New roles for TIM family members in immune regulation

Vijay K Kuchroo1, Valerie Dardalhon, Sheng Xiao

  • 1Center for Neurologic Diseases, Brigham and Women's Hospital, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, Massachusetts 02115, USA. vkuchroo@rics.bwh.harvard.edu

Members of the TIM (T-cell immunoglobulin domain and mucin domain) protein family are emerging as important regulators of immune responses. As their names imply, the TIM proteins were originally thought to be T-cell-specific molecules that served mainly to regulate T-helper-cell responses. However, the recent discovery that antigen-presenting cells also express TIM molecules and the identification of new TIM-protein ligands has expanded the known roles of the TIM proteins in immune regulation.

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