Narrowband UVB phototherapy reduces TNF production by B-cell subsets stimulated via TLR7 from individuals with early multiple sclerosis.

Reduced TNF responses after TLR7 stimulation in marginal zone-like B cells from participants administered phototherapy suggested treatment-associated priming effects that were detected upon subsequent polyclonal B-cell activation. Changes in responsiveness to TLR7 stimulation also suggested that IgM-only memory B cells may be important in conversion from CIS to MS.