T cells are fierce warriors. With just a hint of an attack—be it an infection or a nascent cancer—they rally, ramp up in numbers, and launch a full-scale defense. But they’re not invincible. Sometimes the cellular soldiers become overzealous, attacking friendly tissues. Or their defenses are wiped out by particularly heinous foes, like HIV and … Continue reading CRISPR On-Off Switch Will Help Unlock the Secrets of Our Immune System