Cell recognition and the immune system：练习题

Which of the following statements correctly identifies the role of T helper cells in the cellular immune response?

Which of the following statements regarding monoclonal antibodies is correct?

In an indirect ELISA test used to detect the presence of HIV antibodies in a patient's blood, the following steps are performed:
1. HIV antigens are attached to the test well.
2. Patient serum is added.
3. The well is washed.
4. An enzyme-linked antibody is added.
5. The well is washed again.
6. Substrate is added.
What is the specific purpose of step 5?

A patient is undergoing an indirect ELISA test to detect the presence of antibodies against a specific pathogen. After the patient's serum is added to the antigen-coated well and incubated, which of the following is the most critical purpose of the wash step performed before adding the enzyme-conjugated secondary antibody?

A vaccine contains a weakened version of a pathogen. This leads to the development of herd immunity within a population. How does herd immunity primarily protect unvaccinated individuals?

During the process of phagocytosis, which specific type of enzyme is released from lysosomes to destroy the ingested pathogen?

In the context of cell recognition, define the term antigen and explain how a change in its structure can affect the body's immune response to a pathogen.

A specific monoclonal antibody is used in a medical treatment to target cancer cells. Explain how the quaternary structure of the antibody allows it to be highly specific to only one type of antigen found on the surface of the tumor cells.

When a pathogen enters the body, the immune system initiates a complex series of events to provide both immediate and long-term protection.

a) Explain how phagocytosis of a bacterial cell leads to the activation of the cellular immune response. (3 points)

b) Describe the role of effector B cells (plasma cells) in the humoral response and explain how the structure of an antibody allows it to cause the destruction of bacterial pathogens. (3 points)

c) A patient is given a booster vaccine. Explain why the concentration of antibodies increases much more rapidly and reaches a higher peak following this second exposure compared to the primary response. (2 points)