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Use of combined hormonal contraceptives among women with systemic lupus erythematosus with and without medical contraindications to oestrogen
Mendel, Arielle; Bernatsky, Sasha; Pineau, Christian A; St-Pierre, Yvan; Hanly, John G; Urowitz, Murray B; Clarke, Ann E; Romero-Diaz, Juanita; Gordon, Caroline; Bae, Sang-Cheol; Wallace, Daniel J; Merrill, Joan T; Buyon, Jill; Isenberg, David A; Rahman, Anisur; Ginzler, Ellen M; Petri, Michelle; Dooley, Mary Anne; Fortin, Paul; Gladman, Dafna D; Steinsson, Kristján; Ramsey-Goldman, Rosalind; Khamashta, Munther A; Aranow, Cynthia; Mackay, Meggan; Alarcón, Graciela; Manzi, Susan; Nived, Ola; Jönsen, Andreas; Zoma, Asad A; van Vollenhoven, Ronald F; Ramos-Casals, Manuel; Ruiz-Irastorza, Giuillermo; Lim, Sam; Kalunian, Kenneth C; Inanc, Murat; Kamen, Diane L; Peschken, Christine A; Jacobsen, Søren; Askanase, Anca; Sanchez-Guerrero, Jorge; Bruce, Ian N; Costedoat-Chalumeau, Nathalie; Vinet, Evelyne
OBJECTIVES:To assess the prevalence of combined hormonal contraceptives (CHCs) in reproductive-age women with SLE with and without possible contraindications and to determine factors associated with their use in the presence of possible contraindications. METHODS:This observational cohort study included premenopausal women ages 18-45 years enrolled in the SLICC Registry ⩽15 months after SLE onset, with annual assessments spanning 2000-2017. World Health Organization Category 3 or 4 contraindications to CHCs (e.g. hypertension, aPL) were assessed at each study visit. High disease activity (SLEDAI score >12 or use of >0.5 mg/kg/day of prednisone) was considered a relative contraindication. RESULTS:A total of 927 SLE women contributed 6315 visits, of which 3811 (60%) occurred in the presence of one or more possible contraindication to CHCs. Women used CHCs during 512 (8%) visits, of which 281 (55%) took place in the setting of one or more possible contraindication. The most frequently observed contraindications were aPL (52%), hypertension (34%) and migraine with aura (22%). Women with one or more contraindication were slightly less likely to be taking CHCs [7% of visits (95% CI 7, 8)] than women with no contraindications [9% (95% CI 8, 10)]. CONCLUSION:CHC use was low compared with general population estimates (>35%) and more than half of CHC users had at least one possible contraindication. Many yet unmeasured factors, including patient preferences, may have contributed to these observations. Further work should also aim to clarify outcomes associated with this exposure.
