PCB 3233 Immunology Exam 4 questions with correct
answers
Positive Selection - ** VERIFIED ANSWERS **✔✔makes sure that your T-Cell recognizes one of
your MHC.
If it does not, then apoptosis
Negative Selection - ** VERIFIED ANSWERS **✔✔Makes sure it does not recognize your
peptide:MHC too strongly
Does gamma: delta T-cells have to go through positive selection? - ** VERIFIED ANSWERS **✔✔No
What does turning off RAG 1&2 do to your gene rearrangement? - ** VERIFIED ANSWERS
**✔✔Preserve the current rearrangement
Primary Lymphoid Tissue - ** VERIFIED ANSWERS **✔✔bone marrow and thymus
What does TH1 cells do? - ** VERIFIED ANSWERS **✔✔Activate macrophages
Thymal Stromal Cells - ** VERIFIED ANSWERS **✔✔Keeps BCR genes closed and opens TCR
genes
IgM activates? - ** VERIFIED ANSWERS **✔✔complement
Notch-1 - ** VERIFIED ANSWERS **✔✔The signal for survival. It drives the cell on the T-cell path
— signals to open up T-cell rearrangement.
Signaling rearrangement keeps T-cel on T-cell pathway
,Where does Maturation and Positive Selection occur? - ** VERIFIED ANSWERS **✔✔Cortex of the
thymus
Can negative selection also take place in the Cortex? - ** VERIFIED ANSWERS **✔✔Yes, negative
selection can take place in the cortex at the same time as positive selection
Where does negative selection take place? - ** VERIFIED ANSWERS **✔✔medulla of thymus
Where are mature thymocytes located? - ** VERIFIED ANSWERS **✔✔Medulla
Where are immature thymocytes located? - ** VERIFIED ANSWERS **✔✔Cortex
What special cells are in the Medulla - ** VERIFIED ANSWERS **✔✔Dendritic cells, macrophages,
and medullary epithelial cells
What special cells are in the cortex? - ** VERIFIED ANSWERS **✔✔Cortical epithelial cells and
macrophages
Where can you find AIRE? - ** VERIFIED ANSWERS **✔✔in the medullary epithelial cells
AIRE - ** VERIFIED ANSWERS **✔✔Autoimmune regulator
made by medullary epithelial cells
Creates a couple hundred peripheral peptides that can be used to test T-cells for negative selection
DiGeorge's syndrome - ** VERIFIED ANSWERS **✔✔deletion in chromosome 22 in which thymus
fails to develop and T-cells are absent
, Hassall's corpuscles - ** VERIFIED ANSWERS **✔✔macrophages in both cortex and medulla
remove the many thymocytes that fail to mature properly
Involution of the Thymus - ** VERIFIED ANSWERS **✔✔Progressively shrinks, fat gradually
claiming areas once packed with thymocytes
-reduces production of new T-cells
Double negative - ** VERIFIED ANSWERS **✔✔No CD4 and CD8
Double Positive - ** VERIFIED ANSWERS **✔✔CD4 and CD8 are present
Single Positive - ** VERIFIED ANSWERS **✔✔has either CD4 or CD8
CD2 and CD5 - ** VERIFIED ANSWERS **✔✔perform adhesion and signaling. They are present
during double negative stage
Thymocytes rearrange which 3 genes at the same time? - ** VERIFIED ANSWERS **✔✔Beta,
gamma, and delta
pTalpha - ** VERIFIED ANSWERS **✔✔surrogate alpha chain. signals cell to halt gamma, delta,
Beta chains, gene rearrangement and begin proliferation.
What do macrophages do in the thymus? - ** VERIFIED ANSWERS **✔✔continually remove dead
cells
How many rearrangements can successfully make a Beta chain? - ** VERIFIED ANSWERS **✔✔up
to 4 attempts
d:k light chain can have a minimum of how many rearrangements? - ** VERIFIED ANSWERS
**✔✔4 minimum attempts
answers
Positive Selection - ** VERIFIED ANSWERS **✔✔makes sure that your T-Cell recognizes one of
your MHC.
