Human immune response to polydimethylsiloxane (silicone): screening studies in a breast implant population

COVID-19 Infection or Buttock Injections? The Dangers of Aesthetics and Socializing During a Pandemic

Introduction

Silicone (polydimethylsiloxane) injections are used for cosmetic augmentation. Their use is associated with life-threatening complications such as acute pneumonitis, alveolar hemorrhage, and acute respiratory distress among others [1,2]. We report a case of a Hispanic woman who developed severe respiratory distress syndrome after gluteal silicone injections.

Case Presentation

A 44-year-old Hispanic female presented to the Emergency Department complaining of progressive dyspnea on exertion for two weeks. Chest imaging revealed patchy bibasilar airspace opacities of peripheral distribution. Labs were significant for leukocytosis, elevated PT, D-dimer, lactate dehydrogenase, and fibrinogen, concerning for COVID-19, however SARS-CoV-2 testing was negative multiple times. The patient later became encephalopathic, hypoxemic, and eventually required intubation. Further history uncovered that the patient had received illicit gluteal silicone injections a few days prior to her onset of symptoms. The patient was diagnosed with silicone embolism syndrome (SES) and initiated on high dose intravenous methylprednisolone [1].

Case Discussion

Patients from lower socioeconomic backgrounds utilize illicit services to receive silicone injections at minimal costs. This leads to dangerous outcomes. The serology and imaging findings observed in our case have similarities to the typical presentation of COVID-19 pneumonia making the initial diagnosis difficult. This case serves as a cautionary tale of the importance of thorough history taking in patients with concern for COVID-19.

Sonoographic Detection of Silicone Breast Implant Rupture

Sonography can be an effective method of evaluating silicone breast implants for intracapsular or extracapsular rupture, and the characteristic findings in cases of extracapsular and intracapsular extravasation of silicone are discussed. Magnetic resonance imaging (MRI) may be slightly more effective than sonography, however, for detecting implant rupture, particularly small intracapsular ruptures.

Silicone and scleroderma revisited

Silicone, a synthetic polymer considered to be a biologically inert substance, is used in a multitude of medical products, the most publicly recognized of which are breast implants. Silicone breast implants have been in use since the early 1960s for cosmetic and reconstructive purposes, and reports of autoimmune disease-like syndromes began appearing in the medical literature soon thereafter. Over the previous year, silicone implants have been suggested as playing a role in a new syndrome that encompasses a wide array of immune-related manifestations, termed ASIA ('Autoimmune Syndrome Induced by Adjuvant'). Scleroderma, a relatively rare connective tissue disease with skin manifestations and systemic effects, has also been described in association with silicone implantation and rupture. However, epidemiological studies and meta-analyses have failed to corroborate the clinical impression of silicone-induced scleroderma. The following review describes the mechanisms by which silicone may mediate autoimmunity in general, as well as the evidence for causal associations with more specific autoimmune syndromes in general, and scleroderma in particular.

Silicone and autoimmunity

BACKGROUND

Since the 1960s, silicone implants have been successfully used for breast augmentation and reconstruction. However, safety issues regarding the use of silicone have led to a moratorium by the US Food and Drug Administration between 1992 and 2006.

DESIGN

To date, although the moratorium has been removed and women overwhelmingly prefer silicone over saline implants, local and systemic adverse effects still remain a concern.

RESULTS

Silicone-elicited inflammatory fibro-proliferative response and capsular contracture is irrefutable. Studies on silicone breast implants have not supported a relationship to carcinogenesis, whereas that to autoimmunity mainly to nondefined autoimmune phenomena seems very plausible. These silicone-related autoimmune adverse events termed 'siliconosis' are probably limited to a small minority of implanted patients.

CONCLUSIONS

Risk factors, such as characteristic environmental exposure and/or genetic predisposition, still require further elucidation. Similarly to antibacterial agents, texturized implants and Zafirlukast that were found to be beneficial in inhibiting fibro-proliferative response and capsular contracture, elucidating autoimmune-related risk factors might subsequently enable physicians to accurately predict long-term health status of silicone implant recipients.

Silicone breast implantation-induced scleroderma: description of four patients and a critical review of the literature

Since the early 1980s, case reports and case series describe an association between silicon breast implants and the appearance of autoimmune diseases, particularly scleroderma. The publication of those cases led to a large number of studies to investigate this association. The conclusion of those studies is that most probably there has not been an increased incidence of autoimmune diseases in women with silicon breast implants. Nevertheless, the US Food and Drug Administration determined that silicone gel breast implants are not completely safe, only that they are ‘reasonably safe.’ The debate continues regarding this association. In this article we present new cases of silicon breast implant-induced scleroderma and review the literature on this subject. Lupus (2009) 18, 1226—1232.

