Article

Reaggregate thymus cultures.

MRC Center for Immune Regulation, University of Birmingham.
Journal of Visualized Experiments (Impact Factor: 1.33). 02/2008; DOI: 10.3791/905
Source: PubMed

ABSTRACT Stromal cells within lymphoid tissues are organized into three-dimensional structures that provide a scaffold that is thought to control the migration and development of haemopoeitic cells. Importantly, the maintenance of this three-dimensional organization appears to be critical for normal stromal cell function, with two-dimensional monolayer cultures often being shown to be capable of supporting only individual fragments of lymphoid tissue function. In the thymus, complex networks of cortical and medullary epithelial cells act as a framework that controls the recruitment, proliferation, differentiation and survival of lymphoid progenitors as they undergo the multi-stage process of intrathymic T-cell development. Understanding the functional role of individual stromal compartments in the thymus is essential in determining how the thymus imposes self/non-self discrimination. Here we describe a technique in which we exploit the plasticity of fetal tissues to re-associate into intact three-dimensional structures in vitro, following their enzymatic disaggregation. The dissociation of fetal thymus lobes into heterogeneous cellular mixtures, followed by their separation into individual cellular components, is then combined with the in vitro re-association of these desired cell types into three-dimensional reaggregate structures at defined ratios, thereby providing an opportunity to investigate particular aspects of T-cell development under defined cellular conditions [corrected].

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Available from: Graham Anderson, Sep 02, 2014
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    • "Attempts to engineer an artificial thymus have mostly used traditional tissue engineering approaches involving chemical scaffolds and cells liberated from isolated tissues, although newer methods involving decellularised organs show some potential. More simplistic methods to 'engineer' a thymus are foetal thymus organ culture (FTOC) and reaggregate thymus organ culture (RTOC) (Figure 2) (Anderson and Jenkinson 2007; White et al. 2008). These are both methods whereby the foetal thymus is ablated of T cell precursors prior to addition of HSC derived cells. "
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