Differential Gene Expression of Cutaneous Cells Upon Exposure to Staphylococcal Enterotoxin B (SEB) Superantigen

Abstract

Staphylococcus aureus, a gram‐positive bacterium initiates lesions through the production of pyrogenic toxins termed Staphylococcal enterotoxins (SEA‐J), and toxic shock syndrome toxin‐1 (TSST‐1) causing staphylococcal food poisoning and toxic shock syndrome. SEs are prototypical superantigens (sAgs), which trigger massive V‐beta specific T cell proliferation without the need for internalization, processing, or presentation resulting in elevated serum cytokine levels. The presence and the detectability of these sAgs in the sera of burn victims is not clearly understood. We have detected circulating SEA, SEB and TSST‐1 toxins among 20% of the burn victims. In this study, we aim to elucidate the chronology of intoxication along with in vitro studies to better understand the potential effects of this SEB toxin on skin cells. Primary cultures of human keratinocytes, melanocytes, dermal vascular endothelial cells and dermal fibrobalsts were grown and treated with varying doses of SEB for different lengths of time. RNA was extracted by trizol method and oligonucleotide microarray was performed. Feature extraction and statistical analysis show that genes encoding negative acute phase response proteins, oxidative stress response, NFκB signalling, Anti‐apoptosis were highly upregulated and genes responsible for death receptor signalling, endothelin‐1 signalling, growth hormone signalling were significantly downregulated. The objective of this study is to elucidate the pathogenesis of SEB intoxication in skin cells and thereby help with new treatment strategies in wound healing.We extend our heartfelt thanks to Washington Hospital ct Res Fund and Fire Fighters Burn res for their support