Serum proteins and paraproteins in women with silicone implants and connective tissue disease: a case-control study

Prior studies have suggested abnormalities of serum proteins, including paraproteins, in women with silicone implants but did not control for the presence of connective-tissue disease (CTD). This retrospective case–control study, performed in tertiary-care academic centers, assessed possible alterations of serum proteins, including paraproteins, in such a population. Seventy-four women with silicone implants who subsequently developed CTD, and 74 age-matched and CTD-matched women without silicone implants, were assessed in the primary study; other groups were used for additional comparisons. Routine serum protein determinations and high-sensitivity protein electrophoresis and immunofixation electrophoresis were performed for detection of paraproteins. Women with silicone implants, either with or without CTD, had significantly lower serum total protein and α₁-globulin, α₂-globulin, β-globulin, γ-globulin, and IgG levels compared with those without silicone implants. There was no significant difference, however, in the frequency of paraproteinemia between women with silicone implants and CTD (9.5%) and age-matched and CTD-matched women without silicone implants (5.4%) (odds ratio, 1.82; 95% confidence interval, 0.51–6.45). Paraprotein isotypes were similar in the two groups, and the clinical characteristics of the 13 women with paraproteinemia were comparable with an independent population of 10 women with silicone breast implants, CTD, and previously diagnosed monoclonal gammopathies. In summary, this first comprehensive study of serum proteins in women with silicone implants and CTD found no substantially increased risk of monoclonal gammopathy. Women with silicone implants, however, had unexpectedly low serum globulin and immunoglobulin levels, with or without the subsequent development of CTD. The causes and clinical implications of these findings require further investigation.

Bilateral areoleor depigmentation after augmentation mammoplasty: a case report and literature search

Breast augmentation is by far one of the most common aesthetic procedures performed by plastic surgeons, and silicone implants are the most common prostheses used. Complications arising from the procedure are broadly categorized as either surgery or prosthesis related. Most of the complications are well known and have been documented, but areolar depigmentation after silicone gel prosthesis has not been reported to date.

The association between silicone implants and both antibodies and autoimmune diseases

Silicones are widely used materials in many fields of medicine and largely are believed to be biologically inert. However, some investigators have reported that silicone implants are associated with an increased incidence of autoimmune disorders. In this study, we evaluated the capsular tissue of silicone implants and the sera of implant patients and controls for antisilicone antibodies and nonspecific immunoglobulins (IgG, IgA, IgM, and IgE). Our study group included 15 patients (eight men and seven women) undergoing reconstructive procedures for burn scars, in whom we used silicone implants, and 15 sex-matched controls undergoing reconstructive surgery for burn scars without using silicone implants. By immunofluorescence, we discovered strong capsular binding of IgG and weak capsular binding of IgM; antisilicone antibody levels were significantly higher in capsular tissue than elsewhere. Serum IgE also was higher in patient vs control subject sera. In conclusion, silicone materials do lead to an immune response consisting of antisilicone antibodies most evident immediately adjacent to the implant itself.

Setons and serum IgG titers to silicone

PURPOSE

To determine whether exposure to silicone shunts used in refractory glaucomas increases serum IgG binding to silicone and whether this response is associated with shunt-related complications or poor postoperative intraocular pressure control.

METHODS

Sera from 12 patients (13 eyes) who had undergone placement of silicone seton implants were examined for IgG binding to silicone. Patients were monitored postoperatively for the occurrence of complications and intraocular pressure elevation (mean duration of exposure to silicone and follow-up, 25.1 months; range, 2.5-86 months).

RESULTS

The levels of serum IgG binding in 4 of the 12 patients were two standard deviations above the mean for control sera. No patients had titers greater than 46 arbitrary units (AU). Four patients developed shunt-related complications; the serum IgG binding to silicone for their sera ranged from 24 to 46 AU. Serum IgG binding values were not significantly correlated with poor postoperative intraocular pressure control, or with a history of autoimmune disease or malignancy, type of glaucoma, previous intraocular surgery, or chronic uveitis.

CONCLUSIONS

Although elevation of serum IgG binding to silicone may be noted in some patients receiving silicone seton shunts, individual levels do not seem to predict the development of shunt-related complications. Since the number of patients tested, the frequency of elevated IgG binding values, and the complication rate were relatively low in this study, it is difficult to exclude some clinicopathologic correlations. However, the results are in accord with previous studies of silicone ocular devices suggesting that clinically significant reactions to silicone ophthalmic implants must be rare events, and hence do not necessitate altering the use of these important devices.

