Related to Figs. 4 and 5. (A–C) Related to Fig. 4. (A) Analysis of Myosin expression and MLC phosphorylation by Western blot: MDMs were transfected with non-targeting siRNA (siCTRL) or targeting Myosin IIA (siMYO). Left: Representative images of Western blot analysis of the expression of Myosin IIA (top) and p-MLC (middle), with actin as loading control (bottom). Right: Quantification of Myosin IIA/actin, normalized to the siRNA control condition (n = 6 donors, median ± interquartile range). (B) Quantification of p-MLC/actin, normalized to the siCTRL condition (n = 6 donors, median ± interquartile range). (C) Representative images of actomyosin cytoskeleton of MDMs treated with siCTL or siMYO. F-actin (phalloidin, gray), Myosin IIA (red), and nuclei (DAPI, cyan). Scale bars, 10 µm. (D–G) Related to Fig. 5. (D) Quantification by flow cytometry of infection of MDMs incubated with isotype control (Control) or antibody targeting CD9 (anti-CD9) and co-cultured with infected Jurkat cells, normalized to the isotype control condition (n = 10 donors, median ± interquartile range). (E) Analysis of CD81 depletion by flow cytometry: MDMs were transfected with non-targeting siRNA (siCTRL) or targeting CD81 (siCD81). Left: Representative dot plot of CD81 signals. Right: Quantification of CD81 expression, normalized to the siCTRL condition (n = 6 donors, mean ± SD). (F) Flow cytometry analysis of alveolar macrophages infection after a 24 h-co-culture with uninfected Jurkat cells (NI) or Jurkat cells infected for 2 d in presence of anti-CD81 antibody or corresponding isotype control. Representative dot plots of HIV-p24 signals and gating strategy for selection of infected cells. See quantification in Fig. 5 D. (G) Representative images of actomyosin cytoskeleton of MDMs treated with siCTL or siCD81. F-actin (phalloidin, gray), Myosin IIA (red), and nuclei (DAPI, cyan). (G) This image comes from a mosaic (stitched together by the microscope). Scale bars, 10 µm. Statistical analyses: (A, B, and D) Wilcoxon test and (E) Paired t test. * P ≤ 0.05. Source data are available for this figure: SourceData FS7.