PMCID:6821299
PMID: 30753683
ISSN: 1462-0332
CID: 4874782
Avascular Necrosis Is Associated with APOL1 Variants in African Americans with Systemic Lupus Erythematosus [Meeting Abstract]
Yip, Kevin; Efuni, Elizaveta; Qian, Yingzhi; Clancy, Robert; Buyon, Jill; Blazer, Ashira
ISI:000507466903173
ISSN: 2326-5191
CID: 4645602
Reduced DNASE1L3 activity in sporadic sle is linked to increased dna load of microparticles, reactivity to dnase1l3-sensitive antigens, and Lupus Nephritis [Meeting Abstract]
Hartl, J; Clancy, R; Izmirly, P; Michael, Belmont H; Trad, C; Bornkamp, N; Sisirak, V; Sally, B; Buyon, J; Reizis, B
Background/Purpose : Null mutations in DNASE1L3 cause severe familial SLE with prominent anti-DNA antibodies (Abs), suggesting that DNASE1L3 is a key driver of tolerance to DNA. Indeed, DNASE1L3-deficient mice rapidly develop anti-chromatin and anti-DNA Abs followed by renal involvement. DNASE1L3 is a secreted DNase that has the preferential capacity to digest DNA within nucleosomes and/or encapsulated by membranes. Our previous studies suggest that chromatin carried by circulating apoptotic microparticles (MP) is an important physiological substrate of DNASE1L3. Accordingly, the present study was initiated to address the hypothesis that dysfunction of DNASE1L3 and its downstream consequences contribute to the development of sporadic human SLE. Methods : Reactivity to DNASE1L3-sensitive antigens on MP was measured by incubating plasma samples with control or DNASE1L3-treated MP and analyzing IgG binding to MP by flow cytometry. DNASE1L3 activity was measured based on its preferential capacity to digest complex DNA substrates with the readout expressed as the fraction of activity measured in healthy control subjects. The DNA load of MP was measured by qPCR of genomic DNA purified from the MP and MP-depleted fractions of plasma. In considering a spectrum from benign to clinical autoimmunity, subjects included those with active biopsy proven lupus nephritis as well as those with anti-Ro antibodies absent SLE. Results : IgG-binding to MP was assessed in 116 SLE patients, 45 anti-Ro Ab-positive mothers whose children have neonatal lupus (17 asymptomatic or having an undifferentiated autoimmune syndrome, 2 SLE, 12 SS, 14 SLE/SS) and 16 healthy controls. IgG-reactivity to MP was not detected in any healthy controls. In contrast, 36% of SLE patients showed IgG binding to MP reversed by DNASE1L3 pretreatment (DNASE1L3-senstive reactivity). Only two of these patients were heterozygous for the known hypomorphic DNASE1L3 (R206C) variant. DNASE1L3-sensitive reactivity correlated with anti-dsDNA Abs (p< .0001) but did not overlap, indicating that reactivity is directed to more complex DNA. DNASE1L3-sensitive reactivity correlated with active proteinuria (p=.0003), low complement levels (p=.01) and overall SLEDAI (p< .0001). Among 45 anti-Ro-positive mothers, all were unreactive except the only 2 SLE mothers that developed lupus nephritis. The DNA load of MP and DNASE1L3 activity were assessed in a subset of SLE patients (n=40). Of these, patients with proteinuria showed lower plasma DNASE1L3 activity (p=.034) than those without proteinuria (Fig. 1). Moreover, increased partitioning of plasma DNA into MP correlated with reduced DNASE1L3 activity, and both parameters strongly correlated with DNASE1L3-sensitive IgG binding to MPs (p< 0.0001) (Fig. 2). Conclusion : The activity of plasma DNASE1L3 is reduced in a significant fraction of SLE patients with renal disorder unrelated to a genetic explanation and is associated with DNA accumulation in MP targeted by Abs. Collectively, these data suggest that digestion of circulating chromatin by DNASE1L3 is a fundamental mechanism of tolerance to DNA which when disrupted may lead to sporadic SLE, particularly lupus nephritis
EMBASE:633059048
ISSN: 2326-5205
CID: 4633612
Evaluation of the transcriptome of non-lesional, non-sun exposed skin in patients with lupus nephritis [Meeting Abstract]