The immunopathology of siliconosis. History, clinical presentation, and relation to silicosis and the chemistry of silicon and silicone

Recent evidence confirms the fundamental involvement of the human immune system in the reaction to implantation of silicone-based medical devices. An as yet-to-be particularized epitope of many complex substances sharing siloxane structures is presented through the MHC-II apparatus with development and retention of T cell memory. This memory can be tested for in practical terms using one or more forms of silica, which links the immuno-histopathology and autoimmune attributes of "silicosis" with those of "siliconosis." The lesions of siliconosis are typical of those for persistent antigens and delayed, cell mediated hypersensitivity. The basic descriptive pathology of the reaction to silicone has been known since soon after introduction of silicones in medical procedures, with the exception of some details related to the more recent discoveries on the role of cytokines in the immunopathic process. The clinical consequences of siliconosis are common and can be severe in some individuals implanted with silicone devices.

Association of silicone breast implants with immunologic abnormalities: a prospective study

PURPOSE

To study the possible association of silicone-breast-implant exposure and immunologic abnormalities within the Nurses' Health Study, an ongoing prospective cohort study of women.

SUBJECTS AND METHODS

From this cohort, we randomly selected 200 women who had been exposed to silicone breast implants and who had never reported connective tissue diseases during 14 years of follow-up, and 500 age-matched, nonexposed women, including 100 with definite connective tissue diseases validated by medical record review, 100 with at least one symptom of a connective tissue disease, 100 with diabetes, and 200 healthy controls. Assays for antinuclear antibodies (ANA), including anti-dsDNA, anti-ssDNA, anti-Sm/RNP/Ro/La, and anti-Scl-70, rheumatoid factor, immunoglobulins, serum complement, and C-reactive protein level, and anticardiolipin, antithyroglobulin, antithyroid microsomal, and antisilicone antibodies were performed by standard techniques in blood samples collected in 1989 or 1990 before collection of silicone-breast-implant exposure data in 1992.

RESULTS

ANA was positive (> or = 1:40) in 14% of women with silicone breast implants compared with 20% of healthy women (P = 0.11). Rheumatoid factor was positive (> or = 1:40) in 5% of women with silicone breast implants and 2% of healthy women (P = 0.16). Women with silicone breast implants had a significantly higher frequency of anti-ssDNA antibodies than healthy women (41% and 29%, P = 0.012). Duration of implant was associated with a higher frequency of anti-ssDNA antibodies (P = 0.03) but not with ANA or rheumatoid factor. No other significant differences in the frequencies of autoantibodies were observed in silicone breast implant-exposed women. Antisilicone antibodies were not found in any sample.

CONCLUSION

We found no increased frequency of any immunologic abnormalities in women exposed to silicone breast implants, except for anti-ssDNA, which has unknown clinical relevance.

The effect of silicone ocular surgical devices on serum IgG binding to silicones

PURPOSE

To determine whether silicone materials used in retinal detachment repair and cataract surgery increase serum IgG binding to silicone and identify correlations with complications of ocular surgery.

METHODS

Serum from 49 patients who had ocular surgery using silicone materials was examined. Patient groups included scleral buckling (n = 25), silicone oil tamponade (n = 3), scleral buckling and silicone oil tamponade (n = 9), and silicone lens implants after cataract extraction (n = 12). Convalescent samples for all patients and preoperative samples from 19 patients (18 scleral buckling and one silicone oil tamponade) were examined. Postoperative complications were monitored for up to 108 months (mean, 10.7 months; mode, 1.5 months; range, 1 to 108 months). Samples were evaluated for the extent of IgG binding to silicones using a micromodification of a previously described enzyme-linked immunosorbent assay method.

RESULTS

In 19 patients, IgG binding levels in preoperative samples were 21 arbitrary units (AU) or less. Of the 25 buckling patients, one developed complications; however, in all patients the postoperative levels of IgG binding to silicone were low (2.2 to 20.0 AU). Although four silicone lens patients developed mild complications, none displayed postoperative IgG binding levels of greater than 20 AU. Three patients who underwent both scleral buckling and silicone oil tamponade developed complications; one of these patients, who was also noted to have systemic connective tissue disease, had a significant elevation in postoperative serum IgG binding to silicone.

CONCLUSIONS

Statistically significant elevations of serum IgG binding to silicone were noted postoperatively in only one patient who had a systemic connective tissue disease. The complication rate and frequency of enhanced serum IgG binding to silicone was low, making correlations to surgical complications difficult. Examination of matched samples suggested that if ocular exposure to silicone implants enhances the level of serum IgG binding to silicones, it must be a rare event that should not alter the clinical use of these important devices.

