-
Journal of Proteome Research Mar 2018Charge deconvolution infers the mass from mass over charge (m/z) measurements in electrospray ionization mass spectra. When applied over a wide input m/z or broad target...
Charge deconvolution infers the mass from mass over charge (m/z) measurements in electrospray ionization mass spectra. When applied over a wide input m/z or broad target mass range, charge-deconvolution algorithms can produce artifacts, such as false masses at one-half or one-third of the correct mass. Indeed, a maximum entropy term in the objective function of MaxEnt, the most commonly used charge deconvolution algorithm, favors a deconvolved spectrum with many peaks over one with fewer peaks. Here we describe a new "parsimonious" charge deconvolution algorithm that produces fewer artifacts. The algorithm is especially well-suited to high-resolution native mass spectrometry of intact glycoproteins and protein complexes. Deconvolution of native mass spectra poses special challenges due to salt and small molecule adducts, multimers, wide mass ranges, and fewer and lower charge states. We demonstrate the performance of the new deconvolution algorithm on a range of samples. On the heavily glycosylated plasma properdin glycoprotein, the new algorithm could deconvolve monomer and dimer simultaneously and, when focused on the m/z range of the monomer, gave accurate and interpretable masses for glycoforms that had previously been analyzed manually using m/z peaks rather than deconvolved masses. On therapeutic antibodies, the new algorithm facilitated the analysis of extensions, truncations, and Fab glycosylation. The algorithm facilitates the use of native mass spectrometry for the qualitative and quantitative analysis of protein and protein assemblies.
Topics: Algorithms; Antibodies, Monoclonal, Humanized; Cetuximab; Daclizumab; Entropy; Glycoproteins; Glycosylation; Humans; Immunoglobulin G; Infliximab; Peptide Fragments; Peptide Mapping; Properdin; Proteolysis; Solutions; Spectrometry, Mass, Electrospray Ionization; Static Electricity; Trypsin
PubMed: 29376659
DOI: 10.1021/acs.jproteome.7b00839 -
Biomedicines Mar 2019Daclizumab (DAC) is a humanized, monoclonal antibody that blocks CD25, a critical element of the high-affinity interleukin-2 receptor (IL-2R). DAC HYP blockade of CD25... (Review)
Review
Daclizumab: Mechanisms of Action, Therapeutic Efficacy, Adverse Events and Its Uncovering the Potential Role of Innate Immune System Recruitment as a Treatment Strategy for Relapsing Multiple Sclerosis.
Daclizumab (DAC) is a humanized, monoclonal antibody that blocks CD25, a critical element of the high-affinity interleukin-2 receptor (IL-2R). DAC HYP blockade of CD25 inhibits effector T cell activation, regulatory T cell expansion and survival, and activation-induced T-cell apoptosis. Because CD25 blockade reduces IL-2 consumption by effector T cells, it increases IL-2 bioavailability allowing for greater interaction with the intermediate-affinity IL-2R, and therefore drives the expansion of CD56 natural killer (NK) cells. Furthermore, there appears to be a direct correlation between CD56 NK cell expansion and DAC HYP efficacy in reducing relapses and MRI evidence of disease activity in patients with RMS in phase II and phase III double-blind, placebo- and active comparator-controlled trials. Therapeutic efficacy was maintained during open-label extension studies. However, treatment was associated with an increased risk of rare adverse events, including cutaneous inflammation, autoimmune hepatitis, central nervous system Drug Reaction with Eosinophilia Systemic Symptoms (DRESS) syndrome, and autoimmune Glial Fibrillary Acidic Protein (GFAP) alpha immunoglobulin-associated encephalitis. As a result, DAC HYP was removed from clinical use in 2018. The lingering importance of DAC is that its use led to a deeper understanding of the underappreciated role of innate immunity in the potential treatment of autoimmune disease.
PubMed: 30862055
DOI: 10.3390/biomedicines7010018 -
Therapeutic Advances in Neurological... Jan 2017Daclizumab is a humanized monoclonal antibody that binds to the α subunit (CD25) of the interleukin-2 receptor and favorably modulates the immune environment in... (Review)
Review
Daclizumab is a humanized monoclonal antibody that binds to the α subunit (CD25) of the interleukin-2 receptor and favorably modulates the immune environment in multiple sclerosis (MS). Blockage of CD25, among other effects, causes expansion and enhanced function of regulatory CD56 natural killer cells, which seems to be the leading mechanism of action in MS. Phase II and III clinical trials have demonstrated that monthly subcutaneous injections of daclizumab high yield process (DAC HYP) 150 mg in patients with relapsing MS led to a significant reduction of annualized relapse rate and decreased number of contrast-enhanced lesions on brain magnetic resonance imaging. Treatment with DAC HYP had efficacy superior to treatment with weekly injections of interferon β1a. This review summarizes the development of and clinical experience with daclizumab in MS.