Suryawanshi, H; Clancy, R; Der, E; Izmirly, P; Belmont, H M; Putterman, C; Buyon, J; Tuschl, T
Background/Purpose : The impact of renal injury in lupus nephritis (LN) is widespread with consequences to resident cells in other tissue beds, even non-lesional, non-sun exposed skin. Faithful reflection of a relevant renal tissue pathway in a more readily accessible compartment would allow for less invasive diagnostic alternatives. While ongoing studies are exploiting single cell RNA sequencing to link phenotype to biotype and identify cell specific pathways in the kidney, this study was initiated to address the hypothesis that these pathways may be reflected in uninvolved skin which is more likely to be serially biopsied. Methods : Single cell RNAseq was performed on cell suspensions prepared from ~2 mm punch biopsies of nonlesional, non-sun-exposed skin from the buttocks of 5 healthy controls, 4 SLE patients without LN and 18 SLE patients with proteinuria (with skin biopsies obtained within 24 hrs of the kidney biopsy). Histology revealed Class III ( n=6 ), Class III/V or IV/V mixed ( n=11 ), Class V ( n=1 ), and nephrosclerosis ( n=1 ). Dissociation of cryostored skin biopsies with collagenase and trypsin enzymes was followed by scRNA-seq using the 10x Genomics platform using V2 and V3 reagents. Results : We obtained 8,019 and 17,655 high-quality scRNA-seq profiles from single cell suspensions of control and SLE non-lesional, non-sun-exposed skin, respectively. A graph-based clustering method was applied and identified major clusters of cells as visualized by t-distributed stochastic neighbor embedding (tSNE). Differential gene expression analysis guided by established markers revealed these cell clusters as keratinocyte (KC), one smooth muscle cell cluster (SMC), fibroblast (FB), melanocyte (MEL), vascular endothelial cells (VEC), lymphatic endothelial cells (LEC), macrophages-dendritic cells (MAC-DC), T cells (TC) and sweat gland cells (SGC) (Figure 1A). Ranking cells by abundance, the result of the SLE skin cells was KC >FB >VEC >LEC, SMC, MAC-DC, TC, MEL and SGC. Overall, samples processed using the recent V3 single cell reagent kit showed higher genes and transcript captures compared to V2. However, these samples also captured more mitochondrial transcripts (Figure 1B). An analysis of gene expression changes in KC, SMC, and VSC from the LN patients versus controls demonstrated overexpression of interferon stimulated genes. However, the degree of interferon response varied in these cell types with KCs (basal KC, p=0.00312 and hair follicle KC, p=0.000012) showing the highest response followed by VECs (p=0.0043) and SMCs (p=0.0068). In addition to the interferon response signature, VECs from the LN patients also showed upregulation of MHC-II genes such as HLA-DRB5 and HLA-DRB1, suggesting increased antigen presentation capacity (Figure 1C). Conclusion : scRNA-seq identifies major skin cell types and further clustering identifies rarer cell populations. KCs, SMCs, and VECs from the skin of LN patients reveal diverse IFN response states and additionally VECs also show higher antigen presentation potential. The V3 upgrade of 10x Genomics single cell reagents capture more genes and UMIs per cell, but also higher mitochondrial content compared to the V2 version
EMBASE:633058250
ISSN: 2326-5205
CID: 4633772
Assessing commercial titers of anti-Ro60 and RO52 antibodies to risk stratify surveillance of anti-RO/SSA antibody positive pregnancies [Meeting Abstract]
Robins, K; Bhan, R; Trad, C; Cohen, R; Chang, M; Wainwright, B; Masson, M; Mehta-Lee, S; Izmirly, P; Clancy, R; Cuneo, B; Buyon, J
