Limits...
Local synthesis of interferon-alpha in lupus nephritis is associated with type I interferons signature and LMP7 induction in renal tubular epithelial cells.

Castellano G, Cafiero C, Divella C, Sallustio F, Gigante M, Pontrelli P, De Palma G, Rossini M, Grandaliano G, Gesualdo L - Arthritis Res. Ther. (2015)

Bottom Line: Type I interferons signature was characterized by MXA-specific staining in renal tubular epithelial cells; in addition, in situ hybridization showed that renal tubular epithelial cells were the major producers of interferon-alpha, indicating a potential autocrine effect.Whole-genome expression profile showed interferon-alpha induced up-regulation of genes involved in innate immunity, protein ubiquitination and switching to immunoproteasome.Our data indicate that type I interferons might have a pathogenic role in lupus nephritis characterized by an autocrine effect of interferon-alpha on renal tubular epithelial cells.

View Article: PubMed Central - PubMed

Affiliation: Renal, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari, Piazza Giulio Cesare 11, 70124, Bari, Italy. giuseppe.castellano@uniba.it.

ABSTRACT

Introduction: Type I interferons are pivotal in the activation of autoimmune response in systemic lupus erythematous. However, the pathogenic role of interferon-alpha in patients affected by lupus nephritis remains uncertain. The aim of our study was to investigate the presence of a specific interferon signature in lupus nephritis and the effects of interferon-alpha at renal level.

Methods: We performed immunohistochemical analysis for MXA-protein and in situ hybridization to detect interferon-alpha signature and production in human lupus nephritis. Through microarray studies, we analyzed the gene expression profile of renal tubular epithelial cells, stimulated with interferon-alpha. We validated microarray results through real-time polymerase chain reaction, flow cytometry on renal tubular epithelial cells, and through immunohistochemical analysis and confocal microscopy on renal biopsies.

Results: Type I interferons signature was characterized by MXA-specific staining in renal tubular epithelial cells; in addition, in situ hybridization showed that renal tubular epithelial cells were the major producers of interferon-alpha, indicating a potential autocrine effect. Whole-genome expression profile showed interferon-alpha induced up-regulation of genes involved in innate immunity, protein ubiquitination and switching to immunoproteasome. In accordance with the in vitro data, class IV lupus nephritis showed up-regulation of the immunoproteasome subunit LMP7 in tubular epithelial cells associated with type I interferon signature.

Conclusions: Our data indicate that type I interferons might have a pathogenic role in lupus nephritis characterized by an autocrine effect of interferon-alpha on renal tubular epithelial cells. Therefore we hypothesize that inhibition of type I interferons might represent a therapeutic target to prevent tubulo-interstitial damage in patients with lupus nephritis.

Show MeSH

Related in: MedlinePlus

Detection of IFN-alpha signature in renal biopsies of patients affected by lupus nephritis. (A-C) Infiltrating plasmacytoid DC in class IV lupus nephritis were characterized with a double staining for MXA (green, A) and BDCA-2 (red, B), a specific plasmacytoid DC marker (C, merge analysis). (D) Type I IFN-induced MXA protein was rarely detectable in class I lupus nephritis; (E) on the contrary, MXA positive tubular epithelial cells and infiltrating leucocytes were detectable in class IV lupus nephritis. (F) PAS staining on a seriate tissue section of the same specimen stained for MXA. (G) Immunohistochemistry analysis for MXA was performed on renal biopsies of eight patients for each group, as described in the Methods section. DC, dendritic cells; PAS, Periodic acid-Schiff.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4389585&req=5

Fig1: Detection of IFN-alpha signature in renal biopsies of patients affected by lupus nephritis. (A-C) Infiltrating plasmacytoid DC in class IV lupus nephritis were characterized with a double staining for MXA (green, A) and BDCA-2 (red, B), a specific plasmacytoid DC marker (C, merge analysis). (D) Type I IFN-induced MXA protein was rarely detectable in class I lupus nephritis; (E) on the contrary, MXA positive tubular epithelial cells and infiltrating leucocytes were detectable in class IV lupus nephritis. (F) PAS staining on a seriate tissue section of the same specimen stained for MXA. (G) Immunohistochemistry analysis for MXA was performed on renal biopsies of eight patients for each group, as described in the Methods section. DC, dendritic cells; PAS, Periodic acid-Schiff.

Mentions: IFN-alpha has a pivotal role in the pathogenesis of autoimmune response in SLE. Therefore, we analyzed renal biopsies from SLE patients affected by lupus nephritis to detect signs of IFN-alpha signaling at the renal level. We used an antibody directed against MXA, a specific protein induced by this type of IFN [17]. As expected (Figure 1A-C), we found that plasmacytoid DC, the major producer of IFN-alpha, stained positive for MXA [17], especially in class IV lupus nephritis, as shown by co-localization of MXA with BDCA2 (Figure 1A-C), a marker of plasmacytoid DCs.Figure 1


Local synthesis of interferon-alpha in lupus nephritis is associated with type I interferons signature and LMP7 induction in renal tubular epithelial cells.

