Fig. 7

MHC-II expressing astrocytes are situated in close contact with CD4⁺ T cells in the human brain. Double immunostainings of GFAP and CD4 indicated close contact between perivascular CD4⁺ T cells and GFAP⁺ astrocytes in the vessel wall (a). A close-up confocal image of the white rectangle is shown in a’. Triple immunostainings with specific antibodies to GFAP, CD4, and MHC-II verified that there is an interaction between CD4⁺ T cells and MHC-II expressing astrocytes in the blood vessel wall (b). Close-up images of the separate channels are shown in b’. Infiltrated CD4⁺ T cells in the parenchyma were also found to be encapsulated by MHC-II expressing astrocytes (c). The separate channels of the confocal image are shown to the right in c'. The blood vessels in (a) and (b) are indicated with white stars. Scale bars: (a and c) = 2 μm, (b) = 20 μm