intro immunology Flashcards
describe an overview of the immune system
LO
innate immunity
- rapid response
- includes physical barriers (skin, mucosal membranes, saliva, urine, tears) innate immune cells and completment cells
adaptive immunity
- personalised response (takes longer)
- includes adaptive immune cells and antibodies
there is a lot of cross over between these two branches of immunity
what cells are involved in adaptive immunity
what blood borne cells make up the innate immune response
- neutrophils
- macrophages
- basophils
- eosinophils
- natural killer cells
list the steps in inflammation that occur when the mechanical defenses are breached
- epithelium releases “danger” molecules
- activate innate response (cytokines, acute phase proteins, inflammation)
- recruitment of immune cells to site
- more cytokines
- transport of foreign object to local lymph nodes
- lymphocyte proliferation and activation
- adaptive immune response
- antibodies &effector lymphocytes migrate and act at site of invasion systemically
- health
what are the characteristics of innate immunity
- fast (hours/days)
- short duration (days)
- no antigen recognition (non specific)
- receptors are broad and on a wide range of cells
- sometimes regulated, sometimes not
- no/minor amplification
- no self discrimination
- no memory
list the characteristics of adaptive immunity
- slow (takes days/weeks)
- long duration of activation (months/years)
- highly specific antigen recognition
- highly specific receptors (T and B cell receptors)
- highly regulated
- amplified
- self discriminate (important that they do)
- have memory
what are the functional characteristics of neutrophils
- short lived
- circulates in the blood (first leukocyte to migrate to areas of infection/inflammation to respond to cytokines
- phagocytic - englulfs and destroys bacteria through digestion with lysosomal enzymes
what are the functional characteristics of monocytes/macrophages
- mononuclear phagocytes - engulfs and destroys bacteria through digestion with lysosomal enzymes
- monocyte circulates in blood, differentiates to macrophages after migrating into tissue
- macrophages can act as antigen presenting cells with a central role in both innate and adaptive immunity
what are the functional characteristics of eosinophils
- circulates in blood
- protective role against parasites
what are the functional characteristics of basophils
- circulates in blood; least common leukocyte in normal blood smear
- responds to allergens
what are the functional characteristics of mast cells
- within the tissue, role in inflammation
- repsons to allergens (release histamine)
what are the functional characteristics of natural killer cells
- larger granular cytotoxic lymphocyte
- role in destruction of virus infected cells
what are the functional characteristics of dendritic cells
- specialised group of antigen presenting cells
- many subsets according to their tissue location
- dendrites can be long enough to reach accross tissue barriers
what are the functional characteristics of B lymphocytes
- express membrane bound receptors/antibodies
- central role in adaptive immunity
- can differentiate into plasma cells and release antibodies OR memory B cells
what are the functional characteristics of T lymphocytes
- cell mediated adaptive immune response
- recognize antigen displayed by major histocompatability complex (MHC)
- range of subsets, including T-helper cells, cytotoxoic T-cells