C1.2 NK continued

Question 1

what does short term exposure of IL-12 result in

Answer 1

NK cells release IFNy &* TNFa & high cytotoxicity activity (effector NK cells) in LN: promotes Th1
(IL12 = effector: cytotoxity (IFNy/TFNa –> quiescent NK cells)

Question 2

what does exposure of IL-18 result in

Answer 2

(from DC cells) promotes development of CD56+/CD83+/CCR7+/CD25+ cells (helper NK cells) – migratory NK cells – favor Th1 response
(IL-18 = helper: no cytotoxity (high IFNy release –> migratory phenotype Nk cells)

Question 3

what are the 3 main types of NK cells

Answer 3

1. Killer immunoglobulin–like receptor (KIR)
2. Heterodimeric C–lectin receptors
3. Natural cytotoxicity receptors

Question 4

name cell highly expressed in effector NK cells

Answer 4

NKp30 & NKp46 (NKp30+NKp46+NK bright clones)

Question 5

Define DC editing

Answer 5

NK cell involved in controlling quality and quantity of DC - eliminate DCs at immature stage, and therefore bona fide tolerogenic DCs - NKp30 receptor involved

Question 6

what happens to patients with a genetic mutation in beta2 integrin (CD18)

Answer 6

have NK cells which are less cytotoxic

- No CD18: Cant mediate in antibody dependent cytotoxicity

Question 7

define hyper-IgM syndrome

Answer 7

due to a mutation in the CD40 ligand gene resulted in natural killer (NK) cell deficiency
↓ levels of IgG in the blood & normal or elevated levels of IgM
Patients have no CD56+ or CD16+ cells and no NK activity

Question 8

define Hermansky-Pudlak syndrome type 2

Answer 8

an autosomal recessive disease characterized by partial albinism
have NK cells with low perforin levels and NK cells have low cytotoxic activity