Researchers from the University of Illinois at Urbana-Champaign have developed a highly sensitive biosensor based on a differential immuno-capture technology that can detect sub-populations of white blood cells. As part of a small, disposable biochip, the microfluidic biosensor can count CD4+/CD8+ T cells quickly and accurately for AIDS diagnosis in the field. This is a follow-up of the work earlier published by the group in Science Translational Medicine.