Plasma concentrations of interleukin (IL)-35 and soluble IL-35R component gp130 and IL-12Rβ2 in Murphy Roths Large (MRL)/lpr and BALB/c mice with IL-35 or phosphate-buffered saline (PBS) treatment. Results of the concentrations of plasma (a) IL-35, (b) gp130 and (c) IL-12Rβ2 are presented as bar charts with the arithmetic mean plus standard error of the mean (s.e.m.). *P < 0·05, **P < 0·01, ***P < 0·001, PBS versus IL-35 treatment; †††P < 0·001, BALB/c control mice versus PBS-treated MRL/lpr mice; ‡‡‡P < 0·001, BALB/c control mice versus IL-35-treated MRL/lpr mice (n = 5 in each group).