Quantification of CD4(+) T Cell Alloreactivity and Its Control by Regulatory T Cells Using Time-Lapse Microscopy and Immune Synapse Detection

Autor: S C, Juvet, S, Sanderson, J, Hester, K J, Wood, A, Bushell
Rok vydání: 2015
Předmět:
Zdroj: American Journal of Transplantation
ISSN: 1600-6143
Popis: Assays designed to select transplant recipients for immunosuppression withdrawal have met with limited success, perhaps because they measure events downstream of T cell–alloantigen interactions. Using in vitro time‐lapse microscopy in a mouse transplant model, we investigated whether transplant outcome would result in changes in the proportion of CD4+ T cells forming prolonged interactions with donor dendritic cells. By blocking CD4–MHC class II and CD28–B7 interactions, we defined immunologically relevant interactions as those ≥500 s. Using this threshold, T cell–dendritic cell (T‐DC) interactions were examined in rejection, tolerance and T cell control mediated by regulatory T cells. The frequency of T‐DC contacts ≥500 s increased with T cells from mice during acute rejection and decreased with T cells from mice rendered unresponsive to alloantigen. Regulatory T cells reduced prolonged T‐DC contacts. Importantly, this effect was replicated with human polyclonally expanded naturally occurring regulatory T cells, which we have previously shown can control rejection of human tissues in humanized mouse models. Finally, in a proof‐of‐concept translational context, we were able to visualize differential allogeneic immune synapse formation in polyclonal CD4+ T cells using high‐throughput imaging flow cytometry.
The authors measure mouse and human CD4+ T cell alloreactivity using time‐lapse microscopy and imaging flow cytometry techniques, and demonstrate that these measurements predict graft outcome in tolerized and rejecting animals. See the supporting video at amjtransplant.com/videos.
Databáze: OpenAIRE
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