O#13   Microarray analysis of human, rat, and mouse dermal papilla and connective tissue sheath cells reveals multiple factors with potential for hair follicle growth regulation

Kevin J. McElwee1, Christian Maercker2, Rolf Hoffmann1. 1Dept of Dermatology, Philipp University, Marburg, Germany; 2German Resource Center for Genome Research at the German Cancer Research Center (molecular genome analysis), Heidelberg, Germany

Previous research has demonstrated the potential of dermal papilla (DP) cells to induce hair follicle development whereas connective tissue sheath (CTS) cells do not. We compared the gene-expression profiles of hair follicle derived cultured DP cells versus CTS cells obtained from humans, PVG/OlaHsd rats and C3H/HeJ mice using cDNA arrays with the capacity to display transcript levels of 33,000, 25,000, and 27,000 genes or ESTs respectively. This approach resulted in the identification of 62 differentially expressed known genes (ratio 5:1 or greater), encoding products involved in morphogenic signalling, transcriptional regulation, extra-cellular matrix modelling, cell structure and motility. Of greatest interest, significant DP cell expression was noted for HGFAC, MMP1, MMP3, TMSB10, F3, ICAM3, and UDGH. Significant CTS cell expressed genes included IGFBP2, IGFBP4, ATDC, ANXA6, EXTL1, GLI2, and SOS1. Immunohistochemical analysis with monoclonal antibodies to selected gene products identified with human micro arrays confirmed relevant expression patterns in hair follicles as predicted by array analysis. Gene expression profiling using cDNA arrays is a comprehensive approach to evaluating hair follicle compartments. By profiling hair follicles at different stages during embryological development and cycling it may be possible to identify the key regulatory products involved. Profiling normal versus disease affected hair follicle compartments may also reveal regulatory factors behind the disease and identify candidate genes for targeting with new therapeutic regimes.