Outcomes of acute leukemia patients transplanted with naive T cell–depleted stem cell grafts

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Abstract

BACKGROUND. Graft-versus-host disease (GVHD) is a major cause of morbidity and mortality following allogeneic hematopoietic stem cell transplantation (HCT). In mice, naive T cells (T_N) cause more severe GVHD than memory T cells (T_M). We hypothesized that selective depletion of T_N from human allogeneic peripheral blood stem cell (PBSC) grafts would reduce GVHD and provide sufficient numbers of hematopoietic stem cells and T_M to permit hematopoietic engraftment and the transfer of pathogen-specific T cells from donor to recipient, respectively.

METHODS. In a single-arm clinical trial, we transplanted 35 patients with high-risk leukemia with T_N-depleted PBSC grafts following conditioning with total body irradiation, thiotepa, and fludarabine. GVHD prophylactic management was with tacrolimus immunosuppression alone. Subjects received CD34-selected PBSCs and a defined dose of T_M purged of CD45RA⁺ T_N. Primary and secondary objectives included engraftment, acute and chronic GVHD, and immune reconstitution.

RESULTS. All recipients of T_N-depleted PBSCs engrafted. The incidence of acute GVHD was not reduced; however, GVHD in these patients was universally corticosteroid responsive. Chronic GVHD was remarkably infrequent (9%; median follow-up 932 days) compared with historical rates of approximately 50% with T cell–replete grafts. T_M in the graft resulted in rapid T cell recovery and transfer of protective virus-specific immunity. Excessive rates of infection or relapse did not occur and overall survival was 78% at 2 years.

CONCLUSION. Depletion of T_N from stem cell allografts reduces the incidence of chronic GVHD, while preserving the transfer of functional T cell memory.

TRIAL REGISTRATION. ClinicalTrials.gov (NCT 00914940).

FUNDING. NIH, Burroughs Wellcome Fund, Leukemia and Lymphoma Society, Damon Runyon Cancer Research Foundation, and Richard Lumsden Foundation.

Authors

Marie Bleakley, Shelly Heimfeld, Keith R. Loeb, Lori A. Jones, Colette Chaney, Stuart Seropian, Ted A. Gooley, Franziska Sommermeyer, Stanley R. Riddell, Warren D. Shlomchik

Anacetrapib lowers LDL by increasing ApoB clearance in mildly hypercholesterolemic subjects

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Abstract

BACKGROUND. Individuals treated with the cholesteryl ester transfer protein (CETP) inhibitor anacetrapib exhibit a reduction in both LDL cholesterol and apolipoprotein B (ApoB) in response to monotherapy or combination therapy with a statin. It is not clear how anacetrapib exerts these effects; therefore, the goal of this study was to determine the kinetic mechanism responsible for the reduction in LDL and ApoB in response to anacetrapib.

METHODS. We performed a trial of the effects of anacetrapib on ApoB kinetics. Mildly hypercholesterolemic subjects were randomized to background treatment of either placebo (n = 10) or 20 mg atorvastatin (ATV) (n = 29) for 4 weeks. All subjects then added 100 mg anacetrapib to background treatment for 8 weeks. Following each study period, subjects underwent a metabolic study to determine the LDL-ApoB-100 and proprotein convertase subtilisin/kexin type 9 (PCSK9) production rate (PR) and fractional catabolic rate (FCR).

RESULTS. Anacetrapib markedly reduced the LDL-ApoB-100 pool size (PS) in both the placebo and ATV groups. These changes in PS resulted from substantial increases in LDL-ApoB-100 FCRs in both groups. Anacetrapib had no effect on LDL-ApoB-100 PRs in either treatment group. Moreover, there were no changes in the PCSK9 PS, FCR, or PR in either group. Anacetrapib treatment was associated with considerable increases in the LDL triglyceride/cholesterol ratio and LDL size by NMR.

CONCLUSION. These data indicate that anacetrapib, given alone or in combination with a statin, reduces LDL-ApoB-100 levels by increasing the rate of ApoB-100 fractional clearance.

