How Finsen's light cured lupus vulgaris

Abstract

In 1903, Niels Ryberg Finsen was awarded the Nobel Prize for his invention of light therapy for skin tuberculosis (lupus vulgaris). The mechanism of action has not been shown; thus, we wanted to elucidate the mechanism of Finsen's light therapy. We measured radiation that could be transmitted through his lens systems and absorption of the stain solution filters in the lamps, and related the obtained results to the possible biological effects on Mycobacterium tuberculosis. Judged from transmission characteristics all tested lens systems were glass lenses (absorbing wavelength < 340 nm). The tested filters likewise absorbed wavelengths < 340 nm. The methylene blue solution used to absorb heat, blocked out wavelengths below 340 nm and between 550 and 700 nm. Furthermore, fluorescence of M. tuberculosis indicated the presence of porphyrins and HPLC analysis of sonicated M. marinum showed that coproporphyrin III was present, which highly justified that porphyrins were present in M. tuberculosis. Production of singlet oxygen through radiation of porphyrins with light of e.g. 400 nm seems to be a most plausible explanation why Finsen's therapy worked in spite of the lack of shortwave ultraviolet radiation, which Finsen believed was the most effective radiation for treating skin tuberculosis.

Vitamin D levels in a large Mediterranean cohort: reconsidering normal cut-off values

“…The immunomodulatory and anti-inflammatory properties of VitD are among its earliest and best described non-classical actions. [112][113][114][115][116][117] Indeed, the acute-phase response has been linked to an early and sharp decrease in circulating 25-(OH)D levels, which correlates with inverse changes in CRP and persists even after resolution of the inflammatory reaction. 110,118,119 Practically all studies evaluating the association between 25-(OH)D levels and acute-phase response have reported a concomitant decrease in serum albumin.…”

Photoinactivation of Mycobacteria In Vitro and in a New Murine Model of LocalizedMycobacterium bovisBCG-Induced Granulomatous Infection

“…In 1900, Niels Finsen was awarded the Nobel Prize for his invention of light therapy for skin tuberculosis, and the underlying mechanism for this successful therapy has been proposed to be excitation of endogenous porphyrins in M. tuberculosis (19). We report here a fresh effort to determine whether the application of photodynamic therapy applied to experimentally localized mycobacteria can be developed as a new effective tool alongside chemotherapeutics in the fight against tuberculosis.…”

Photosensitisers – the progression from photodynamic therapy to anti-infective surfaces

“…At the end of the 19 th century, Niels Finsen pioneered the use of UV light to cure lupis vulgaris in tuberculosis sufferers, and in doing so made aware the potential medical uses of light [2]. A recent study, however, has suggested that the effective wavelength possible with his lenses may have been above 340 nm, thus activating endogenous porphyrins in Mycobacterium tuberculosis to effect treatment, rather than UVmediated bactericidal action [50]. Regardless of the mechanism, his invention was of great benefit, and certainly instrumental in the investigations of microbicidal effects of UV light.…”