IMMUNOLOGY EXAM 3 BIOH410
KUBY IMMUNOLOGY QUESTIONS
AND ANSWERS
Thymocytes - Correct Answers -Immature T cells in thymus
Thymus settling progenators (TSP) - Correct Answers -Thymocyte precursors
Multipotent, even after arriving in thymus retain ability to become B,NK, DC, or others
Thymus - Correct Answers -Location of T-cell maturation
Organ in chest that shrinks and slows down after puberty
Notch - Correct Answers -Receptor essential in commiting stem cells to the T-cell
lineage
Notch 1 - Correct Answers -An overexpression of a constitutively active form in HSCs
would favor production of T cells over B cells in BM
Double negative thymocytes - Correct Answers -No CD4 or CD8
Double positive thymocytes - Correct Answers -Immature T cells in the thymus that are
characterized by expression of both the CD4 and the CD8 co-receptor proteins. They
represent the majority (about 80%) of thymocytes.
Thymic cortex - Correct Answers -location of T cell positive selection (lymphocyte
maturation)
Thymic selection - Correct Answers -Positive and negative selection in the thymus
Corticomedulary junction - Correct Answers -Part of thymus where cortex and medulla
meet
T cell precursors arrive here from bone marrow, travel to cortex, then medulla if they
survive + selection
TI-1 Ag - Correct Answers -Uses LBP (LPS binding protein)
LPS= lipopolysacharide, gram negative bacteria
Bind to PRRs and IgM on B1 cells
, TI-2 Ag - Correct Answers -- polymeric protein Ag and capsular polysaccharides
- crosslink many mIgM BCRs on mostly MZ B cells
CCL-19 and CCL-21 - Correct Answers -Ligands of CCR7
Expressed on HEVs and T cells zones of secondary lymphoid organs
TCR gene rearrangement - Correct Answers -Occurs in the cortex of thymus at DN3
stage
DN1 - Correct Answers -The first in the four stages in the development of the most
immature (CD4-CD8- or double negative) thymocytes. DN1 cells express CD44 but not
CD25 and are the progenitors that come from the bone marrow and have the potential
to give rise to multiple lymphoid and myeloid cell lineages.
DN2 - Correct Answers -The second in the four stages in the development of the most
immature (CD4-CD8- or double negative) thymocytes. Commitment to the T cell lineage
and rearrangement of the first TCR receptor genes occur among DN2 cells, which
express both CD44 and CD25.
T cell development phase I - Correct Answers -Takes place in thymus
Generation of an antigen receptor due to V(D)J gene rearrangement
T cell development phase II - Correct Answers -Takes place in thymus
Refinement of Ag receptor repetoire by
Positive/negative selection and lineage commitment
Positive selection - Correct Answers -Selection for T-cells that recognize MHC bound
antigens
Occurs in thymic cortex
End result: MHC restriction
cTEC - Correct Answers -Stromal cells of epithelial origin that populate the cortex of the
thymus and mediate positive selection of thymocytes.
Death by neglect - Correct Answers -Apoptosis of developing T cells (typically
CD4+CD8+ thymocytes) that results when they do not receive TCR signals of adequate
affinity. Fate of over 90% of developing T cells
Negative selection - Correct Answers -Selection against T-cell receptors that react
against self-antigens
Occurs in thymic medulla
End result: self tolerance
Lineage commitment - Correct Answers -The process during T cell development in
which CD8+, CD4+ thymocytes become CD8+ or CD4+ only
KUBY IMMUNOLOGY QUESTIONS
AND ANSWERS
Thymocytes - Correct Answers -Immature T cells in thymus
Thymus settling progenators (TSP) - Correct Answers -Thymocyte precursors
Multipotent, even after arriving in thymus retain ability to become B,NK, DC, or others
Thymus - Correct Answers -Location of T-cell maturation
Organ in chest that shrinks and slows down after puberty
Notch - Correct Answers -Receptor essential in commiting stem cells to the T-cell
lineage
Notch 1 - Correct Answers -An overexpression of a constitutively active form in HSCs
would favor production of T cells over B cells in BM
Double negative thymocytes - Correct Answers -No CD4 or CD8
Double positive thymocytes - Correct Answers -Immature T cells in the thymus that are
characterized by expression of both the CD4 and the CD8 co-receptor proteins. They
represent the majority (about 80%) of thymocytes.
Thymic cortex - Correct Answers -location of T cell positive selection (lymphocyte
maturation)
Thymic selection - Correct Answers -Positive and negative selection in the thymus
Corticomedulary junction - Correct Answers -Part of thymus where cortex and medulla
meet
T cell precursors arrive here from bone marrow, travel to cortex, then medulla if they
survive + selection
TI-1 Ag - Correct Answers -Uses LBP (LPS binding protein)
LPS= lipopolysacharide, gram negative bacteria
Bind to PRRs and IgM on B1 cells
, TI-2 Ag - Correct Answers -- polymeric protein Ag and capsular polysaccharides
- crosslink many mIgM BCRs on mostly MZ B cells
CCL-19 and CCL-21 - Correct Answers -Ligands of CCR7
Expressed on HEVs and T cells zones of secondary lymphoid organs
TCR gene rearrangement - Correct Answers -Occurs in the cortex of thymus at DN3
stage
DN1 - Correct Answers -The first in the four stages in the development of the most
immature (CD4-CD8- or double negative) thymocytes. DN1 cells express CD44 but not
CD25 and are the progenitors that come from the bone marrow and have the potential
to give rise to multiple lymphoid and myeloid cell lineages.
DN2 - Correct Answers -The second in the four stages in the development of the most
immature (CD4-CD8- or double negative) thymocytes. Commitment to the T cell lineage
and rearrangement of the first TCR receptor genes occur among DN2 cells, which
express both CD44 and CD25.
T cell development phase I - Correct Answers -Takes place in thymus
Generation of an antigen receptor due to V(D)J gene rearrangement
T cell development phase II - Correct Answers -Takes place in thymus
Refinement of Ag receptor repetoire by
Positive/negative selection and lineage commitment
Positive selection - Correct Answers -Selection for T-cells that recognize MHC bound
antigens
Occurs in thymic cortex
End result: MHC restriction
cTEC - Correct Answers -Stromal cells of epithelial origin that populate the cortex of the
thymus and mediate positive selection of thymocytes.
Death by neglect - Correct Answers -Apoptosis of developing T cells (typically
CD4+CD8+ thymocytes) that results when they do not receive TCR signals of adequate
affinity. Fate of over 90% of developing T cells
Negative selection - Correct Answers -Selection against T-cell receptors that react
against self-antigens
Occurs in thymic medulla
End result: self tolerance
Lineage commitment - Correct Answers -The process during T cell development in
which CD8+, CD4+ thymocytes become CD8+ or CD4+ only
