Pax5 transcription factors play a major role in the differentiation of these cells by promoting the expression of their co-receptor CD19. For 10 points each:
[10e] Name these cells deficient in X-linked agammaglobulinemia, resulting in patients producing little antibodies. These cells mature in bone marrow in contrast to another class of immune cells that mature in the thymus.
ANSWER: B lymphocytes [or B cells; accept pro-B cells or pre-B cells; accept plasma cells]
[10m] One of these enzymes, first identified by Ogden Bruton, is defective in XLA. After cytokine receptors dimerize, the Janus type of these enzymes transphosphorylates each other at a certain amino acid residue.
ANSWER: tyrosine kinases [or TKs; accept Bruton’s tyrosine kinases or BTKs; accept Janus tyrosine kinases; accept receptor tyrosine kinases or RTKs; accept non-receptor tyrosine kinases or NRTKs; prompt on kinases; prompt on JAKs or JAK-STAT signaling]
[10h] During negative selection, self-reactive B cells can enter this state of unresponsiveness to any stimulatory signal. In the absence of co-stimulatory CD28, T cells enter this state via a calcium-dependent NFAT pathway.
ANSWER: anergy [accept clonal anergy; accept anergic state; reject “dormancy”]
<Michigan B, Biology>