PDCD1 and infection: T cells expressing multiple checkpoint markers, including PD‐1 and LAG‐3,137, 147, 148, 149, 150 CTLA‐4,149, 150, 151 OX40,151 and Tim‐3137, 149, 150, 152, 153 have been shown to be upregulated during infection with malaria in humans and contribute to immunosuppression.