Lecture 5 Quiz: B Cells 1 Flashcards
Which of the statements below describe a similarity between T and B cell receptors? a. They both have more than one binding site. b. Interaction of the receptor variable region with a specific antigen is fundamental for lymphocyte activation. c. Their structure include alpha and beta chains. d. They can be secreted as antibodies.
Interaction of the receptor variable region with a specific antigen is fundamental for lymphocyte activation
Which of the following immune cells is capable of secreting large amounts of antibody?
Plasma cells –plasma cells are B cells specialised in antibody production.
Which of the statements below correctly describes B cells and plasma cells? a. Both are lymphocytes showing a high level of B cell receptor expression on their surface. b. Both show little cytoplasm and a round nucleus. c. Both show a large cytoplasm containing rough ER. d. Plasma cells are differentiated B cells with the primary role of secreting antibodies.
Plasma cells are differentiated B cells with the primary role of secreting antibodies. upon binding of antigen to the B cell receptor, B cells proliferate and differentiate into their effector form known as plasma cells which produce and secrete large quantities of antibodies specific to the given antigen.
Complete the following sentence. The antigen binding site of an antibody is located…..
between the variable region of the heavy and light chains. the area between the variable domains of the heavy and light chains is unique to each antibody and encodes the antigen binding site.
What is the major structural difference between B cell antigen receptor (BCRs) and secreted antibody?
Secreted antibodies lack a cytoplasmic tail. secreted antibodies have a tail piece replacing the hydrophobic transmembrane region and cytoplasmic tail of the BCR.
What is the difference between the recombination of heavy and light chain variable regions?
The resulting heavy chain is comprised of a variable, a diversity and a joining segment whereas the light chain lacks a diversity segment. — both heavy and light chain recombination rely on RAG1 and 2.
Which of the components listed below forms the B cell antigen receptor?
a. IgG antibody. b. Ig-alpha. c. Ig-beta. BCRs comprise both the antibody and the Ig-alpha and Ig-beta complex.
Complete the following sentence. Initiation of the germinal centre reaction is mediated by the………
activation of B cells by CD40 ligation. CD40 ligation is required for the initiation of the germinal centre reaction.
Complete the following sentence. Proliferation and differentiation of B cells can be enhanced by thymus independent antigens including……
a. interaction of PAMPs with corresponding TLRs activating downstream signalling which in turn stimulate B cell proliferation and differentiation. b. recognition of opsonised pathogens by binding of the complement component C3d to the B cell co-receptor CD21 which enhance BCR signalling.
Complete the following sentence. Somatic hypermutation consists of the……..
introduction of point mutations into the rearranged VL & VH genes in order to increase antigen affinity. — in germinal centres within lymph nodes, effector CD4 T cells activate antigen specific B cells, which migrate to follicles for further proliferation. The enzyme AID mediates the introduction of point mutations that introduce variation into the B cell receptor. B cells expressing receptors with increased antigen affinity are selected for survival.
