The effect of C3aRA on C3a-induced MMT. a Schematic showing that macrophages treated with complement C3a for 96 h undergo differentiation to a-SMA+ myofibroblasts. In the present study, we investigated the effect of adding both recombinant C3a and a C3aR antagonist (C3aRA). b–d Total RNA was extracted from BMDMs 48 and 96 h after treatment with C3a (10 ng/ml) plus C3aRA (10uM) or vehicle (DMSO). Control group consisted of untreated BMDMs. The expression of α-SMA (b), collagen-1 (c) and fibrolectin (d) mRNA was investigated by qPCR. Mean ± SEM. *p < 0.05, **p < 0.01. Two-way ANOVA, Bonferroni corrected. e Percentage of α-SMA+ cells in BMDM cultures following 96 h of C3a, C3a + DMSO and C3a + C3aRa treatments. n = 3, representative of the two independent experiments. Mean ± SEM. One-way ANOVA with Bonferroni correction, The asterisk is indicated above the group, significance is compared to the control group (untreated BMDMs). Where the asterisk is indicated between two conditions, significance stated is that between the two groups. *p < 0.05, **p < 0.01. Representative images of α-SMA+ cells (red) in different groups are shown in the left panel.