The non-specific binding of immunoglobulins to silicone implant materials: the lack of a detectable silicone specific antibody

Recent studies have suggested that anti-silicone antibodies develop in patients implanted with silicone materials. The majority of these studies have utilized enzyme-linked immunosorbent assay (ELISA) methodology with a silicone material substrate as a means to detect the presence of the anti-silicone antibody. The current studies were undertaken to determine whether the binding of IgG to a silicone substrate was consistent with an antigen-specific antibody interaction or the result of non-specific hydrophobic interactions. While significant differences were detected in serum from silicone antibody "positive" and "negative" patients when the ELISA was conducted using a phosphate buffered saline (PBS)-0.05% Tween 20 (Tween) blocking system, the difference in the responses was attenuated when protein blocking systems were used or when incubation times were decreased. Furthermore, ELISA studies, using purified mouse and human IgG, demonstrated a concentration-dependent binding of IgG to silicone elastomer substrate which was also attenuated when a protein blocking system was used in lieu of Tween. In controlled animals studies in which female B6C3F1 mice were implanted with silicone gel or silicone elastomer for 180 days, no difference was observed between the implanted animals and the PBS control animals with respect to binding of IgG to the silicone substrate. Similar studies in female Fischer 344 rats implanted with silicone gel for 84 days also failed to demonstrate the presence of anti-silicone antibody. Collectively, the results suggest that the binding of IgG to silicone implant materials is non-specific in nature, consistent with the well-recognized interactions between hydrophobic molecules (IgGs) and hydrophobic surfaces (silicones) in an aqueous-based system.

Breast implants and cancer

BACKGROUND

Although silicone breast implants have been linked to various short-term complications, less is known about their long-range effects. Most attention has focused on connective tissue disorders, but the range of immunologic disturbances observed in women with implants suggests that consideration also be given to other chronic diseases, including cancer. The greatest attention has focused on breast cancer, given clinical reports suggesting an association and observations that mammographic visualization is deterred by implants. Findings from epidemiologic studies, however, actually suggest that breast cancer risk might be reduced among women with implants, although the biologic mechanism remains undefined. In addition, most studies do not suggest that women with breast implants have more advanced breast cancer at diagnosis or a worse prognosis than those without implants. The majority of studies have focused on women who received implants for cosmetic reasons, with little previous investigation of women who received implants for breast reconstruction following cancer surgery. In terms of other cancers, animal as well as clinical data suggest potential risks of sarcomas and hematologic cancers, including multiple myeloma. The risk of these cancers has not yet been adequately addressed by epidemiologic studies, although several ongoing studies should provide insights. It will be important for studies to consider effects of other lifestyle factors as well as to analyze relationships according to duration of implantation, a demonstrated determinant of implant deterioration. In addition, consideration should be given to type of implant, including implants with polyurethane foam covers, which can leak toluene diamine, a demonstrated carcinogen in animals.

Cellular immune reactivities in women with silicone breast implants: a preliminary investigation

BACKGROUND

Surgical implantation of silicone breast prostheses has been conducted and considered safe for over 30 years. Some implant recipients, however, complain of a group of symptoms similar to those observed in connective tissue disorders, rheumatoid arthritis, systemic lupus erythematosus, or polymyositis. To date, immunologic sequelae have not been confirmed and remain controversial.

OBJECTIVE

To examine an autoimmune-like basis for the "silicone associated disease" reported by some women with silicone breast prostheses.

METHODS

Proliferative responses of peripheral blood mononuclear cells against a panel of control and connective tissue proteins and to compounds common to silicone prostheses were measured in 26 women who received silicone breast implants (with implants in place an average of 166.4 [standard deviation (SD) 58.3] months), and 23 age-matched and sex-matched healthy controls.

RESULTS

The frequency and intensity of cellular immune responses against collagen I, collagen III, fibrinogen, and fibronectin were significantly increased in silicone breast implant recipients versus controls. In implant subjects, the highest frequency of immune reactivity was directed against collagen I (11/26, 42%) with collagen III being the most immunostimulatory self-antigen with a mean stimulation index (SI) of 8.2 [95% confidence interval (95% CI) 3.2]. In addition, 10/26 (39%) of the implant recipients responded to more than one of the connective tissue antigens versus 0/23 (0%, P = .0007) healthy controls. Immunologic reactivities to other antigens, including silicone-based compounds, were remarkably similar.

CONCLUSIONS

The identification of self-reactivity towards these connective tissue antigens may provide important information for attempts at associating silicone breast implants with disease.

