The differential avidity hypothesis (or simply avidity hypothesis) is one of two models that attempt to explain how humans have immunity despite such aggressive selection (positive and negative) to kill developing T cells during their maturation process in the thymus. The other model is the Differential Signaling Hypothesis.
The avidity hypothesis states that the affinity of the T-cell receptor for the MHC:peptide complex and the density of the complex provide different signal strengths upon binding, which in turn dictates the outcome. A strong signal leads to negative selection and thus apoptosis. A weak signal leads to positive selection and thus prevents apoptosis.
Famous quotes containing the words differential, avidity and/or hypothesis:
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—Antonin Artaud (1896–1948)
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