FIG. 4.

Confocal laser-scanning micrograph of lymphocyte clusters in human coccidioidal granulomata (scale bar as indicated; original magnification, ×40). Tissues were stained for CD4 (red) and CD25 (green). Representative cell clusters are shown. Panels A and B show the same cluster stained for CD4 and CD25, respectively. Panels C and D show another cluster from the same tissue. CD4⁺ CD25⁺ cells are yellow (arrow) and can be found mostly within the cell clusters. Panel D represents an enlarged portion of panel C showing cell surface colocalization (yellow outline) of the CD4 and CD25 antigens.