Fig. 5: CGRP decreases 3-OS HS expression and abrogates pH dependency during HSV-1 infection of human LCs.

a, b Untreated or CGRP-treated MDLCs were pre-incubated for 1 h at 37 °C with nAbs to nectin-1, HVEM, PILR-α or langerin vs. matched isotype non-neutralizing control Abs, or pre-incubated with heparinase II/III vs. medium. Cells were then pulsed for 2 h with HSV-1 (isolate 3 at MOI = 1.0) and infection was examined 24 h pi by flow cytometry. Results represent mean ± SEM percentages of HSV-1 infection inhibition (a, n = 7) or normalized against untreated cells (b, n = 5). c Representative flow cytometry overlay, showing surface expression of 3-OS HS in untreated (empty histogram) and CGRP-treated (filled grey histogram) MDLCs vs. isotype control (broken line). Numbers represent mean ± SEM (n = 3) MFIs of 3-OS HS expression, gated on langerin⁺ MDLCs. d Untreated or CGRP-treated inner foreskin epidermal cell suspensions were pre-incubated for 1 h at 37 °C with heparinase II + III or langerin nAb. Cells were then pulsed for 24 h with HSV-1 (isolate 3 at MOI = 10.0), and infection was examined 48 h pi by flow cytometry. Results represent mean ± SEM (using n = 3 tissues from different individuals) percentages of HSV-1 infection normalized against untreated cells. e, f Untreated or CGRP-treated MDLCs were pulsed with HSV-1 (isolates 1 at MOI = 0.1 and isolate 2 at MOI = 0.2), alone or in the presence of NH₄Cl or bafilomycin A1 during the 2 h pulse period (e) or 24 h CGRP treatment period (f), and infection was measured 24 h pi by flow cytometry. Results represent mean ± SEM (n = 3–5) percentages of HSV-1 infection normalized against untreated cells. In all graphs, *p < 0.0500, **p < 0.0050 and ***p < 0.0005; two-tailed Student’s t-test.