Cell Mediated Immunity and Humoral Responses II

Question 1

AICD

Answer 1

Activation induced cell death

Question 2

What are the primary functions of CD4+ T cells?

Answer 2

To activate APCs (macrophages and dendritic cells), to produce cytokines, and to activate B cells

Question 3

Do cytokines tend to exhibit effects locally or globally?

Answer 3

Locally

Question 4

How many chains does the IL2 receptor have and what are the chains? Include whether the chain is constitutively or transiently expressed and its effect on IL-2 affinity

Answer 4

Gamma chain, Beta chain, and Alpha chain. BG are constitutive, low IL-2 affinity. Alpha (aka CD25) is transient and has high IL-2 affinity

Question 5

What are the 5 major types of CD4+ T cells?

Answer 5

TH1-type, TH2-type, TH17-type, TH0, and Treg cells

Question 6

TH1-type cells (give primary role, cytokines produced, induction, TF which produces differentiation, and any cross-regulation)

Answer 6

Inflammation, produces IL-2, IL-3, IFNg, induced by IL-12 and IFNg, TF is T-bet, and produces IFNg to inhibit TH2-type cells

Question 7

TH2-type cells (give primary role, cytokines produced, induction, TF which produces differentiation, and any cross-regulation)

Answer 7

Humoral response, produces IL-3, IL-4, IL-10, induced by IL-4, TF is GATA-3, produces IL-4 to promote TH2 at expense of TH1 and IL-10 to inhibit TH1

Question 8

TH-17 type cells (give primary role, cytokines produced, induction, TF which produces differentiation, and any cross-regulation)

Answer 8

Recruitment of neutrophils and monocytes (chronic inflammation), produces IL-17, 21, 22, 6, and CXCL8 (neutrophil attractant), differentiation by IL-6, 1, 23, and TGFB, TF is RORgt

Question 9

Where are TH17-type cells predominantly found and what human diseases are they involved in?

Answer 9

Found in lung, other mucosal surfaces, tumors, sites of chronic inflammation. Involved in psoriasis, rh arthritis, IBS, and asthma

Question 10

What type of cells are thought to be precursors to TH1 and TH2 type cells?

Answer 10

TH0 cells

Question 11

Treg cells (give primary role, cytokines produced, induction, TF which produces differentiation, and any cross-regulation)

Answer 11

Inhibition of anti-self responses, produce IL-10 and TGFB, requires IL-2 and can be induced by TGFB, TF is FoxP3

Question 12

What are the two main functions of CD8+ T cells?

Answer 12

Cytotoxicity and cytokine production

Question 13

What cytokine is best known for inhibiting viral replication without killing the infected cell?

Answer 13

IFNg

Question 14

Which interleukin attracts neutrophils to a site of inflammation?

Answer 14

IL-17

Question 15

What are two ways which activation induced cell death (AICD) might be achieved?

Answer 15

Fas receptor and Fas-Ligand interaction on same cell or neightboring cells, or failure to receive anti-apoptotic signals

Question 16

Autoimmune Lymphoproliferative Syndrome

Answer 16

ALPS. Defective expression of Fas or Fas-L which results in lympho-accumulation and autoimmune symptoms (no AICD)

Question 17

What are two cytokines that regulatory T cells might emit to suppress immune responses?

Answer 17

IL-10 or TGFB

Question 18

Immunodysregulation-polyendocrinopathy-enteropathy X-linked syndromes

Answer 18

IPEX. A mutation in FoxP3 (a TF) which inhibits development of Tregs