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1.
Nat Commun ; 15(1): 216, 2024 Jan 03.
Article in English | MEDLINE | ID: mdl-38172101

ABSTRACT

Post-acute sequelae of SARS-CoV-2 (PASC) is a significant public health concern. We describe Patient Reported Outcomes (PROs) on 590 participants prospectively assessed from hospital admission for COVID-19 through one year after discharge. Modeling identified 4 PRO clusters based on reported deficits (minimal, physical, mental/cognitive, and multidomain), supporting heterogenous clinical presentations in PASC, with sub-phenotypes associated with female sex and distinctive comorbidities. During the acute phase of disease, a higher respiratory SARS-CoV-2 viral burden and lower Receptor Binding Domain and Spike antibody titers were associated with both the physical predominant and the multidomain deficit clusters. A lower frequency of circulating B lymphocytes by mass cytometry (CyTOF) was observed in the multidomain deficit cluster. Circulating fibroblast growth factor 21 (FGF21) was significantly elevated in the mental/cognitive predominant and the multidomain clusters. Future efforts to link PASC to acute anti-viral host responses may help to better target treatment and prevention of PASC.


Subject(s)
Body Fluids , COVID-19 , Female , Humans , SARS-CoV-2 , COVID-19/complications , B-Lymphocytes , Disease Progression , Phenotype
2.
N Engl J Med ; 363(3): 221-32, 2010 Jul 15.
Article in English | MEDLINE | ID: mdl-20647199

ABSTRACT

BACKGROUND: Cyclophosphamide and glucocorticoids have been the cornerstone of remission-induction therapy for severe antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis for 40 years. Uncontrolled studies suggest that rituximab is effective and may be safer than a cyclophosphamide-based regimen. METHODS: We conducted a multicenter, randomized, double-blind, double-dummy, noninferiority trial of rituximab (375 mg per square meter of body-surface area per week for 4 weeks) as compared with cyclophosphamide (2 mg per kilogram of body weight per day) for remission induction. Glucocorticoids were tapered off; the primary end point was remission of disease without the use of prednisone at 6 months. RESULTS: Nine centers enrolled 197 ANCA-positive patients with either Wegener's granulomatosis or microscopic polyangiitis. Baseline disease activity, organ involvement, and the proportion of patients with relapsing disease were similar in the two treatment groups. Sixty-three patients in the rituximab group (64%) reached the primary end point, as compared with 52 patients in the control group (53%), a result that met the criterion for noninferiority (P<0.001). The rituximab-based regimen was more efficacious than the cyclophosphamide-based regimen for inducing remission of relapsing disease; 34 of 51 patients in the rituximab group (67%) as compared with 21 of 50 patients in the control group (42%) reached the primary end point (P=0.01). Rituximab was also as effective as cyclophosphamide in the treatment of patients with major renal disease or alveolar hemorrhage. There were no significant differences between the treatment groups with respect to rates of adverse events. CONCLUSIONS: Rituximab therapy was not inferior to daily cyclophosphamide treatment for induction of remission in severe ANCA-associated vasculitis and may be superior in relapsing disease. (Funded by the National Institutes of Allergy and Infectious Diseases, Genentech, and Biogen; ClinicalTrials.gov number, NCT00104299.)


Subject(s)
Antibodies, Monoclonal/therapeutic use , Cyclophosphamide/therapeutic use , Granulomatosis with Polyangiitis/drug therapy , Immunosuppressive Agents/therapeutic use , Microscopic Polyangiitis/drug therapy , Administration, Oral , Aged , Antibodies, Antineutrophil Cytoplasmic/blood , Antibodies, Monoclonal/adverse effects , Antibodies, Monoclonal, Murine-Derived , B-Lymphocytes/drug effects , Cyclophosphamide/adverse effects , Double-Blind Method , Drug Therapy, Combination , Female , Glucocorticoids/adverse effects , Glucocorticoids/therapeutic use , Humans , Immunosuppressive Agents/adverse effects , Intention to Treat Analysis , Male , Methylprednisolone/therapeutic use , Middle Aged , Neoplasms/epidemiology , Prednisone/therapeutic use , Quality of Life , Remission Induction , Rituximab
3.
J Immunol ; 187(2): 1039-46, 2011 Jul 15.
Article in English | MEDLINE | ID: mdl-21653833

