[1] Univ Exeter, Coll Med & Hlth, Exeter, Devon, England
[2] Taunton & Somerset NHS FT, Dept Diabet, Taunton, Somerset, England
[3] Univ Birmingham, Immunol & Immunotherapy, Birmingham, W Midlands, England
[4] Univ Hosp Birmingham NHS FT, Dept Diabet, Birmingham, W Midlands, England