Immunology 316 weekly quizzes #4

The protein molecules that display (i.e., present) lipids instead of the classical peptides are called:

CD1 proteins

When a TCR-peptide-MHC complex forms, the upregulation of CD 40L on the surface of the helper T cell (check all that apply):

Causes the T cell to be more able to activate B cell Causes the APC to produce more CD40 proteins on its surface Improves the lifespan of the APC

On mature T cells, CD4 and CD8 co-receptors (check all that apply):

Clip onto the MHC molecule after the ab receptor has bound to its cognate antigen Strengthen the signal sent by TCRs Help to stabilize the TCR-antigen-MHC interaction

To be activated, a naïve helper T cell requires formation of the TCR-antigen-MHC complex and:

Co-stimulation by the APC displaying the antigen

HLA-DM has which functions

Competes with other peptides for binging to class II MHC molecules

The idea that an exogenous antigen could be displayed by a class I MHC molecule is called:

Cross presentation

Proteins displayed on class I MHC molecules are:

Endogenous proteins

The invariant chain-CLIP-HLA-DM-class II MHC pathway displays:

Exogenous proteins

The location at which an APC and a T cell contact one another and adhesion molecules strengthen the connection is called the:

Immunological synapse

The peptide that occupies the class II MHC groove to serve as a chaperone, thereby preventing endogenous proteins in the endoplasmic reticulum from binding is the:

Invariant chain or CLIP

The proteins responsible for immediate rejection of an organ transplantation are:

MHC molecules

Which statement about TCRs is false:

Most mature T cells circulating in the body have gd receptors on their surface.

Proteins that have many different variants across the human population are called:

Polymorphic

The component of human cells that destroy proteins is called the:

Proteasome

The primary role of a dendritic cell is to:

Serve as sentinels, collect information on invaders, and report that information by traveling to lymph nodes

Peptides fragments in the cytoplasm of human cells are taken to the endoplasmic reticulum by:

TAP transporters Class I MHC molecules

In traditional T cells, the TCR signaling requires that:

TCRs cluster near each other on the surface of a T cell

Dendritic cells can become activated by (check all that apply):

TNF secreted by macrophages and neutrophils Pattern-recognition receptors that are on the surface of dendritic cells that recognize a pathogen directly Compounds secreted by cells being killed by a pathogen

Activated B cells have what advantage over other APCs? (check all that apply)

They are able to concentrate antigen to make presentation more efficient They can process antigen and display in on a class II MHC molecule much more quickly than other cells

Activated B cells have what advantage over other APCs? (check all that apply)

They can process antigen and display in on a class II MHC molecule much more quickly than other cells They are able to concentrate antigen to make presentation more efficient

An individual class I MHC molecule can bind to type(s) of peptides; an individual antibody can bind to type(s) of peptides.

a variety of exactly one

Macrophages and dendritic cells both present antigen most efficiently when they have been activated by other signals suggesting an invader is dangerous. They differ in that....

activated macrophages can kill cells directly and do not travel , and activated dendritic cells cannot kill cells directly and can travel .

Each person expresses up to how many different class I MHC molecules:

6

Which of the following are antigen presenting cells? (check all that apply)

Activated dendritic cells Activated B cells Activated macrophages

Antigens that are presented by class I MHC molecules 8-9 amino acids long, and antigens that are presented by class II MHC molecules 13-25 amino acids long.

Answer 1: 8-9 Answer 2: 13-25

Put the following events in the activation of a helper T cell in order from beginning to end:

Answer 1: A T cell binds to the cognate antigen being presented by a class II MHC molecule Answer 2: The T cell's CD4 co-receptors clip into the class II MHC molecule of the APC, stabilizing the interaction between the T cell and APC. Answer 3: The expression of adhesion molecules on the surface of the T cell is upregulated. Answer 4: The expression of CD40L on the surface of the T cell are upregulated, increasing the ability to bind to the APC's CD40 proteins, which results in production of co-stimulatory molecules like B7 on the surface of the APC. Answer 5: The T cell and APC separate. Answer 6: The Th cells proliferate

Put the following events in the dendritic cell life cycle in order from beginning to end:

Answer 1: Dendritic cells in tissue express low levels of MHC molecules and some B7 protein Answer 2: Dendritic cells are activated by TNF, chemical signals from dying cells, or recognition of pathogens directly by PRRs such as Toll-like receptors Answer 3: Dendritic cells increase phagocytosis to sample pathogens Answer 4: Dendritic cells quit phagocytosis and increase expression of class I and class II MHC molecules while traveling to the lymph node

Class I MHC molecules specialize in showcasing what is happening Inside a cell, and class II MHC molecules specialize in showcasing what is happening Outside of a cell.

Answer 1: Inside Answer 2: Outside

can only recognize their cognate antigens if they are presented, but cells can recognize their cognate antigens if they are not presented (i.e., soluble).

Answer 1: T cells Answer 2: B cells

Because helper T cells help activate other immune cells , they need to inspect cells that . Therefore, helper T cells inspect antigens that are presented on , and helper T cells use as the co-receptor.

Answer 1: help activate other immune cells Answer 2: present antigens of invaders Answer 3: class II MHC molecules Answer 4: CD4

Cells that can display both class I and class II MHC molecules and can provide co-stimulatory signals are called:

Antigen presenting cells

To become activated, which kind of cells need to bind to their cognate antigens and receive a co-stimulatory signal? (check all that apply)

B and T cells

A class I MHC molecule is made up of (c

B2-microglobulin HLA protein

The two-step activation process for a helper T cell includes formation of the TRC-antigen-MHC complex and co-stimulation by the APC that presents the antigen. This ensures that:

Both the T cell and the APC agree that there is an invasion