Immunology Flashcards
Innate immune responses
Immediate, not specific, no memory
Immunology
The study of the body’s defense against infection including physical barriers, innate and acquired immunity
Adaptive or acquired immunity
Takes time to develop, specific, immunological memory
Antigen
Stimulates ANTIbody GENeration
Granulocytes
Neutrophils, eosinophils and basophils
Agranulocytes
Lymphocyte, monocyte
Cytokines
Used by the innate immunity to recruit immune cells to the site of infection
Cells of the innate immune system
Dendritic cells, cytokines, macrophages (monocytes), neutrophils
Phagocytic cells in innate immunity
Macrophages (monocytes) and neutrophils
Natural killer cells of innate immunity
Large, granular lymphocytes, attack viral infected cells and cancer cells
TLRs
Toll-like receptors located on the membranes of immune cells such as monocytes and dendritic cells
Inflammation
Induced by cytokines that are triggered by TLRs
Anatomical barriers
Skin, mucous membranes
Physiologic barriers
Temperature, low pH, chemical mediators
Inflammatory barriers
Tissue damage and infection induce leakage of vascular fluid which contains serum proteins with antibacterial activity, influx of phagocytic cells
Antigen presenting cells
Dendritic cells and macrophages, bridge between innate and adaptive immunity
Acquired (adaptive) immunity
Response of lymphocytes to specific antigen, immunologic memory, active and passive
Cells of adaptive immune system
Cytotoxic T cells (CD8), helper T cells (CD4), suppressor T cells, B cells
T lymphocytes
Cellular immunity and regulation
B lymphocytes
Produce antibodies, humoral
Ig
Protein that can bind to an antigen
Functions of immunoglobulins
Neutralize, opsonization, agglutination, activate complement, increase natural killer cell activity
Opsonization
Coat/cover bacteria to enhance attractiveness of foreign agent to macrophages and neutrophils
Agglutination
Multiple pathogens are aggregated by antibody molecules
IgM
First Ig produced after infection, activates complement
Pentamer
IgG
Most abundant, opsonizes and neutralizes viruses and toxins
Monomer
IgA
At mucosal surfaces, neutralizes bacteria and viruses
Dimer
IgE
Binds avidly to mast cell membranes, allergies
Monomer
IgD
Acts as an antigen receptor on B cells, not much secreted
Monomer
Two ways to provoke active acquired immunity
Infection with organism and vaccination
Passive acquired immunity
Gift of premade antibodies, short lasting, 2 weeks to 6 months
Three types of passive acquired immunity
Natural, blood serum injections, laboratory produced antibodies
Natural passive acquired immunity
Via trans-placental transport or via colostrum
Species with trans-placental transport of antibodies
Humans, monkeys, rodents, dogs, cats
Species with no trans-placental transfer of antibodies
Horse, cow, sheep, pig, goat
Blood serum injections
Blood from hyper-immune animals are injected into another animal, gives about 2 weeks of protection
