Host genes interacting with ankyrin repeat-containing protein, p200, in Ehrlichia chaffeensis-infected monocytes. Chromatin immunoprecipitation (ChIP) together with microarray (chip) analysis demonstrated enrichment of relatively small subset (n=456) of host cell genes associated with molecular and biological processes, many of which are known to be altered during ehrlichial infection. Keywords: ChIP-chip Detection of genes with high signal enrichment by comparing the ratios of p200/input