Human normal-resting epidermal Langerhans cells do express the type 3 complement receptor

Abstract
The expression of CR3 by murine-resting epidermal Langerhans cells (LC) is well established, but CR3 expression by human normal-resting epidermal LC has not yet been demonstrated. In this study, highly sensitive immunostaining techniques, such as immunogold labelling in transmission- and scanning-electron microscopy, were used on freshly isolated, LC-enriched, normal human epidermal cells. Human normal resting epidermal LC were found to be CR3+, since a low but significant number of gold granules labelled the plasma membrane of all the LC observed under transmission-electron microscopy, and all the epidermal cells showing LC morphology as observed by scanning-electron microscopy.