Comparative studies on the interaction of proteins with a polydimethylsiloxane elastomer. I. Monolayer protein capture capacity (PCC) as a function of protein pl, buffer pH and buffer ionic strength

Polydimethylsiloxane (PEP) is widely used in medical prostheses and therefore is in contact with plasma and secretory proteins. Two pair of globular proteins, lactoferrin (Lf) and transferrin (Trf), and bovine IgG1 and IgG2a, which differ substantially between pair members in their pl, were used to study the interaction of a PEP widely used in breast implants and soluble protein. Studies were done using iodinated proteins over a concentration range that resulted in an apparent protein monolayer. Secondary incubations with dilute protein solutions were needed to form the monolayer on PEP, possibly as a consequence of micro air bubbles trapped on its highly textured surface as shown by atomic force microscopy. Immunoassay quality polystyrene microtiter wells were used as controls. Adsorption studies were routinely performed at pH 4, 7 and 10 and at ionic strengths corresponding to 0.95, 9.5 and 90.0 mS. The protein capture capacity (PCC) of PEP for Lf and Trf was optimal at physiological pH and ionic strength and comparable under these conditions to that of Immulon 2 (Imm 2) microtiter wells. While increasing the ionic strength and pH further increases the PCC of Imm 2 for Lf and Trf, this markedly lowered the PCC of PEP for these proteins suggesting that initial polar interactions may precede subsequent hydrophobic bonding to PEP. This was tested using a hydrophilic variant of PEP, which when tested in a 90.0 mS buffer, showed a > five-fold lower PCC at neutral and alkaline pH. The greatly reduced PCC of the hydrophilic variant might also suggest that hydrophilic variants of silicone would be more biocompatible than those currently used. The PCC of PEP for the IgGs was less than that of Imm 2 but still optimal at physiological conditions. Consistent with the data on Lf/Trf, PCC progressively decreased with increasing ionic strength at alkaline pH. Differences in pl between the protein pairs had only a marginal effect on the PCC of PEP. Monolayer adsorption on both PEP and Imm 2 was slowly reversible and greater in the presence of free ligand (< 2% in 16 h) suggesting that the process follows Mass Law principles. However, even in the presence of non-ionic detergent and free ligand, 85-90% remained bound on either surface. Thus, desorption of proteins in the monolayer should not complicate subsequent immunochemical studies conducted on adsorbed monolayers.

Determining the safety of the silicone envelope: in search of a silicone antibody

In the controversy surrounding breast implants, one of the crucial questions is whether patients ca form antibodies directed against the silicone shell of the implant. If this were the case, implications for current breast implant development, indeed, for all silicone medical devices, are far-reaching. To evaluate this hypothesis, sera from 18 patients who had tissue expanders and 15 control patients who had no silicone implant exposure were tested retrospectively for antibodies to the silicone using an enzyme-linked immunosorbent assay previously documented as a case report in the literature. Contrary to previous studies, no significant difference in antibody levels was found between test subjects and the controls. Additionally, this enzyme-linked immunosorbent assay for silicone antibodies was poorly reproducible. This study calls into question the existence of specific antibodies to the silicone shell. It also provides further data that the enzyme-linked immunosorbent assay may not be reliable as a silicone antibody test.

Protein interactions with particulate Teflon: implications for the foreign body response

PURPOSE

This study examined the nature of protein interactions with particulate polytetrafluoroethylene (PTFE, Teflon) to elucidate possible mechanisms involved in the foreign body response directed against failed Proplast/Teflon implants.

MATERIALS AND METHODS

Fifty milligrams PTFE prepared to particle sizes ranging from < 32 microns to > 300 microns was incubated with newborn bovine serum. The total amount of protein adsorbed to the PTFE particles was determined using a standard colorimetric assay. The structural and functional integrity of the proteins adsorbed to PTFE was also examined. For these studies, xanthine oxidase was substituted for serum, and the enzymatic activity of xanthine oxidase adsorbed to PTFE was determined. Finally, primary interactions between protein and PTFE particles were assessed in experiments using water, 2 or 8 mol/L urea, 1 mol/L Nacl, or 1% sodium dodecyl sulfate in an attempt to dissociate bound protein from the surfaces of PTFE particles.

RESULTS

Serum proteins bind almost instantly to the surface of PTFE particles. The effective surface area of PTFE increases dramatically with reduction of the material to small particles, as does the total amount of protein adsorbed by the particulate PTFE. Proteins bind to PTFE principally by hydrophobic interactions, and their three-dimensional structure is significantly perturbed by this interaction. In the case of xanthine oxidase, adsorption to PTFE distorts protein structure to the extent that biologic activity is eliminated.

CONCLUSIONS

The amount of serum protein adsorbed to PTFE particles varies inversely with particle size for a constant mass of material. It is believed that the foreign body response directed against this material is related to the amount and relative distortion of proteins adsorbed to its surface. If so, it appears that reduction of an implant to small particles (typically 50 micron or less) will dramatically increase the biologic signal to local cell populations. Thus, the severity of the biologic response to PTFE debris may be dependent largely on the size of the debris particles.

