Fig 2. The average SDF1α immunoreactivity of healthy plasma with the RnD SDF1α duoset when immediately analyzed (no incubation, n = 13, range [749–1776 pg/ml]) or after an incubation of 1 h at 37°C (n = 7, range [832–1776 pg/ml]).

Blood was collected in tubes with or without DPP4-I. A significantly lower immunoreactivity was found in regular tubes versus the DPP4-I containing tubes (no incubation: 67.6 ± 3.5%; incubation: 27.8 ± 2.8%; *p < 0.05; results ± SEM).