Innate and adaptive immunity (year 2) Flashcards
what are the forms of innate immunity?
mechanical physiological molecular cellular microbiological environmental
describe the innate response in terms of speed, memory and specificity
fast
no memory
non-specific
give some examples of mechanical innate immunity
skin/fur
cilia and air movement in respiratory tract
liquid flushing - tears, urine, diarrhoea
mucus
what is the job of mechanical innate systems?
prevent entry of pathogens into the body systems
give some examples of innate physiological barriers
pH changes and extremes
pyrexia
describe the cellular defences of the innate system
macrophages - phagocytose microorganisms
neutrophils - phagocytic and degranulate
mast cells/basophils/eosinophils - have antibody receptors and increase vascular permeability leading to fluid accumulation and inflammation
what are the aspects of the molecular defence system associated with the innate immune system?
defensins, lysozyme, sweat gland secretions, myeloperoxidase system, acute phase proteins, complement, interferons
what do defensins do and where are they found?
small proteins found in many cells and tissues especially phagocytes and epithelial cells. they are active against bacteria, fungi and viruses and cause cell membrane rupture
what are lysozymes?
family of enzymes that attack peptidoglycan cell walls of bacteria
where are the sites of action of lysozymes?
cellular - cytoplasmic granules of macrophages
secretions - tears, saliva, mucus
sebum - from sebaceous glands
how do lysozymes and sweat gland secretions protect the body?
create an inhospitable environment and make it harder for pathogens to stick to the skin of animals
what is myeloperodidase?
enzyme found in lysosomes in granulocytes and macrophages that kills bacteria and other pathogens by producing toxic hypochlorite
give an example of microbiological defence in the innate system
commensal bacteria
where are commensal bacteria found and what role do they play in the innate immune system?
mucosal surfaces (especially GI, skin, respiratory) - prevent attachment of pathogenic bacteria
describe how the enrolment and management contribute to the innate immune system
via husbandry for example diet, temperature and humidity