Silicate antibodies in women with silicone breast implants: development of an assay for detection of humoral immunity

Silicon, in the form of sodium silicate (Na2SiO3), adsorbed onto bovine serum albumin (BSA)-precoated plates served as the solid-phase antigen in an enzyme immunoassay to detect silicate-reactive antibodies in the plasma of 40 symptomatic women with silicone breast implants, 91 asymptomatic women with silicone breast implants, 50 healthy control women, and 52 women with rheumatic diseases and without silicone breast implants, Silicate-reactive antibodies of immunoglobulin G (IgG) or IgM isotypes were detected in the plasma of 30% (12 of 40) of the symptomatic women with silicone breast implants; 9% (8 of 91) of the asymptomatic women with silicone breast implants; 5% (1 of 20) of the women without implants who had systemic lupus erythematosus; and 0% (0 of 32) of the women without implants who had either Sjögren syndrome, scleroderma, or rheumatoid arthritis. Only 2% (1 of 50) of the sera from the healthy control women contained silicate-reactive antibodies. Preincubation of sera with silicate and eight other metal compounds (including SiO2) demonstrated that the IgG and IgM antibodies bound specifically to silicate, because preincubation with Na2SiO3 inhibited more than 90% of the activity, whereas CrO3, Li2SO4, MgSO4, NiSO4, HgCl2, ZrOCl2, BeSO4, and SiO2 failed to inhibit the IgG or IgM antibody binding to the silicate-BSA plates. Furthermore, the F(ab')2 portion and not the Fc portion of the silicate-reactive IgG was reactive with BSA-bound silicate in the enzyme immunoassay. The assay for silicate-reactive antibodies was quantified by assigning arbitrary units to a standard curve composed of serial twofold dilutions of high-positive (ten times higher than the cutoff) silicate antibody sera. This novel assay is a useful method for detecting and quantifying humoral immune response to silicate.

Silicone binding immunoglobulins in human sera

We have evaluated two recently published test procedures for demonstrating antibodies to silicone. Positive control serum samples provided to us by the original authors were positive in our hands, using the methods described. However, serum samples from patients with certain connective tissue diseases but no history of silicone implants were also positive. The question of silicone-specific antibodies remains unresolved.

Lymphocyte response to silica among offspring of silicone breast implant recipients

The current study evaluated immune response to silicon dioxide in children born to women with silicone breast implants. In part one of the study, the T lymphocytes of 21 of 24 such children were significantly stimulated by silicon dioxide (silica). Part two consisted of eleven children, four born preimplantation and seven born postimplantation. None of the preimplant offspring showed T cell responses to silica; five of the seven postimplant children were positive for T cell memory for silica. Part three was a blinded study based on statistically significant differences in T cell stimulation with silicon dioxide between postimplant children and controls. These findings indicate a common immune reaction, that of T cell memory, occurs in mothers and their children born after exposure to silicone mammary implants placed prior to pregnancy. Since not all such children were breast fed the result favors transplacental passage of immunogens such as silicone oligomers or through maternofetal cellular traffic.

Physicochemical and immunological basis of silicone pathophysiology

Silicones, model biomaterials with almost ubiquitous applications, are the focus of a contentious debate. In this review, we will consider both established physicochemical phenomena and immunological phenomena; and then consider the human clinical phenomena that relate directly to them. We will explore the two competing theories of the biological activity of silicones, and we will discuss the weaknesses in the various arguments that silicone is inert. We conclude that from a pathophysiological perspective, silicones should be expected to be bioactive materials and that the physicochemical and immunological data at the experimental level are compelling.

Novel anti-silicone surface-associated antigen antibodies (anti-SSAA(x)) may help differentiate symptomatic patients with silicone breast implants from patients with classical rheumatological disease

The frequency of novel autoreactive antibodies to silicone surface associated antigens (anti-SSAA(x)) was measured in healthy control patients, symptomatic patients with breast implants, asymptomatic patients with breast implants, and control patients with classical rheumatological diseases. The frequencies of elevated anti-SSAA(x) antibodies in 310 symptomatic breast implant patients were 17.4% anti-SSAA(fn), 12.9% anti-SSAA(col1), and 7.4% anti-SSAA(col3) and 7.1% anti-SSAA(fbgn) [Normal (n = 173) = 0.6% for all four tests] (p < .005). In 11 asymptomatic breast implant patients, the frequencies of elevated values for the same anti-SSAA's were 0%, 9%, 0%, and 0% respectively, while in 50 patients with rheumatoid arthritis, the frequencies were 4%, 0%, 6% and 2% respectively. The anti-SSAA(x) profile for symptomatic patients with breast implants was different than the profile for control healthy patients (p < .005 on all eight tests) but differed significantly by two measures, anti-SSAA(fbgn) and anti-SSAA(col3), from the profile for the 19 patients with systemic lupus erythematosus. We conclude that anti-SSAA(x) antibodies levels in symptomatic patients with breast implants are elevated, that the antibodies are associated with symptoms, and that they differ both qualitatively and quantitatively from healthy controls, asymptomatic patients with breast implants, and symptomatic patients with classical rheumatological diseases.

