CDK4, p53, BCL2, and PCNA antigens and a vector control were individually expressed by IVTT as GST fusion proteins, bound to anti-GST beads, and pooled. A) Within the pooled beads, individual antigens could be specifically detected with monoclonal antibodies specific to PCNA, BCL2, p53, and CDK4 at a 1:400 dilution. B) The monoclonal antibodies specific for each antigen were then pooled in different combinations: mix 2 (BCL2 and p53 Mab’s), mix 3 (PCNA, BCL2, and CDK4 Mab’s), and mix 4 (all 4 Mab’s). Each antigen could be specifically detected within the pooled antigens without loss of sensitivity or specificity.