Figure 4.

Follicle-like structures of SPMS brains exhibit CD3⁺CD4⁺ T cells, which neither express PD-1 nor FOXP3. (A–E) IF staining of CD3, CD4 and PD-1 reveal CD3⁺CD4⁺PD-1⁻ T-helper cells in progressive MS. Inserts in the upper right corners show magnification of the white box. (F–I) IF staining of CD3 and FOXP3 on serial sections of a representative meningeal follicle-like structure in SPMS (same region as Figure 3). CD3⁺ T cells, but no FOXP3⁺ cells were detected. Inserts show magnification of the white box. Scale bars indicate 100 μm, inserts 10 μm.