PubMed: 28450896
DOI: 10.1177/1756285616671887 -
Neurotherapeutics : the Journal of the... Apr 2022In the past two decades, monoclonal antibodies (mAbs) have revolutionized the treatment of multiple sclerosis (MS). However, a remarkable number of mAbs failed due to... (Review)
Review
In the past two decades, monoclonal antibodies (mAbs) have revolutionized the treatment of multiple sclerosis (MS). However, a remarkable number of mAbs failed due to negative study results were withdrawn because of unexpected serious adverse events (SAEs) or due to studies being halted for other reasons. While trials with positive outcomes are usually published in prestigious journals, negative trials are merely published as abstracts or not at all. This review summarizes MS mAbs that have either failed in phase II-III trials, have been interrupted for various reasons, or withdrawn from the market since 2015. The main conclusions that can be drawn from these 'negative' experiences are as follows. mAbs that have been proven to be safe in other autoimmune conditions, will not have the same safety profile in MS due to immunopathogenetic differences in these diseases (e.g., daclizumab). Identification of SAEs in clinical trials is difficult highlighting the importance of phase IV studies. Memory B cells are central players in MS immunopathogenesis (e.g., tabalumab). The pathophysiological mechanisms of disease progression are independent of leukocyte 'outside-in' traffic which drives relapses in MS. Therefore, therapies for progressive MS must be able to sufficiently cross the blood-brain barrier. Sufficiently long trial duration and multicomponent outcome measures are important for clinical studies in progressive MS. The success of trials on remyelination-promoting therapies mainly depends on the sufficient high dose of mAb, the optimal readout for 'proof of concept', time of treatment initiation, and appropriate selection of patients. Failed strategies are highly important to better understand assumed immunopathophysiological mechanisms and optimizing future trial designs.
Topics: Antibodies, Monoclonal; Autoimmune Diseases; Daclizumab; Humans; Multiple Sclerosis; Multiple Sclerosis, Chronic Progressive
PubMed: 35794296
DOI: 10.1007/s13311-022-01246-3 -
Neurology(R) Neuroimmunology &... Jul 2024Multiple sclerosis (MS) is considered a prototypic autoimmune disease of the CNS. It is the leading cause of chronic neurologic disability in young adults....
BACKGROUND AND OBJECTIVES
Multiple sclerosis (MS) is considered a prototypic autoimmune disease of the CNS. It is the leading cause of chronic neurologic disability in young adults. Proinflammatory B cells and autoreactive T cells both play important roles in its pathogenesis. We aimed to study alterations of regulatory T cells (Tregs), which likely also contribute to the disease, but their involvement is less clear.
METHODS
By combining multiple experimental approaches, we examined the Treg compartments in 41 patients with relapsing-remitting MS and 17 healthy donors.
RESULTS
Patients with MS showed a reduced frequency of CD4 T cells and Foxp3+ Tregs and age-dependent alterations of Treg subsets. Treg suppressive function was compromised in patients, who were treated with natalizumab, while it was unaffected in untreated and anti-CD20-treated patients. The changes in natalizumab-treated patients included increased proinflammatory cytokines and an altered transcriptome in thymus-derived (t)-Tregs, but not in peripheral (p)-Tregs.
DISCUSSION
Treg dysfunction in patients with MS might be related to an altered transcriptome of t-Tregs and a proinflammatory environment. Our findings contribute to a better understanding of Tregs and their subtypes in MS.
Topics: Humans; T-Lymphocytes, Regulatory; Adult; Female; Male; Multiple Sclerosis, Relapsing-Remitting; Natalizumab; Middle Aged; Thymus Gland; Immunologic Factors; Young Adult
PubMed: 38838284
DOI: 10.1212/NXI.0000000000200251 -
World Journal of Transplantation Mar 2021Heart transplant recipients are at higher risk of developing skin cancer than the general population due to the long-term immunosuppression treatment. Cancer has been...
BACKGROUND
Heart transplant recipients are at higher risk of developing skin cancer than the general population due to the long-term immunosuppression treatment. Cancer has been reported as one of the major causes of morbidity and mortality for patients after heart transplantation. Among different types of skin cancers, cutaneous squamous cell carcinoma (cSCC) is the most common one, which requires timely screening and better management.
AIM
To identify risk factors and predict the incidence of cSCC for heart transplant recipients.
