Background: To screen abnormal pathways and complement components in the kidney of lupus nephritis (LN), and determine a local C3 related therapeutic target in LN.
Methods: KEGG and GO enrichment assay were used to analyze the kidney microarray data of LN patients and NZB/W mice. Immunohistochemistry and immunofluorescence assays were used to measure renal expression of complement-related proteins and TGFβ1. Cytokines were measured using RT-qPCR and ELISA.
Results: We screened the local pathogenic pathways shared by LN patients and NZB/W mice in the kidney and selected the complement activation pathway for further study. We found greater expression of C1QA, C1QB, C3,C3AR1 and C5AR1 at the mRNA and protein levels. C3 is a key factor of the disease and the downstream of C1 is inhibited in the kidney. There were significant correlations between the expression of TGFβ1 and C3 in LN. In addition, our analysis of the primary cell-cultures indicated that TGFβ1 promoted the expression of C3 and that a TGFβ1 antagonist decreased the levels of C3 and C3AR in LN. TGFβ1 inhibition significantly inhibited the deposition of complement-related factors in the kidneys of NZB/W mice.
Conclusions: At the onset of LN, there was significant renal up-regulation of C3 and other complement pathway-related factors in the kidneys of human and NZB/W mice. C3 may lead to albuminuria and participate in the pathogenesis of LN. TGFβ1 promotes C3 synthesis, and TGFβ1 inhibition may block the progression of LN by inhibiting the synthesis of C3 and other complement components.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
This is a list of supplementary files associated with this preprint. Click to download.
Additional file 1: Supplementary Table S1. Clinical data of the study subjects
Additional file 2: Supplementary Figure S1. Volcano plot of genes differentially expressed between each group. The top two figures are results of NZB/W mice, the bottom two figures are results of LN patients. Each point represents one gene that is detectable in both groups. The red points represent the significantly up-regulated genes; the green points represent the significantly down-regulated genes.
Additional file 3: Supplementary Figure S2. Enrichment degrees and p-values of up-regulated KEGG pathways in the kidneys of LN patients. The dot size represents the number of genes enriched on the pathway, the color of the dot represents the significance of each differential expression pathway, and the position of the dot represents the enrichment degree of the pathway.
Additional file 4: Supplementary Figure S3. The levels of C1q and C4 in the plasma of SLE patients. (A) The levels of C1Q in the plasma of SLE patients without LN (N = 38) and patients with LN (N = 28). * p < 0.05. (B) The levels of C4 in the plasma of SLE patients without LN (N = 76) and patients with LN (N = 83). (C) Correlation analysis of the protein levels of C1Q and C3 in plasma of SLE patients (N = 64). (D) Correlation analysis of the protein levels of C4 and C3 in plasma of SLE patients (N = 145). (E) Correlation analysis of the protein levels of C1Q in plasma and the levels of 24-h proteinuria of SLE patients (N = 58). (F) Correlation analysis of the protein levels of C4 in plasma and the levels of 24-h proteinuria of SLE patients (N = 139).
Additional file 5: Supplementary Figure S4. Immunohistochemical analysis of C3 in glomeruli (GLO) or renal tubules (TUB) of different types of LN.
Loading...
Posted 26 Mar, 2021
On 16 Mar, 2021
On 16 Mar, 2021
On 16 Mar, 2021
On 16 Mar, 2021
Posted 26 Mar, 2021
On 16 Mar, 2021
On 16 Mar, 2021
On 16 Mar, 2021
On 16 Mar, 2021
Background: To screen abnormal pathways and complement components in the kidney of lupus nephritis (LN), and determine a local C3 related therapeutic target in LN.
Methods: KEGG and GO enrichment assay were used to analyze the kidney microarray data of LN patients and NZB/W mice. Immunohistochemistry and immunofluorescence assays were used to measure renal expression of complement-related proteins and TGFβ1. Cytokines were measured using RT-qPCR and ELISA.
Results: We screened the local pathogenic pathways shared by LN patients and NZB/W mice in the kidney and selected the complement activation pathway for further study. We found greater expression of C1QA, C1QB, C3,C3AR1 and C5AR1 at the mRNA and protein levels. C3 is a key factor of the disease and the downstream of C1 is inhibited in the kidney. There were significant correlations between the expression of TGFβ1 and C3 in LN. In addition, our analysis of the primary cell-cultures indicated that TGFβ1 promoted the expression of C3 and that a TGFβ1 antagonist decreased the levels of C3 and C3AR in LN. TGFβ1 inhibition significantly inhibited the deposition of complement-related factors in the kidneys of NZB/W mice.
Conclusions: At the onset of LN, there was significant renal up-regulation of C3 and other complement pathway-related factors in the kidneys of human and NZB/W mice. C3 may lead to albuminuria and participate in the pathogenesis of LN. TGFβ1 promotes C3 synthesis, and TGFβ1 inhibition may block the progression of LN by inhibiting the synthesis of C3 and other complement components.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Loading...