Short-term changes in frequencies of circulating leukocytes associated with narrowband UVB phototherapy in people with clinically isolated syndrome

Sci Rep. 2019 May 28;9(1):7980. doi: 10.1038/s41598-019-44488-6.


Clinically isolated syndrome (CIS) is the earliest clinical episode in multiple sclerosis (MS). Low environmental exposure to UV radiation is implicated in risk of developing MS, and therefore, narrowband UVB phototherapy might delay progression to MS in people with CIS. Twenty individuals with CIS were recruited, and half were randomised to receive 24 sessions of narrowband UVB phototherapy over a period of 8 weeks. Here, the effects of narrowband UVB phototherapy on the frequencies of circulating immune cells and immunoglobulin levels after phototherapy are reported. Peripheral blood samples for all participants were collected at baseline, and 1, 2, 3, 6 and 12 months after enrolment. An extensive panel of leukocyte populations, including subsets of T cells, B cells, monocytes, dendritic cells, and natural killer cells were examined in phototherapy-treated and control participants, and immunoglobulin levels measured in serum. There were significant short-term increases in the frequency of naïve B cells, intermediate monocytes, and fraction III FoxP3+ T regulatory cells, and decreases in switched memory B cells and classical monocytes in phototherapy-treated individuals. Since B cells are increasingly targeted by MS therapies, the effects of narrowband UVB phototherapy in people with MS should be investigated further.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • B-Lymphocyte Subsets / immunology
  • B-Lymphocyte Subsets / pathology
  • B-Lymphocyte Subsets / radiation effects*
  • Calcifediol / blood
  • Demyelinating Diseases / complications
  • Demyelinating Diseases / immunology
  • Demyelinating Diseases / pathology
  • Demyelinating Diseases / therapy*
  • Dendritic Cells / immunology
  • Dendritic Cells / pathology
  • Dendritic Cells / radiation effects*
  • Disease Progression
  • Female
  • Flow Cytometry
  • Humans
  • Immunoglobulins / blood
  • Immunologic Memory / radiation effects
  • Immunophenotyping
  • Killer Cells, Natural / immunology
  • Killer Cells, Natural / pathology
  • Killer Cells, Natural / radiation effects*
  • Longitudinal Studies
  • Male
  • Middle Aged
  • Monocytes / immunology
  • Monocytes / pathology
  • Monocytes / radiation effects*
  • Multiple Sclerosis / etiology
  • Multiple Sclerosis / immunology
  • Multiple Sclerosis / pathology
  • Multiple Sclerosis / prevention & control
  • T-Lymphocyte Subsets / immunology
  • T-Lymphocyte Subsets / pathology
  • T-Lymphocyte Subsets / radiation effects*
  • Ultraviolet Rays
  • Ultraviolet Therapy / methods


  • Immunoglobulins
  • Calcifediol