A Defect in Which of the Following Proteins Blocks B-Cell

question 1

Multiple Choice

A defect in which of the following proteins blocks B-cell development at the pre-B-cell stage,resulting in almost no circulating antibodies in individuals with this defect?

• A)IL-7 receptor
• B)terminal deoxynucleotidyltransferase (TdT)
• C)Pax-5
• D)Bruton's tyrosine kinase (Btk)
• E)CD19.

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