METHODS
We retrospectively analyzed adult heart transplant recipients between 2000 and 2015 extracted from the United Network for Organ Sharing registry. The whole dataset was randomly divided into a derivation set (80%) and a validation set (20%). Uni- and multivariate Cox regression were done to identify significant risk factors associated with the development of cSCC. Receiver operating charac-teristics curves were generated and area under the curve (AUC) was calculated to assess the accuracy of the prediction model. Based on the selected risk factors, a risk scoring system was developed to stratify patients into different risk groups. A cumulative cSCC-free survival curve was generated using the Kaplan-Meier method for each group, and the log-rank test was done to compare the inter-group cSCC rates.
RESULTS
There were 23736 heart-transplant recipients during the study period, and 1827 of them have been reported with cSCC. Significant predictors of post-transplant cSCC were older age, male sex, white race, recipient and donor human leukocyte antigen (HLA) mismatch level, malignancy at listing, diagnosis with restrictive myopathy or hypertrophic myopathy, heart re-transplant, and induction therapy with OKT3 or daclizumab. The multivariate model was used to predict the 5-, 8- and 10-year incidence of cSCC and respectively provided AUC of 0.79, 0.78 and 0.77 in the derivation set and 0.80, 0.78 and 0.77 in the validation set. The risk scoring system assigned each patient with a risk score within the range of 0-11, based on which they were stratified into 4 different risk groups. The predicted and observed 5-year probability of developing cSCC match well among different risk groups. In addition, the log-rank test indicated significantly different cSCC-free survival across different groups.
CONCLUSION
A risk prediction model for cSCC among heart-transplant recipients has been generated for the first time. It offers a c-statistic of ≥ 0.77 in both derivation and validation sets.
PubMed: 33816146
DOI: 10.5500/wjt.v11.i3.54 -
Multiple Sclerosis (Houndmills,... Sep 2021In multiple sclerosis, impact of treatment on disability progression can be confounded if treatment also reduces relapses. (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
In multiple sclerosis, impact of treatment on disability progression can be confounded if treatment also reduces relapses.
OBJECTIVE
To distinguish siponimod's direct effects on disability progression from those on relapses in the EXPAND phase 3 trial.
METHODS
Three estimands, one based on principal stratum and two on hypothetical scenarios (no relapses, or equal relapses in both treatment arms), were defined to determine the extent to which siponimod's effects on 3- and 6-month confirmed disability progression were independent of on-study relapses.
RESULTS
Principal stratum analysis estimated that siponimod reduced the risk of 3- and 6-month confirmed disability progression by 14%-20% and 29%-33%, respectively, compared with placebo in non-relapsing patients. In the hypothetical scenarios, risk reductions independent of relapses were 14%-18% and 23% for 3- and 6-month confirmed disability progression, respectively.
CONCLUSION
By controlling the confounding impact of on-study relapses on confirmed disability progression, these statistical approaches provide a methodological framework to assess treatment effects on disability progression in relapsing and non-relapsing patients. The analyses support that siponimod may be useful for treating secondary progressive multiple sclerosis in patients with or without relapses.
Topics: Azetidines; Benzyl Compounds; Disease Progression; Humans; Multiple Sclerosis, Chronic Progressive; Recurrence
PubMed: 33205682
DOI: 10.1177/1352458520971819 -
Proceedings of the National Academy of... Oct 2019Interleukin-2 (IL-2) and IL-15 play pivotal roles in T cell activation, apoptosis, and survival, and are implicated in leukemias and autoimmune diseases. Their...
Interleukin-2 (IL-2) and IL-15 play pivotal roles in T cell activation, apoptosis, and survival, and are implicated in leukemias and autoimmune diseases. Their heterotrimeric receptors share their β- and γ-chains, but have distinct α-chains. Anti-IL-2Rα (daclizumab) therapy targeting cell surface-expressed receptor subunits to inhibit T cell proliferation has only brought limited success in adult T cell leukemia/lymphoma (ATL) and in multiple sclerosis. We asked whether IL-2R subunits could already preassemble and signal efficiently in the endoplasmic reticulum (ER) and the Golgi. A combination of daclizumab and anti-IL-2 efficiently blocked IL-2-induced proliferation of IL-2-dependent wild-type (WT) ATL cells but not cells transfected with IL-2, suggesting that in IL-2-producing cells signaling may already take place before receptors reach the cell surface. In the Golgi fraction isolated from IL-2-producing ATL cells, we detected by Western blot phosphorylated Jak1, Jak3, and a phosphotyrosine signal attributed to the γ-chain, which occurred at much lower levels in the Golgi of WT ATL cells. We expressed EGFP- and mCherry-tagged receptor chains in HeLa cells to study their assembly along the secretory pathway. Confocal microscopy, Förster resonance energy transfer, and imaging fluorescence cross-correlation spectroscopy analysis revealed partial colocalization and molecular association of IL-2 (and IL-15) receptor chains in the ER/Golgi, which became more complete in the plasma membrane, further confirming our hypothesis. Our results define a paradigm of intracellular autocrine signaling and may explain resistance to antagonistic antibody therapies targeting receptors at the cell surface.
