long-term-intravital-immunofluorescence-imaging-tissue-matrix

Long-term Intravital Immunofluorescence Imaging of Tissue Matrix Components with Epifluorescence and Two-photon Microscopy

Besides being a physical scaffold to maintain tissue morphology, the extracellular matrix (ECM) is actively involved in regulating cell and tissue ...

École Polytechnique Fédérale de Lausanne

There is strong evidence that both adoptive T cell transfer and T cell checkpoint blockade can lead to regression of human melanoma. However, little data are available on the effect of these cancer therapies on the tumor-reactive T cell compartment. To address this issue we have profiled therapy-induced T cell reactivity against a panel of 145 melanoma-associated CD8(+) T cell epitopes. Using this approach, we demonstrate that individual tumor-infiltrating lymphocyte cell products from melanoma patients contain unique patterns of reactivity against shared melanoma-associated antigens, and that the combined magnitude of these responses is surprisingly low. Importantly, TIL therapy increases the breadth of the tumor-reactive T cell compartment in vivo, and T cell reactivity observed post-therapy can almost in full be explained by the reactivity observed within the matched cell product. These results establish the value of high-throughput monitoring for the analysis of immuno-active therapeutics and suggest that the clinical efficacy of TIL therapy can be enhanced by the preparation of more defined tumor-reactive T cell products.

TIL therapy broadens the tumor-reactive CD8(+) T cell compartment in melanoma patients.

Antigen presenting cells (APCs) that express a catalytically inactive version of the deubiquitylase YOD1 (YOD1-C160S) present exogenous antigens more efficiently to CD8(+) T cells, both in vitro and in vivo. Compared with controls, immunization of YOD1-C160S mice led to greater expansion of specific CD8(+) T cells and showed improved control of infection with a recombinant -herpes virus, MHV-68, engineered to express SIINFEKL peptide, the ligand for the ovalbumin-specific TCR transgenic OT-I cells. Enhanced expansion of specific CD8(+) T cells was likewise observed on infection of YOD1-C160S mice with a recombinant influenza A virus expressing SIINFEKL. YOD1-C160S APCs retained antigen longer than did control APCs. Enhanced crosspresentation by YOD1-C160S APCs was transporter associated with antigen processing (TAP1)-independent but sensitive to inclusion of inhibitors of acidification and of the proteasome. The activity of deubiquitylating enzymes may thus help control antigenspecific CD8(+) T-cell responses during immunization.

Manuel Fankhauser

Institute of Bioengineering and Swiss Institute of Experimental Cancer Research (ISREC)

École Polytechnique Fédérale de Lausanne

Long-term Intravital Immunofluorescence Imaging of Tissue Matrix Components with Epifluorescence and Two-photon Microscopy

Manuel Fankhauser

.css-o250i3{font-size:18px;font-family:Open Sans,sans-serif;line-height:21.6px;}Institute of Bioengineering and Swiss Institute of Experimental Cancer Research (ISREC)

École Polytechnique Fédérale de Lausanne

Long-term Intravital Immunofluorescence Imaging of Tissue Matrix Components with Epifluorescence and Two-photon Microscopy

Institute of Bioengineering and Swiss Institute of Experimental Cancer Research (ISREC)