CHS Practice Exam (Certified
Histocompatibility Specialist)
Questions & Answers63
Human serum accidentally contaminates the AHG stock solution. What is the expected effect in
the
AHH-CDC assay?
a. No effect
b. Decreased specificity and many false positive reactions
c. Many false negative reactions
d. Decreased CYNAP effect - ANSWERS-Many false negative reactions
Which is a valid separation technology?
a. T cells via surface IgM binding to magnetic beads
b. Macrophages via uptake of iron filings
c. B cells via CD8 binding to magnetic beads
d. Neutrophils via segregation into the buffy coat layer of a standard ficoll-hypaque gradient -
ANSWERS-Macrophages via uptake of iron filings
Which of the following would substantially (and always) interfere with a 3-color flow
crossmatch?
a. Patient undergoing treatment with IVIg
b. Patient undergoing treatment with anti-CD20 monoclonal antibody
c. Patient has leukemia
d. Patient previously had solid organ transplant and is now preparing for stem cell transplant -
ANSWERS-Patient undergoing treatment with anti-CD20 monoclonal antibody
,An AML patient in blast crisis types heterozygous for HLA-A,B by serology but homozygous by
molecular SBT. The molecular and serological typings both started from freshly drawn ACD
tubes and both
typings meet all interpretive criteria without apparent anomaly. Which explanation best
explains the data?
a. Patient received a recent transfusion
b. Patient has deranged lymphocytes that express extra HLA's
c. Patient has recently received anti-proliferative chemotherapy
d. Patient's AML cells differ from patient's lymphocytes in HLA expression - ANSWERS-Patient's
AML cells differ from patient's lymphocytes in HLA expression
Which of the following is not a secondary lymphoid organ?
a. Spleen
b. Thymus
c. Lymph nodes
d. Liver
e. Tonsils - ANSWERS-Thymus
Primary lymphatic organs are where lymphocytes are formed and mature.
stem cells to divide and mature into B- and T- cells:
There are two primary lymphatic organs: the red bone marrow and the thymus gland.
Which of the following is not a component of the reticuloendothelial cell system?
a. Microglial cells
b. Kupffer cells
c. Langerhans cells
,d. Neutrophils
e. Monocytes - ANSWERS-Neutrophils
Macrophages = tissue
Monocytes = blood
Kupffer cells = liver
Microgial cells = nervous system
Langerhans = skin
Not = endothelial cells, fibroblasts, and most leukocytes
Opsonization is a term to describe what?
a. Lysis of bacteria
b. Coating of bacteria
c. Ingestion of bacteria
d. Killing of bacteria
e. Phagocytosis - ANSWERS-Coating of bacteria
Antibody opsonization is the process by which a pathogen is marked for ingestion and
eliminated by a phagocyte.
Which of the following does not describe a role of antibodies in host defense?
a. They serve as a bridge between bacteria and phagocytes
b. They lyse bacteria
c. They enhance complement binding to the bacterial cell wall
d. They prevent viruses from infecting cells
e. They bind pathogens in mucus secretions - ANSWERS-They lyse bacteria
, MHC Class I and II molecules differ in all of the following except
a. Types of T cells they stimulate
b. Types of cells they are expressed on
c. Which chromosome they are located on
d. Types of antigens they present
e. Whether or not they have foreign peptides in the antigen-binding groove - ANSWERS-Which
chromosome they are located on
The primary role of the proteasome in antigen presentation is to
a. Prevent premature folding of MHC class I molecules
b. Process cytoplasmic proteins
c. Degrade recycled MHC molecules
d. Bind HLA-DM in the endosome
e. Chaperone peptides to the cell surface - ANSWERS-Process cytoplasmic proteins
The main function of the proteasome is to degrade unneeded or damaged proteins by
proteolysis, a chemical reaction that breaks peptide bonds.