Laboratory studies in breast implant patients: ANA positivity, gammaglobulin levels, and other autoantibodies

Silicone polymers when used in augmentation prosthesis in breast surgery have been associated in the medical literature with various systemic clinical manifestations and abnormal laboratory testing suggestive of an atypical autoimmune disease. The most frequently cited abnormal test result is the antinuclear antibody. The literature regarding this test is reviewed in general, and then specific previous studies analyzed. The present study then compares the rate of positive antinuclear antibody tests in a case series of 3380 breast implant recipients with historical normal controls, and finds a six-fold increase in relative risk of a positive test. Analysis of the data show that this increased tendency is at least partially a function of duration of implant exposure to a significant degree (p < 0.001), and the same data shows it is not patient age related. Possible explanations of this phenomenon are discussed, including animal studies suggesting that silicone serves as an adjuvant, and therefore might have an effect on immune tolerance in the subject population.

Self-reported signs and symptoms in breast implant patients with novel antibodies to silicone surface associated antigens [anti-SSAA(x)]

In research animals, the immune adjuvant activity of silicone in eliciting antibodies to associated protein antigens is now well established. In humans, the immune adjuvant activity of silicone remains controversial. Clusters of data from various research groups are beginning to define the boundary conditions for future large epidemiological studies. In that spirit, this manuscript reports pilot clinical data from a serological study conducted 3 years ago and reported previously in this journal. Sera from a self-selected symptomatic population of patients with breast implants were assayed for elevated concentrations of antibodies showing binding avidity to silicone surface associated antigens [anti-SSAA(x)]. In that study of 249 patients, two distinct statistically significant subgroups were identified on the basis of the serological assay alone: patients without any elevated anti-SSAA(x) (negative) and patients with elevated anti-SSAA(x) (positive) (p < 0.001). In this study, a clinical survey returned by 226 of those patients was correlated with the previously acquired serological findings. The 11 most common clinical complaints reported by the 199 anti-SSAA(x) negative patients and by the 27 anti-SSAA(x) positive were compared and their frequencies analyzed. The 199 anti-SSAA(x) negative patients, as a group, showed a lower frequency of a variety of signs and symptoms compared to the 27 anti-SSAA(x) positive patients. Statistically significant differences were seen in three of the symptoms: fever, foot pain, and sleep disturbance (p < 0.05). In addition, the syndrome of fever in the absence of local chest pain was a significantly associated with anti-SSAA(x) positivity (p < 0.001).

Inflammatory intermediates produced by tissues encasing silicone breast prostheses

Silicone prostheses, when implanted within the soft tissues of the breast, evoke an inflammatory reaction. In response to silicone exposure, inflammatory mediator production by individual cells has been observed in various experimental studies. In this study, inflammatory mediator production by periprosthetic tissues (whole organ) was measured. The mediator levels were correlated with both the tissue histopathology of the periprosthetic capsules and the clinical symptoms noted by each patient. Tissue surrounding breast implants removed at surgery from ten women (average age and implant duration 40 and 7 years respectively) was cultured in vitro for 24 hours. Control tissues consisting of (a) augmentation mammaplasty skin scars from eight additional patients and (b) knee synovium from seven orthopedic surgery patients with arthritis undergoing primary joint arthroplasty were similarly cultured. The mediators [interleukin-2 (IL-2), tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and prostaglandin E2 (PGE2)] liberated into the culture media were measured by an enzyme linked immunosorbent assay. When compared to controls, the mediator levels of IL-6 and TNF-alpha were substantially greater, although IL-2 and PGE2 were lower. Levels varied greatly from patient to patient: in pg/ml per 10 g tissue, IL-2 ranged from 10 to over 1,000; TNF-alpha from 100 to 1,000; IL-6 from 100 to 1,000,000; and PGE2 from 100 to 10,000. The correlation between TNF-alpha and PGE2 levels was .5 between IL-6 and PGE2 was .6, and between IL-6 and TNF-alpha was .77. The correlation between TNF-alpha and IL-6 was statistically significant at a p-value less than .01. Elevated levels of TNF-alpha production were associated with an increased number of macrophages and overall tissue cellularity (p < .05). No significant relationship was observed between mediator production and clinical symptoms. We conclude that overall cellularity, specifically macrophages, in the periprosthetic capsule may lead to TNF-alpha production but that cytokine production by periprosthetic tissues alone is not a predictor of clinical symptomatology in patients with silicone breast prostheses.

