Effects of Silicone Breast Implants on Human Cell Types In Vitro: A Closer Look on Host and Implant

BACKGROUND: Silicone (gel) breast implants (SBI) are used world-wide for breast augmentation, and reconstruction or to correct breast deformities. They consist of two compounds: an elastomer silicone shell (envelope) and a silicone gel filler (core). Breast Implant Illness (BII) is a term used for women with SBI, who suffer from various of symptoms including myalgia, arthralgia, fatigue, fever, dry eyes and/or dry mouth (sicca), as well as cognitive disturbances, which are rated by these woman as response to SBI. The pathogenesis of these adverse effects as well as the histocompatibility and the SBI-cell interaction of silicone and its surrounding tissue (implant-host tissue interface) is a subject of current research. The main purpose of this review is to provide an overview of the current knowledge regarding the effects of silicone (gel and elastomer surfaces) of a SBI on different human cell types from experimental - in vitro - models. METHODS: A comprehensive research was conducted by two independent reviewers in March and July of 2020 in the PubMed, MEDLINE, and Cochrane databases. RESULTS: A number of 1328 articles on this topic were initially identified, of which 62 could be finally included an analysed in this review. CONCLUSION: SBI may lead to a physiologic pro-inflammatory and foreign body host response with fibrous encapsulation accompanied by a disturbed Th17/Treg balance and IL-17 production. No causal relationship is known for systemic symptoms and/or autoimmune outcomes in the context of BII. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.