Figure 1.
RPPA slides stained with CA19-9 (A) and albumin (B). Serum or plasma samples were initially diluted 1:10 then serially diluted 2-fold for a total of 6 dilutions. The 4×6 grid configuration programmed for arraying placed each sample and its dilutions in rows in each grid. The 192 sample positions on the slide include 149 unique serum and plasma samples, 30 duplicates, and 6 pancreatic cell lines. The remainder contains negative control samples consisting of lysis buffer only. (A) CA19-9 slide demonstrating sample dilution and range of signal levels between samples. Areas 1, 2, and 3 show magnified images of representative samples on corresponding locations on the slide. (B) Albumin slide demonstrating dilution and similar range of signal levels between samples. The albumin slide was printed from the same master plate as the CA19-9 slide; samples for both slides are in identical locations.