Prevalence of CD4⁺ and FOXP3⁺ cells in MS lesions.

<p>Brain biopsies of 16 MS patients were analyzed by immunohistochemistry for the presence of CD4⁺ and FOXP3⁺ cells. Sections of each biopsy were stained with CD4 mAb, FOXP3 mAb or isotype control mAbs. Whole-slide analysis by complete scanning of the section and computer-aided analysis of positive cells was performed. (<b>A</b>) Representative CD4 immunohistochemistry of MS lesion. Positive cells show red cell surface staining. Bar indicates µm scale in two different magnifications. Tissue was hematoxylin counterstained prior to analysis. (<b>B</b>) Representative FOXP3 immunohistochemistry of MS lesion. Positive cells show brown nuclear staining. Bar indicates µm scale in two different magnifications. Tissue was hematoxylin counterstained prior to analysis. (<b>C</b>) Number of patients with CD4⁺ T cells in the section (0% negative, 100% positive) and number of patients with FOXP3⁺ cells in the analyzed section (31% negative with 69% positive for FOXP3). (<b>D</b>) Number of patients grouped by their content of FOXP3⁺ cells and CD4⁺ cells respectively in the analyzed section: “-“ indicates 0 cells/mm², “(+)” 0-3 cells/mm², “+” >4-15 cells/mm², “++” >15 cells/mm². (<b>E</b>) Number of patients with (+) or without detection of FOXP3⁺ cells (-) in active or inactive MS lesions.