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?

When prescribing levothyroxine (thyroid hormone replacement) therapy for the elderly, which of the following statements is true?

Protein D consists of 120 residues and forms a dimer through an α-helix at the very C-terminus (residues 100-120). The dimer recognizes a specific 9-base pair DNA sequence. You are purifying the protein in order to determine its structure. (6 pts) A.) For the first step of the purification procedure, describe how you can use an affinity column to capture the protein. You can either design a specific affinity column or a protein construct with a specific tag. In the latter case, specify both the tag and the column that recognizes the tag. (2 pts)   B.) For the second step of the purification procedure, ion exchange chromatography is used. The isoelectric point of the protein (PI) is pH 8 and the buffers used for the ion exchange chromatography are at pH 6. Will Protein D be positively charged or negatively charged in the buffers? Should anion or cation exchange columns be used? (2 pts)   C.) For the last step of the purification procedure, gel filtration chromatography is used to separate the dimer from a small amount of monomer.  Which species, the dimer or the monomer, will elute first from the column? (2 pts)

The criteria for a recurrent major depressive disorder (MDD) specifies 2 or more episodes of MDD split by an interval of:

You hypothesize that a disulfide bond stabilizes your protein. Name one site-directed mutation and one type of chemical treatment you could use to test this hypothesis, and explain why each works. (2 pts)