ABSTRACT

Multiple sclerosis (MS) is an autoimmune disease characterized by infiltration of pathogenic immune cells in the CNS resulting in destruction of the myelin sheath and surrounding axons. We and others have previously measured the frequency of human myelin-reactive T cells in peripheral blood. Using T cell cloning techniques, a modest increase in the frequency of myelin-reactive T cells in patients as compared with control subjects was observed. In this study, we investigated whether myelin oligodendrocyte glycoprotein (MOG)-specific T cells could be detected and their frequency was measured using DRB1*0401/MOG(97-109(107E-S)) tetramers in MS subjects and healthy controls expressing HLA class II DRB1*0401. We defined the optimal culture conditions for expansion of MOG-reactive T cells upon MOG peptide stimulation of PMBCs. MOG(97-109)-reactive CD4(+) T cells, isolated with DRB1*0401/MOG(97-109) tetramers, and after a short-term culture of PMBCs with MOG(97-109) peptides, were detected more frequently from patients with MS as compared with healthy controls. T cell clones from single cell cloning of DRB1*0401/MOG(97-109(107E-S)) tetramer(+) cells confirmed that these T cell clones were responsive to both the native and the substituted MOG peptide. These data indicate that autoantigen-specific T cells can be detected and enumerated from the blood of subjects using class II tetramers, and the frequency of MOG(97-109)-reactive T cells is greater in patients with MS as compared with healthy controls.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD4-Positive T-Lymphocytes/metabolism , HLA-DR Antigens/metabolism , Multiple Sclerosis/immunology , Multiple Sclerosis/pathology , Myelin-Associated Glycoprotein/metabolism , Peptide Fragments/metabolism , Adult , Aged , Amino Acid Substitution/genetics , Amino Acid Substitution/immunology , CD4 Lymphocyte Count , CD4-Positive T-Lymphocytes/pathology , Cell Communication/genetics , Cell Communication/immunology , Cell Line, Transformed , Cells, Cultured , Epitopes, T-Lymphocyte/biosynthesis , Epitopes, T-Lymphocyte/genetics , Female , Gene Frequency/immunology , HLA-DR Antigens/genetics , HLA-DRB1 Chains , Humans , Immunophenotyping , Male , Middle Aged , Multiple Sclerosis/genetics , Myelin-Oligodendrocyte Glycoprotein , Protein Binding/genetics , Protein Binding/immunology , Protein Multimerization/genetics , Protein Multimerization/immunology
4.
Clin Pharmacol Ther ; 112(2): 224-232, 2022 08.
Article in English | MEDLINE | ID: mdl-34551122

ABSTRACT

Clinicians and patients often try a treatment for an initial period to inform longer-term therapeutic decisions. A more rigorous approach involves N-of-1 trials. In these single-patient crossover trials, typically conducted in patients with chronic conditions, individual patients are given candidate treatments in a double-blinded, random sequence of alternating periods to determine the most effective treatment for that patient. However, to date, these trials are rarely done outside of research settings and have not been integrated into general care where they could offer substantial benefit. Designating this classical, N-of-1 trial design as type 1, there also are new and evolving uses of N-of-1 trials that we designate as type 2. In these, rather than focusing on optimizing treatment for chronic diseases when multiple approved choices are available, as is typical of type 1, a type 2 N-of-1 trial tests treatments designed specifically for a patient with a rare disease, to facilitate personalized medicine. While the aims differ, both types face the challenge of collecting individual-patient evidence using standard, trusted, widely accepted methods. To fulfill their potential for producing both clinical and research benefits, and to be available for wide use, N-of-1 trials will have to fit into the current healthcare ecosystem. This will require generalizable and accepted processes, platforms, methods, and standards. This also will require sustainable value-based arrangements among key stakeholders. In this article, we review opportunities, stakeholders, issues, and possible approaches that could support general use of N-of-1 trials and deliver benefit to patients and the healthcare enterprise. To assess and expand the benefits of N-of-1 trials, we propose multistakeholder meetings, workshops, and the generation of methods, standards, and platforms that would support wider availability and the value of N-of-1 trials.


