Faculty Bibliography

Photosensitivity, or skin sensitivity to ultraviolet radiation (UVR), is a feature of lupus erythematosus (LE) and other autoimmune and dermatologic conditions. Photosensitivity is associated with increased keratinocyte apoptosis, but mechanisms that modulate keratinocyte apoptosis that are dysfunctional in photosensitivity are poorly understood. Here, we identify a Langerhans cell (LC)-keratinocyte axis that limits UVR-induced keratinocyte apoptosis and skin injury via keratinocyte epidermal growth factor receptor (EGFR) stimulation. LCs express EGFR ligands and ADAM17, the metalloprotease that activates EGFR ligands. LC ADAM17 is required for skin protection and is activated by UVR, suggesting that LCs protect by providing activated EGFR ligands to keratinocytes. Photosensitive systemic LE (SLE) models have reduced LC ADAM17, and topical EGFR ligand reduces photosensitivity. Human SLE skin shows reduced EGFR activation. Together, our data identify a new tissue protective function for LCs, delineate a novel mechanism that limits skin injury, and suggest EGFR stimulation as a treatment for photosensitivity and possibly other dermatologic conditions.
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Photosensitivity, or skin sensitivity to ultraviolet radiation (UVR), is a feature of lupus erythematosus and other autoimmune and dermatologic conditions, but the mechanistic underpinnings are poorly understood. We identify a Langerhans cell (LC)-keratinocyte axis that limits UVR-induced keratinocyte apoptosis and skin injury via keratinocyte epidermal growth factor receptor (EGFR) stimulation. We show that the absence of LCs in Langerin-diphtheria toxin subunit A (DTA) mice leads to photosensitivity and that, in vitro, mouse and human LCs can directly protect keratinocytes from UVR-induced apoptosis. LCs express EGFR ligands and a disintegrin and metalloprotease 17 (ADAM17), the metalloprotease that activates EGFR ligands. Deletion of ADAM17 from LCs leads to photosensitivity, and UVR induces LC ADAM17 activation and generation of soluble active EGFR ligands, suggesting that LCs protect by providing activated EGFR ligands to keratinocytes. Photosensitive systemic lupus erythematosus (SLE) models and human SLE skin show reduced epidermal EGFR phosphorylation and LC defects, and a topical EGFR ligand reduces photosensitivity. Together, our data establish a direct tissue-protective function for LCs, reveal a mechanistic basis for photosensitivity, and suggest EGFR stimulation as a treatment for photosensitivity in lupus erythematosus and potentially other autoimmune and dermatologic conditions.

Background There are no longitudinal studies regarding thelong term cardiac health of children with cardiac manifestations of neonatal lupus (NL). This study was performed toevaluate risk factors for morbidity and provide evidence-basedguidance regarding the course of cardiac NL.Methods Echocardiograms throughout life were evaluated in240 individuals born with cardiac NL from the ResearchRegistry for Neonatal Lupus: 142 were available from ages 0 1 years, 174 from ages 1 17 years, and 65>17 years. A composite adverse outcome defined as qualitatively decreased leftventricular (LV) function or concurrent use of cardiac medications was assessed. Aortic dilation (root or ascendingaorta z-score >2.0) was also recorded. Analyses were performed to associate the composite adverse outcome and aorticdilation with maternal medications, pacing, and fetal diseasestatus, including a severity score based on mortality risk factors such as lower fetal heart rate and extranodal disease.Results The composite adverse outcome for cardiac dysfunctionwas identified in 21.1% of echos in children ages 0 1, 13.2% ages1 17% and 29.2% ages>17. In 89 children in which echos wereavailable at ages 0 1 and 1 17, 6/16 with dysfunction at ages 0 1were also affected at ages 1 17, while 10 reverted to normal.Among those without dysfunction at age 0 1, 8/90 developednew worsening of cardiac function during age 1 17. In 35 caseswith echos at ages 1 17 and >17, 3/3 cases with dysfunction atage 1 17 were also affected at >17, and 2/32 developed new dysfunction in adulthood. Cardiac dysfunction was significantly associated with number of years paced at all ages (p<0.001, 0.001,<0.001). A lower fetal ventricular heart rate at the first time ofheart block detection was associated with cardiac dysfunction age0 1 and >17 (p=0.048, 0.005 respectively) and lowest heart ratein utero associated with dysfunction at age <1 and 1 17(p<0.001, 0.015). Fetal extranodal cardiac disease was associatedwith dysfunction in ages1 17 and >17 (p=0.026, 0.023). Higherfetal severity score associated with postnatal dysfunction in ages0 1 and 1 17 groups (p=0.013, 0.001). Aortic dilation waspresent in 13.4% at ages 0 1% and 14.9% at ages 1 17, butat >17, dilation only occurred in 9.2%. There was no associationof postnatal cardiac dysfunction or aortic dilation with maternalmedication use, maternal rheumatic disease, fetal age at heartblock detection or gestational age of birth.Conclusions Cardiac dysfunction in the first year normalizesby later childhood in the majority of cases, possibly due tothe short term effects of cardiac pacing or resolution ofinflammation with the clearance of maternal autoantibodies.However, new onset dysfunction can occur after the first yearof life. Aortic dilation can continue for longer periods, butmay decrease in frequency with age. Nevertheless, cardiac dysfunction is present in roughly 30%, and in adulthood thereare associations with fetal extranodal disease and heart rate atdetection. Patients who develop morbidity in utero may havesubclinical damage or be more susceptible to future insultsthat manifest later in life, which can be exacerbated by prolonged pacing. Close monitoring and aggressive treatment ofearly extranodal disease in cardiac NL may have long termbenefit in preventing subsequent morbidity

