A 9-month-old boy is suspected of having an immune deficiency because he had many recurrent infections with Streptococcus pneumoniae. Laboratory tests reveal a normal percentage of T cells and T-cell subsets but 

The precipitation of immune complexes in small blood vessels under the skin that occurs when antigen is injected in an animal with large amounts of circulating antibody describes which of the following?

Which of the following tumor markers is used to test for hepatocellular carcinoma?

Which syndrome is characterized by defective apoptosis, leading to survival of lymphocytes that can react with self-antigens? 

A tumor that is classified as malignant is described as: 

Malignancies that originate from hematopoietic cells in the bone marrow are:

Which immune mechanism is involved in contact dermatitis?

In which of the following conditions would you not see an increase in alpha-fetoprotein? 

Anaphylaxis is characterized by which of the following?

A 16-year-old male goes to his physician for an annual checkup. A routine urinalysis indicates the presence of blood, an increase in protein, and an increase in urea. The young man reports that he has been feeling tired and has a persistent cough. The doctor orders additional laboratory testing, including a serum test for rheumatoid factor, antinuclear antibody testing, anti-streptolysin O testing, and testing for the presence of anti–basement membrane antibodies. Only the latter test was positive. What disease is the most likely cause of the symptoms?