Immunology: Chapter 11 Quiz

_____ accounts for the production of different isoforms of the CD45 protein observed in naive, effector, and memory T cells.

Alternative splicing

True or false: The CD45RA isoform is associated with stronger signals in response to antigen.

False

Which of the following statements is incorrect regarding memory B cells?

Memory B cells express lower levels of MHC class II and B7 than do naive B cells.

During a secondary immune response, high-affinity IgG antibodies are produced. Which of the following best explains why low-affinity IgM antibodies are not made?

Naive pathogen-specific B cells are suppressed by negative signaling through FcγRIIB1.

In which ways do memory B cells active in a secondary immune response differ from the naive B-cell population activated in a primary immune response? (Select all that apply.)

The antibody produced is of higher affinity in a secondary immune response, the level of somatic hypermutation is higher in a secondary immune response, and memory B cells express higher levels of MHC class II molecules

Which of the following characterizes immunological memory? (Select all that apply.)

The host retains the capacity to mount a secondary immune response, the host retains the ability to respond to pathogen many years after primary exposure, memory B cells produce higher-affinity antibody than naive B cells

Memory B cells differ from memory T cells in the following ways. (Select all that apply.)

The suppress naive antigen-specific lymphocytes during secondary immune responses and they recirculate only through secondary lymphoid organs.

"Original antigenic sin" is best described as a phenomenon in which _____.

a highly mutable virus gradually escapes from immunological memory and interferes with compensatory immune responses.

What would be the outcome if a naive B cell were to bind to pathogen coated with specific antibody made by an effector B cell in a primary immune response using FcγRIIB1, and simultaneously bind to the same pathogen using its B-cell receptor?

a negative signal leading to inhibition of the production of low-affinity IgM antibodies

By which processes are fetal erythrocytes destroyed in hemolytic anemia of the newborn?

clearance of antibody-coated erythrocytes by macrophages in the fetal spleen

The production of CD45RO results from the removal of _____ during _____ processing.

exons A, B, and C; post-transcriptional

RhoGAM is administered to pregnant RhD- women so as to _____. (Select all that apply.)

inhibit a primary immune response to RhD antigen and prevent hemolytic anemia of the newborn

The efficiency and specificity of adaptive immune defenses and immunological memory improve each time a particular pathogen is encountered because _____.

of affinity maturation

When a naive B cell binds to an IgG:antigen complex on its cell surface using FcγRIIB1, while simultaneously binding to the same antigen using membrane-bound IgM, _____.

the B cell becomes anergic