“TCR transgenic, gp100 reactive T cells to target lymphangioleiomyomatosis”

Abstract

Abstract Lymphangioleiomyomatosis (LAM) is a rare lung disease presenting with benign tumors, affecting premenopausal women. LAM is diagnosed by HMB45 staining. We questioned whether gp100 expression by lesional cells lends opportunities to treat LAM by adoptive T cell transfer. As LAM tumors are sparsely infiltrated by T cells, we looked to melanoma and vitiligo as sources of gp100-reactive TCRs. The gp100-reactive TCRs T4H2, R6C12 and SILv44 were cloned into retro-and lentiviral vectors and introduced into primary human CD8+ T cells. Transgenic T cells were combined with melanoma cells, melanocytes and LAM cells and responses were measured by ELISA detecting IFN-γ, IL-17, TNF or IL-4 after 48 hrs. Cytotoxicity was measured by 51Cr release and CD107a expression, and in vivo using SCID/Beige mice challenged with 106 888A2 human melanoma cells and treated twice with 106 SILv44 transduced T cells. Transgenic T cells conferred specific reactivity to HLA-A2+, gp100+ cells, including human LAM10224 cells, in vitro. The SILv44 TCR mediated most IL-17a expression whereas INF-γ secretion was greatest in T4H2 transduced cells. Surprisingly, IL17a expression decreased with increasing peptide concentrations. IL17a+, SILv44+ T cells conferred most anti-tumor protection in mice. LAM10224 cells can form tumors in immunodeficient mice, and SILv44 transgenic T cells should likewise contain such tumors. Thus, SILv44 transgenic T cells may serve as a viable treatment for LAM.