true or false? in the absence of innate immunity, there is also no adaptive immunity,
what are the anatomical barriers of the innate immune system?
the skin, gut, lungs, eyes/nose
what are the cellular components of the innate immune system?
neutrophils and macrophages, eosinophils, and NK cells
what are the chemical components of the innate immune system?
cytokines and chemokines, leukotriens and prostaglandins, complement proteins, protease inhibitors, acute phase proteins
what are the two types of epithelium that make up the surface of the human body?
1. skin (provides just a physical barrier
2. mucosal surfaces (epithelial linings of the respiratory, GI, and urogenital tracts; provide communication between body and environment; secrete mucus)
what is mucus?
a thick fluid covering mucosal epithelium, and preventing pathogens from adhering to the epithelium; contains defensins, lysozyme, and protease inhibitors
what are commensal species?
nonpathogenic microorganisms that protect epithelium by competing with pathogens for nutrients and attachment sites
describe what macrophages are
tissue macrophages and newly recruited monocytes, which differentiate into macrophages; reside in tissues; usually the first cells that come into contact with the pathogen. Function in phagocytosis and intracellular killing of microorganism. Contribute to tissue repair and act as antigen-presenting cells, which are required for the induction of specific immune responses.
neutrophils are the first cells that are recruited to the site of infection or injury. They phagocytose invading organisms and kill them intracellularly. In addition, they contribute to tissue damage that occurs during inflammation.
describe natural killer cells
they nonspecifically kill virus-infected and tumor cells. These cells are not part of the inflammatory response but they are important in nonspecific immunity to viral infections and tumor surveillance.
they have proteins in granules that are effective in killing certain parasites.
where are monocytes found?
monocytes circulate in the blood
macrophages differentiate from what?
what are the two things that an activated macrophage does?
1. releases pro-inflammatory cytokines (IL-1, IL-8, and TNF) that attract neutrophils from circulation (to help the macrophages with phagocytosis).
2. presents digested pathogen as MHC class II molecules to naive T cells to activate adaptive immunity
how long do neutrophils usually live for?
what is neutrophil extravasation?
the process of neutrophils leaving capillaries
what happens to the structure of blood vessels during the inflammatory response?
during inflammatory response, the endothelial cells that make up the walls of the blood vessels contract. Since these blood vessels get larger in diameter as a result of this, the process is called vasodilation. Vasodilation increases the space between the endothelial cells resulting in increased capillary permeability. consequently neutrophils can squeeze through the spaces between the endothelial cells
true or false? eosinophils and basophils are involved in allergic reactions
which leukocyte is least abundant in the body?
what are prostaglandins?
they are chemicals that increase vasodilation and serve as chemoattractants for neutrophils.
what are leukotrienes?
they are chemicals that increase smooth muscle contraction and they serve as a chemoattractant for neutrophils