Silicone-induced modulation of natural killer cell activity

Area of Science:

• Immunotoxicology
• Biomaterials Science
• Cancer Immunology

Background:

• Growing concerns about silicone gel mammary implants' immune effects necessitate research into silicone material's biological activity.
• Previous studies have shown varied immunological responses to medical implants, highlighting the need for specific component analysis.

Purpose of the Study:

• To evaluate the immunotoxicological effects of key components of mammary gel prostheses.
• To assess the impact of silicone gel implantation on natural killer (NK) cell activity and host resistance in animal models.

Main Methods:

• Subcutaneous implantation of polydimethylsiloxane fluid, silicone gel, elastomer shell, and polyurethane cover in B6C3F1 mice and Fischer 344 rats for varying durations.
• Measurement of natural killer (NK) cell activity and assessment of host resistance to B16F10 melanoma.
• Administration of anti-asialo GM1 and polyinosinic:polycytidylic acid to modulate NK cell activity.

Main Results:

• Silicone gel implantation significantly decreased basal and augmented natural killer (NK) cell activity in both mice and rats, though responses were variable.
• Despite NK cell suppression, host resistance to B16F10 melanoma in mice remained unaltered.
• Gel-implanted rats showed a suppressed response to NK cell augmentation compared to controls.

Conclusions:

• Silicone gel components of mammary implants can alter natural killer (NK) cell activity in animal models.
• The observed level of NK cell suppression in mice is insufficient to compromise host resistance to melanoma.
• Implanted animals exhibit diminished NK cell augmentation responses, suggesting potential immunomodulatory effects.