Question

1. Provide an example of a person with a particular blood type that should NOT donate to another person with a particular blood type. Make sure to include the immunology.

2. OUTLINE the reasons why treating a cancer patient with chemotherapy might make them more susceptible to infections.

Answer 1

1. Antibodies are proteins that are secreted by the immune cells of the body. Antibodies protect the body from infections by fighting against the invading bacteria and viruses.

Antigens are the substances that are usually made up of carbohydrates or proteins, which triggers an immune response resulting in the secretion of antibodies targeted against them.

Antibodies are very specific against specific kind of antigens. Antibodies will not be secreted for the self antigens that are present in the body. They will be secreted only against the foreign antigens.

In terms of blood types:

A person with A blood type will have B antibodies in the plasma of the blood.

A person with B blood type will have A antibodies in the plasma.

A person with AB blood type will neither have A nor B antibodies in the plasma.

A person with O blood type will have both A and B antibodies.

For example:

If a person with O blood type receives blood from a person with blood type B. Then the receipients immune system would recognize the donors blood cells as foreign and secrete antibodies to destroy them. Antibodies that are secreted will bind to the antigens on the surface of the red blood cells and rupture them to death.

2. Chemotherapy uses chemical drugs to kill the fast growing cancer cells in the body.

As chemotherapy drugs target the rapidly dividing cancer cells, they also act against some of the normal cells of the body that also divide rapidly, especially cells of the bone marrow.

Bone marrow is the site that produces white blood cells. When the number of white blood cells in the body is decreased, the body is more prone for infections.

The most important type of white blood cells is neutrophils - the first responder to bacterial infections. The neutrophil levels in the blood would decrease immediately after a week of chemotherapy. If the neutrophil count falls below 1000, the condition bus called as neutropenia. The normal neutrophil count is 2500 to 6000. In this case, the body is very much prone to infections.