If it does not, then apoptosis
Negative Selection - ** VERIFIED ANSWERS **✔✔Makes sure it does not recognize your
peptide:MHC too strongly
Does gamma: delta T-cells have to go through positive selection? - ** VERIFIED ANSWERS **✔✔No
What does turning off RAG 1&2 do to your gene rearrangement? - ** VERIFIED ANSWERS
**✔✔Preserve the current rearrangement
Primary Lymphoid Tissue - ** VERIFIED ANSWERS **✔✔bone marrow and thymus
What does TH1 cells do? - ** VERIFIED ANSWERS **✔✔Activate macrophages
Thymal Stromal Cells - ** VERIFIED ANSWERS **✔✔Keeps BCR genes closed and opens TCR
genes
IgM activates? - ** VERIFIED ANSWERS **✔✔complement
Notch-1 - ** VERIFIED ANSWERS **✔✔The signal for survival. It drives the cell on the T-cell path
— signals to open up T-cell rearrangement.
Signaling rearrangement keeps T-cel on T-cell pathway
,Where does Maturation and Positive Selection occur? - ** VERIFIED ANSWERS **✔✔Cortex of the
thymus
Can negative selection also take place in the Cortex? - ** VERIFIED ANSWERS **✔✔Yes, negative
selection can take place in the cortex at the same time as positive selection
Where does negative selection take place? - ** VERIFIED ANSWERS **✔✔medulla of thymus
Where are mature thymocytes located? - ** VERIFIED ANSWERS **✔✔Medulla
Where are immature thymocytes located? - ** VERIFIED ANSWERS **✔✔Cortex
What special cells are in the Medulla - ** VERIFIED ANSWERS **✔✔Dendritic cells, macrophages,
and medullary epithelial cells
What special cells are in the cortex? - ** VERIFIED ANSWERS **✔✔Cortical epithelial cells and
macrophages
Where can you find AIRE? - ** VERIFIED ANSWERS **✔✔in the medullary epithelial cells
AIRE - ** VERIFIED ANSWERS **✔✔Autoimmune regulator
made by medullary epithelial cells
Creates a couple hundred peripheral peptides that can be used to test T-cells for negative selection
DiGeorge's syndrome - ** VERIFIED ANSWERS **✔✔deletion in chromosome 22 in which thymus
fails to develop and T-cells are absent
, Hassall's corpuscles - ** VERIFIED ANSWERS **✔✔macrophages in both cortex and medulla
remove the many thymocytes that fail to mature properly
Involution of the Thymus - ** VERIFIED ANSWERS **✔✔Progressively shrinks, fat gradually
claiming areas once packed with thymocytes
-reduces production of new T-cells
Double negative - ** VERIFIED ANSWERS **✔✔No CD4 and CD8
Double Positive - ** VERIFIED ANSWERS **✔✔CD4 and CD8 are present
Single Positive - ** VERIFIED ANSWERS **✔✔has either CD4 or CD8
CD2 and CD5 - ** VERIFIED ANSWERS **✔✔perform adhesion and signaling. They are present
during double negative stage
Thymocytes rearrange which 3 genes at the same time? - ** VERIFIED ANSWERS **✔✔Beta,
gamma, and delta
pTalpha - ** VERIFIED ANSWERS **✔✔surrogate alpha chain. signals cell to halt gamma, delta,
Beta chains, gene rearrangement and begin proliferation.
What do macrophages do in the thymus? - ** VERIFIED ANSWERS **✔✔continually remove dead
cells
How many rearrangements can successfully make a Beta chain? - ** VERIFIED ANSWERS **✔✔up
to 4 attempts
d:k light chain can have a minimum of how many rearrangements? - ** VERIFIED ANSWERS
**✔✔4 minimum attempts