TRIAL REGISTRATION. ClinicalTrials.gov NCT00990808.

FUNDING. Merck & Co. Inc., Kenilworth, New Jersey, USA. Additional support for instrumentation was obtained from the National Center for Advancing Translational Sciences (UL1TR000003 and UL1TR000040).

Authors

John S. Millar, Gissette Reyes-Soffer, Patricia Jumes, Richard L. Dunbar, Emil M. deGoma, Amanda L. Baer, Wahida Karmally, Daniel S. Donovan, Hashmi Rafeek, Laura Pollan, Junichiro Tohyama, Amy O. Johnson-Levonas, John A. Wagner, Stephen Holleran, Joseph Obunike, Yang Liu, Rajasekhar Ramakrishnan, Michael E. Lassman, David E. Gutstein, Henry N. Ginsberg, Daniel J. Rader

Genomic imbalances in pediatric patients with chronic kidney disease

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Abstract

BACKGROUND. There is frequent uncertainty in the identification of specific etiologies of chronic kidney disease (CKD) in children. Recent studies indicate that chromosomal microarrays can identify rare genomic imbalances that can clarify the etiology of neurodevelopmental and cardiac disorders in children; however, the contribution of unsuspected genomic imbalance to the incidence of pediatric CKD is unknown.

METHODS. We performed chromosomal microarrays to detect genomic imbalances in children enrolled in the Chronic Kidney Disease in Children (CKiD) prospective cohort study, a longitudinal prospective multiethnic observational study of North American children with mild to moderate CKD. Patients with clinically detectable syndromic disease were excluded from evaluation. We compared 419 unrelated children enrolled in CKiD to multiethnic cohorts of 21,575 children and adults that had undergone microarray genotyping for studies unrelated to CKD.

RESULTS. We identified diagnostic copy number disorders in 31 children with CKD (7.4% of the cohort). We detected 10 known pathogenic genomic disorders, including the 17q12 deletion HNF1 homeobox B (HNF1B) and triple X syndromes in 19 of 419 unrelated CKiD cases as compared with 98 of 21,575 control individuals (OR 10.8, P = 6.1 × 10^–20). In an additional 12 CKiD cases, we identified 12 likely pathogenic genomic imbalances that would be considered reportable in a clinical setting. These genomic imbalances were evenly distributed among patients diagnosed with congenital and noncongenital forms of CKD. In the vast majority of these cases, the genomic lesion was unsuspected based on the clinical assessment and either reclassified the disease or provided information that might have triggered additional clinical care, such as evaluation for metabolic or neuropsychiatric disease.

CONCLUSION. A substantial proportion of children with CKD have an unsuspected genomic imbalance, suggesting genomic disorders as a risk factor for common forms of pediatric nephropathy. Detection of pathogenic imbalances has practical implications for personalized diagnosis and health monitoring in this population.

TRIAL REGISTRATION. ClinicalTrials.gov NCT00327860.

FUNDING. This work was supported by the NIH, the National Institutes of Diabetes and Digestive and Kidney Diseases (NIDDK), the National Institute of Child Health and Human Development, and the National Heart, Lung, and Blood Institute.

Authors

Miguel Verbitsky, Simone Sanna-Cherchi, David A. Fasel, Brynn Levy, Krzysztof Kiryluk, Matthias Wuttke, Alison G. Abraham, Frederick Kaskel, Anna Köttgen, Bradley A. Warady, Susan L. Furth, Craig S. Wong, Ali G. Gharavi

Quantification of mutant huntingtin protein in cerebrospinal fluid from Huntington’s disease patients

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Abstract

BACKGROUND: Quantification of disease-associated proteins in the cerebrospinal fluid (CSF) has been critical for the study and treatment of several neurodegenerative disorders; however, mutant huntingtin protein (mHTT), the cause of Huntington’s disease (HD), is at very low levels in CSF and, to our knowledge, has never been measured previously.

METHODS: We developed an ultrasensitive single-molecule counting (SMC) mHTT immunoassay that was used to quantify mHTT levels in CSF samples from individuals bearing the HD mutation and from control individuals in 2 independent cohorts.

