PHENOTYPE OF LYMPHOCYTES ASSOCIATED WITH THE INFLAMMATORY REACTION TOSILICONE GEL BREAST IMPLANTS

The tissue response to silicone gel breast implants typically includes an inflammatory infiltrate that consists of macrophages, foreign body -type giant cells, and a variable number of lymphocytes acid plasma ce lls. The phenotype of the lymphocytic component was investigated with three-color flow cytometry. Lymphocytes were obtained by collecting fl uid from the space between the implant and the fibrous capsule or by w ashing cells from the fibrous capsule at the time of implant removal w ith total capsulectomy. Eighty-nine percent of the implant-associated lymphocytes were T cells. Twenty-five percent of the CD3(+) T cells co expressed HLA-DR compared with only 7.9% of matched peripheral blood l ymphocytes. Sixty-eight percent of the implant-associated T cells coex pressed CD3 and CD29, while only 3% of the T cells coexpressed CD4 and CD45RO. The expression of HLA-DR and the predominance of CD29(+) CD4( +) T cells indicate that there is immune activation with the potential for stimulating antigen-specific antibody production. The role of sil icone gel breast implants in immune activation and its clinical signif icance require further investigation.