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File:IPLab10Crypto12.jpg|This is a touch prep of fresh lung tissue that was allowed to air dry and then stained to show the mucopolysaccharide capsule around the cryptococcal organisms (arrows).
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== Study Questions ==
* <spoiler text="How is Cryptococcus neoformans usually transmitted to man?">Cryptococcus neoformans is present in the soil and in bird (particularly pigeon) droppings.
The organism infects humans when it is inhaled.</spoiler>
* <spoiler text="Who is susceptible to infection with C. neoformans?">Normal healthy people can get cryptococcal meningoencephalitis but cryptococcal infections are more common in individuals
(1) who receive high-dose corticosteroids and/or
(2) who have AIDS, leukemia, lymphoma, systemic lupus erythematosus,
Hodgkin’s disease, sarcoidosis, or transplant patients.</spoiler>
* <spoiler text="What virulence factors facilitate infection by C. neoformans?">Three properties of Cryptococcus neoformans are associated with virulence:
(1) the capsular polysaccharide;
(2) resistance to killing by alveolar macrophages; and
(3) production of phenoloxidase an enzyme that consumes host epinephrine in the synthesis of fungal melanin and thus protects the fungi from the epinephrine oxidative system present in the host nervous system.
It is thought that one reason why Cryptococcus neoformans preferentially infects the brain may be because the CSF lacks alternative pathway complement components (present in serum) that bind to the carbohydrate capsule and facilitate phagocytosis and killing by polymorphonuclear cells.</spoiler>
{{IPLab 10}}
[[Category: IPLab:Lab 10]]