RESULTS: This SMC mHTT immunoassay demonstrated high specificity for mHTT, high sensitivity with a femtomolar detection threshold, and a broad dynamic range. Analysis of the CSF samples showed that mHTT was undetectable in CSF from all controls but quantifiable in nearly all mutation carriers. The mHTT concentration in CSF was approximately 3-fold higher in patients with manifest HD than in premanifest mutation carriers. Moreover, mHTT levels increased as the disease progressed and were associated with 5-year onset probability. The mHTT concentration independently predicted cognitive and motor dysfunction. Furthermore, the level of mHTT was associated with the concentrations of tau and neurofilament light chain in the CSF, suggesting a neuronal origin for the detected mHTT.

CONCLUSIONS: We have demonstrated that mHTT can be quantified in CSF from HD patients using the described SMC mHTT immunoassay. Moreover, the level of mHTT detected is associated with proximity to disease onset and diminished cognitive and motor function. The ability to quantify CSF mHTT will facilitate the study of HD, and mHTT quantification could potentially serve as a biomarker for the development and testing of experimental mHTT-lowering therapies for HD.

TRIAL REGISTRATION: Not applicable.

FUNDING: CHDI Foundation Inc.; Medical Research Council (MRC) UK; National Institutes for Health Research (NIHR); Rosetrees Trust; Swedish Research Council; and Knut and Alice Wallenberg Foundation.

Authors

Edward J. Wild, Roberto Boggio, Douglas Langbehn, Nicola Robertson, Salman Haider, James R.C. Miller, Henrik Zetterberg, Blair R. Leavitt, Rainer Kuhn, Sarah J. Tabrizi, Douglas Macdonald, Andreas Weiss

Biomarkers on patient T cells diagnose active tuberculosis and monitor treatment response

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Abstract

BACKGROUND. The identification and treatment of individuals with tuberculosis (TB) is a global public health priority. Accurate diagnosis of pulmonary active TB (ATB) disease remains challenging and relies on extensive medical evaluation and detection of Mycobacterium tuberculosis (Mtb) in the patient’s sputum. Further, the response to treatment is monitored by sputum culture conversion, which takes several weeks for results. Here, we sought to identify blood-based host biomarkers associated with ATB and hypothesized that immune activation markers on Mtb-specific CD4⁺ T cells would be associated with Mtb load in vivo and could thus provide a gauge of Mtb infection.

METHODS. Using polychromatic flow cytometry, we evaluated the expression of immune activation markers on Mtb-specific CD4⁺ T cells from individuals with asymptomatic latent Mtb infection (LTBI) and ATB as well as from ATB patients undergoing anti-TB treatment.

RESULTS. Frequencies of Mtb-specific IFN-γ⁺CD4⁺ T cells that expressed immune activation markers CD38 and HLA-DR as well as intracellular proliferation marker Ki-67 were substantially higher in subjects with ATB compared with those with LTBI. These markers accurately classified ATB and LTBI status, with cutoff values of 18%, 60%, and 5% for CD38⁺IFN-γ⁺, HLA-DR⁺IFN-γ⁺, and Ki-67⁺IFN-γ⁺, respectively, with 100% specificity and greater than 96% sensitivity. These markers also distinguished individuals with untreated ATB from those who had successfully completed anti-TB treatment and correlated with decreasing mycobacterial loads during treatment.

CONCLUSION. We have identified host blood-based biomarkers on Mtb-specific CD4⁺ T cells that discriminate between ATB and LTBI and provide a set of tools for monitoring treatment response and cure.

TRIAL REGISTRATION. Registration is not required for observational studies.

FUNDING. This study was funded by Emory University, the NIH, and the Yerkes National Primate Center.