Immunotoxicity of silicone: implications of oxidant balance towards adjuvant activity

A variety of mechanisms can be proposed to explain the potential effects of silicone and silicone by-products on the immune response. In this paper, we discuss information on the chemistry of silicon and silicone gels/elastomers, and the manufacture of silicone breast implants as they pertain to the bioreactivity of silicone. Moreover, with reference to silicone-mediated human adjuvant disease, an overview of experimental adjuvant-induced arthritis is presented; comparisons with graft-versus-host disease and chemically induced autoimmunity then follow. Particular attention is paid to similarities in the characteristics of silicone and classic lipid adjuvants. For example, macrophage activation is presumed to be a central event in silicone-induced autoimmunity. Since those genes uniquely expressed in macrophages activated by plastic adherence are similar to those induced by lipopolysaccharide, adherence to silicone rubber may initiate an inflammatory response by the same mechanism. Macrophage effects would also include the erosion of implants through the generation of oxidants and localized pH changes. The degradation products of silicone are also implicated in the adjuvant effects of silicone implants. There is evidence to suggest that oxidants produced by inflammatory cells preferentially inactivate CD8+ suppressor T cells. This could then lead to an inflammatory state, perhaps through oxidant-induced transcription factors such as NF-kB, resulting in a long-term pro-oxidant imbalance that manifests itself as a breakdown in immunological self-tolerance. The authors hypothesize that autoreactivity following oxidant stress evolved to enhance inflammatory repair mechanisms after tissue, cell or molecular damage by oxidants.

Autoimmune connective tissue disease and connective tissue disease-like illnesses after silicone gel augmentation mammoplasty

Since first reported in 1982, published anecdotal reports have appeared with increasing frequency of patients in whom autoimmune connective tissue diseases developed after mammary augmentation with silicone gel-filled elastomer envelope-type prostheses. Although scleroderma has been reported most often, other diagnoses have included systemic lupus erythematosus, rheumatoid arthritis, Sjögren's syndrome, and mixed connective tissue disease. Other patients have ill-defined connective tissue-like illnesses often referred to as "human adjuvant disease." The occurrence of dermatomyositis and polymyositis after silicone breast implants appears to be infrequent. We report two new cases of dermatomyositis after silicone exposure. In addition, a comprehensive review of the literature pertaining to rheumatic disease and silicone gel augmentation mammoplasty is presented to provide some perspective on this highly complicated and controversial subject.

Clinical findings in symptomatic women with silicone breast implants

We report the clinical findings in a series of women with silicone breast implants (SBI) and rheumatic disease. These findings represent the first 50 patients seen at the University of South Florida Medical Clinic between March 1977 and January 1991. The average age was 44 years with a range of 30 to 66 years. The most common clinical findings included chronic fatigue, muscle pain, joint pain, joint swelling, and lymphadenopathy. Seventeen women with an average Steinbrocker functional class of 1.8 decided not to remove the implants. An average of 14 months later, follow-up showed no change in their condition. Thirty-three women, with an average functional class of 2.5 underwent implant removal. Twelve of the 33 had documented implant rupture. During an average follow-up of 22 months after implant removal, 24 women improved clinically, 8 did not change, and 1 worsened. We believe this series supports a relationship between silicone breast implants and rheumatic disease signs and symptoms. Although this report is not a definitive epidemiological study, findings suggest that physicians should inform women about the possible benefit of implant removal.

Current status of silicone gel breast implants

There are currently three main areas of concern regarding the safety of silicone gel implants: implant failure; a potential link to autoimmune connective tissue disease; and a possible link to breast cancer. All silicone gel implants ‘bleed’ small levels of silicone. In addition, silicone gel implants appear to fail (leak or rupture) with time. Most implants in place for less than seven years appear to be intact. It appears that many silicone gel implants implanted for over seven years are probably ruptured or leaking. Implant failure may occur simply from deterioration. Implants can also rupture following closed capsulotomy. Mammography and ultrasound studies are generally not helpful in predicting implant failure. Magnetic resonance imaging (MRI) studies appear to be useful, but the ‘breast coil’ necessary to perform these studies is not currently available in most MRI units in Canada. The significance of implant failure is not known. There is a growing (but unproven) concern that immunological sensitization to silicone could develop in women with silicone gel implants. An extensive review of all clinical and immunological studies in the current literature has failed to demonstrate any conclusive link between silicone gel implants (whether intact or nonintact) and the development of autoimmune connective tissue disease or other disease process. However, large scale epidemiological studies remain to be done. Several large studies have proven that there is no relationship between silicone gel implants and the development of breast cancer.