Fig. 1: PSGL-1 stabilizes cellular F-actin to restrict HIV infection.
From: PSGL-1 inhibits HIV-1 infection by restricting actin dynamics and sequestering HIV envelope proteins
a Immunofluorescence staining of PSGL-1 in HeLa-based MAGI cells overexpressing PSGL-1 using anti-PSGL-1 antibody. Upper panel: PSGL-1 (red) colocalizes with LifeAct-GFP (green), which binds F-actin; Lower panel: PSGL-1 (red) colocalizes with phalloidin (green). Scale bar: 10 μm. b, c Immunofluorescence staining of PSGL-1 using anti-PSGL-1 antibody (green) and phalloidin (red) in Jurkat T cells overexpressing luciferase or PSGL-1. Scale bar: 5 μm. The phalloidin intensity of cells in each group is shown in c. d Jurkat T cells overexpressing luciferase, PSGL-1 or PSGL-1 CD (cytoplasmic domain) alone were stained with phalloidin and analyzed with FACS. Relative MFIs were normalized to luciferase group. MFI mean fluorescence intensity. n = 3. e, f Activated primary CD4+ T cells were treated with IFN-γ or mock-treated for 12 h before being electroporated with two different siRNAs targeting PSGL-1 or non-targeting control siRNA (siNT) for 48 h. The cells were then either fixed for phalloidin staining and FACS quantification (f) or infected with HIV-1 NL4-3 for 72 h before the supernatant being collected for p24 ELISA (e). n = 3 for e, f. g Correlation between cellular F-actin intensities and HIV-1 infection rates in e, f. h, i Activated primary CD4+ T cells from two healthy donors were incubated with PSGL-1 antibody or IgG for 2 h before being fixed for phalloidin staining (h) or infected with HIV-1 NL4-3 for 72 h before the supernatant being collected for p24 measurement (i). n = 3.
