Protein expression in 24 well blocks and 50 ml flask culture. Supernatants from 50 ml shake flask (A) and 2 ml 24 well block (B) transient transfections were analysed by Cy5 western blot. The 13 vectors which are positive for protein production are indicated by arrows. In B, the two different seeding density samples from the 24 well blocks were run adjacent to each other with the lower seeding density sample loaded first. The control protein C was rCD4 (domains 3 + 4)-His10 expressed from vector C, Figure 1.