Fig. 1.

T cell interaction with micropatterned, costimulatory arrays. (A) CD4⁺ cells were presented with surfaces that capture the microscale organization of ligands associated with T cell costimulation. Colocalized patterns were created by mixing anti-CD3 and anti-CD28 antibodies (yellow) in a single step (B), while segregated patterns were defined by sequential patterning of anti-CD3 (red) and anti-CD28 (green) on a single surface (C). (Inset) Fluorescence profile across a segregated site. ICAM-1 was coated onto the remainder of these surfaces but is omitted here for clarity. (Scale bar: 10 μm.)