The Microfluidic Trapping of Antibody-Secreting Cells

Abstract

Therapeutic antibodies (Abs) can activate biochemical attacks against specific antigens (Ags) and recruit immune cells to destroy bound pathogens1. We are contributing to a multidisciplinary project developing a sensor array to monitor the Ab production by thousands of Ab-secreting cells (ASCs) on a single slide, affording real-time identification of the ASCs producing the desired Ag-specific Abs with the strongest affinities. From these ASCs, messenger RNA and thus complementary DNA can be prepared and amplified, cloned into Abexpression vectors, and used to create ASC lines producing the desired Abs.

Each ASC shall be microfluidically guided and trapped near an individual Ab sensor composed of a thin gold film milled with an array of nanoholes to which Ag is immobilized. The binding of secreted Abs to the Ag alters the optical transmission through the nanohole array via the generation and transmission of surface plasmons2. The Abs secreted by each ASC shall be monitored simultaneously via the optical transmission through each nanohole array.

This paper shall present the initial progress of our contribution to this project: the development of the microfluidic devices for guiding and trapping large numbers of ASCs. We have previously demonstrated the integration of nanohole array sensors with polymer-based microfluidic channels3. We now present several different polymer-based microfluidic trapping devices, which we have evaluated using COMSOL® simulations and tested using bead- and cellbased flow experiments.