Subject(s)
Delivery of Health Care , Ecosystem , Humans , Treatment Outcome
5.
J Clin Invest ; 118(8): 2684-6, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18654643

ABSTRACT

Long-term allograft survival requires lifelong immunosuppression, which comes with serious side effects. Inducing immune tolerance to the transplant would enable immunosuppression withdrawal and revolutionize the quality of life of transplant recipients. In this issue of the JCI, Martínez-Llordella et al. identify a profile of biomarkers that predict tolerance in liver transplant recipients (see the related article beginning on page 2845). These findings translate into a new means for prospectively selecting liver transplant patients who would benefit from immunosuppression withdrawal and ultimately may guide development of tolerogenic therapies that allow for allograft acceptance without the use of long-term immunosuppression.


Subject(s)
Immune Tolerance , Immunosuppression Therapy , Liver Transplantation/immunology , Transplantation Immunology/genetics , Transplantation Tolerance/genetics , Biomarkers/metabolism , Graft Rejection/diagnosis , Graft Rejection/genetics , Graft Rejection/immunology , Humans , Immunosuppressive Agents/administration & dosage , Models, Immunological , Patient Selection , Survival Analysis
6.
Pediatr Rheumatol Online J ; 19(1): 40, 2021 Mar 22.
Article in English | MEDLINE | ID: mdl-33752695

ABSTRACT

BACKGROUND: Pediatric patients with juvenile idiopathic arthritis (JIA) are at risk for a lower health-related quality of life compared to their healthy peers. Remote monitoring of health-related quality of life using electronic patient-reported outcomes could provide important information to treating physicians. The aim of this study was to investigate if self-assessment with the EuroQol five-dimensional 'youth' questionnaire with five levels (EQ-5D-Y-5 L) inside a mobile E-health application could identify JIA patients in need of possible treatment adjustments. METHODS: The EQ-5D-Y-5 L was completed via a mobile application (Reuma2Go) between October 2017 and January 2019. The clinical juvenile arthritis disease activity score with 71 joint count (cJADAS-71) was reported at every corresponding visit as reference for disease activity. Previously described cJADAS-71 thresholds were used to identify patients in possible need of treatment adjustments. Discriminatory power of the EQ-5D-Y-5 L was assessed by ROC-curves and diagnostic characteristics. RESULTS: Sixty-eight JIA patients completed the EQ-5D-Y-5 L questionnaire. Median cJADAS-71 indicated low disease activity overall in the studied population. ROC curves and diagnostic characteristics demonstrated that self-assessment with the EQ-5D-Y-5 L could distinguish between patients with inactive disease (or minimal disease activity) and moderate to high disease activity with good accuracy (87%), sensitivity (85%), specificity (89%) and negative predictive value (86%). CONCLUSIONS: Results demonstrate that the EQ-5D-Y-5 L was able to identify JIA patients in need of possible treatment adjustments in our studied population. Remote monitoring of health-related quality of life and patient-reported outcomes via E-health applications could provide important additional information to determine the frequency of clinical visits, assess therapeutic efficacy and guide treat-to-target strategies in pediatric patients with JIA.


Subject(s)
Arthritis, Juvenile/diagnosis , Diagnostic Self Evaluation , Mobile Applications , Monitoring, Ambulatory/methods , Quality of Life , Adolescent , Child , Female , Humans , Male , Retrospective Studies
7.
Bioinformatics ; 25(1): 48-53, 2009 Jan 01.
Article in English | MEDLINE | ID: mdl-19015138

ABSTRACT

MOTIVATION: As the use of microarrays in human studies continues to increase, stringent quality assurance is necessary to ensure accurate experimental interpretation. We present a formal approach for microarray quality assessment that is based on dimension reduction of established measures of signal and noise components of expression followed by parametric multivariate outlier testing. RESULTS: We applied our approach to several data resources. First, as a negative control, we found that the Affymetrix and Illumina contributions to MAQC data were free from outliers at a nominal outlier flagging rate of alpha=0.01. Second, we created a tunable framework for artificially corrupting intensity data from the Affymetrix Latin Square spike-in experiment to allow investigation of sensitivity and specificity of quality assurance (QA) criteria. Third, we applied the procedure to 507 Affymetrix microarray GeneChips processed with RNA from human peripheral blood samples. We show that exclusion of arrays by this approach substantially increases inferential power, or the ability to detect differential expression, in large clinical studies. AVAILABILITY: http://bioconductor.org/packages/2.3/bioc/html/arrayMvout.html and http://bioconductor.org/packages/2.3/bioc/html/affyContam.html affyContam (credentials: readonly/readonly)


