Immunology: Basic concepts Flashcards
What are antibodies?
Proteins that respond to B cells finding antigens and bind
What are cytokines?
Proteins that switch on/off through molecular communication and influence other proteins
What are chemokines?
Give migrational directions
What is inflammation?
Attempt to restore homeostasis
Second line of defence
What are the innate immune cells?
Macrophages and Neutrophils
Explain macrophages
Big eaters, phagocytic, cytokine production
Explain neutrophils
Produce ROS that kill pathogens
Highly motile
Phagocytic
Explain pattern recognition receptos
Leukocytes co-express many different ones
Recognise key pathogen components
Explain lymphocyte receptors
Can recognise almost anything
What are the two adaptive lymphocytes?
B cells and T cells
Explain B cells
Develop in bone marrow
Produce antibodies
Explain T cells
Develop in bone marrow - mature in thymus
CD4+, CD8+, regulatory
Explain dendritic cells
Innate
PRR
Mature in response to danger
Explain lymphocyte activation
Antigens processed and presented correctly
What cells present antigens to T cells?
Mature dendritic cells
What cells present antigens to B cells?
T cells or pattern recognising receptors
What is clonal selection?
First response to lymphocyte activation
Antigen-driven, antigen-specific proliferation
What are the immune effector mechanisms in T cells?
CD4 helper T cell, Th1 T cell, Th2 T cell, CD8 cytotoxic cells
Explain Th1 T cells and Th2 T cells
Th1 T: product cytokines - phagocytosis
Th2 T: produce cytokines - B cells make better antibodies
Explain CD4 and CD8
CD4: cytokine factory - against extracellular pathogens
CD8: snipers - intracellular pathogens
What are the immune effector mechanisms in B cell activation?
Opsonisation: improve phago.
Complement fixation: direct killing
Degranulation: release of vesicles
