Exam 6: T-Cell Mediated Immunity

Which one of the following statements about the molecule Lck is NOT true?

Which one of the following statements about MHC-TCR interactions is NOT true?

All of the following protein-protein interactions are involved in activation of naive helper T cells by antigen-presenting cells (APCs)EXCEPT:

All of the following molecules act as transcription factors in T cell activation signaling EXCEPT:

Which one of the following statements about the molecules B7-1 and B7-2 is NOT true?

Which one of the following accurately depicts the correct order of events in a TCR signal transduction pathway?

In patients with hyper IgM syndrome,there is a genetically based deficiency in expression of CD40 ligand.In addition to defects in antibody isotype switching,these patients have defects in T cell-mediated immune responses and become infected with intracellular parasites.Which one of the following normal functions of CD40 ligand is important in T cell-mediated immunity?

A 7-month-old boy,the only child of second-degree cousins,saw a pediatrician for immunologic evaluation after developing Pneumocystis carinii pneumonia.Serum IgG,IgM,and IgA levels were normal.Blood cell count showed 10,600 leukocytes/mm³ and 80% lymphocytes;90% of the lymphocytes were TCR $\alpha$$\beta$ ⁺CD4⁺.In vitro lymphocyte-proliferative responses to PHA and anti-CD3 were absent,and the pattern of tyrosine-phosphorylated cytoplasmic proteins after anti-CD3 treatment of the T cells was distinctly abnormal.This boy most likely carries homozygous mutations in the gene encoding which one of the following proteins?

All of the following are early T cell events that occur after antigen recognition by the TCR EXCEPT:

An experiment is performed in which a point mutation is introduced randomly into the Zap-70 gene for a particular strain of mice.The mutant mice display a defect in T cell development.However,precursor T cells isolated from the thymus of these mice show normal expression levels of Zap-70 of the correct molecular weight.On further in vitro analysis,the mutant Zap-70 is found to bind to ITAM motifs in the cytoplasmic tail of the $\zeta$ chain,but only when the $\zeta$ chain is phosphorylated.No phosphorylated LAT is detected,however.Given these data,in which of the following protein domains is the mutation most likely to be present?

Which one of the following cell types would be most potent at activating naive T cells?

Which one of the following descriptions of cytokine interleukin-2 is NOT true?

Which one of the following signaling molecules,if mutated,would affect B cell maturation and function primarily without affecting T cell function?

Which one of the following statements about T cells involved in an immune response is NOT true?

Damage to neurons in patients with multiple sclerosis (MS)may be caused by autoreactive T cells that recognize peptides derived from myelin proteins presented by self MHC molecules.These autoreactive T cells secrete interferon (IFN)- $\gamma$ and promote inflammation,which damages the myelin sheath surrounding neurons.The exact immunodominant epitopes recognized by autoreactive T cells in MS patents have been identified.One potential method of therapy for patients with MS is to administer therapeutic peptides that differ from the immunodominant epitopes by one or two amino acids.Which one of the following statements best describes the basis for this therapeutic approach?