Exam 4: Antigen Recognition in the Adaptive Immune System

A 15-year-old girl develops malaise, headache, and low-grade fever, followed by pharyngitis and cervical lymph node enlargement as a result of infectious mononucleosis caused by Epstein-Barr virus (EBV). Her acute symptoms resolve within 2 weeks, and the fatigue improves within 3 months. All of the following are required for CD8⁺ cytotoxic T lymphocyte (CTL) recognition and killing of EBV-infected cells EXCEPT:

Both CD28 and CTLA-4 are receptors on T cells that are critical for regulating T cell activation. In which one of the following ways does CD28 differ from CTLA-4?

Neonates, elderly persons, and otherwise immunocompromised patients are particularly susceptible to infections with Listeria monocytogenes. These patients typically have fever and chills, often progressing to hypotension and septic shock. In healthy individuals, however, such intracellular microbes are usually effectively phagocytosed and killed by macrophages, which become activated via:

CD44 expressed on the surface of T cells is critical for the binding of activated T cells to endothelium at sites of inflammation, and for the retention of T cells in extravascular tissues at sites of infection. CD44 does this by binding to which one of the following molecules?

The strength of integrin-dependent binding of T cells to antigen-presenting cells (APCs) may be rapidly increased by which one of the following mechanisms?

Selectins differ from integrins in which one of the following ways?

T cells may be important for recognition of common antigens at epithelial boundaries between the host and the external environment. The T cells differ from the αβ T cells in which one of the following ways?

CD8 is a protein that functions as a coreceptor for a subset of T cells and plays a significant role in all of the following EXCEPT:

A 15-year-old girl develops malaise, headache, and low-grade fever, followed by pharyngitis and cervical lymph node enlargement as a result of infectious mononucleosis caused by Epstein-Barr virus (EBV). Her acute symptoms resolve within 2 weeks, and the fatigue improves within 3 months. Following the primary infection described in this patient, the patient's subsequent exposure to Epstein-Barr virus (EBV) will trigger clonal expansion of EBV-specific T cells expressing which one of the following surface molecules?

After 2 years of hard work, a graduate student finally succeeds in creating a gene knockout mouse lacking CD4. The student is particularly careful to keep this mouse line in a microbe-free animal facility because these mice are expected to show:

CD1-restricted T cells differ from other T cells restricted to class I or class II MHC molecules in which one of the following ways?

Most T lymphocytes have a dual specificity for which one of the following pairs of molecules?

Which of the following is NOT a property shared by both CD4 and CD8?

A 2-year-old boy suffers from recurrent bacterial infection of his ears, sinuses, lungs, and skin; laboratory studies indicate absence of sialylated Lewis X on his leukocytes. He is diagnosed with leukocyte adhesion deficiency type 2 (LAD-2). Which type of adhesive interaction required for leukocyte migration is defective in this boy?

The T cell receptor (TCR) complex differs from an immunoglobulin molecule in which one of the following ways?

LFA-1 is an integrin that promotes T cell activation by which one of the following mechanisms?

A healthy 45-year-old child-care worker becomes infected with a virus and develops a sore throat, cough, and fever. Infected cells in the bronchial mucosa of this patient process virus-encoded proteins through an intracellular pathway and display peptides derived from the protein on the cell surface bound to class I MHC molecules. CD8⁺ T cells migrate to the mucosa and recognize these peptide-MHC complexes. Which of the following components of the TCR actually bind to the viral peptide-MHC complex?