title: Silicone nanoparticles do not induce immune responses by naïve human peripheral blood mononuclear cells:  implications in breast implants.
abstract: BACKGROUND
  Several studies have reported adverse immunological effects of silicone due to their ability to induce proinflammatory molecules, such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). In recent years, use of nanoparticles has been under fast development for therapeutic drug targeting, diagnostic imaging, and immune response in various fields of nanomedicine. The authors hypothesize that immune responses induced by in vivo use of silicone materials can be reduced or eliminated by the use of nanosilicone.
  
  
  METHODS
  Peripheral blood mononuclear cells obtained from naïve normal subjects were cultured with different concentrations of silicone nanoparticles and microparticles for 24 hours. The culture supernatants were quantitated for TNF-α, IL-6, and interferon-γ (IFN-γ) secretion by enzyme-linked immunosorbent assay. The pellets were used for specific IL-6, TNF-α, and IFN-γ gene expression by real-time polymerase chain reaction, respectively. Cytotoxicity was evaluated by XTT viability assay. Results were compared between silicone nanoparticles and microparticles and untreated controls.
  
  
  RESULTS
  Silicone nanoparticles up to 100 μg/ml did not induce any detectable levels of specific TNF-α, IFN-γ, and IL-6 gene expression and protein production and the results were comparable to those for untreated controls. Silicone microparticles at 100 μg/ml, however, significantly induced the production and gene expression of TNF-α, IL-6, and IFN-γ by peripheral blood mononuclear cells. XTT viability assay showed that silicone nanoparticles or microparticles, even at the highest concentration used, were not cytotoxic to cells.
  
  
  CONCLUSIONS
  The results suggest that silicone nanoparticles can be engineered to avoid immune recognition and subsequent silicone microparticle-related adverse effects and thus may be of therapeutic significance in the cosmetic industry, plastic surgery, and aesthetic medicine.
authors: Saginaw, Mich.; and Miami, Fla. From the Department of Surgery, Synergy Medical Center; and the Department of Immunology, Institute of Neuro-Immune Pharmacology, Herbert Wertheim College of Medicine, Florida International University.
authors: Narayanan
authors: N
authors: Nair
authors: Sudheesh
authors: S
authors: Pilakka-Kanthikeel
authors: Zainulabedin
authors: Z
authors: Saiyed
authors: Adriana
authors: A
authors: Yndart
authors: Madhavan
authors: M
authors: Nair
mesh_terms: D018427:Breast Implants; D016207:Cytokines / Q000096:biosynthesis / Q000187:drug effects*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005786:Gene Expression Regulation; D006801:Humans; D007111:Immunity, Cellular; D007963:Leukocytes, Mononuclear / Q000276:immunology* / Q000378:metabolism; D016462:Mammaplasty / Q000379:methods; D053758:Nanoparticles; D012333:RNA, Messenger / Q000235:genetics*; D060888:Real-Time Polymerase Chain Reaction; D012828:Silicones
chemical_list: D016207:Cytokines; D012333:RNA, Messenger; D012828:Silicones