Background Missing data due to drop-out and loss to followup is a common problem in SLE trials. The usual approachesfor handling this issue include analyzing only subjects withcomplete data (complete case analysis; CC), last observationcarried forward (LOCF), or imputing non-responses for missing outcomes (non-responder imputation; NRI). However, thevalidity of these methods depends on strong assumptionsabout the missing data mechanism. Multiple imputation (MI)is a flexible model-based technique that accounts for uncertainty in the imputation process by generating several possiblevalues for the missing data, resulting in multiple completedata sets. These are analyzed separately and results are combined. MI is being used more widely in different disease settings but has not been applied to analyze the primaryoutcome in a SLE trial. We explored the use of MI to addressmissing data in the composite outcome, SLE Responder Index(SRI)-5, using data from patients assigned to standard of care(SoC) in a 52 week trial.Methods Data on 279 SLE patients randomized to SoC for 52weeks who were receiving mycophenolate mofetil (MMF), azathioprine, or methotrexate at entry were obtained from theLupus Foundation of America-Collective Data Analysis Initiative database. Multiple imputation using chained equationswas applied to handle missing data in an analysis to evaluatedifferences in SRI-5 response rates at 52 weeks betweenpatients on MMF and the other immunosuppressants (nonMMF). Three different imputation models were consideredthat included various combinations of longitudinal measures ofdisease activity (both composite and individual measures) andpatient characteristics. Results were compared to estimatesusing the CC, LOCF, and NRI.Results Missing data rates were 32% in the MMF and 23%in the non-MMF groups. As expected, the NRI missing dataapproach yielded the lowest response rates; the smallest andleast significant estimates of between group differences wereobserved with LOCF (table 1). Group differences were magnified with all three MI models compared to results of othermethods. Imputing SRI-5 directly (MI-1) versus the individualcomponents (MI-2) yielded nearly identical results.Conclusions Given the limitations of conventional approachesfor handling missing data, the MI method should also be considered in SLE trials. However, results can vary depending onthe imputation model that is used, and the assumptionsrequired for validity of this and other missing data methodsmust be justified. Sensitivity analysis using different approachesis important to demonstrate robustness of results especiallywhen missing data rates are non-negligible