Subject(s)
Gene Expression Profiling , Oligonucleotide Array Sequence Analysis/methods , Ambrosia/immunology , Clinical Trials as Topic , Gene Expression Regulation , Humans , Hypersensitivity/genetics , Hypersensitivity/immunology , Multivariate Analysis , Principal Component Analysis
8.
BMC Immunol ; 10: 52, 2009 Sep 28.
Article in English | MEDLINE | ID: mdl-19785746

ABSTRACT

BACKGROUND: Growing knowledge about cellular interactions in the immune system, including the central role of cytokine networks, has lead to new treatments using monoclonal antibodies that block specific components of the immune system. Systemic cytokine concentrations can serve as surrogate outcome parameters of these interventions to study inflammatory pathways operative in patients in vivo. This is now possible due to novel technologies such as multiplex immunoassays (MIA) that allows detection of multiple cytokines in a single sample. However, apparently trivial underappreciated processes, (sample handling and storage, interference of endogenous plasma proteins) can greatly impact the reliability and reproducibility of cytokine detection.Therefore we set out to investigate several processes that might impact cytokine profiles such as blood collecting tubes, duration of storage, and number of freeze thawing cycles. RESULTS: Since under physiological conditions cytokine concentrations normally are low or undetectable we spiked cytokines in the various plasma and serum samples. Overall recoveries ranged between 80-120%. Long time storage showed cytokines are stable for a period up to 2 years of storage at -80 degrees C. After 4 years several cytokines (IL-1alpha, IL-1beta, IL-10, IL-15 and CXCL8) degraded up to 75% or less of baseline values. Furthermore we show that only 2 out of 15 cytokines remained stable after several freeze-thawing cycles. We also demonstrate implementation of an internal control for multiplex cytokine immunoassays. CONCLUSION: All together we show parameters which are essential for measurement of cytokines in the context of clinical trials.


Subject(s)
Cytokines/metabolism , Immunoassay , Leukocytes, Mononuclear/metabolism , Blood Specimen Collection/adverse effects , Cells, Cultured , Clinical Trials as Topic , Edetic Acid/metabolism , Freezing/adverse effects , Heparin/metabolism , Humans , Immunoassay/instrumentation , Immunoassay/methods , Immunoassay/standards , Leukocytes, Mononuclear/immunology , Leukocytes, Mononuclear/pathology , Lipopolysaccharides/metabolism , Phytohemagglutinins/metabolism , Protein Stability , Reference Standards , Reproducibility of Results
9.
Clin Immunol ; 132(2): 166-73, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19443276

ABSTRACT

Anti-CD3 mAbs may prolong beta cell function up to 2 years in patients with new onset Type 1 diabetes (T1DM). A randomized open label trial of anti-CD3 mAb, Teplizumab, in T1DM was stopped after 10 subjects because of increased adverse events than in a previous trial related with higher dosing of drug. Teplizumab caused transient reduction in circulating T cells, but the recovered cells were not new thymic emigrants because T cell receptor excision circles were not increased. There was a trend for reduced loss of C-peptide over 2 years with drug treatment (p=0.1), and insulin use was lower (p<0.001). In 4 drug-treated subjects followed up to 60 months, C-peptide responses were maintained. We conclude that increased doses of Teplizumab are associated with greater adverse events without improved efficacy. The drug may marginate rather than deplete T cells. C-peptide levels may remain detectable up to 5 years after treatment.


