Fungal Immunity Flashcards
Which phylum is the most common in causing human disease?
ascomyota
What is the appearance of aspergillus?
flowering- stalk with spores which germinate and form hyphae
Where does the cryptococcus neoformans that we breathe in all the time from?
trees and pigeons
Who gets cryptococcus neoformans?
people with defects in T cells e.g HIV/AIDs
How does cryptococcus avoid phagocytosis?
forms a capsule
Why does candida cause endophthalmitis?
gets stuck in microcapillaries
What are the opsonins in fungal infections?
pentraxin 3 and MBL
What type of T cells are protective in fungal infection?
Th1 and Th17
What are the 2 forms of candida?
yeast (circular cell form) and hyphal forms
Why does transitions between different forms of fungus cause problems in the host?
causes switching between protective (Th1/Th17) and non-protective (Th2) responses
What is aspergillus species inhaled as?
conidia
What form does aspergillus invade tissues as?
hyphae
What is the classic DAMP signalling in fungal recognition?
S100B-RAGE
What receptors are involved in the phagocytosis of fungi?
CTLRs, not TLRs
What 2 pathways are downstream of dectin-1 signalling?
inflammasome and NFkB
What does dectin-1 deficiency result in?
reduced IL-6 production and binding to candida–mucocutaneous fungal infections
What is required for NFkB activation by dectin-1?
CARD9
What does homozygous CARD9 mutation result in?
chronic mucocutaneous candidiasis
What cytokine is CARD9 required for production in response to beta-glucans?
TNFa
How is CARD9 invovled in T cell differentiation?
required for T cell Th17 differentiation
Deficiency in what TLR results in greater susceptibility to aspergillosis?
TLR4
What effect does plasminogen have aspergillosis defense?
directly binds to aspergillus conidia and decreases susceptibility
How are macrophage depleted mice affected with aspergillus fumigatus?
not any more susceptible
Which cells are most important in defense against invasive aspergillosis?
neutrophils - as without have no ability to clear the infection