Background/Purpose : Pregnancy counseling of all anti-Ro positive women includes advice regarding the development of congenital heart block (CHB), albeit the risk is only 2% for primigravida women or those with previously unaffected offspring. Despite this low risk, the prevailing surveillance recommendation is weekly echocardiography. While evidence from basic research laboratories support that high titers of antibodies confer clinically meaningful risk, unfortunately the majority of commercial laboratories use the BioPlex assay, which provides positive and negative values with limited information on actual levels because the sera or plasma are not diluted past a specified cutoffgiven cost (e.g. values of anti-Ro inclusive of Ro52 or Ro60 by laboratories such as Quest or LabCorp provide positive as 1-8 or > 8 units with no further information). The present study was initiated to assess whether the Bio-Plex assay used by many commercial laboratories provides adequate stratification of risk for counseling regarding management. Methods : The study group comprised healthy non-pregnant donors (N = 9), healthy pregnant donors (N = 62), women testing positive for anti-Ro by commercial BioPlex but without CHB children (N = 60 SLE and 2 SS), and women with CHB children (N = 83). Anti-Ro60 reactivity was assessed using native antigen and anti-Ro52 using recombinant protein. Sera were applied to coated microtiter plates at serial dilutions ranging from 1:1000 -1:50,000 for 1h at RT and run in duplicate. Tested samples were multiplied by the dilution factor which gives an OD in the range of 0.3-0.8. Results were considered positive at 123 ELISA units (EU) for Ro60 and 215 EU for Ro52 as this represented the mean +3 SD of the values obtained for healthy control sera. Results : Of the 83 CHB mothers tested, 74 had titers of Ro60 and Ro52 > 1000 EU, in 1 anti-Ro60 was > 1000 EU and anti-52 Ro between 215 -1000, in 3 anti-Ro52 was > 1000 EU and anti-Ro60 between 300 -1000, and 1 mother had anti-Ro60 > 1000 EU and was negative for anti-Ro52. Albeit all positive, the sera from 4 CHB mothers obtained 15 years after the birth of the affected child were < 1000 EU for both anti-Ro60 and Ro52. With these results setting thresholds ( > 1000 EU in either Ro60 or Ro52 for CHB risk), we assessed patients testing positive for anti-Ro based on the BioPlex assay. Of 42 patients with values of > 8 on BioPlex testing, 14 had titers > 1000 EU for both anti-Ro60 and Ro52, 7 had anti-Ro60 > 1000 EU, and 8 had anti-Ro52 > 1000 EU. Thus, 13 of 42 (25%) with commercial Ro > 8 did not meet the threshold EU for CHB risk. Of 20 patients considered positive for anti-Ro by BioPlex with values between 1-8, none had levels of either anti-Ro60 or Ro52 at 1000 EU. No patient or healthy control testing negative by the BioPlex assay was positive for CHB risk in our ELISA. Conclusion : These data suggest that commercial testing using the BioPlex assay may fall short of stratifying risk for CHB. Women with positive values < 8 are not likely at risk, obviating the cost and burden of weekly fetal echo surveillance. Moreover, even those considered high titer on commercial testing may be at low risk supporting the need for more quantitative commercial testing than is currently available. (Figure Presented)
EMBASE:633058601
ISSN: 2326-5205
CID: 4633712
Toward a liquid biopsy for lupus nephritis: Urine proteomic analysis of sle identifies inflammatory and macrophage signatures [Meeting Abstract]
Fava, A; Zhang, Y; Buyon, J; Belmont, H M; Izmirly, P; Mohan, C; Zhang, T; Petri, M
Background/Purpose : Lupus nephritis (LN) complicates up to 60% of patients with systemic lupus erythematosus (SLE) and carries a high morbidity and mortality. The definitive diagnosis is based on kidney biopsy. This is invasive and not always readily available, thus delaying treatment. Sometimes multiple biopsies are required over the course of the disease. Importantly, while renal pathology is accurate at describing the morphology of renal disease, the underlying biology and molecular pathways are not thoroughly assessed. Urine proteomics is a non-invasive strategy that may provide insights regarding ongoing renal