CTLA-4 is expressed by infiltrating T lymphocytes in the heart of chronic Chagas disease patients.

<p>Double immunofluorescence staining with CD3 and CTLA-4 antibodies was performed as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0035966#s2" target="_blank">Material and Methods</a>. From total CD3-expressing T cells present in the inflammatory infiltrate (A) a small proportion showed CTLA-4 expression (B). Nuclei staining with DAPI. The arrowheads point the nuclei of CTLA4<sup>+</sup> cells (C). Composite of figures A, B and C showing the double stained cells (arrowheads) and a CD3<sup>+</sup>CTLA-4<sup>−</sup> single stained cell (large arrow)(D). Original Magnification 400×.</p>