case 17

Question 1

name an AIDS defining condition associated with a CD4+ count of <100mm3.

Answer 1

disseminated mycobacterium avium complex (MACS)

Question 2

which antibody class can cross the placenta to protect the newborn infant?

Answer 2

IgG

Question 3

what is the most common cause of fungal infection in the general population?

Answer 3

candida sp

Question 4

which organ is responsible for the negative selection of self recognising t lymphocytes?

Answer 4

thymus

Question 5

what needs to happen for t cell independent b cell activation to take place?

Answer 5

the b cell receptors need to be crosslinked

Question 6

which immunoglobulin has the major role in protection against helminths?

Answer 6

IgE

Question 7

how does chronic stress result in decreased immunity?

Answer 7

Cortisol release suppresses leukocyte transmigration, inhibiting leukocyte recruitment.

Question 8

HPA axis stimulation mainly promotes the release of what hormone?

Answer 8

cortisol

Question 9

what is the effect of cortisol on the blood vessels?

Answer 9

it stimulates adrenergic receptor expression, promoting vasoconstriction.

Question 10

what is generation time of a virus?

Answer 10

The period of time between a new host being exposed to a virus and the new host becoming infective.

Question 11

what is a PAMP and examples?

Answer 11

pathogen associated molecular patterns. found on surface of pathogens. eg bacteria: LTA (lipotechoic acid), LPS (lipopolysaccharide). viruses-viral coat proteins.