MIMM 214 Lecture 11: Linking Innate and Adaptive Immunity II: T Cells and MHC - The Basics

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ivorykangaroo940

7 Feb 2017

School

McGill University

Department

Microbiology & Immunology

Course

MIMM 214

Professor

Claire Trottier

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Document Summary

Apcs, mhc, & t cells: most adaptive immune responses require activation of t cells i. e. t cell-dependent responses. T cells can only recognize peptide fragments of the ag bound to self molecules of the major histocompatibility. These peptide-mhc complexes are expressed on the plasma membrane of self antigen-presenting cells (apc) Activation of cd4+ t cells: cd4+ t cells recognize ag on mhc ii, nature of the signal will tell the t cell what kind of t cell it will mature into. Activation of cd8+ t cells: cd8+ t cells recognize ag on mhc i. Type of lymphocytes: arising in the thymus from bone-marrow progenitors, key role in adaptive immunity. Identified by expression of t cell receptor (tcr) complexes on the cell surface. Cd8+ and cd4+ t cells: cd8+ t cells, become effector cytotoxic t lymphocytes (ctls, cd4+ helper t cells can be divided into distinct subsets, at least five distinct subsets.

Related Questions

Immunology worksheet help?

In people infected with human cytomegalovirus, class I MHC andb2-microglobulin are produced, but very little mature class I MHCis found at the cell surface. Inhibition of which of the followingmolecules by human cytomegalovirus may account for thisphenomenon?

A.	TAP
B.	Ii
C.	TCR
D.	CLIP
E.	RAG

Your chances of having the same MHC haplotype as your siblingare:

A.	1:2.
B.	1:4.
C.	1:16.
D.	1:8.
E.	1:1.

Which of the following is the BEST example of self-MHCrestriction of T cells?

A.	A T-cell clone is deleted when it binds too tightly to selfMHC.
B.	A T-cell clone responds more vigorously to a self-peptide thana foreign peptide.
C.	A T-cell clone recognizes foreign MHC.
D.	A T-cell clone only recognizes foreign peptides when presentedby self MHC.
E.	All of the above

MHC molecules:

A.	are conserved between individuals.
B.	bind repeating patterns found on pathogens.
C.	are recognized by T cells.
D.	are membrane-bound molecules found exclusively on T cells.
E.	are secreted by T cells and bind and neutralize antigen in theserum.

Tasmanian devils are a largely inbred population with littlediversity in the MHC. Which of the following would be a likelyoutcome of this?

A.	They would compensate for low diversity in the MHC with highdiversity in the TCR.
B.	They would compensate for low diversity in the MHC with highdiversity in the BCR.
C.	They would rely only on innate immune responses.
D.	They would be at higher risk of infection.
E.	All of the above

How many different MHC classical class I proteins does eachnucleated cell in a human heterozygous at the MHC locusexpress?

A.	Six
B.	Two
C.	Three
D.	One
E.	None. Only APC express class I.

MHC polymorphisms tend to cluster:

A.	in the peptide-binding groove.
B.	in the transmembrane domain.
C.	in the coreceptor contact residues.
D.	in the framework region.
E.	All of the above

A mutation that renders the MHC class II molecule DMnonfunctional would likely lead to:

A.	cells with no class II MHC.
B.	a deficiency in CD8⁺ T cells.
C.	cells with class II MHC only bound with CLIP.
D.	cells with class II MHC bound with a variety ofself-antigens.
E.	cells with no DO.

The human MHC locus is one of the most polymorphic regions ofthe genome. What does this mean?

A.	This region is regulated by many different mechanisms.
B.	Sequence variability is low in this region.
C.	There are many introns in this region.
D.	There are many different alleles of these genes.
E.	It has the most different genes.

10.

Which of the following is an example ofcross-presentation?

A.	An exogenous peptide being presented on MHC class II
B.	A B-cell antigen being presented to a T cell
C.	An endogenous peptide being presented on MHC class I
D.	An endogenous peptide being presented on MHC class II
E.	An exogenous peptide being presented on MHC class I

magentacamel430

Q.1 (a) Production of which of the following types of proteinsduring an innate immune response would directly lead to the lysisof a microbe?

- Membrane Attack Complex

- Perforin

- Immunoglobulin

- Interferon

Q 1. (b) Swelling due to bulk flow from the plasma into theinterstital fluid is the result of decreased protein permeabilityin the capillaries. (True or False?)

Q.1 (c) Both inflammation and fever result in an increase in thetemperature set point of the body. (True or False?)

Q.1 (d) Indicate which of the following statements describeClass I MHC molecules, describe Class II MHC molecules or decribeboth Class I MHC & Class II MHC molecules?

-This molecule is expressed on all nucleated cells.

- This molecule interacts with proteins expressed on the surfaceof Cytotoxic T cells.

- This molecule is expressed on the surface of Antigenpresenting cells.

- This molecule is important for activating helper T cells.

- This molecule is expressed on the surface of B cells

- This molecule binds to antigens that come from primarilyintracellular pathogens.

Q.1 (e) What type of B cell does not secrete many antibodiesduring a primary immune response, but is very important for asecondary immune response?

Q.1 (f)If an individual failed to develop any maturelymphocytes, they would have lessened innate responses to infectionand lessened adaptive responses to infection. (True or False?)

Q.1 (g) Which of the following statements about the late stagesof HIV infection/AIDS are true? Choose all of the correctanswers.

		A person in the late stages of AIDS is more susceptible toinfection with bacteria, fungi and viruses than a person in theasymptomatic stage of HIV infection.
		The number of CD4-expressing T cells in the blood is high duringthe late stages of HIV infection
		The number of Killer T cells in the blood can be high during thelate stages of HIV infection.
		Innate immune responses may be weakened during the late stagesof HIV infection because of the weakened adaptive responses duringthese stages.