IMB 401 MODULE #5 EXAM REVIEW SOLVED
What's BCR? - correct answer BCR (B Cell Receptor) is the antigen receptor on the
surface of B cells. It allows B cells to recognize and bind to specific antigens.
What types of antigens interact with BCR? - correct answer B cell antigens are
recognized as whole, intact, free antigens, unlike T cell antigens, which must be
processed and presented on MHC molecules.
How are B cells activated and what molecular interactions are required? - correct
answer B cell activation requires TWO signals:
Signal 1: Antigen binds to the BCR.
Signal 2: Either through interactions with helper T cells (for thymus-dependent antigens)
or through pattern recognition receptors (for thymus-independent antigens).
Additional co-receptors like CD21 and CD19 enhance signaling.
What's the role of complement in B cell activation? - correct answer Complement
components, such as c3b, interact with complement receptors (CR1, CR2) on B cells,
enhancing antigen uptake and activation.
What's T cell-independent response by B cells? - correct answer T-independent (TI)
responses:
- Do not require T cell help
- TI-1 antigens (e.g., bacterial LPS) act as mitogens
- TI-2 antigens (e.g., polysaccharides) cause extensive BCR cross-linking.
What's T cell-dependent response by B cells? - correct answer T-dependent (TD)
responses:
- Require helper T cell interaction via CD40-CD40L
- cytokine signaling.
Where does B cell activation occur? - correct answer It occurs in secondary lymphoid
organs such as lymph nodes and the spleen, primarily at the border of B cell follicles
and T cell zones.
How do antigens or pathogens reach the B cell zone? - correct answer Antigens are
transported via lymphatics and are captured by subcapsular sinus macrophages or
follicular dendritic cells, which present them to B cells.
What is the first isotype of antibody made by B cells? - correct answer igm is the first
antibody produced by naïve B cells after activation.
What are various isotypes of antibodies? - correct answer 1.) Igm
2.)Igg
3.)Iga
What's BCR? - correct answer BCR (B Cell Receptor) is the antigen receptor on the
surface of B cells. It allows B cells to recognize and bind to specific antigens.
What types of antigens interact with BCR? - correct answer B cell antigens are
recognized as whole, intact, free antigens, unlike T cell antigens, which must be
processed and presented on MHC molecules.
How are B cells activated and what molecular interactions are required? - correct
answer B cell activation requires TWO signals:
Signal 1: Antigen binds to the BCR.
Signal 2: Either through interactions with helper T cells (for thymus-dependent antigens)
or through pattern recognition receptors (for thymus-independent antigens).
Additional co-receptors like CD21 and CD19 enhance signaling.
What's the role of complement in B cell activation? - correct answer Complement
components, such as c3b, interact with complement receptors (CR1, CR2) on B cells,
enhancing antigen uptake and activation.
What's T cell-independent response by B cells? - correct answer T-independent (TI)
responses:
- Do not require T cell help
- TI-1 antigens (e.g., bacterial LPS) act as mitogens
- TI-2 antigens (e.g., polysaccharides) cause extensive BCR cross-linking.
What's T cell-dependent response by B cells? - correct answer T-dependent (TD)
responses:
- Require helper T cell interaction via CD40-CD40L
- cytokine signaling.
Where does B cell activation occur? - correct answer It occurs in secondary lymphoid
organs such as lymph nodes and the spleen, primarily at the border of B cell follicles
and T cell zones.
How do antigens or pathogens reach the B cell zone? - correct answer Antigens are
transported via lymphatics and are captured by subcapsular sinus macrophages or
follicular dendritic cells, which present them to B cells.
What is the first isotype of antibody made by B cells? - correct answer igm is the first
antibody produced by naïve B cells after activation.
What are various isotypes of antibodies? - correct answer 1.) Igm
2.)Igg
3.)Iga
