Analysis of the adult thymus in reconstitution of T lymphocytes in HIV-1 infection

Abstract

Immunohistological analysis of the thymus in HIV infection. (a-d) Thymus from HIV-1+ patient no. 1 with no thymopoiesis. (e-h) Thymus from HIV-1 + patient no. 2 with areas of active thymopoiesis. (a) Hematoxylin and eosin stain of patient no. 1's lymphoid thymus. 13. (b) A similar area as in a, with thymic epithelium in immunohistological analysis reactive with antikeratin antibody (brown central areas). All keratin + thymic epithelium (e) in the true thymus is collapsed (dark brown areas) and devoid of lymphocytes, with a surrounding infiltrate of blue mononuclear cells present in the thymic perivascular space (P). 13. (c) Immunohistological stain of CD8 + T cells (brown cells; see arrows for examples) in the perivascular space (P) around a central empty thymic epithelial island (e). The dotted line surrounds thymic true epithelial thymus areas (e), and the short arrow points out a rare CD8 + T cell within the true epithelial thymus (e). 66. (d) Many of the perivascular space (P) CD8 + cells are reactive with MAB TIA-1 (arrows) and therefore are mature effector cytotoxic T cells. 66. e-h are from patient no. 2's thymus. 33. (e) Light microscopic view of patient no. 2's thymus (hematoxylin and eosin stain with a Hassall's body [h] in the thymus medulla). (f) Immunohistological analysis with antikeratin antibody, with areas of normal-appearing keratin + thymic epithelium (brown areas) filled with lymphocytes (blue areas) intermingled with thymic epithelium (arrows). Most developing thymocytes are CD3 + T cells (arrows in g), many of which are normal CD1a + cortical thymocytes (brown cells, arrows in h). A subset of these CD1a + , CD3 + immature thymocytes were actively dividing as determined by nuclear reactivity with MAB mib-1 (not shown). MAB, monoclonal antibody.