Subject(s)
CD3 Complex/immunology , Diabetes Mellitus, Type 1/drug therapy , Insulin/metabolism , Muromonab-CD3/therapeutic use , Adolescent , Antibodies, Monoclonal, Humanized , C-Peptide/metabolism , Child , Diabetes Mellitus, Type 1/metabolism , Diabetes Mellitus, Type 1/pathology , Exanthema/chemically induced , Female , Fever/chemically induced , Follow-Up Studies , Gastrointestinal Diseases/chemically induced , Humans , Hypoglycemic Agents/metabolism , Hypoglycemic Agents/therapeutic use , Insulin/therapeutic use , Male , Muromonab-CD3/adverse effects , Nausea/chemically induced , Treatment Outcome , Vomiting/chemically induced
10.
N Engl J Med ; 355(13): 1318-30, 2006 Sep 28.
Article in English | MEDLINE | ID: mdl-17005949

ABSTRACT

BACKGROUND: Islet transplantation offers the potential to improve glycemic control in a subgroup of patients with type 1 diabetes mellitus who are disabled by refractory hypoglycemia. We conducted an international, multicenter trial to explore the feasibility and reproducibility of islet transplantation with the use of a single common protocol (the Edmonton protocol). METHODS: We enrolled 36 subjects with type 1 diabetes mellitus, who underwent islet transplantation at nine international sites. Islets were prepared from pancreases of deceased donors and were transplanted within 2 hours after purification, without culture. The primary end point was defined as insulin independence with adequate glycemic control 1 year after the final transplantation. RESULTS: Of the 36 subjects, 16 (44%) met the primary end point, 10 (28%) had partial function, and 10 (28%) had complete graft loss 1 year after the final transplantation. A total of 21 subjects (58%) attained insulin independence with good glycemic control at any point throughout the trial. Of these subjects, 16 (76%) required insulin again at 2 years; 5 of the 16 subjects who reached the primary end point (31%) remained insulin-independent at 2 years. CONCLUSIONS: Islet transplantation with the use of the Edmonton protocol can successfully restore long-term endogenous insulin production and glycemic stability in subjects with type 1 diabetes mellitus and unstable control, but insulin independence is usually not sustainable. Persistent islet function even without insulin independence provides both protection from severe hypoglycemia and improved levels of glycated hemoglobin. (ClinicalTrials.gov number, NCT00014911 [ClinicalTrials.gov].).


Subject(s)
Diabetes Mellitus, Type 1/therapy , Islets of Langerhans Transplantation/methods , Adult , Blood Glucose/metabolism , C-Peptide/blood , Diabetes Mellitus, Type 1/blood , Feasibility Studies , Follow-Up Studies , Humans , Hypoglycemic Agents/therapeutic use , Immunosuppressive Agents/adverse effects , Immunosuppressive Agents/therapeutic use , Infusions, Intravenous , Insulin/metabolism , Insulin/therapeutic use , Insulin Secretion , Islets of Langerhans Transplantation/adverse effects , Islets of Langerhans Transplantation/standards , Isoantibodies/blood , Middle Aged , Opportunistic Infections/epidemiology , Portal Vein , Reproducibility of Results , Transplantation Conditioning/standards
11.
Clin Pharmacol Ther ; 105(4): 857-866, 2019 04.
Article in English | MEDLINE | ID: mdl-30610746

ABSTRACT

Efficacy trials, designed to gain regulatory marketing approval, evaluate drugs in optimally selected patients under advantageous conditions for relatively short time periods. Effectiveness trials, designed to evaluate use in usual practice, assess treatments among more typical patients in real-world conditions with longer follow-up periods. In "efficacy-to-effectiveness (E2E) trials," if the initial efficacy trial component is positive, the trial seamlessly transitions to an effectiveness trial component to efficiently yield both types of evidence. Yet more time could be saved by simultaneously addressing efficacy and effectiveness in an "efficacy and effectiveness too (EE2) trial." Additionally, hybrids of the E2E and EE2 approaches with differing degrees of overlap of the two components could allow flexibility for specific drug development needs. In planning EE2 trials, each stakeholder's current and future needs, incentives, and perspective must be considered. Although challenging, the ultimate benefits to stakeholders, the health system, and the public should justify this effort.


