This paper describes a system on a chip (SoC) that makes use of nanoscale cellular adhesion mechanisms in an integrated electronic microsystem to filter infected cells from blood or lymph. An example of a human immunodeficiency virus-specific SoC is explored in depth. Such systems work in vivo, and blood and lymph are filtered on a continuous basis. With the intelligence on the chip, captured cells can be identified and lyzed, expelled, or otherwise acted upon. These types of systems transfer the burden of research from traditional chemotherapy to bioengineering and system design.