritic cells
Where are cytokines and chemokines produced
Both are produced by innate and adaptive immune cells as well as cells that influence the immune system
How can helper T cells that have been activated by a dendritic cell help B cells
Making cytokines that bind to receptors on B cell membranes.
Have cell surface bound receptors that bind to a B ell surface bound ligand or vice versa).
This communication leads to activation of the B cell and helps the B cell to make antibodies
What compliment pathways can antibody binding to a pathogen trigger
Antibody binding to a pathogen can trigger the classical pathway of compliment activation, and compliment fragments that are bound to antigen can also help activate B cells to make antibodies.
Both examples of how innate and adaptive immunity interact with each other.
