Unstable Foxp3

Promiscuous Foxp3-cre activity reveals a differential requirement for CD28 in Foxp3+ and Foxp3− T cells

Costimulatory signals by CD28 are critical for thymic regulatory T-cell (Treg) development. To determine the functional relevance of CD28 for peripheral Treg post thymic selection, we crossed the widely used Forkhead box protein 3 (Foxp3)-CreYFP mice to mice bearing a conditional Cd28 allele. Treg-specific CD28 deficiency provoked a severe autoimmune syndrome as a result of a strong disadvantag...

Parametrizing Unstable and Very Unstable Manifolds

Existence and uniqueness theorems for unstable manifolds are well-known. Here we prove certain refinements. Let f : (C, 0) → C be a germ of an analytic diffeomorphism, whose derivative Df(0) has eigenvalues λ1, . . . , λn such that |λ1| ≥ · · · ≥ |λk| > |λk+1| ≥ · · · ≥ |λn|, with |λk| > 1. Then there is a unique k-dimensional invariant submanifold whose tangent space is spanned by the generali...

Regulation of Foxp3

Functional analysis of FOXP3.

Tolerance to self antigens is established in two ways: first in the thymus through the deletion of thymocytes expressing self-reactive T cell receptors; and second, in the periphery through multiple mechanisms involving deletion, anergy, and suppression. Dominant tolerance to self antigens in the periphery is primarily the function of the CD4(+)CD25(+)FOXP3(+) subset of T cells, which have the ...

Re-redefining Foxp3 function

Including more copper in your everyday diet could be good for your heart, according to a study on page 657. Jiang et al. now find that dietary supplementation of copper offsets the effects of stress on an overworked heart by preventing its enlargement. Copper-carrying proteins disarm oxygen radicals and power electron transport. Humans with copper deficiency have increased cholesterol levels, c...