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Updated: Mar 26, 2026

Examination of Thymic Positive and Negative Selection by Flow Cytometry
Published on: October 8, 2012
Thoughts on Positive Selection in Thymus
1Conceptual Immunology Group, The Salk Institute, La Jolla, CA, USA.
Abstract:
Any analysis of the mechanism of signalling during positive selection in the thymus is dependent on one's model of the TCR-ligand interaction. To date, thinking about mechanism has been dominated by what might be termed the Standard (or Centric) model, which is based on analogy between the BCR and the TCR. As the present analysis is an independent rationalized view of the TCR-ligand interactions, it permits a more balanced view of positive selection. The goal here was to explore this alternative to the Standard model.
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