JMacSharry lecture II

Question 1

name and describe three components of the inflammatory response to fungal respiratory infection

Answer 1

1. recognition: PRR, TLRs, NLRs on epithelia and phagocytes (macrophages, neutrophils, DCs, mast cells)
2. recruitment: cytokine secretion to attract leukocytes and plasma components, neutrophils
3. resolution: successful acute response eliminates infection, resolution and repair by tissue resident macrophages

Question 2

what does neutrophil degranulation release

Answer 2

defensins, AMPs, histamine, prostaglandins, ROS, proteinase, cathepsin, elastase.

Question 3

name virulence factors of cyrcryptococcus spp.

Answer 3

capsid and melanin

Question 4

by what age do humans normally develop Abs to C. neoformans

Answer 4

normally develop Ab to this by school age

Question 5

what can cryptococcus spp cause in IC patients>

Answer 5

it can cause pneumonia

Question 6

what can cryptococcus spp cause in non-immunocompromised patients

Answer 6

an asymptomatic latent infection

Question 7

what is C. neoformans typically abundant in?

Answer 7

avian excreta

Question 8

how do naturally acquired cases of cryptococcosis occur?

Answer 8

by inhalation of fungal cells from the environment.

Question 9

what can happen after development of latent infection

Answer 9

dissemination of latent infection, most notably to the CNS.

Question 10

What happens when cryptococcosis reaches the CNS?

Answer 10

overwhelming infection of the meninges and brain tissue, often accompanied by increase in intracranial pressure if there is no treatment.

Question 11

cryptococci tend to be _ _. driving much lower levels of _-inflammatory cytokines

Answer 11

immunologically inert, pro.

Question 12

name the complex carbohydrates which form the cryptococcal capsule?

Answer 12

glucuronoxylomannan (GXM) and galactoxylomannan (GalXM)

Question 13

when GalXM and GXM are shed, what TF is inhibited and causes what?

Answer 13

inhibition of NF-kB to dampen levels of pro-inflammatory cytokines

Question 14

cryptococcus spp block DC maturation, how?

Answer 14

by reducing both MHC class II-dependent antigen presentation and inhibiting the production of proinflammatory cytokines IL-12 and IL-23

Question 15

mainly _ mycoses in immunocompromised

Answer 15

opportunistic

Question 16

yeast example

Answer 16

candida albicans/candida spp yeast-like
cryptococcus neoformans yeast-like, bird faeces

Question 17

mould example

Answer 17

aspergillus fumigatus

Question 18

cryptococcus neoformans is found commonly from?

Answer 18

pigeon droppings

Question 19

where does cryptococcus neoformans usually infect?

Answer 19

respiratory tract

Question 20

how does cryptococcus neoformans typically present, esp. in immunocompromised

Answer 20

usually presents as Meningitis in IC (T cell deficient like HIV-AIDS)

Question 21

how is cryptococcus neoformas typically diagnoses

Answer 21

lung wash or lung biopsy

Question 22

describe the pathogenesis of cryptococcus neoformans?

Answer 22

alter M1 and Th1 pathways from their typical inflammtory pathway to something more typcial of the allergy pathway of Th2 and M2

Question 23

why are cryptococcus neoformans so good at avoiding macrophages

Answer 23

this is because they grow among amoeba which macrophages have descended from

Question 24

aspergillus fumigatus, describe

Answer 24

spore-forming mould, ubiquitous, opportunistic

Question 25

how does aspergillus fumigatus infect?

Answer 25

inhaled spores

Question 26

pulmonary aspergillosis

Answer 26

allergic form, allergic bronchopulmonary aspergillosis (ABPA) causing wheeze, cough, eosinophilia.

Question 27

aspergilloma

Answer 27

inhaled spores enter pre-existing cavity (from previous TB infection), can be asymptomatic, cough, haeoptysis, dyspnoea, weight loss, fatigue, can also involve sinuses and ear canal