Schematic for MEC: 1. Transfection of host cell line, 2. Episomal replication of plasmids, 3. Protein expression, 4. Immunolabeling with BMSPA, 5. FACS, 6. Modified Hirt's extraction for plasmid recovery, 7. Plasmid electroporation into E. coli, 8. Bacterial amplification of enriched cDNA pool, 9. Preparation of enriched cDNA pool, 10. Repeat until highly enriched in BBB membrane protein-encoding cDNA.