Subject(s)
Clinical Trials as Topic/legislation & jurisprudence , Drug Approval/legislation & jurisprudence , Drug Development/legislation & jurisprudence , Research Design/legislation & jurisprudence , Cost-Benefit Analysis/legislation & jurisprudence , Humans , Marketing/legislation & jurisprudence , Patient Selection , Treatment Outcome
12.
BMC Genomics ; 9: 474, 2008 Oct 10.
Article in English | MEDLINE | ID: mdl-18847473

ABSTRACT

BACKGROUND: RNA isolation and purification steps greatly influence the results of gene expression profiling. There are two commercially available products for whole blood RNA collection, PAXgene and Tempus blood collection tubes, and each comes with their own RNA purification method. In both systems the blood is immediately lysed when collected into the tube and RNA stabilized using proprietary reagents. Both systems enable minimal blood handling procedures thus minimizing the risk of inducing changes in gene expression through blood handling or processing. Because the RNA purification steps could influence the total RNA pool, we examined the impact of RNA isolation, using the PAXgene or Tempus method, on gene expression profiles. RESULTS: Using microarrays as readout of RNA from stimulated whole blood we found a common set of expressed transcripts in RNA samples from either PAXgene or Tempus. However, we also found several to be uniquely expressed depending on the type of collection tube, suggesting that RNA purification methods impact results of differential gene expression profiling. Specifically, transcripts for several known PHA-inducible genes, including IFNgamma, IL13, IL2, IL3, and IL4 were found to be upregulated in stimulated vs. control samples when RNA was isolated using the ABI Tempus method, but not using the PAXgene method (p < 0.01, FDR corrected). Sequenom Quantiative Gene Expression (QGE) (SanDiego, CA) measures confirmed IL2, IL4 and IFNgamma up-regulation in Tempus purified RNA from PHA stimulated cells while only IL2 was up-regulated using PAXgene purified (p < 0.05). CONCLUSION: Here, we demonstrate that peripheral blood RNA isolation methods can critically impact differential expression results, particularly in the clinical setting where fold-change differences are typically small and there is inherent variability within biological cohorts. A modified method based upon the Tempus system was found to provide high yield, good post-hybridization array quality, low variability in expression measures and was shown to produce differential expression results consistent with the predicted immunologic effects of PHA stimulation.


Subject(s)
Blood Specimen Collection/methods , Gene Expression Profiling/methods , RNA/blood , RNA/isolation & purification , Oligonucleotide Array Sequence Analysis/methods , Phytohemagglutinins/pharmacology , Transcription, Genetic/immunology
13.
Diabetes ; 55(9): 2588-94, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16936208

ABSTRACT

Type 1 diabetes is a chronic autoimmune disease mediated by autoreactive T-cells. Several experimental therapies targeting T-cells are in clinical trials. To understand how these therapies affect T-cell responses in vivo, assays that directly measure human T-cell function are needed. In a blinded, multicenter, case-controlled study conducted by the Immune Tolerance Network, we tested responses in an immunoblot and T-cell proliferative assay to distinguish type 1 diabetic patients from healthy control subjects. Peripheral blood cells from 39 healthy control subjects selected for DR4 and 23 subjects with recently diagnosed type 1 diabetes were studied. Autoantibody responses were measured in serum samples. Positive responses in both assays were more common in peripheral blood mononuclear cells from new-onset type 1 diabetic patients compared with control subjects. The proliferative, immunoblot, and autoantibody assays had sensitivities of 58, 91, and 78% with specificities of 94, 83, and 85%, respectively. When cellular assays were combined with autoantibody measurements, the sensitivity of the measurements was 75% with 100% specificity. We conclude that cellular assays performed on peripheral blood have a high degree of accuracy in discriminating responses in subjects with type 1 diabetes from healthy control subjects. They may be useful for assessment of cellular autoimmune responses involved in type 1 diabetes.


Subject(s)
Autoimmunity/immunology , Diabetes Mellitus, Type 1/immunology , T-Lymphocytes/immunology , Adolescent , Adult , Autoantibodies/analysis , Cell Proliferation , Child , Female , Glutamate Decarboxylase/analysis , Humans , Immunoblotting , Isoenzymes/analysis , Male , Sensitivity and Specificity
15.
18.
Pediatr Clin North Am ; 57(2): 523-38, table of contents, 2010 Apr.
Article in English | MEDLINE | ID: mdl-20371050

