Faculty Bibliography

OBJECTIVE: To study the membrane expression of endothelial protein C receptor (mEPCR) in the renal microvasculature in lupus nephritis (LN) as a potential marker of injury and/or prognostic indicator for response to therapy. METHODS: mEPCR expression was analysed by immunohistochemistry in normal kidney and in 59 biopsies from 49 patients with LN. Clinical parameters were assessed at baseline, 6 months and 1 year. RESULTS: mEPCR was expressed in the medulla, arterial endothelium and cortical peritubular capillaries (PTCs) in all biopsies with LN but not in the cortical PTCs of normal kidney. Positive mEPCR staining in >25% of the PTCs was observed in 16/59 biopsies and associated with poor response to therapy. Eleven (84.6%) of 13 patients with positive staining for mEPCR in >25% of the PTCs and follow-up at 6 months did not respond to therapy, compared with 8/28 (28.6%) with mEPCR staining in < or =25% PTCs, P = 0.0018. At 1 year, 10 (83.3%) of 12 patients with positive mEPCR staining in >25% of the PTCs did not respond to therapy (with two progressing to end-stage renal disease) compared with 8/24 (33.3%) with positive staining in < or =25% of the PTCs, P = 0.0116. Although tubulo-interstitial damage (TID) was always accompanied by mEPCR, this endothelial marker was extensively expressed in the absence of TID suggesting that poor response could not be attributed solely to increased TID. mEPCR expression was independent of International Society of Nephrology/Renal Pathology Society class, activity and chronicity indices. CONCLUSION: Increased mEPCR expression in PTCs may represent a novel marker of poor response to therapy for LN

OBJECTIVE: To evaluate the frequency of anti-alpha-enolase antibodies in the sera of mothers whose children have congenital heart block (CHB), given provocative results in which alpha-enolase, a membrane protein, was recognized by monoclonal antibodies reactive with the peptide p200 of 52 kDa Ro/SSA in a neonatal rat heart library. METHODS: An ELISA using a recombinant alpha-enolase protein was developed. Sera from 100 anti-Ro52+ CHB mothers in the Research Registry for Neonatal Lupus, 50 patients with systemic lupus erythematosus (SLE; 7 anti-Ro52+), and 48 healthy controls were tested for anti-alpha-enolase reactivity. RESULTS: There were no significant differences in the median values obtained from CHB mothers, patients with SLE, or controls at each of the dilutions tested. Only 7 (7%) at 1:100 dilution and 2 (2%) at 1:1000 dilution of 100 CHB sera were 3 standard deviations above the mean value obtained for controls. Preincubation with recombinant Ro52 did not inhibit anti-alpha-enolase reactivity. CONCLUSION: The low frequency of anti-alpha-enolase antibodies in the sera of CHB mothers and the absence of apparent cross-reactivity with Ro52 suggest that antibodies to Ro52 are not likely to mediate CHB via binding to alpha-enolase

OBJECTIVE: To evaluate responses to mycophenolate mofetil (MMF) and intravenous cyclophosphamide (CYC) in lupus nephritis in a multiethnic population. METHODS: This was a retrospective study of all patients with systemic lupus erythematosus (SLE) that underwent kidney biopsy at New York University Medical Center. Patients with followup of at least 6 months were included. Clinical response was defined as complete (return to +/- 10% of normal) or partial (improvement of 50% in abnormal renal measurements). RESULTS: Ninty-nine patients were included in the study: 86% females, 86% non-Caucasian, age 34.2 +/- 1.1 years, 62% with proliferative nephritis (PN; ISN/RPS-III and IV), and 32% with membranous nephritis (MN; ISN/RPS-V). Of the 70 patients with PN, 37 were treated with CYC and 33 with MMF. The baseline characteristics of the 2 treatment groups were different in the incidence of ISN/RPS-IV, values of serum creatinine and serum albumin, and type of insurance (p < 0.05). The response rate was greater in the MMF than in the CYC group (70% vs 41%). Responses to MMF were different in Asians (11/11), Caucasians (4/5), African Americans (3/5), and Hispanics (5/11). Responses to CYC had a similar distribution (Asians 6/10, Caucasians 4/5, African Americans 4/9, Hispanics 1/11). In the MN group (N = 23) responses were similar to the PN group (73% MMF and 38% CYC). After adjusting for race, serum creatinine, serum albumin, type of insurance, and class of nephritis, in a logistic regression model, response to MMF was superior to CYC: OR 6.2 (95% CI 1.9-20.2). Hispanics had worse outcome than Caucasians (OR 0.17). Longterm followup suggested no difference in maintenance with MMF or CYC. CONCLUSION: After controlling for the fact that less severe nephritis is preferentially treated with MMF, we found overall that response to MMF was superior to CYC. In this US population, ethnicity was observed to have an influence on response