disease. Methods : One thousand proteins were quantified (RayBiotech Kiloplex assay) on a total of 112 longitudinal urine samples from 32 SLE patients with active LN and 7 healthy controls (HC) enrolled in the Accelerating Medicines Partnership (AMP). All patients underwent treatment as directed by their own physicians. Differentially excreted proteins at baseline (SLE vs HC, proliferative vs membranous LN, responders vs non responders) were identified using a linearmodel with moderated t statistic. Response to treatment was defined based on proteinuria at 1 year as complete (< 0.5g/24h) or partial (50% reduction but >0.5/24h). In the longitudinal analysis, a mixed model was employed to identify markers associated with proteinuria. Pathway enrichment analysis was performed using the genes coding for the differentially excreted analytes using Ingenuity Pathway Analysis (IPA) and other publicly available pathway libraries. Results : There were 186 proteins increased in SLE patients (Fig. 1). The most enriched pathway was TNFa (p< 0.001). We found 74 differentially excreted proteins comparing proliferative and pure membranous LN. CD4, MCP-1, MIP-1a, RANTES, IL-16, and IL-7, markers involved in CD4 T cell and monocyte biology, were enriched in proliferative disease. A few targets were exclusively identified in either class (i.e. CD4 in proliferative nephritis). We used a longitudinal model to identify specific urine proteins associated with worse proteinuria as a marker of severity. Proteinu-ria was associated with 105 markers (FDR < 0.05), the strongest association being CD163 (p = 10-9), a phagocyte marker. IPA implicated several pathways involving fibrosis, acute phase response, LPS/IL1, RXR, ICOS signaling and macrophage/fibroblasts (Fig. 2). Next, we identified 27 differentially excreted proteins in non-responders. IPA revealed that tretinoin, GM-CSF, TNF, and IL1 were among the top upstream regulators (Fig. 3). Conclusion : There is an inflammatory signature in the urine of patients with LN implicating monocyte and TNFa pathways. These signatures are associated with proliferative disease, worse proteinuria, and non-response to treatment. Of note, TNFa is involved in LN and has therapeutic potential. In phase 1 of AMP, monocytes were the main urine cell type identified by singe cell RNA sequencing in patients with LN. These results suggest that urine proteomics might identify and infer active pathological mechanisms in LN, paving the way for a more personalized approach to treatment. Further work in Phase 2 of AMP is being pursued to validate and extend these findings
EMBASE:633058248
ISSN: 2326-5205
CID: 4633782
Single cell transcriptome analysis of circulating plasmacytoid dendritic cells and switched memory B-cells in SLE patients reveals transcriptional subsets within the classical cell lineages [Meeting Abstract]
Puranik, A; Ghodke-Puranik, Y; Tipon, R; Jensen, M; Gupta, A; Paredes, J; Sankaramanchi, U; Nln, I; Saxena, A; Belmont, H M; Izmirly, P; Clancy, R; Buyon, J; Niewold, T
Background/Purpose: Both plasmacytoid dendritic cells (pDCs) and switched memory B cells (SMBCs) are considered to be key effector cells in systemic lupus erythematosus. It seems likely that within these classical cell lineages, additional diversity of function will exist that will contribute to disease pathogenesis. To explore this question, we performed single-cell RNA sequencing in pDCs and SMBCs from SLE patients and controls to assess gene expression patterns and cellular sub-groupings within these lineages. Methods : pDCs and SMBCs from SLE patients (n=10) and Healthy controls (n=5) were purified by magnetic separation. For deep sequencing, we used the Fluidigm C1 HT system with 800 capture site chips to capture single cells. Single cell capture was verified by direct visualization using the Array Scan system, allowing us to remove empty wells and wells with multiple cells. After quality control and