Analysis of gene expression using high-density and IFN-gamma-specific low-density cDNA arrays

The combination of high and low density cDNA filter array technology potent ially permits both the identification of subsets of induced genes and conve nient and rapid multisample expression profiling of such subsets under a va riety of conditions. The JAK/STAT1 pathway for IFN-gamma signaling in human cells has been well characterized, but the extent and importance of additi onal pathways remain to be established. Here, using high-density filter arr ays of the RZPD UniGene set, we identified 18 novel IFN-gamma -inducible ge nes. Expression profiling was carried out using low-density arrays represen ting both novel and known IFN-gamma -inducible genes. Initial experiments f ailed to detect evidence for any novel non-JAK-dependent pathways in cells expressing a kinase-dead JAK2. The data, however, validated the potential o f the combined methods in establishing rapid and convenient expression prof iling of several hundred genes in response to any ligand of choice.