OBJECTIVE: Individualized therapy based on genetic background and monitoring of metabolites can optimize drug safety and efficacy. Such an approach is available for azathioprine (AZA), the thiopurine antimetabolite. AZA exerts therapeutic effects when metabolized to the active thiopurine nucleotide, 6-thioguanine (6-TGN). In inflammatory bowel disease (IBD), 6-TGN levels in the target range of 235-400 pmol/8x10(8) red blood cells (RBC) are associated with a high likelihood of response. Our objective was to evaluate whether drug escalation based on metabolite levels improves efficacy and maintains safety in patients with systemic lupus erythematosus (SLE). METHODS: We conducted a 6-month open-label dose-escalation clinical study of patients with active SLE treated with azathioprine dosed by body weight and metabolite levels. The primary endpoint was >or=50% improvement in any one parameter of disease activity, or 50% decrease in glucocorticoid dose. RESULTS: Of 50 patients enrolled in the study, 21 achieved clinical responses, 13 of whom had 6-TGN<235 pmol/8 x10(8) RBC. Ten patients had no clinical response at 6 months, yet achieved either therapeutic IBD 6-TGN levels (>235, n=4) or received maximum AZA dose>or=3.5 mg/kg (n=6). In 19 patients the drug was discontinued prematurely due to side effects or SLE activity. For those patients in whom either liver function test or white blood cell count abnormalities were encountered, metabolites guided attribution to drug or disease activity. CONCLUSION: Clinical responses in SLE can occur at levels of 6-TGN lower than the target range established for IBD. During followup, measurements of AZA metabolites may provide a rational approach to safety