ABSTRACT

In the clinical arena of transplantation, tolerance remains, for the most part, a concept rather than a reality. Although modern immunosuppression regimens have effectively handled acute rejection, nearly all organs except the liver commonly suffer chronic immunologic damage that impairs organ function, threatening patient and allograft survival. In addition to the imperfect control of the donor-directed immune response, there are additional costs. First, there is the burden of mortality from infection and malignancy that can be directly attributed to a crippled immune system. Second, there are insidious effects on renal function, cardiovascular profile (hypertension, hyperglycemia, and dyslipidemia), bone health, growth, psychological and neurocognitive development, and overall quality of life. It is likely that the full consequences of lifelong immunosuppression on our pediatric transplant recipients will not be fully appreciated until survival routinely extends beyond 1 or 2 decades after transplantation. Therefore, it can be argued that the holy grail of transplantation tolerance is of the utmost importance to children who undergo solid organ transplantation.


Subject(s)
Organ Transplantation , Transplantation Tolerance , Biomarkers , Child , Humans , Kidney Transplantation , Liver Transplantation , Models, Immunological , Monitoring, Immunologic , Transplantation Immunology , Transplantation Tolerance/immunology
19.
J Clin Invest ; 120(6): 1836-47, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20501946

ABSTRACT

Establishing long-term allograft acceptance without the requirement for continuous immunosuppression, a condition known as allograft tolerance, is a highly desirable therapeutic goal in solid organ transplantation. Determining which recipients would benefit from withdrawal or minimization of immunosuppression would be greatly facilitated by biomarkers predictive of tolerance. In this study, we identified the largest reported cohort to our knowledge of tolerant renal transplant recipients, as defined by stable graft function and receiving no immunosuppression for more than 1 year, and compared their gene expression profiles and peripheral blood lymphocyte subsets with those of subjects with stable graft function who are receiving immunosuppressive drugs as well as healthy controls. In addition to being associated with clinical and phenotypic parameters, renal allograft tolerance was strongly associated with a B cell signature using several assays. Tolerant subjects showed increased expression of multiple B cell differentiation genes, and a set of just 3 of these genes distinguished tolerant from nontolerant recipients in a unique test set of samples. This B cell signature was associated with upregulation of CD20 mRNA in urine sediment cells and elevated numbers of peripheral blood naive and transitional B cells in tolerant participants compared with those receiving immunosuppression. These results point to a critical role for B cells in regulating alloimmunity and provide a candidate set of genes for wider-scale screening of renal transplant recipients.


Subject(s)
B-Lymphocytes/immunology , Immune Tolerance/immunology , Kidney Transplantation/immunology , Transplantation Tolerance/genetics , Biomarkers , Gene Expression Profiling , Humans , Immunosuppression Therapy/methods , Lymphocyte Activation/immunology , Transplantation Tolerance/immunology
20.
J Clin Invest ; 120(6): 1848-61, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20501943

ABSTRACT

Identifying transplant recipients in whom immunological tolerance is established or is developing would allow an individually tailored approach to their posttransplantation management. In this study, we aimed to develop reliable and reproducible in vitro assays capable of detecting tolerance in renal transplant recipients. Several biomarkers and bioassays were screened on a training set that included 11 operationally tolerant renal transplant recipients, recipient groups following different immunosuppressive regimes, recipients undergoing chronic rejection, and healthy controls. Highly predictive assays were repeated on an independent test set that included 24 tolerant renal transplant recipients. Tolerant patients displayed an expansion of peripheral blood B and NK lymphocytes, fewer activated CD4+ T cells, a lack of donor-specific antibodies, donor-specific hyporesponsiveness of CD4+ T cells, and a high ratio of forkhead box P3 to alpha-1,2-mannosidase gene expression. Microarray analysis further revealed in tolerant recipients a bias toward differential expression of B cell-related genes and their associated molecular pathways. By combining these indices of tolerance as a cross-platform biomarker signature, we were able to identify tolerant recipients in both the training set and the test set. This study provides an immunological profile of the tolerant state that, with further validation, should inform and shape drug-weaning protocols in renal transplant recipients.


Subject(s)
Biomarkers/metabolism , Immune Tolerance/immunology , Immunosuppressive Agents/immunology , Kidney Transplantation/immunology , Humans , Immune Tolerance/genetics , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Tissue Donors
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