Tipping the Scales

Science's STKE  03 Feb 2004:
Vol. 2004, Issue 218, pp. tw45-TW45
DOI: 10.1126/stke.2182004TW45

Effective immune responses depend on the precise activation and deactivation of signaling cascades by protein tyrosine kinases (PTKs) and phosphatases (PTPases). The PEST domain-enriched tyrosine phosphatase (PEP) is one such PTPase, which opposes T cell receptor signaling. Hasegawa et al. report that the loss of PEP activity in mice produced unchecked effector and memory T cell responses. Although this stopped short of causing overt autoimmunity in PEP-deficient mice, excessive B cell responses were evident, which suggests a role for the phosphatase in regulating diverse aspects of T cell-coordinated immunity.

K. Hasegawa, F. Martin, G. Huang, D. Tumas, L. Diehl, A. C. Chan, PEST domain-enriched tyrosine phosphatase (PEP) regulation of effector/memory T cells. Science 303, 685-689 (2004). [Abstract] [Full Text]