Extracts of scabies mites (Sarcoptidae: Sarcoptes scabiei) modulate cytokine expression by human peripheral blood mononuclear cells and dendritic cells.
We performed a series of experiments to determine if human peripheral blood mononuclear cells (PBMCs) from a healthy donor and dendritic cells (NHDCs) derived from these PBMCs reacted to molecules in a scabies extract. PBMCs extravasate from the circulatory system and enter tissues such as scabietic lesions, where monocytes become macrophages. Cells were cultured in medium alone or medium containing 50 microg/ml of Sarcoptes scabiei (SS) extract, 50 ng/ml E. coli lipopolysaccharide (LPS), or SS + LPS together. Supernatants were collected and assayed by enzyme-linked immunosorbent assay (ELISA) for specific cytokines. PBMCs stimulated with SS or LPS exhibited moderately upregulated production of interleukin (IL)-1beta and huge increases in secretions of IL-6, IL-8 and TNF-alpha. Cells co-stimulated with both SS and LPS generally secreted more of these cytokines than cells stimulated with either SS or LPS alone. LPS induced a small amount of IL-1alpha secretion, whereas SS did not, and neither additive resulted in the production of IL-10. NHDCs did not produce IL-1alpha, IL-1beta, IL-6, IL-8, or IL-10 in response to stimulation with SS. These cells did produce IL-6, IL-8, and tumor necrosis factor (TNF)-alpha in response to LPS. When cells were co-stimulated with both LPS and SS, the production of IL-6 and IL-8 was significantly reduced compared with the levels secreted after LPS stimulation alone. These studies show that molecules in a whole body extract of S. scabiei modulate the function of PBMCs (probably monocytes) and dendritic cells.
Department of Biological Sciences, Wright State University, Dayton, OH 45435-0001, USA. larry.arlian@wright.edu
Larry G
LG
Arlian
Marjorie S
MS
Morgan
Jacqueline S
JS
Neal
D000818:Animals; D016207:Cytokines / Q000235:genetics*; D003713:Dendritic Cells / Q000187:drug effects / Q000276:immunology*; D004357:Drug Synergism; D004926:Escherichia coli / Q000276:immunology; D005786:Gene Expression Regulation / Q000276:immunology; D006801:Humans; D066298:In Vitro Techniques; D007378:Interleukins / Q000235:genetics; D008070:Lipopolysaccharides / Q000494:pharmacology; D008214:Lymphocytes / Q000187:drug effects / Q000276:immunology*; D012520:Sarcoptes scabiei / Q000737:chemistry*; D014020:Tissue Extracts / Q000494:pharmacology*
D016207:Cytokines; D007378:Interleukins; D008070:Lipopolysaccharides; D014020:Tissue Extracts