Dendritic Cells and Antigen Presentation

Questions and Answers

What is the primary function of antigen presenting cells?

To produce antibodies against pathogens

To regulate the inflammatory response

To recognize and eliminate pathogens from the body

To present antigens to other immune cells (correct)

What type of complex is involved in presenting antigens on the surface of antigen presenting cells?

MHC II complex (correct)

Complement protein complex

Antibody-antigen complex

MHC I complex

Which of the following cells is NOT a professional antigen presenting cell?

T cell (correct)

Macrophage

B cell

Dendritic cell

What is the term for the compatibility of tissues?

Histocompatibility Signup and view all the answers

What is the function of membrane-bound antibodies on B cells?

To recognize and attach to pathogens Signup and view all the answers

What type of cells can present antigens in conjunction with MHC II complexes?

All nucleated cells Signup and view all the answers

What happens to the pathogen after it is internalized by an antigen presenting cell?

It is degraded and processed Signup and view all the answers

What is the main difference between MHC I and MHC II complexes?

MHC I presents endogenous antigens, while MHC II presents exogenous antigens Signup and view all the answers

What happens to an activated T cell?

It differentiates into memory and effector T cells Signup and view all the answers

What is the primary function of effector T cells?

To recognize and kill infected cells or cancer cells Signup and view all the answers

What is the role of perforins in cytotoxic T cells?

To make little holes in the membrane of infected cells Signup and view all the answers

What is the difference between cytotoxic T cells and B cells?

Cytotoxic T cells kill infected cells, while B cells produce antibodies Signup and view all the answers

What is the purpose of granzymes in cytotoxic T cells?

To start mechanisms that lead to the death of infected cells Signup and view all the answers

What happens when a cytotoxic T cell binds to a cancer cell?

The cytotoxic T cell forces the cancer cell to kill itself Signup and view all the answers

Why are cytotoxic T cells important in fighting cancer?

They can recognize and kill cancer cells that present wacky proteins Signup and view all the answers

What is the significance of MHC class I complex in this context?

It helps cytotoxic T cells recognize and bind to infected cells Signup and view all the answers

What is the primary function of MHC I complex in the human body?

To present abnormal or foreign proteins to cytotoxic T cells Signup and view all the answers

Which type of cells in the human body do not have a nucleus?

Red blood cells Signup and view all the answers

What is the role of cytotoxic T cells in the immune response?

To eliminate infected or cancerous cells Signup and view all the answers

What is the purpose of MHC II complexes in the immune response?

To present antigens to helper T cells Signup and view all the answers

How do helper T cells and cytotoxic T cells recognize specific antigens?

Through a variable receptor that binds to specific antigens Signup and view all the answers

What is the mechanism that generates variability in the T cell receptors and membrane-bound antibodies?

Intentional shuffling of DNA during development Signup and view all the answers

Which type of cells can present abnormal or foreign proteins on their MHC I complex?

All nucleated cells except red blood cells Signup and view all the answers

What is the function of the variable portion of the T cell receptor?

To bind to specific antigens Signup and view all the answers

What is the outcome when a cytotoxic T cell recognizes an MHC I complex presenting abnormal or foreign proteins?

The cytotoxic T cell becomes activated and eliminates the infected or cancerous cell Signup and view all the answers

What is the difference between MHC I and MHC II complexes in terms of their interaction with T cells?

MHC I interacts with cytotoxic T cells, while MHC II interacts with helper T cells Signup and view all the answers

Study Notes

Antigen Presenting Cells

Dendritic cells are phagocytes and antigen presenting cells that digest pathogens, cut them up, and present the antigen on their surface with an MHC type II complex.
B cells also present antigens on their surface with an MHC II complex after internalizing and processing pathogens.

MHC Complexes

MHC stands for major histocompatibility complex, which means tissue compatibility.
MHC II complexes are found on professional antigen presenting cells, such as dendritic cells and B cells.
MHC I complexes are found on almost all nucleated cells in the human body, except for red blood cells.

MHC I Complex Function

MHC I complexes present pieces of viral or cancer proteins on the cell surface, signaling to cytotoxic T cells that the cell is infected or cancerous and needs to be killed.
This is a way for the cell to communicate with the immune system when it has been infected or has become cancerous.

T Cells

Helper T cells bond to MHC II complexes on antigen presenting cells, leading to activation and differentiation into effector and memory cells.
Cytotoxic T cells bond to MHC I complexes on infected or cancerous cells, leading to activation and differentiation into effector and memory cells.
T cell receptors have a non-variable portion and a variable portion that is specific to the combination of antigen and MHC complex.

Cytotoxic T Cell Function

Cytotoxic T cells are activated when they bond to MHC I complexes on infected or cancerous cells.
Activated cytotoxic T cells divide, differentiate, and release cytotoxins, such as perforins and granzymes, which kill the infected or cancerous cell.
Cytotoxic T cells are responsible for killing cells that have gone awry, such as cancer cells or virus-infected cells.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

This quiz covers the process of antigen presentation by dendritic cells, including phagocytosis and display of pathogens on their surface. Understand the role of dendritic cells as phagocytes and antigen-presenting cells.