Immunoregulation

Question 1

Immunoregulation
Function:

Answer 1

Enhance immunity

Eliminate foreign antigens

Diminish harm to self tissues

Question 2

Define Immunoregulation ??

Answer 2

.A balance between activation & suppression of effector cells to achieve an efficient IR without damaging the host

Question 3

Immune response must be regulated at the following level:

Answer 3

Response must be only to foreign antigen and no response to self antigen

Which type of immune response must be activated

Response termination…… Homeostasis

Question 4

Important regulatory decisions determine the
branch of the immune system to be activated, the……….. of the response, and its………..

Answer 4

intensity/duration

Question 5

Involved in initiating immune response
•Involved in turning off immune response
•Some serve as direct effector molecules (e.g., TNFα) all are functions of…….

Answer 5

Cytokines

Question 6

At the end of immune responses􏰂immune system return to its basal resting state, most of the cells die by apoptosis as they deprived from essential survival………..

Answer 6

Stimuli

Question 7

How does antigens regulate IR??

Answer 7

(Major regulatory factor)
By their properties (chemical properties,large insoluble)

Dosage→↑dose-→tolerance

Inoculation ways →S.c or intradermal ✓ IM →th2

Question 8

How does the antibodies regulate the IR????

Answer 8

1-(ab blocking)the ab doesn’t let the b-cells To adhere to the Ag by Bcr so the b-cells will get terminated

2- (cross-linking)the Ag is holding the ab & bcr

Question 9

Role of complement & regulation of complement activation

Complement active fragment→……………………………/…,…,….→ bind w MQ opsonization

Complement regulatory protein……….

Answer 9

Inactivate spontaneously/ c3b,c4b,ic3b
Negative

Question 10

Cytokines and Immunoregulation
It——-&……..

Answer 10

Regulate & inhibit

Question 11

Positive regulation

IFN-gam、TNF-α→…………..

IL-2、IL-4、IL-5、IL-6→………,……..

IL-12、TNF-α→………….

Negative regulation

Il-10、TGF-B→…….,……,………

Answer 11

Promote MHC on APC

PROMOTE, T-Cell+B-Cells activation proliferation, differentiation

Activate CTL

↓MQ,Tcells +CKs

Question 12

Th1 ↑(cmir)→…………………..

Th2 ↑(hmir)→…………………

Answer 12

autoimmune disease
type 1 hypersensitivity +SLE

Question 13

…………,………..T-reg cell
Secrete cks& inhibit——

Also can affect the activation and function of………. immune cells

Can be used for immunotherapy of chronic inflammatory or autoimmune disease

Answer 13

CD4+, CD25+
T cells
innate

Question 14

Function of Treg cells

Answer 14

Homeostatic control
– Prevent potential outgrowth of auto-reactive T cells
• Damage control
– Limit the tissue injury during inflammation caused by infection/autoimmune/transplantation
• Tolerance
– Stabilized tolerance during the final stage of inflammation

Question 15

During the immune response:

Answer 15

Antiapoptic proteins
•Co –stimulator
• Survival signals
•Cytokines

Question 16

Apoptosis in immune response

AICD (Activation Induced Cell Death)
Th cells express both…… and…….. , may
kill either themselves

Answer 16

Fas/FasL

Question 17

Two-signal requirement for T lymphocyte activation :

Answer 17

Signal 1: antigen recognition 􏰂 Ensure that the immune response is antigen-specific

Signal 2: Costimulation (soluble cytokines& cell surface mols)

Question 18

co-signal molecule on T cell surface
CD28&raquo_space;>B7 co-………..
CTLA-4»>B7 co-…………

Answer 18

stimulator

inhibitory molecule

Question 19

How do T cells choose between CD28 and CTLA-4?

Answer 19

B7 on APCs engages CD28 early,
CTLA-4 late in Tcell responses

Level of B7 expression on APCs: low levels favor CTLA-4 engagement

Question 20

Regulation of cell apoptosis

FasL/Fas pathway mediated…….. 􏰉activated T cell clone apoptosis

Answer 20

AICD

Question 21

Regulation at individual level

Neuroendocrine immune system regulation

Answer 21

􏰊Glucocorticoids and androgens:inhibit IR

􏰊Growth hormone、thyroxine, insulin and
estrogen : augment IR