| Popis: |
A major hub of adaptive immunity is the lymph node, which has a highly organized and dynamic structure. Most techniques currently used to study the lymph node ex vivo begin by reducing the tissue to a cell suspension, thus losing the spatial organization, or fixing the tissue, thus losing the ability to make measurements over time or after stimulation. Live tissue slices offer the potential to retain spatial complexity and provide the dynamic accessibility of traditional in vitro measurements, but this approach has not been rigorously validated for murine lymph node tissue. Here we describe a systematic characterization of live murine lymph node slices as a platform to study immunity. Live lymph node slices maintained the expected spatial organization and were comprised of the expected cell populations. Slices collected under optimized conditions were comparable to cell suspensions both in terms of 24-hr viability and inflammation. Slices processed protein antigens and responded to T cell receptor cross-linking with expected surface marker expression and cytokine secretion. Interestingly, IFN-γ but not IL-2 secretion from slices was higher than from cell suspensions after both CD3 and R848 stimulation. Furthermore, slices from vaccinated animals responded to ex vivo antigen challenge with antigen-specific cytokine secretion. In summary, lymph node slices provide an experimental platform that maintains spatial organization and temporal dynamics, while allowing for controlled stimulus-response experiments with multiple parallel read-outs. We anticipate that tissue slices may serve as a versatile tool to investigate immune functions within the lymph node. |