adaptor trimming, the data was analyzed using SeqGeq software. pDCs and SMBCs were clustered using UMAP and pseudo-time analysis was performed using the Monocle program. Type I IFN activity in SLE plasma was measured using reporter cell assay. Results : A total of 2774 pDCs and 2578 SMBCs from SLE and healthy controls passed the quality control and were used for further analysis. In pDCs, we observed unique clusters for patients with high interferon, low interferon, and controls, indicating that the IFN response is a major determinant of overall gene expression patterns in SLE patient pDCs. IFN signature in pDCs correlated with circulating type I IFN activity in the SLE patients measured at the same time. Other genes upregulated in pDCs included the type I interferon regulator AXL and MACC1. The SMBCs were heterogeneous in patients and controls, and in contrast to the pDCs, the overall clustering pattern was independent of the IFN score. SMBC clusters were predominantly defined by genes indicating cellular activation or proliferation such as HLA-DRs and CREB1, or genes associated with nucleic acid processing such as DNASE1 and SNORD3B-1. Conclusion : We find distinct clusters of cells defined transcriptionally within the pDC and SMBC lineages, and the transcripts which define these subgroups differ between cell lineages. Type I IFN induced transcripts are important to pDC diversity, while in SMBCs transcripts related to cellular activation and nucleic acid processing are critical markers of transcriptional heterogeneity
EMBASE:633059399
ISSN: 2326-5205
CID: 4633522
Apolipoprotein L1 variant-carrying monocytes exhibit mitochondrial respiration defects [Meeting Abstract]
Blazer, A; Chang, M; Robins, K; Buyon, J; Clancy, R
Background/Purpose : In SLE Apolipoprotein L1 (APOL1) risk variants associate with cardiovascular and kidney damage. APOL1 is both a secreted and tissue intrinsic protein; the latter role mediates organ injury. Expression is driven by inflammatory stimuli which initially promotes survival through autophagy. At higher expression, APOL1 contributes to cell death partially by compromising mitochondria. The RV protein structure favors toxicity at lower thresholds. Macrophages express APOL1 and use metabolic plasticity to perform effector functions. We hypothesized that in activated macrophages, APOL1 expression impairs mitochondrial Methods : Healthy controls were genotyped for APOL1 reference allele (G0) risk variants (RV) (n=15; G0/G0=8, RV/ G0=4, RV/RV=3). Monocytes were isolated from PBMCs using a Miltenyi Biotec Pan Monocyte Isolation kit and differentiated into macrophages using GM-CSF. Cells were treated with SLE-relevant agonists ssRNA hY3 or IFNgamma; and APOL1 expression was observed by qPCR. As in-vivo correlates, APOL1 expression relative to IFN response gene, Siglec 1, in SLE patient monocytes (n=17); and expression in coronary artery tissue macrophages with (n=3) or without (n=3) atherosclerotic plaque were assessed through RNA seq data and immunohistochemistry respectively. To test mitochondrial respiration, cultured HC macrophages were left untreated or IFNgamma treated, and bioenergetics were measured by the Seahorse assay. Confirmatory fluorescent microscopy was done by staining cells with Mitoprobe (polarized mitochondria) and Mitotracker (all mitochondria) and the ratio of Mitoprobe to Mitotracker staining was quantified using ImageJ software. Results : Across the genotypes,hY3 and IFNgamma increased APOL1 mRNA expression 29.1+/-18.4 and 31.6+/-14.9 fold compared to untreated (p< 0.001 in each). In SLE monocytes, APOL1 significantly correlated with Siglec1 expression (R=0.64; P=0.005). APOL1 stained 4% of non-plaque containing and 18% of plaque-containing coronary arteries (p=0.05). APOL1 was apparent in multiple cell types including invading tissue macrophages (fig1). On the seahorse assay, there were genotype-dependent differences in Basal OCR (BO