Authors

Toidi Adekambi, Chris C. Ibegbu, Stephanie Cagle, Ameeta S. Kalokhe, Yun F. Wang, Yijuan Hu, Cheryl L. Day, Susan M. Ray, Jyothi Rengarajan

Longitudinal study of living kidney donor glomerular dynamics after nephrectomy

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Abstract

BACKGROUND. Over 5,000 living kidney donor nephrectomies are performed annually in the US. While the physiological changes that occur early after nephrectomy are well documented, less is known about the long-term glomerular dynamics in living donors.

METHODS. We enrolled 21 adult living kidney donors to undergo detailed long-term clinical, physiological, and radiological evaluation pre-, early post- (median, 0.8 years), and late post- (median, 6.3 years) donation. A morphometric analysis of glomeruli obtained during nephrectomy was performed in 19 subjects.

RESULTS. Donors showed parallel increases in single-kidney renal plasma flow (RPF), renocortical volume, and glomerular filtration rate (GFR) early after the procedure, and these changes were sustained through to the late post-donation period. We used mathematical modeling to estimate the glomerular ultrafiltration coefficient (K_f), which also increased early and then remained constant through the late post-donation study. Assuming that the filtration surface area (and hence, K_f) increased in proportion to renocortical volume after donation, we calculated that the 40% elevation in the single-kidney GFR observed after donation could be attributed exclusively to an increase in the K_f. The prevalence of hypertension in donors increased from 14% in the early post-donation period to 57% in the late post-donation period. No subjects exhibited elevated levels of albuminuria.

CONCLUSIONS. Adaptive hyperfiltration after donor nephrectomy is attributable to hyperperfusion and hypertrophy of the remaining glomeruli. Our findings point away from the development of glomerular hypertension following kidney donation.

TRIAL REGISTRATION. Not applicable.

FUNDING. NIH (R01DK064697 and K23DK087937); Astellas Pharma US; the John M. Sobrato Foundation; the Satellite Extramural Grant Foundation; and the American Society of Nephrology.

Authors

Colin R. Lenihan, Stephan Busque, Geraldine Derby, Kristina Blouch, Bryan D. Myers, Jane C. Tan

Safety and tolerability of intracerebroventricular PDGF-BB in Parkinson’s disease patients

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Abstract

BACKGROUND. Recombinant human PDGF-BB (rhPDGF-BB) reduces Parkinsonian symptoms and increases dopamine transporter (DAT) binding in several animal models of Parkinson’s disease (PD). Effects of rhPDGF-BB are the result of proliferation of ventricular wall progenitor cells and reversed by blocking mitosis. Based on these restorative effects, we assessed the safety and tolerability of intracerebroventricular (i.c.v.) rhPDGF-BB administration in individuals with PD.

METHODS. We conducted a double-blind, randomized, placebo-controlled phase I/IIa study at two clinical centers in Sweden. Twelve patients with moderate PD received rhPDGF-BB via an implanted drug infusion pump and an investigational i.c.v. catheter. Patients were assigned to a dose cohort (0.2, 1.5, or 5 μg rhPDGF-BB per day) and then randomized to active treatment or placebo (3:1) for a 12-day treatment period. The primary objective was to assess safety and tolerability of i.c.v.-delivered rhPDGF-BB. Secondary outcome assessments included several clinical rating scales and changes in DAT binding. The follow-up period was 85 days.

RESULTS. All patients completed the study. There were no unresolved adverse events. Serious adverse events occurred in three patients; however, these were unrelated to rhPDGF-BB administration. Secondary outcome parameters did not show dose-dependent changes in clinical rating scales, but there was a positive effect on DAT binding in the right putamen.

CONCLUSION. At all doses tested, i.c.v. administration of rhPDGF-BB was well tolerated. Results support further clinical development of rhPDGF-BB for patients with PD.

TRIAL REGISTRATION. Clinical Trials.gov NCT00866502.

FUNDING. Newron Sweden AB (former NeuroNova AB) and Swedish Governmental Agency for Innovation Systems (VINNOVA).

