design: RNA was made using RNeasy (Qiagen, Germantown, MD) followed by PCR using OneStep RT-PCR Kit (Qiagen). First round VH primers HBHI-M 01-10 (iRepertoire, Huntsville, AL) conferred a unique barcode from 1-10. A second round of PCR was performed using Qiagen Multiplex PCR kit and communal primers (iRepertoire)