Topics: Cell Line, Tumor; Cell Proliferation; Endoplasmic Reticulum; Golgi Apparatus; HeLa Cells; Humans; Interleukin-15; Interleukin-2; Interleukin-2 Receptor alpha Subunit; Janus Kinase 1; Janus Kinase 3; Receptors, Interleukin-15; Signal Transduction
PubMed: 31570576
DOI: 10.1073/pnas.1901382116 -
Therapeutic Advances in Neurological... Nov 2015Monoclonal antibody (mAb) therapies for relapsing-remitting multiple sclerosis (MS) target immune cells or other molecules involved in pathogenic pathways with... (Review)
Review
Monoclonal antibody (mAb) therapies for relapsing-remitting multiple sclerosis (MS) target immune cells or other molecules involved in pathogenic pathways with extraordinary specificity. Natalizumab and alemtuzumab are the only two currently approved mAbs for the treatment of MS, having demonstrated significant reduction in clinical and magnetic resonance imaging disease activity and disability in clinical studies. Ocrelizumab and daclizumab are in the late stages of phase III trials, and several other mAbs are in the early stages of clinical evaluation. mAbs have distinct structural characteristics (e.g. chimeric, humanized, fully human) and unique targets (e.g. blocking interactions, induction of signal transduction by receptor binding, complement-dependent cytotoxicity, antibody-dependent cell-mediated cytotoxicity) conferring different mechanisms of action in MS. Because of these differences, mAbs for MS do not constitute a single treatment class; each must be considered individually when selecting appropriate therapy. Furthermore, in reviewing the data from clinical studies of mAbs, attention should be drawn to use of different comparators (e.g. placebo or interferon β-1a) and study designs. Each mAb treatment has a unique administration schedule. In the decision to select the appropriate treatment for each individual MS patient, careful review of the benefits relative to risks of mAbs is balanced against the risk of development of MS-associated disability.
PubMed: 26600872
DOI: 10.1177/1756285615605429 -
Neurology and Therapy Dec 2016Multiple sclerosis (MS) is more common in women and can occur during childbearing years; thus, information on outcomes following exposure to MS therapy during pregnancy...
INTRODUCTION
Multiple sclerosis (MS) is more common in women and can occur during childbearing years; thus, information on outcomes following exposure to MS therapy during pregnancy is important. No formal studies of daclizumab have been conducted in pregnant women. Here, we report available nonclinical and clinical data on pregnancy outcomes from the daclizumab clinical study program.
METHODS
Reproductive and developmental toxicity studies were conducted in cynomolgus monkeys. Reports of pregnancies that occurred during the daclizumab clinical study program through March 9, 2015 were collated and summarized. In the event of pregnancy, daclizumab was discontinued and safety monitoring continued.
RESULTS
Studies in cynomolgus monkeys showed no daclizumab-related effects on maternal well-being, embryo-fetal development, indirect fertility end points, and pre- and postnatal development and growth. Across the clinical study program, 38 pregnancies were reported in 36 daclizumab-exposed women (on treatment ≤6 months from last dose); 20 resulted in live births and four (11%) in spontaneous abortions or miscarriages. One congenital heart defect (complex transposition of great vessels) occurred in one live birth (considered unrelated to daclizumab); daclizumab had been discontinued and intramuscular interferon beta-1a and lisinopril were used at conception. Eight women had an elective termination, two had an ectopic pregnancy, and two were lost to follow-up; two pregnancy outcomes are pending. Six additional pregnancies occurred in five women >6 months after their last daclizumab dose; in one additional pregnancy, exposure was unknown.
CONCLUSION
Spontaneous abortion rate in daclizumab-exposed women was consistent with early pregnancy loss in the general population (12%-26%). Data on pregnancies exposed to daclizumab do not suggest an increased risk of adverse fetal or maternal outcomes, although the numbers are too small for definitive conclusions. CLINICALTRIALS.
GOV IDENTIFIERS
NCT00390221, NCT01064401, NCT01462318, NCT00870740, NCT01051349, and NCT01797965.
FUNDING
Biogen and AbbVie Biotherapeutics Inc.
PubMed: 27411694
DOI: 10.1007/s40120-016-0048-2