Authors

Gesine Paul, Olof Zachrisson, Andrea Varrone, Per Almqvist, Markus Jerling, Göran Lind, Stig Rehncrona, Bengt Linderoth, Hjalmar Bjartmarz, Lisa L. Shafer, Robert Coffey, Mikael Svensson, Katarina Jansson Mercer, Anton Forsberg, Christer Halldin, Per Svenningsson, Håkan Widner, Jonas Frisén, Sven Pålhagen, Anders Haegerstrand

β Cell death and dysfunction during type 1 diabetes development in at-risk individuals

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Abstract

Role of the funding source: Funding from the NIH was used for support of the participating clinical centers and the coordinating center. The funding source did not participate in the collection or the analysis of the data.

BACKGROUND. The β cell killing that characterizes type 1 diabetes (T1D) is thought to begin years before patients present clinically with metabolic decompensation; however, this primary pathologic process of the disease has not been measured.

METHODS. Here, we measured β cell death with an assay that detects β cell–derived unmethylated insulin (INS) DNA. Using this assay, we performed an observational study of 50 participants from 2 cohorts at risk for developing T1D from the TrialNet Pathway to Prevention study and of 4 subjects who received islet autotransplants.

RESULTS. In at-risk subjects, those who progressed to T1D had average levels of unmethylated INS DNA that were elevated modestly compared with those of healthy control subjects. In at-risk individuals that progressed to T1D, the observed increases in unmethylated INS DNA were associated with decreases in insulin secretion, indicating that the changes in unmethylated INS DNA are indicative of β cell killing. Subjects at high risk for T1D had levels of unmethylated INS DNA that were higher than those of healthy controls and higher than the levels of unmethylated INS DNA in the at-risk progressor and at-risk nonprogressor groups followed for 4 years. Evaluation of insulin secretory kinetics also distinguished high-risk subjects who progressed to overt disease from those who did not.

CONCLUSION. We conclude that a blood test that measures unmethylated INS DNA serves as a marker of active β cell killing as the result of T1D-associated autoimmunity. Together, the data support the concept that β cell killing occurs sporadically during the years prior to diagnosis of T1D and is more intense in the peridiagnosis period.

TRIAL REGISTRATION. Clinical Trials.gov NCT00097292.

FUNDING. Funding was from the NIH, the Juvenile Diabetes Research Foundation, and the American Diabetes Association.

Authors

Kevan C. Herold, Sahar Usmani-Brown, Tara Ghazi, Jasmin Lebastchi, Craig A. Beam, Melena D. Bellin, Michel Ledizet, Jay M. Sosenko, Jeffrey P. Krischer, Jerry P. Palmer

Evaluation of noncytotoxic DNMT1-depleting therapy in patients with myelodysplastic syndromes

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Abstract

BACKGROUND. Mutational inactivation in cancer of key apoptotic pathway components, such as TP53/p53, undermines cytotoxic therapies that aim to increase apoptosis. Accordingly, TP53 mutations are reproducibly associated with poor treatment outcomes. Moreover, cytotoxic treatments destroy normal stem cells with intact p53 systems, a problem especially for myeloid neoplasms, as these cells reverse the low blood counts that cause morbidity and death. Preclinical studies suggest that noncytotoxic concentrations of the DNA methyltransferase 1 (DNMT1) inhibitor decitabine produce p53-independent cell-cycle exits by reversing aberrant epigenetic repression of proliferation-terminating (MYC-antagonizing) differentiation genes in cancer cells.

METHODS. In this clinical trial, patients with myelodysplastic syndrome (n = 25) received reduced decitabine dosages (0.1–0.2 mg/kg/day compared with the FDA-approved 20–45 mg/m²/day dosage, a 75%–90% reduction) to avoid cytotoxicity. These well-tolerated doses were frequently administered 1–3 days per week, instead of pulse cycled for 3 to 5 days over a 4- to 6-week period, to increase the probability that cancer S-phase entries would coincide with drug exposure, which is required for S-phase–dependent DNMT1 depletion.