pmol/min), Spare Capacity (SC pmol/min), and total ATP production (ATP pmol/min) (G0/G0: BO: 99.4+/-11.3, SC:150.9+/-16.6, ATP: 88.1+/-9.5; RV/G0: BO: 46.1+/-4.5, SC: 52.1+/-8.8, ATP: 40.7+/-3.4; RV/RV: BO: 46+/-17.4, SC: 14.9+/-11.6, ATP: 36.7+/-9.5 each p< 0.001). Across genotype, these values fell with IFNgamma (G0/G0: BO: 73.9+/-6, SC: 129.4+/-17.3, ATP: 67.6+/-5.4; RV/G0: BO: 46+/-5.1, SC: 27.9+/-8.1, ATP: 39.5+/-3.9; RV/RV: BO: 42.1+/-8.6, SC: 9.5+/-8.3, ATP: 35.8+/-6.9) (fig2). Fluorescent microscopy confirmed findings with the mean respective MitoProbe/Mitotracker ratios in G0/G0, RV/G0, and RV/RV macrophages at rest 1.5+/-0.5, 0.86+/-0.3, and 0.89+/-0.3 and with IFNgamma 1.3+/-0.4, 0.74+/-0.3, and 0.6+/-0.2 (fig3). Conclusion : Inflammation both in vitro and in vivo due to hY3, IFNgamma, and ischemia increase macrophage APOL1 expression across genotypes. In RV carrying macrophages, this results in diminished mitochondrial energy production-a potential underpin of variant-mediated toxicity. (Figure Presented)
EMBASE:633058566
ISSN: 2326-5205
CID: 4633722
Zipcode-binding protein 1 (ZBP1) facilitates RO60 surface translocation, cellular growth and autoimmune sequelae [Meeting Abstract]
DiDonato, F; Buyon, J; Clancy, R
Background/Purpose : Despite the strong association of maternal anti-Ro60 autoantibodies in the development of SS, Neonatal Lupus (NL) and scLE, understanding causality is challenging given that the intracellular location of the target RNP antigen only becomes accessible to extracellular autoantibodies during cell death. While binding Y RNA is a property of Ro60 in dying cells, Ro60 contributes to events essential to proliferation including the degradation of non-coding RNAs. To define potentially targetable molecular events associated with Ro60 accessibility and their effects on proliferation, we evaluated two candidate chaperone Ro60 binding proteins, ZBP1 (also known as IGF2BP1, which has two RNA recognition domains and plays a role in nuclear export of protein) and PTBP1 (which binds RNA in heterogeneous nuclear complexes). Methods : Short hairpin (sh)RNA knockdown (KD) of both ZPB1 and PTBP1 was accomplished by using MISSION pLKO.1 derived lentiviral vehicles for targeted shRNA to yield each of the specific depletions in human fetal fibroblasts. Affinity purified anti-Ro60 antibodies (AP60) isolated from the serum of 2 mothers of children with cardiac NL and control IgG isolated from a healthy donor were used to evaluate Ro60 surface translocation in intact and apoptotic cells by flow cytometry. Fibroblast proliferation was determined using 5-ethynyl-2'-deoxyuridine (EdU) incorporation. Results : KD of targeted transcripts were confirmed by qPCR and western blot. Permeabilized KD and wildtype fi-broblasts demonstrated equivalent intracellular expression of Ro60. As expected, flow cytometry with AP60 revealed no surface staining of non-permeabilized wildtype or KD fibroblasts. The next set of experiments addressed binding of AP60 to polyHEMA-apoptotic fibroblasts. Staining with annexin V (a proxy of apoptosis) was uniformly consistent between the wildtype and KD cells. As expected, compared to non-apoptotic fibroblasts, AP60 but not control donor IgG readily bound the surface of wildtype apoptotic fibroblasts, supporting that Ro60 was indeed translocated during apoptosis (MFI of 97 + 5 vs 211 + 14, respectively; P< 0.05; N=3). In contrast, binding of AP60 was significantly attenuated in the ZPB1 KD fibroblasts (81.5 + 7; N = 3) vs anti-Ro binding of apoptotic wildtype fibroblasts(P< 0.05). However, the binding of AP60 was equivalent in the apoptotic PTBP1 KD fibroblasts (MFI of 203 + 6, N= 3, P=NS) compared to apoptotic wildtype fibroblasts. With regard to cell proliferation, the percent positive EdU cells of wildtype fetal fibroblasts, ZBP1 KD fibroblasts, and PTBP1 KD fibroblasts were 56%, 2% and 45%, respectively, a result suggesting that the loss of ZBP1 restrains cell cycle progression. Conclusion : ZBP1 represents a novel and required chaperone for the translocation of Ro60 to the cell surface during apoptosis in addition to contributing to cell proliferation. Given that Ro60 antigen accessibility is essential, not only to the generation of anti-Ro60 responses but also to the formation of surface immune complexes and subsequent tissue injury, ZBP1 may represent a newly targetable candidate to forestall both the initiation and sequelae of autoimmunity