Purpose: The mechanisms underlying premature atherosclerosis in SLE are not understood. The endothelium merits focus since it provides the physiologic boundary which limits extravasation and diapedesis of inflammatory cells. Methods: One hundred and nineteen patients with SLE, predominantly non-Caucasian, and 71 healthy controls matched for age, sex and race, underwent carotid ultrasonography and donated blood for evaluation of circulating endothelial cells (CEC), soluble endothelial protein C receptor (sEPCR) and gene polymorphism at A6936G, soluble E-selectin, and adiponectin. Results: Carotid plaque was more prevalent among patients than controls (43% vs 17%, p=0.0002). Mean CCA IMT was greater in patients compared to controls (0.59mm+/-0.19 vs 0.54mm+/-0.11, p=0.03). Levels of CEC (19 vs 3 CECs/mL, p<0.0001) and sE-selectin (64 vs 36 ng/ml, p<0.0001) were significantly elevated in patients compared to controls. Unexpectedly, adiponectin was also significantly higher in patients compared to controls (16 ug/mL versus 11 ug/mL, p=0.0001) but no differences were seen in the levels of sEPCR or the distribution of genotype. Independent predictors of plaque status using logistic regression models included: age (p<0.0001; OR=2.1 per 10 year increase; 95% CI: 1.5-3.0), SLE status (p=0.015; OR=3.4 for SLE vs control; 95% CI: 1.3-9.1), sE-selectin (p=0.016; OR=1.2 per 10 unit increase; 95% CI: 1.0-1.4) and adiponectin (p=0.050; OR=1.5 per 10 unit increase; 95% CI: 1.0-2.4). Comparing SLE patients with and without plaque, there were no differences in cardiac CRP, complement, anti-dsDNA ab, CEC, sEPCR levels and EPCR SNP. However, sE-selectin and adiponectin levels were significantly higher in SLE with plaque compared to those without (sE-selectin 78 vs 52 ng/ml; p=0.006; adiponectin 18 vs 14 ug/ml; p=0.033). The estimated odds ratios for plaque in the final logistic regression model were: OR_selectin= 1.3 per 10 ng/ml increase (95% CI: 1.1-1.5) and OR_adiponectin=1.8 per 10 ug/ml increase (95% CI: 1.1-3.0). SELENA-SLEDAI scores were similar between groups, and the proportion of patients with SLEDAI<= 4 did not segregate with the absence of plaque. Neither past nor current medications significantly associated with plaque. In the stable subjects (SLEDAI <=4), age (p=0.007), sE-selectin (p=0.02) and adiponectin (p=0.02) remained associated with plaque. The prevalence of plaque was greatest in the stable patients with high sE-selectin plus high adiponectin (55%; p =0.0009) confirming the multivariable analyses. Sixty-two patients donated blood at a second visit. High sE-selectin and adiponectin were sustained in plaque patients compared to non-plaque patients (p=0.0009 and p=0.0011 respectively). Conclusion: These results confirm that SLE patients, irrespective of race, are at increased risk for premature atherosclerosis and support the hypothesis that endothelial perturbation is contributory even in the absence of clinically measurable disease activity

Background: The recurrence rate of anti-SSA/Ro associated congenital heart block (CHB) is 17%. Reversal of 3^rd degree block has never been achieved. Prophylactic IVIG was considered based on two presumed mechanisms of efficacy, a) saturation of FcRn to accelerate maternal IgG catabolism and decrease placental transport b) elevation of macrophage FcRIIB expression to attenuate inflammatory fetal responses. Purpose: To evaluate IVIG efficacy and safety as a preventive therapy for CHB. Methods: A multicenter open-label study based on Simon's 2-stage optimal design was initiated. Enrollment criteria included: maternal anti-SSA/Ro antibody, a previous child with CHB/rash, nd or 3^rd degree CHB in three fetuses. Results: Twenty mothers were enrolled. Sixteen children had normal PR intervals throughout the study and no manifestations of neonatal lupus. One child developed a transient rash consistent with neonatal lupus and had normal PR intervals during pregnancy and normal EKG at birth. However, the pre-determined stopping rule was reached. CHB was detected in three fetuses, at 19, 20 and 25 weeks; none followed an abnormal PR interval. One of these mothers had two previous children with CHB. Antibody titers assessed before every IVIG infusion, and at 28 wks, 34 wks and delivery were compared with values obtained at baseline. No significant changes in maternal antibody titers to SSA/Ro, SSB/La, or Ro52 were detected over the course of therapy or at delivery (P>0.05 for all comparisons). There were no changes in maternal blood pressure, severe headaches, rashes, fever or any other adverse effects related to the infusions. Neonatal weight, height, and head circumference were derived from gestational age -specific growth curves to correct for prematurity when necessary. Four (21%) of the newborns, two with CHB and two healthy, were small for gestational age (<10th centile) and 3 healthy babies (16%) were born prematurely (<37 weeks of gestation). Conclusion: IVIG at doses consistent with replacement does not prevent the recurrence of CHB or reduce maternal antibody titers. Having established safety with this protocol and feasibility of patient enrollment, subsequent studies should address the efficacy of IVIG at higher doses to exploit an anti-inflammatory effect

