PHRM 3600 Exam 2 Study Guide With
Complete Solution
What is the difference between direct and indirect ELISA? - ANSWER Indirect - well is
coated with antigens and then antibodies and enzyme-linked antibodies are introduced
Direct - well is coated with antibodies and then antigens and second antibodies are
added
Western blot - ANSWER Assay that uses antibodies to detect proteins associated with
specific disease. Commonly used for HIV; tissues, complicated samples.
Drawbacks of Western blot - ANSWER Extremely expensive and highly qualitative but
not quantitative.
Lateral Flow Assay - ANSWER Utilizes gold nanoparticles that conjugate to antibodies
and move through capillary flow. Used in pregnancy tests.
Flow Cytometry - ANSWER Very complicated and quantitative; used for cells in solution.
Can differentiate between cell types.
Monoclonal antibody - ANSWER Antibody produced in labratory from tissue culture or
bacteria that is derived from ONE organism/species.
Polyclonal antibody - ANSWER Antibody derived from more than one organism/species
or eggs
What is the allelic restriction in light chain rearrangement? - ANSWER Only one
chromosome is used in light chain rearrangement, so restricted in allele that is used
RAG1 and RAG2 - ANSWER recombination proteins in lymphocytes (B and T cells) that
are involved in recombination of light chains
What segment is unique to heavy chain rearrangement? - ANSWER D (diversity)
segment
What does heavy chain rearrangement result in? - ANSWER Isotypic (class switching)
differences
What is the first C-region gene? - ANSWER Mu (IgM)
Contributing factors to diversity in chain rearrangement - ANSWER -Allelic restriction
-Junctional diversity
-Hypermutation
, -Affinity maturation
CD marker involved in all stages of B cell differentiation - ANSWER CD19
CD marker involved in earliest stages of B cell differentiation (Pro-B and pre-B) -
ANSWER CD10
CD marker involved in immature to memory B cell differentiation - ANSWER CD20
CD marker involved at latest stage of B cell differentiation - ANSWER CD27
What stage of B cell differentiation are the light chains expressed? - ANSWER Pre-B
What stage of B cell differentiation is IgM expressed? - ANSWER Immature B
What stage of B cell differentiation are both IgM and IgD expressed? - ANSWER Mature
B
What stage of B cell differentiation involved isotype switch? - ANSWER Memory B or
plasma cell
Igalpha and Igbeta - ANSWER Expressed on surface of B cell as part of B cell receptor
complex with light chains; sends signals to nucleus
Negative Selection of B cells - ANSWER Central tolerance; B cells that express BCR for
self-antigen are removed and only BCRs with nonself-antigens are allowed to leave the
bone marrow
Germinal center - ANSWER Area found within the lymph node that are responsible for
differentiation and production of lymphocytes.
Describe the differentiation of lymphocytes in the germinal centers - ANSWER
Antigen-specific B cells and activated CD4+ T cell interact in germinal center and select
B cell with high affinity for antigens, and cause death of B cells with low affinity for
antigen.
CD40 - ANSWER B cell CD marker that interacts with CD40L and induces class switch
recombination
MHC Class II - ANSWER Found on antigen-presenting cells; binds peptide and presents
to TCR of CD4+ cell
T Cell Independent B cell activation - ANSWER Binding of Ig receptor and CD21 to
antigen and activate B cell co-receptor and activate B cell response without T cell
activation
XLA - ANSWER X-linked agammaglobulinemia; lack of Btk protein causes pro-B cells not
to mature into pre-B and hence a complete lack of B cells, which leads to lack of
antibodies of all classes. Treated by IV immunoglobulin.
Complete Solution
What is the difference between direct and indirect ELISA? - ANSWER Indirect - well is
coated with antigens and then antibodies and enzyme-linked antibodies are introduced
Direct - well is coated with antibodies and then antigens and second antibodies are
added
Western blot - ANSWER Assay that uses antibodies to detect proteins associated with
specific disease. Commonly used for HIV; tissues, complicated samples.
Drawbacks of Western blot - ANSWER Extremely expensive and highly qualitative but
not quantitative.
Lateral Flow Assay - ANSWER Utilizes gold nanoparticles that conjugate to antibodies
and move through capillary flow. Used in pregnancy tests.
Flow Cytometry - ANSWER Very complicated and quantitative; used for cells in solution.
Can differentiate between cell types.
Monoclonal antibody - ANSWER Antibody produced in labratory from tissue culture or
bacteria that is derived from ONE organism/species.
Polyclonal antibody - ANSWER Antibody derived from more than one organism/species
or eggs
What is the allelic restriction in light chain rearrangement? - ANSWER Only one
chromosome is used in light chain rearrangement, so restricted in allele that is used
RAG1 and RAG2 - ANSWER recombination proteins in lymphocytes (B and T cells) that
are involved in recombination of light chains
What segment is unique to heavy chain rearrangement? - ANSWER D (diversity)
segment
What does heavy chain rearrangement result in? - ANSWER Isotypic (class switching)
differences
What is the first C-region gene? - ANSWER Mu (IgM)
Contributing factors to diversity in chain rearrangement - ANSWER -Allelic restriction
-Junctional diversity
-Hypermutation
, -Affinity maturation
CD marker involved in all stages of B cell differentiation - ANSWER CD19
CD marker involved in earliest stages of B cell differentiation (Pro-B and pre-B) -
ANSWER CD10
CD marker involved in immature to memory B cell differentiation - ANSWER CD20
CD marker involved at latest stage of B cell differentiation - ANSWER CD27
What stage of B cell differentiation are the light chains expressed? - ANSWER Pre-B
What stage of B cell differentiation is IgM expressed? - ANSWER Immature B
What stage of B cell differentiation are both IgM and IgD expressed? - ANSWER Mature
B
What stage of B cell differentiation involved isotype switch? - ANSWER Memory B or
plasma cell
Igalpha and Igbeta - ANSWER Expressed on surface of B cell as part of B cell receptor
complex with light chains; sends signals to nucleus
Negative Selection of B cells - ANSWER Central tolerance; B cells that express BCR for
self-antigen are removed and only BCRs with nonself-antigens are allowed to leave the
bone marrow
Germinal center - ANSWER Area found within the lymph node that are responsible for
differentiation and production of lymphocytes.
Describe the differentiation of lymphocytes in the germinal centers - ANSWER
Antigen-specific B cells and activated CD4+ T cell interact in germinal center and select
B cell with high affinity for antigens, and cause death of B cells with low affinity for
antigen.
CD40 - ANSWER B cell CD marker that interacts with CD40L and induces class switch
recombination
MHC Class II - ANSWER Found on antigen-presenting cells; binds peptide and presents
to TCR of CD4+ cell
T Cell Independent B cell activation - ANSWER Binding of Ig receptor and CD21 to
antigen and activate B cell co-receptor and activate B cell response without T cell
activation
XLA - ANSWER X-linked agammaglobulinemia; lack of Btk protein causes pro-B cells not
to mature into pre-B and hence a complete lack of B cells, which leads to lack of
antibodies of all classes. Treated by IV immunoglobulin.