EMBASE:633059242
ISSN: 2326-5205
CID: 4633562
A tale of three cohorts: SLE criteria in developed vs developing countries [Meeting Abstract]
Blazer, A; Guttmann, A; Dzifa, Dey I; Ayanlowo, O; Ima-Edomwonyi, U; Olasebikan, H; Reynolds, M; Ankrah, F; Buyon, J; Adelowo, O
Background/Purpose : SLE diagnostic criteria are important for reliable epidemiologic data. The prevalence of SLE in West Africa is falsely low due to barriers including limited access to both resource and labor-intensive diagnostic testing. Recently, the ACR and EULAR have proposed a weighted classification tool which is thought to improve diagnostic sensitivity and specificity compared to the established ACR and SLICC criteria. Here we aim to investigate the performance of each classification criteria in two West African cohorts--Korle bu Teaching Hospital, Accra Ghana (GH); and Lagos University Teaching Hospital, Lagos, Nigeria (N)--compared to an NYU Langone-African American (AA) cohort. Methods : We collected data on a total of 355 SLE patients: AA: n=151, GH: n=110, and N: n=94, diagnosed by expert clinicians. Clinical information including demographics, SLE criteria, SLEDAI scores, SLICC damage indexes, vital signs, and laboratory values as available was obtained at the initial patient encounter. Longitudinal data was collected over the course of at least 1 year at 6 month intervals during routine clinical visits. Where necessary, clinical charts were retrospectively reviewed, and the proportion of patients in each cohort meeting ACR, SLICC and the ACR/EULAR classification criteria was calculated. Results : The demographics per cohort were as follows: Age (in yrs): AA=43.1, GH=32.4yrs, N=35.5; percent female: AA=90, GH=100, N=97; Mean SLE disease duration (yrs): AA=14.3, GH=2.2, N=4.4. In each cohort, the percentage of patients meeting ACR, SLICC, and ACR/EULAR criteria were AA=96%, 96%, and 95%; GH=85%, 84%, 62%; N=90%, 87%, 61%. This discrepancy was largely due to missing laboratory data particularly with regard to immunologic and hematologic studies. ANA was missing in 0% of the AA cohort, 26% of the GH cohort, and 33% of the N cohort respectively. Compared to the GH and N cohorts, the reference AA cohort was more likely to meet ACR, SLICC, and ACR/EULAR criteria with likelihood ratios (LR) of GH=10.2 p< 0.001 and N=3.0 p=0.08; GH=11.5, p< 0.001 and N=6.3, p=0.01; and GH=46.1 P< 0.001 and N=44.9, p< 0.001 respectively. On average, the mean number of ACR/EULAR points by cohort was AA: 26.1+/-11.8, GH: 21.3+/-8.1, and N: 19.0+/-6.2. While the ANA entry criteria greatly diminished the new ACR/EULAR diagnostic utility in the GH and N cohorts, the weighted point system performed better than either of the ACR or SLICC criteria with 96% of the AA cohort, 92%of the GH, and 95% of the N cohort meeting criteria (LR: AA vs GH=1.9, p=0.2; AA vs N=0.23, p=0.6). Conclusion : Due to a relative lack of resources, supportive laboratory assays including an ANA may be more difficult to attain in developing nations. SLE is a clinical syndrome that may be efficiently diagnosed using the new weighted ACR/EULAR criteria. The entry criteria of ANA 1:80 greatly diminished the diagnostic utility of this classification system in the Ghanaian and Nigerian cohorts compared to the African American cohort. Clinical trials should consider offering wide ANA testing to cohorts in the developing world
EMBASE:633059866
ISSN: 2326-5205
CID: 4633442