05-01-2014, 05:30 PM
A 3-year old child has dyspnea, severe cough, and a fever. A chest X-ray and laboratory tests lead to a diagnosis of Pneumocystis jirovecii pneumonia. Further laboratory tests indicate abnormally low levels of the IgG, IgA, and IgE immunoglobulins. However, levels of IgM are far above normal. This patient's immune deficiency is caused by a defect in which cell surface molecules?
a. CD40 ligand
b. CD86
c. Fas ligand
d. TCR
e. TNF receptor
a. CD40 ligand
b. CD86
c. Fas ligand
d. TCR
e. TNF receptor
