Immunomodulation of Human Skin Cells by Extracts of the Scabies Mite, Sarcoptes scabiei

by Mullins, Jeremi Stevan

Sarcoptes scabiei infests its host through burrowing into the stratum corneum layer of skin. Keratinocytes and fibroblasts responding to the burrowing mite(s) and/or mite products produce inflammatory and immune activating cytokines and chemokines. The purpose of this study was to determine if an extract of S. scabiei can modulate cytokine and chemokine expression from keratinocytes and fibroblasts in vitro. Normal human keratinocytes and fibroblasts were exposed to an extract of S. scabiei var. canis with or without various pro-inflammatory stimuli. Cytokine and chemokine expression were measured by enzyme-linked immunosorbent assay (ELISA). Scabies extract increased expression of interleukin-6 (IL-6), growth-related oncogene-? (GRO-?), transforming growth factor-? (TGF-?), and cutaneous T-cell attracting chemokine (CTACK) by keratinocytes. In contrast, scabies extract decreased expression of interleukin-8 (IL-8) by keratinocytes. In comparison, scabies extract increased expression of IL-6 and granulocyte-colony stimulating factor (G-CSF) by fibroblasts. In contrast, scabies extract decreased expression of granulocyte/macrophage-colony stimulating factor (GM-CSF) and IL-8 by fibroblasts. These findings demonstrate that S. scabiei can modulate cytokine and chemokine expression by human keratinocytes and fibroblasts.