OBJECTIVES: Reactivation of Mycobacterium tuberculosis (TB) is a significant problem with all available tumor necrosis factor (TNF) antagonists when used to treat rheumatoid arthritis (RA), psoriatic arthritis, psoriasis and other inflammatory diseases. Concerns have been raised regarding the appropriate management of patients with latent TB (LTB) exposure (or active TB infection) before initiating TNF antagonists since the safety data of combined therapy with two potentially hepatotoxic medications, methotrexate (MTX) and isoniazid (INH), is lacking. The goal of this study was to investigate the toxicity of MTX and INH therapy in RA patients before initiating TNF antagonists. METHODS: To investigate the toxicity of MTX and INH therapy in RA patients we performed a retrospective chart review of patients seen at the Bellevue Hospital Arthritis Clinic in New York City between 2002-2006. Forty-four patients who were concomitantly treated with both drugs were included. The primary outcome investigated was increase in liver function tests (LFT). RESULTS: Transient increases in LFT were seen in 11% of patients, but in no case was this more than twice the upper limit of normal values. All abnormal LFT resolved spontaneously without intervention. In addition, no patient has developed signs or symptoms of TB reactivation. CONCLUSION: The use of INH for LTB was well tolerated in RA patients on a background regimen of MTX. While the risks and benefits of all therapy must always be considered, in our experience the additive risk of INH to MTX in terms of hepatotoxicity was low. Nonetheless it is prudent to follow LFT closely on patients taking this combination

OBJECTIVE: Identification of isolated congenital heart block (CHB) predicts, with near certainty, the presence of maternal anti-SSA/Ro antibodies; however, the 2% incidence of CHB in first offspring of anti-SSA/Ro+ mothers, 20% recurrence in subsequent pregnancies, and discordance in identical twins suggest that an environmental factor amplifies the effect of the antibody. Accordingly, this study was carried out to explore the hypothesis that hypoxia potentiates a profibrosing phenotype of the fetal cardiac fibroblast. METHODS: Evidence of an effect of hypoxia was sought by immunohistologic evaluation of CHB-affected fetal heart tissue and by determination of erythropoietin levels in cord blood. The in vitro effect of hypoxia on gene expression and phenotype in fibroblasts derived from fetal hearts and lungs was investigated by Affymetrix arrays, quantitative polymerase chain reaction (PCR), immunofluorescence, and immunoblotting. RESULTS: In vivo hypoxic exposure was supported by the prominent intracellular fibroblast expression of hypoxia-inducible factor 1alpha in conduction tissue from 2 fetuses in whom CHB led to death. The possibility that hypoxia was sustained was suggested by significantly elevated erythropoietin levels in cord blood from CHB-affected, as compared with unaffected, anti-SSA/Ro-exposed neonates. In vitro exposure of cardiac fibroblasts to hypoxia resulted in transdifferentiation to myofibroblasts (a scarring phenotype), as demonstrated on immunoblots and immunofluorescence by increased expression of smooth muscle actin (SMA), an effect not seen in lung fibroblasts. Hypoxia-exposed cardiac fibroblasts expressed adrenomedullin at 4-fold increased levels, as determined by Affymetrix array, quantitative PCR, and immunofluorescence, thus focusing attention on cAMP as a modulator of fibrosis. MDL12,330A, an adenylate cyclase inhibitor that lowers the levels of cAMP, increased expression of fibrosis-related proteins (mammalian target of rapamycin, SMA, plasminogen activator inhibitor type 1, and type I collagen), while the cAMP activator forskolin attenuated transforming growth factor beta-elicited fibrosing end points in the cardiac fibroblasts. CONCLUSION: These findings provide evidence that hypoxia may amplify the injurious effects of anti-SSA/Ro antibodies. Modulation of cAMP may be a key component in the scarring phenotype. Further assessment of the susceptibility of cardiac fibroblasts to cAMP modulation offers a new research direction in CHB