Pathology 3240A Chapter 10: Immunity and Immune Disorders - Howlett
Document Summary
Bod(cid:455)"s defe(cid:374)se (cid:373)e(cid:272)ha(cid:374)is(cid:373) agai(cid:374)st pathogenic microorganism, their products (toxins), as well as tumour cells: pathogens include viruses, bacteria, mycobacteria, parasites, and fungi. Two major components: the innate immune system and the adaptive immune system: innate immunity. Born with it (adaptive immunity takes a while to develop in newborns, which is why maternal antibodies are provided via breast feeding) Activation of innate immunity does not require previous exposure to an antigen/stimulus. An innate immunity is found in nearly all forms of life (adaptive immunity is found only in jawed vertebrates) Does not require previous exposure to an offending agent (antigen) Mechanical barriers include skin, epithelial barrier and mucosa surfaces of gi and respiratory tract. Chemical barriers include enzymes in saliva, vaginal secretions, and tears. Biological barriers include bacterial flora in different organs. Phagocytes cells with the ability to recognize and engulf microorganisms. Include neutrophils (rapidly recruited to site of infection), and macrophages (already present)