Exam 16: Antigen-Processing

Match the description in questions with the lettered item (A-I)related to antigen-presentation pathways. -A protein that binds to newly synthesized class II MHC molecules in the endoplasmic reticulum (ER),which blocks the peptide binding site and directs transport of the class II MHC molecule to endosomes.

The cell type shown below is found between follicles in lymph nodes and expresses B7-1,B7-2,and class II MHC.What type of cell is this?

Antigen-presenting cells (APCs)perform which of the following functions in adaptive immune responses?

Match the description in questions with the lettered item (A-I)related to antigen-presentation pathways. -Site of peptide loading of class I MHC molecules

Many vaccines now include highly purified,recombinant,or synthetic peptide antigens.Given alone,the antigens in these vaccines would be less immunogenic than vaccines containing intact killed or live microbes.Adjuvants are substances added to purified protein or peptide vaccines to enhance their ability to elicit T cell immune responses.Which of the following statements about these adjuvants is NOT correct?

Match the description in questions with the lettered item (A-I)related to antigen-presentation pathways. -Required for proteolytic generation of class I MHC-binding peptides

A helper T cell response to a protein antigen requires the participation of antigen-presenting cells that express which of the following types of molecules?

Match the description in questions with the lettered item (A-I)related to antigen-presentation pathways. -Site of proteolysis of antigens in the class II MHC pathway

A child who suffers from a persistent viral infection is found to have a deficiency in lymphocyte production and very few T and B cells.Other bone marrow-derived cells are produced in normal numbers,and MHC molecule expression on cells appears normal.Transfusion of mature T cells from an unrelated donor who had recovered from a previous infection by the same virus would not be expected to help the child clear his infection.Which one of the following is a reasonable explanation for why this therapeutic approach would fail?

Match the description in questions with the lettered item (A-I)related to antigen-presentation pathways. -The molecule that binds to the final product of the class II antigen-pocessing pathway