Clinical Case: “The College Freshman” Chief Complaint An 18-year-old female college freshman presents to the student health clinic with a 3-day history of fever (38.8°C), sore throat, fatigue, enlarged cervical lymph nodes, and malaise. She reports that she recently moved into a dormitory and was advised during orientation to receive a meningococcal vaccine but delayed vaccination because she “felt healthy.” History of Present Illness Three weeks earlier, one of her roommates had a viral respiratory illness. The patient now complains of fever and fatigue, tender cervical lymphadenopathy, sore throat, mild headache and reduced appetite. Laboratory studies reveal WBC counts elevated, Lymphocytes-increased, Serum IgM elevated, Serum IgG low-normal and Viral PCR positive for EBV. 

 The patient finally receives her meningococcal vaccine. Question 12. How does vaccination protect against future infection?

Junctional diversity is greatest within:

All complement pathways converge on:

Which mechanism contributes to antibody diversity but not significantly to TCR diversity?

TI-1 antigens activate B cells through:

A researcher studying the patient’s antibodies introduces mutations into the hypervariable region. Question 8. What would be most affected?

Attachment of C3d to antigen can increase immunogenicity approximately:

Secretory component protects IgA from:

Which event occurs first in heavy-chain rearrangement?