But perhaps the scariest fact is that even after one night of 4-5 hrs of sleep, your natural killer cells, which stop cancer cells from proliferating in your body drop by 70%.

但也许最可怕的事实是，即使只睡4-5个小时，你体内阻止癌细胞增殖的自然杀伤细胞也会减少70%。

They are called natural killer cells, and you can think of natural killer cells almost like the secret service agents of your immune system.

它们被称为自然杀伤细胞，您可以将自然杀伤细胞视为免疫系统的特工。