Question 1

What might be an advantage to using an individual's own stem cells instead of pancreatic cell allografts to treat Type I diabetes?

Accepted Answer

Using a person's own cells would mean an autograft, which should not require HLA/MHC matching or long-term anti-rejection drugs.

Question 2

What is NOT a reason that the kidneys are particularly prone to damage caused by immune complexes?

Accepted Answer

The answer of What is NOT a reason that the...

Question 3

In the tuberculin skin test, what would be the most likely reason why a positive test would NOT necessarily indicate an infection in progress in a patient in the United States?

Accepted Answer

The TB skin test measures the presence of memory T cells that may have been formed during an active infection or during a prior infection that may have been cleared. Because the memory of the immune response persists, even if the patient is no longer infected, the test may still show positive.

Question 4

Why do Rh-negative but not Rh-positive mothers sometimes have babies with hemolytic disease of the newborn?

Accepted Answer

Hemolytic disease of the newborn occurs when the mother's immune system produces anti-Rh IgG antibodies that cross the placenta and attack the Rh-positive red blood cells of the fetus. Rh-negative mothers do not produce these antibodies naturally, but may be primed to produce them if they are exposed to Rh-positive blood during a previous pregnancy or transfusion. Rh-positive mothers do not produce the antibodies at all because they already have the Rh antigen on their own red blood cells, so their immune system does not recognize it as foreign. Option B is incorrect because while Rh-positive mothers do produce IgM antibodies, they can still produce IgG antibodies in response to an Rh-positive fetus. Option C is incorrect because while preventative shots with Rh immune globulin can be given to Rh-negative mothers during pregnancy and after giving birth, they do not provide protection before conception. Option D is incorrect because it is not necessarily true that Rh-negative mothers are more likely to produce antibodies; it depends on their individual exposure to Rh-positive blood.

Question 5

Multiple myeloma is a plasma cell tumor in which a clone of malignant plasma cells produces large amounts of immunoglobulin. With all this excess immunoglobulin, how can a person with multiple myeloma be immunodeficient?

Accepted Answer

Multiple myeloma results in the production of large amounts of immunoglobulin that is specific to one antigen, limiting the ability to respond to the diversity of antigens encountered. Additionally, the multiplication of malignant plasma cells may crowd out normal production of other immune cells required for protective responses. Together, these factors contribute to immunodeficiency in individuals with multiple myeloma.

Question 6

If a patient received a kidney transplant that was matched well across each of the major histocompatibility complex (MHC) molecules, but they stopped taking their anti-rejection drugs, what would happen and why?

Accepted Answer

The answer of If a patient received a kidney transplant...

Question 7

A lack of T cells makes one more vulnerable to intracellular parasites.

Accepted Answer

T cells are part of the adaptive immune system and are responsible for recognizing and eliminating infected cells, including those infected with intracellular parasites such as viruses, bacteria, and protozoa. Without sufficient T cells, the body's ability to fight off these infections is compromised, making a person more susceptible to infections from intracellular parasites.

Question 8

MHC plays a pivotal role in transplant rejection.

Accepted Answer

MHC (major histocompatibility complex) molecules present antigens to T cells, which helps the immune system recognize foreign substances. In the case of a transplant, if the donor's MHC molecules are different from the recipient's, the immune system can identify the transplanted organ as foreign and trigger an immune response to reject it. Therefore, MHC plays an important role in transplant rejection.

Quiz 17: Immunologic Disorders