An action spectrum for ultraviolet radiation-induced immunosuppression in humans

Abstract

Longwave UVA, which abuts the visible light spectrum and is less effectively filtered by sunscreens than UVB, is likely to be the largest contributor to immunosuppression resulting from incidental daily sun exposure.

Are current guidelines for sun protection optimal for health? Exploring the evidence

“…Second, UVA irradiation has been shown to cause local immune sup-pression in human studies, with peak effectiveness at 370 nm and with a bell-shaped dose response. 18 We note that this is contrary to older evidence from animal studies that exposure to UVA counteracts the effects of UVB-induced immune suppression. 32 Whether this reflects the complexity of the effects of UV radiation on immune suppression or a disparity in findings between human and animal studies, is not clear.…”

“…17 Both UVA and UVB irradiation cause immune suppression, acting through a range of different chromophores with specific absorption spectra. 18,19 Recent research suggests that UV-induced immune suppression could have both benefits (e.g., suppressing autoimmunity 20 ) and adverse effects (e.g., suppressing immune responses to vaccination 21 ) for human health. Although UVB photons are more effectively immunosuppressant, UV-induced immune suppression may be mainly UVA-induced since there is a peak of immune suppression in the UVA waveband and UVA is much more abundant at Earth's surface than UVB (see Table 1 and Fig.…”

The Efficacy of Afamelanotide and Narrowband UV-B Phototherapy for Repigmentation of Vitiligo

“…2,14 Moreover, NB-UV-B may induce immunosuppression. 26 The potential therapeutic efficacy may be further enhanced by the ability of afamelanotide to scavenge reactive oxygen species. 27 Further studies are indeed necessary to elucidate whether afamelanotide combined with NB-UV-B or as monotherapy can be used to potentially reverse pathogenic mechanisms in patients with vitiligo.…”

18-årsgrensen for solariebruk skal håndheves

“…The effects are dose dependent. The immunosuppressive effect of (narrow-band) UVA was apparent at doses in the range 300 to 1000 mJ/cm 2 ; this effect of UVA disappeared at higher doses (Matthews et al, 2010, Damian et al, 2011. Studies in mice showed for UVA a photoimmune protective effect on immunosuppression (Reeve et al, 2009).…”