Background Although hydroxychloroquine (HCQ) is a mainstay of treatment for patients with Systemic Lupus Erythematosus (SLE), ocular toxicity can result from accumulatedexposure. The introduction of highly sensitive tools has engendered even more concern. As the longevity of patients withSLE improves, additional data will help physicians accuratelybalance the risk of ocular toxicity and the risk of diseaseflare, especially in older patients who have stable/quiescent disease. Accordingly, this study was initiated to examine thesafety of HCQ withdrawal in older SLE patients.Methods Data were obtained by retrospective chart review atthree lupus centers. Twenty-seven patients met the following inclusion criteria:-4 ACR criteria, disease duration-5 years, HCQuse of 200 400 mg per day-5 years, and discontinuation ofhydroxychloroquine at-age 55 years. The comparator groupcomprised 39 age, gender and racial/ethnic matched patients whoremained on HCQ. The primary outcome was a clinically meaningful flare within one year of HCQ withdrawal, defined asmoderate or severe, using a revised version of the SELENA-SLEDAI Flare composite that separates mild from moderate flares,evaluates each organ system separately, and incorporates increasesin corticosteroid dose and/or addition of immunosuppressiveagents. Mild flares were considered secondary outcomes.Results Demographics are provided in table 1. There was atrend toward longer disease duration in the HCQ withdrawalgroup but no difference in prevalence of prior lupus nephritisbetween the groups. The reasons for HCQ withdrawal weremaculopathy (n=13), presumed/biopsy proven cardiomyopathy(n=2), patient request (n=4), and miscellaneous other reasons(n=8). There was no difference in the primary or secondaryoutcomes between the groups (table 1). Two patients had amoderate flare after discontinuing HCQ, of whom one hadarthritis treated with methotrexate and one had thrombocytopenia (>30K) and proteinuria of 2 grams/d (baseline 700 mg).Three patients had severe flares while continuing HCQ, ofwhom two were hospitalized, one for seizures and one forpericarditis; the third had worsening nephritis (urinaryprotein >4 g/d, requiring treatment). Two patients had moderate flares while remaining on HCQ, one of whom had a rashand arthritis treated with tofacitinib and one a rash treatedwith prednisone.Conclusions In this retrospective study of older patients withSLE on long-term HCQ, withdrawal did not increase the riskof moderate or severe flares. These data provide reassuranceregarding the safety of withdrawing HCQ in stable older SLEpatients

Nonadherence to treatment is a major cause of lupus flares. Hydroxychloroquine (HCQ), a major medication in systemic lupus erythematosus, has a long half-life and can be quantified by HPLC. This international study evaluated nonadherence in 305 lupus patients with flares using drug levels (HCQ<200ng/ml or undetectable desethylchloroquine), and self-administered questionnaires (MASRI<80% or MMAS-8<6). Drug levels defined 18.4% of the patients as severely nonadherent. In multivariate analyses, younger age, non-use of steroids, higher BMI and unemployment were associated with nonadherence by drug level. Questionnaires classified 39.9% of patients as nonadherent. Correlations between adherence measured by questionnaires, drug level, and physician assessment were moderate. Both methods probably measured two different patterns of nonadherence: self-administered questionnaires mostly captured relatively infrequently missed tablets, while drug levels identified severe nonadherence (i.e., interruption or erratic tablet intake). The frequency with which physicians miss nonadherence, together with under-reporting by patients, suggests that therapeutic drug monitoring is useful in this setting.

OBJECTIVES: The presence of tubulointerstitial damage (TID) on renal biopsy is considered to be a late sequela of lupus nephritis (LN). The objective of this study was to determine if TID predicts progression to end stage renal disease (ESRD) in LN patients without advanced kidney disease. METHODS: All SLE patients with an index biopsy consistent with LN between January 2005 and July 2015, and eGFR >/= 30mL/min/1.73m2 were included. Moderate-to-severe TID was defined as the presence of moderate-to-severe tubular atrophy and/or interstitial fibrosis. Time to ESRD was defined as time from the index biopsy date to incident ESRD date; non-ESRD patients were censored at the time of death or the last visit before December 2015. Time-dependent analyses were conducted to evaluate whether moderate-to-severe TID was predictive of ESRD progression. RESULTS: Of the 131 LN patients with eGFR >/= 30mL/min/1.73m2, 17 (13%) patients progressed to ESRD. Moderate-to-severe TID was present in 13% of biopsies with eGFR >/= 60mL/min/1.73m2 and in 33% of biopsies with eGFR between 30 and 60mL/min/1.73m2. Moderate-to-severe TID was associated with a higher risk of ESRD progression: adjusted hazard ratio (HR) = 4.1, 95% CI: 1.4-12.1, p = 0.01 for eGFR >/= 30mL/min/1.73m2; HR = 6.2, 95% CI: 1.7-23.2, p = 0.008 for eGFR >/= 60mL/min/1.73m2. There was no association between tubulointerstitial inflammation (TII) and ESRD progression. CONCLUSIONS: Moderate-to-severe TID, but not TII, was a strong predictor of ESRD progression independent of eGFR or glomerular findings, therefore, providing an important window for potential early interventions.