Based on our previous data showing that S. Typhi-specific CD8+ T cell responses can be detected as early as 4 days after typhoid fever immunization (18, 19) or challenge with S. Typhi (20), we hypothesized that changes in MAIT cell kinetics might be seen at even earlier time points (e.g., days 1 and 2) after the challenge. The gene discussed is CD8A; the disease is typhoid fever.