Project description:Mature neutrophis were freshly isolated from blood of pediatric systemic lupus erythematosus (SLE) patients and healthy donors. Illumina microarray was used to assess transcriptional changes between SLE group and Control group. To uderstand further the gene expression difference between SLE and healthy neutrofils, neutrophils from healthy donors were cultured with autologous sera, SLE sera or Interferon and microarray data was used to compare with fresh SLE neutrophils. (Expt 1) Neutrophils from 21 SLE samples (19 patients) and 12 healthy donors were isolated, and extracted RNAs were used generate microarray data. (Expt 2) Neutrophils isolated from 2 healthy children (not used in the first experiment) were cultured with autologous sera (control), Interferon alpha (100U and 1000U), and 4 SLE sera and 6 SLE sera for 6 hours and RNAs were extract for microarray experiment.
Project description:Mature neutrophis were freshly isolated from blood of pediatric systemic lupus erythematosus (SLE) patients and healthy donors. Illumina microarray was used to assess transcriptional changes between SLE group and Control group. To uderstand further the gene expression difference between SLE and healthy neutrofils, neutrophils from healthy donors were cultured with autologous sera, SLE sera or Interferon and microarray data was used to compare with fresh SLE neutrophils.
Project description:Autoantibodies against nucleic acids and excessive type I Interferon (IFN) are hallmarks of human Systemic Lupus Erythematosus (SLE). We previously reported that SLE neutrophils, exposed to TLR7-agonist autoantibodies, release interferogenic DNA, which we now demonstrate to be of mitochondrial origin. We further show that healthy human neutrophils do not complete mitophagy upon induction of mitochondrial damage. Rather, they extrude mitochondrial components, including DNA (mtDNA), devoid of oxidized residues. When MtDNA undergoes oxidation, it is directly routed to lysosomes for degradation. This rerouting requires dissociation from the transcription factor TFAM, a dual high mobility group (HMG) protein involved in maintenance and compaction of the mitochondrial genome into nucleoids. Exposure of SLE neutrophils, or healthy IFNprimed neutrophils, to anti-RNP autoantibodies blocks TFAM phosphorylation, a necessary step for nucleoid dissociation. Consequently, oxidized nucleoids accumulate within mitochondria and are eventually extruded as potent interferogenic complexes. In support of the in vivo relevance of this phenomenon, mitochondrial retention of oxidized nucleoids is a feature of SLE blood neutrophils, and autoantibodies against oxidized mtDNA are present in a fraction of patients. This pathway represents a novel therapeutic target in human SLE. 4 samples, no replicates, 2 controls. 2 samples are Neutrophils cultured with and without CCCP (control). 2 samples are Monocytes cultured with and without CCCP (control).
Project description:Monocytes from 3 healthy donors were cultured for 6 hours in the presence of 20% serum from three newly diagnosed, untreated SLE patients. Microarray analysis was then performed upon normalizing the gene expression levels of samples incubated with SLE sera to those incubated with autologous serum. Monocytes from 3 healthy donors were cultured for 6 hours in the presence of 20% serum from three newly diagnosed, untreated SLE patients. Microarray analysis was then performed upon normalizing the gene expression levels of samples incubated with SLE sera to those incubated with autologous serum.
Project description:Monocytes from 3 healthy donors were cultured for 6 hours in the presence of 20% serum from three newly diagnosed, untreated SLE patients. Microarray analysis was then performed upon normalizing the gene expression levels of samples incubated with SLE sera to those incubated with autologous serum.
Project description:The aim of the study was to test the hypothesis that SLE patient sera contains IgG reactivity to serum factor antigens concomitant with prototypical autoimmne antigens. We diluted patient sera 1:250 and incubated dilutions on a nitrocellulose-platform array printed with whole protein antigens. In this study, serum from 45 individuals (subsetted into high and low interferon signature as well as healthy control categories) was profiled for IgG autoantibody reactivity to whole protein autoimmune and serum factor antigens. SLE and specifically IFN high patient sera was found using the significance analysis of microarrays (SAM) algorithm to be significantly more reactive with prototypical autoimmune antigens and select serum factor array antigens.
Project description:Stimulation experiments were done with PBMC from SLE or healthy donors treated with CSL362 or isotype control before stimulation with various stimuli including the TLR9 agonist 0.25 μM CpGc; the TLR4 agonist 10 μg/ml LPS; and the TLR3 agonist 10 μg/ml POLY I:C. As well as the SLE specific stimuli SLE immunoglobulin (Ig) + necrotic cell lysates (NCL) to form immune complexes; control healthy donor Ig + NCL; and SLE sera + NCL; or healthy donor sera + NCL to understand the specific effects of pDC depletion on different inducible gene transcripts.
Project description:This study used proteomic, biomechanical, and functional analyses to further define neutrophil heterogeneity in the context of SLE. Mass spectrometry proteomic and phosphoproteomic analyses were performed in healthy control normal density neutrophils (NDNs), SLE NDNs and in autologous SLE LDGs. Proteomic and phosphoproteomic differences were detected when comparing control to SLE neutrophils and when comparing SLE NDNs to SLE LDGs.
Project description:Autoantibodies against nucleic acids and excessive type I Interferon (IFN) are hallmarks of human Systemic Lupus Erythematosus (SLE). We previously reported that SLE neutrophils, exposed to TLR7-agonist autoantibodies, release interferogenic DNA, which we now demonstrate to be of mitochondrial origin. We further show that healthy human neutrophils do not complete mitophagy upon induction of mitochondrial damage. Rather, they extrude mitochondrial components, including DNA (mtDNA), devoid of oxidized residues. When MtDNA undergoes oxidation, it is directly routed to lysosomes for degradation. This rerouting requires dissociation from the transcription factor TFAM, a dual high mobility group (HMG) protein involved in maintenance and compaction of the mitochondrial genome into nucleoids. Exposure of SLE neutrophils, or healthy IFNprimed neutrophils, to anti-RNP autoantibodies blocks TFAM phosphorylation, a necessary step for nucleoid dissociation. Consequently, oxidized nucleoids accumulate within mitochondria and are eventually extruded as potent interferogenic complexes. In support of the in vivo relevance of this phenomenon, mitochondrial retention of oxidized nucleoids is a feature of SLE blood neutrophils, and autoantibodies against oxidized mtDNA are present in a fraction of patients. This pathway represents a novel therapeutic target in human SLE.
Project description:To better characterize the molecules that could potentially confer antigen presenting capacity to SLE monocytes, we assessed their gene expression profile. Blood monocytes from five healthy controls and five pediatric SLE patients were isolated using CD14+ selection. Because drugs used to treat SLE could induce considerable transcriptional changes, we selected active, newly diagnosed patients who had never received oral or intravenous (IV) medications.