Castellano G, Cafiero C, Divella C, Sallustio F, Gigante M, Pontrelli P, De Palma G, Rossini M, Grandaliano G, Gesualdo L - Arthritis Res. Ther. (2015)

Detection of IFN-alpha signature in renal biopsies of patients affected by lupus nephritis. (A-C) Infiltrating plasmacytoid DC in class IV lupus nephritis were characterized with a double staining for MXA (green, A) and BDCA-2 (red, B), a specific plasmacytoid DC marker (C, merge analysis). (D) Type I IFN-induced MXA protein was rarely detectable in class I lupus nephritis; (E) on the contrary, MXA positive tubular epithelial cells and infiltrating leucocytes were detectable in class IV lupus nephritis. (F) PAS staining on a seriate tissue section of the same specimen stained for MXA. (G) Immunohistochemistry analysis for MXA was performed on renal biopsies of eight patients for each group, as described in the Methods section. DC, dendritic cells; PAS, Periodic acid-Schiff.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4389585&req=5

Fig1: Detection of IFN-alpha signature in renal biopsies of patients affected by lupus nephritis. (A-C) Infiltrating plasmacytoid DC in class IV lupus nephritis were characterized with a double staining for MXA (green, A) and BDCA-2 (red, B), a specific plasmacytoid DC marker (C, merge analysis). (D) Type I IFN-induced MXA protein was rarely detectable in class I lupus nephritis; (E) on the contrary, MXA positive tubular epithelial cells and infiltrating leucocytes were detectable in class IV lupus nephritis. (F) PAS staining on a seriate tissue section of the same specimen stained for MXA. (G) Immunohistochemistry analysis for MXA was performed on renal biopsies of eight patients for each group, as described in the Methods section. DC, dendritic cells; PAS, Periodic acid-Schiff.
Mentions: IFN-alpha has a pivotal role in the pathogenesis of autoimmune response in SLE. Therefore, we analyzed renal biopsies from SLE patients affected by lupus nephritis to detect signs of IFN-alpha signaling at the renal level. We used an antibody directed against MXA, a specific protein induced by this type of IFN [17]. As expected (Figure 1A-C), we found that plasmacytoid DC, the major producer of IFN-alpha, stained positive for MXA [17], especially in class IV lupus nephritis, as shown by co-localization of MXA with BDCA2 (Figure 1A-C), a marker of plasmacytoid DCs.Figure 1

Bottom Line: Type I interferons signature was characterized by MXA-specific staining in renal tubular epithelial cells; in addition, in situ hybridization showed that renal tubular epithelial cells were the major producers of interferon-alpha, indicating a potential autocrine effect.Whole-genome expression profile showed interferon-alpha induced up-regulation of genes involved in innate immunity, protein ubiquitination and switching to immunoproteasome.Our data indicate that type I interferons might have a pathogenic role in lupus nephritis characterized by an autocrine effect of interferon-alpha on renal tubular epithelial cells.

View Article: PubMed Central - PubMed

Affiliation: Renal, Dialysis and Transplantation Unit, Department of Emergency and Organ Transplantation, University of Bari, Piazza Giulio Cesare 11, 70124, Bari, Italy. giuseppe.castellano@uniba.it.

ABSTRACT

Introduction: Type I interferons are pivotal in the activation of autoimmune response in systemic lupus erythematous. However, the pathogenic role of interferon-alpha in patients affected by lupus nephritis remains uncertain. The aim of our study was to investigate the presence of a specific interferon signature in lupus nephritis and the effects of interferon-alpha at renal level.

Methods: We performed immunohistochemical analysis for MXA-protein and in situ hybridization to detect interferon-alpha signature and production in human lupus nephritis. Through microarray studies, we analyzed the gene expression profile of renal tubular epithelial cells, stimulated with interferon-alpha. We validated microarray results through real-time polymerase chain reaction, flow cytometry on renal tubular epithelial cells, and through immunohistochemical analysis and confocal microscopy on renal biopsies.

Results: Type I interferons signature was characterized by MXA-specific staining in renal tubular epithelial cells; in addition, in situ hybridization showed that renal tubular epithelial cells were the major producers of interferon-alpha, indicating a potential autocrine effect. Whole-genome expression profile showed interferon-alpha induced up-regulation of genes involved in innate immunity, protein ubiquitination and switching to immunoproteasome. In accordance with the in vitro data, class IV lupus nephritis showed up-regulation of the immunoproteasome subunit LMP7 in tubular epithelial cells associated with type I interferon signature.

Conclusions: Our data indicate that type I interferons might have a pathogenic role in lupus nephritis characterized by an autocrine effect of interferon-alpha on renal tubular epithelial cells. Therefore we hypothesize that inhibition of type I interferons might represent a therapeutic target to prevent tubulo-interstitial damage in patients with lupus nephritis.

Show MeSH
Related in: MedlinePlus