Peptides that bind to MHC class I molecules differ from peptides that bind to MHC class II
molecules in all
except which of the following ways?
a. They are shorter
b. They were processed by different proteases
c. They anchor in the middle instead of the end of the MHC molecule
d. They interact with different subsets of T cells - ANSWERS-They anchor in the middle instead
of the end of the MHC molecule
Histocompatibility Specialist)
Questions & Answers63
Human serum accidentally contaminates the AHG stock solution. What is the expected effect in
the
AHH-CDC assay?
a. No effect
b. Decreased specificity and many false positive reactions
c. Many false negative reactions
d. Decreased CYNAP effect - ANSWERS-Many false negative reactions
Which is a valid separation technology?
a. T cells via surface IgM binding to magnetic beads
b. Macrophages via uptake of iron filings
c. B cells via CD8 binding to magnetic beads
d. Neutrophils via segregation into the buffy coat layer of a standard ficoll-hypaque gradient -
ANSWERS-Macrophages via uptake of iron filings
Which of the following would substantially (and always) interfere with a 3-color flow
crossmatch?
a. Patient undergoing treatment with IVIg
b. Patient undergoing treatment with anti-CD20 monoclonal antibody
c. Patient has leukemia
d. Patient previously had solid organ transplant and is now preparing for stem cell transplant -
ANSWERS-Patient undergoing treatment with anti-CD20 monoclonal antibody
,An AML patient in blast crisis types heterozygous for HLA-A,B by serology but homozygous by
molecular SBT. The molecular and serological typings both started from freshly drawn ACD
tubes and both
typings meet all interpretive criteria without apparent anomaly. Which explanation best
explains the data?
a. Patient received a recent transfusion
b. Patient has deranged lymphocytes that express extra HLA's
c. Patient has recently received anti-proliferative chemotherapy
d. Patient's AML cells differ from patient's lymphocytes in HLA expression - ANSWERS-Patient's
AML cells differ from patient's lymphocytes in HLA expression
Which of the following is not a secondary lymphoid organ?
a. Spleen
b. Thymus
c. Lymph nodes
d. Liver
e. Tonsils - ANSWERS-Thymus
Primary lymphatic organs are where lymphocytes are formed and mature.
stem cells to divide and mature into B- and T- cells:
There are two primary lymphatic organs: the red bone marrow and the thymus gland.
Which of the following is not a component of the reticuloendothelial cell system?
a. Microglial cells
b. Kupffer cells
c. Langerhans cells
,d. Neutrophils
e. Monocytes - ANSWERS-Neutrophils
Macrophages = tissue
Monocytes = blood
Kupffer cells = liver
Microgial cells = nervous system
Langerhans = skin
Not = endothelial cells, fibroblasts, and most leukocytes
Opsonization is a term to describe what?
a. Lysis of bacteria
b. Coating of bacteria
c. Ingestion of bacteria
d. Killing of bacteria
e. Phagocytosis - ANSWERS-Coating of bacteria
Antibody opsonization is the process by which a pathogen is marked for ingestion and
eliminated by a phagocyte.
Which of the following does not describe a role of antibodies in host defense?
a. They serve as a bridge between bacteria and phagocytes
b. They lyse bacteria
c. They enhance complement binding to the bacterial cell wall
d. They prevent viruses from infecting cells
e. They bind pathogens in mucus secretions - ANSWERS-They lyse bacteria
, MHC Class I and II molecules differ in all of the following except
a. Types of T cells they stimulate
b. Types of cells they are expressed on
c. Which chromosome they are located on
d. Types of antigens they present
e. Whether or not they have foreign peptides in the antigen-binding groove - ANSWERS-Which
chromosome they are located on
The primary role of the proteasome in antigen presentation is to
a. Prevent premature folding of MHC class I molecules
b. Process cytoplasmic proteins
c. Degrade recycled MHC molecules
d. Bind HLA-DM in the endosome
e. Chaperone peptides to the cell surface - ANSWERS-Process cytoplasmic proteins
The main function of the proteasome is to degrade unneeded or damaged proteins by
proteolysis, a chemical reaction that breaks peptide bonds.
Peptides that bind to MHC class I molecules differ from peptides that bind to MHC class II
molecules in all
except which of the following ways?
a. They are shorter
b. They were processed by different proteases
c. They anchor in the middle instead of the end of the MHC molecule
d. They interact with different subsets of T cells - ANSWERS-They anchor in the middle instead
of the end of the MHC molecule