RESULTS. The median subject age was 73 years (range, 46–85 years), 9 subjects had relapsed disease or were refractory to 5-azacytidine and/or lenalidomide, and 3 had received intensive chemoradiation to treat other cancers. Adverse events were related to neutropenia present at baseline: neutropenic fever (13 of 25 subjects) and septic death (1 of 25 subjects). Blood count improvements meeting the International Working Group criteria for response occurred in 11 of 25 (44%) subjects and were highly durable. Treatment-induced freedom from transfusion lasted a median of 1,025 days (range, 186–1,152 days; 3 ongoing), and 20% of subjects were treated for more than 3 years. Mutations and/or deletions of key apoptosis genes were frequent (present in 55% of responders and in 36% of nonresponders). Noncytotoxic DNMT1 depletion was confirmed by serial BM γ-H2AX (DNA repair/damage marker) and DNMT1 analyses. MYC master oncoprotein levels were markedly decreased.

CONCLUSION. Decitabine regimens can be redesigned to minimize cytotoxicity and increase exposure time for DNMT1 depletion, to safely and effectively circumvent mutational apoptotic defects.

TRIAL REGISTRATION. Clinicaltrials.gov NCT01165996.

FUNDING. NIH (R01CA138858, CA043703); Department of Defense (PR081404); Clinical and Translational Science Award (CTSA) (UL1RR024989); and the Leukemia and Lymphoma Society (Translational Research Program).

Authors

Yogen Saunthararajah, Mikkael Sekeres, Anjali Advani, Reda Mahfouz, Lisa Durkin, Tomas Radivoyevitch, Ricki Englehaupt, Joy Juersivich, Kathleen Cooper, Holleh Husseinzadeh, Bartlomiej Przychodzen, Matthew Rump, Sean Hobson, Marc Earl, Ronald Sobecks, Robert Dean, Frederic Reu, Ramon Tiu, Betty Hamilton, Edward Copelan, Alan Lichtin, Eric Hsi, Matt Kalaycio, Jaroslaw Maciejewski

Metabolically normal obese people are protected from adverse effects following weight gain

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Abstract

BACKGROUND. Obesity is associated with insulin resistance and increased intrahepatic triglyceride (IHTG) content, both of which are key risk factors for diabetes and cardiovascular disease. However, a subset of obese people does not develop these metabolic complications. Here, we tested the hypothesis that people defined by IHTG content and insulin sensitivity as “metabolically normal obese” (MNO), but not those defined as “metabolically abnormal obese” (MAO), are protected from the adverse metabolic effects of weight gain.

METHODS. Body composition, multiorgan insulin sensitivity, VLDL apolipoprotein B100 (apoB100) kinetics, and global transcriptional profile in adipose tissue were evaluated before and after moderate (~6%) weight gain in MNO (n = 12) and MAO (n = 8) subjects with a mean BMI of 36 ± 4 kg/m² who were matched for BMI and fat mass.

RESULTS. Although the increase in body weight and fat mass was the same in both groups, hepatic, skeletal muscle, and adipose tissue insulin sensitivity deteriorated, and VLDL apoB100 concentrations and secretion rates increased in MAO, but not MNO, subjects. Moreover, biological pathways and genes associated with adipose tissue lipogenesis increased in MNO, but not MAO, subjects.

CONCLUSIONS. These data demonstrate that MNO people are resistant, whereas MAO people are predisposed, to the adverse metabolic effects of moderate weight gain and that increased adipose tissue capacity for lipogenesis might help protect MNO people from weight gain–induced metabolic dysfunction.

TRIAL REGISTRATION. ClinicalTrials.gov NCT01184170.

FUNDING. This work was supported by NIH grants UL1 RR024992 (Clinical Translational Science Award), DK 56341 (Nutrition and Obesity Research Center), DK 37948 and DK 20579 (Diabetes Center Grant), and UL1 TR000450 (KL2 Award); a Central Society for Clinical and Translational Research Early Career Development Award; and by grants from the Longer Life Foundation and the Kilo Foundation.

Authors

Elisa Fabbrini, Jun Yoshino, Mihoko Yoshino, Faidon Magkos, Courtney Tiemann Luecking, Dmitri Samovski, Gemma Fraterrigo, Adewole L. Okunade, Bruce W. Patterson, Samuel Klein