HDAC1 and colitis: Third, IEC-restricted HDAC1/2 disruption leads to chronic intestinal inflammation in the colon, with colitis symptoms such as decreased weight, looser stools and colon shortening, as well as immune cell infiltrates and altered expression of immune related genes in colon, as assessed by microarray and RNA expression analysis, and elevated phosphorylation of the transcription factor Stat3, a regulator of inflammation [32].