Publications by authors named "Stephen Alves"

Pathologic T cell-B cell interactions drive disease in systemic lupus erythematosus (SLE). The T cells that activate B cell responses include T peripheral helper (Tph) and T follicular helper (Tfh) cells, yet the developmental and clonal relationships between these B cell-helper T cell populations are unclear. Here we use T cell receptor (TCR) profiling to demonstrate clonal overlap between Tph and Tfh cells in the circulation of patients with SLE.

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Systemic lupus erythematosus (SLE) is prototypical autoimmune disease driven by pathological T cell-B cell interactions. Expansion of T follicular helper (T) and T peripheral helper (T) cells, two T cell populations that provide help to B cells, is a prominent feature of SLE. Human T and T cells characteristically produce high levels of the B cell chemoattractant CXCL13 (refs.

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Disruptions in the gut epithelial barrier can lead to the development of chronic indications such as inflammatory bowel disease (IBD). Historically, barrier function has been assessed in cancer cell lines, which do not contain all human intestinal cell types, leading to poor translatability. To bridge this gap, we adapted human primary gut organoids grown as monolayers to quantify transcription factor phosphorylation, gene expression, cytokine production, and barrier function.

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Objectives: To investigate the immune cell profiles of patients with systemic lupus erythematosus (SLE), and to identify longitudinal changes in those profiles over time.

Methods: We employed mass cytometry with 3 different panels of 38-39 markers (an immunophenotyping panel, a T cell/monocyte panel, and a B cell panel) in cryopreserved peripheral blood mononuclear cells (PBMCs) from 9 patients with early SLE, 15 patients with established SLE, and 14 controls without autoimmune disease. We used machine learning-driven clustering, flow self-organizing maps, and dimensional reduction with t-distributed stochastic neighbor embedding to identify unique cell populations in early SLE and established SLE.

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The approvals of idelalisib and duvelisib have validated PI3Kδ inhibitors for the treatment for hematological malignancies driven by the PI3K/AKT pathway. Our program led to the identification of structurally distinct heterocycloalkyl purine inhibitors with excellent isoform and kinome selectivity; however, they had high projected human doses. Improved ligand contacts gave potency enhancements, while replacement of metabolic liabilities led to extended half-lives in preclinical species, affording PI3Kδ inhibitors with low once-daily predicted human doses.

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Viral-induced exacerbation of asthma remains a major cause of hospitalization and mortality. New human-relevant models of the airways are urgently needed to understand how respiratory infections may trigger asthma attacks and to advance treatment development. Here, we describe a new human-relevant model of rhinovirus-induced asthma exacerbation that recapitulates viral infection of asthmatic airway epithelium and neutrophil transepithelial migration, and enables evaluation of immunomodulatory therapy.

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Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by pathologic T cell-B cell interactions and autoantibody production. Defining the T cell populations that drive B cell responses in SLE may enable design of therapies that specifically target pathologic cell subsets. Here, we evaluated the phenotypes of CD4+ T cells in the circulation of 52 SLE patients drawn from multiple cohorts and identified a highly expanded PD-1hiCXCR5-CD4+ T cell population.

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We leveraged a clinical pharmacokinetic (PK)/pharmacodynamics (PD)/efficacy relationship established with an oral phosphatidylinositol 3-kinase (PI3K) inhibitor (Idelalisib) in a nasal allergen challenge study to determine whether a comparable PK/PD/efficacy relationship with PI3K inhibitors was observed in preclinical respiratory models of type 2 T helper cell (TH2) and type 1 T helper cell (TH1) inflammation. Results from an in vitro rat blood basophil (CD63) activation assay were used as a PD biomarker. IC values for PI3K inhibitors, MSD-496486311, MSD-126796721, Idelalisib, and Duvelisib, were 1.

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Crohn's disease (CD) is a chronic disorder of the gastrointestinal tract characterized by inflammation and intestinal epithelial injury. Loss of function mutations in the intracellular bacterial sensor NOD2 are major risk factors for the development of CD. In the absence of robust bacterial recognition by NOD2 an inflammatory cascade is initiated through alternative PRRs leading to CD.

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While the immune system is essential for the maintenance of the homeostasis, health and survival of humans, aberrant immune responses can lead to chronic inflammatory and autoimmune disorders. Pharmacological modulation of drug targets in the immune system to ameliorate disease also carry a risk of immunosuppression that could lead to adverse outcomes. Therefore, it is important to understand the 'immune fingerprint' of novel therapeutics as they relate to current and, clinically used immunological therapies to better understand their potential therapeutic benefit as well as immunosuppressive ability that might lead to adverse events such as infection risks and cancer.

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Background And Purpose: Asthma presents as a heterogeneous syndrome characterized by airway obstruction, inflammation and hyper-reactivity (AHR). Spleen tyrosine kinase (Syk) mediates allergen-induced mast cell degranulation, a central component of allergen-induced inflammation and AHR. However, the role of Syk in IgE-mediated constriction of human small airways remains unknown.

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The androgen receptor (AR) is a member of the nuclear hormone receptor super family of transcription factors. Androgens play an essential role in the development, growth, and maintenance of male sex organs, as well as the musculoskeletal and central nervous systems. Yet with advancing age, androgens can drive the onset of prostate cancer, the second leading cause of cancer death in males within the United States.

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Here we describe the development of a human lung 'small airway-on-a-chip' containing a differentiated, mucociliary bronchiolar epithelium and an underlying microvascular endothelium that experiences fluid flow, which allows for analysis of organ-level lung pathophysiology in vitro. Exposure of the epithelium to interleukin-13 (IL-13) reconstituted the goblet cell hyperplasia, cytokine hypersecretion and decreased ciliary function of asthmatics. Small airway chips lined with epithelial cells from individuals with chronic obstructive pulmonary disease recapitulated features of the disease such as selective cytokine hypersecretion, increased neutrophil recruitment and clinical exacerbation by exposure to viral and bacterial infections.

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Objectives: Human airway epithelial cells are the principal target of human rhinovirus (HRV), a common cold pathogen that triggers the majority of asthma exacerbations. The objectives of this study were 1) to evaluate an in vitro air liquid interface cultured human airway epithelial cell model for HRV infection, and 2) to identify gene expression patterns associated with asthma intrinsically and/or after HRV infection using this model.

Methods: Air-liquid interface (ALI) human airway epithelial cell cultures were prepared from 6 asthmatic and 6 non-asthmatic donors.

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Prostate cancer (PCa) initially responds to inhibition of androgen receptor (AR) signaling, but inevitably progresses to hormone ablation-resistant disease. Much effort is focused on optimizing this androgen deprivation strategy by improving hormone depletion and AR antagonism. However we found that bicalutamide, a clinically used antiandrogen, actually resembles a selective AR modulator (SARM), as it partially regulates 24% of endogenously 5α-dihydrotestosterone (DHT)-responsive genes in AR(+) MDA-MB-453 breast cancer cells.

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Myostatin is a highly conserved member of the transforming growth factor-β ligand family known to regulate muscle growth via activation of activin receptors. A fusion protein consisting of the extracellular ligand-binding domain of activin type IIB receptor with the Fc portion of human immunoglobulin G (ActRIIB-Fc) was used to inhibit signaling through this pathway. Here, we study the effects of this fusion protein in adult, 18-month-old, and orchidectomized mice.

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Estrogen Receptor α (ERα) and Estrogen Receptor β (ERβ) are steroid nuclear receptors that transduce estrogen signaling to control diverse physiological processes linked to reproduction, bone remodeling, behavior, immune response and endocrine-related diseases. In order to differentiate between ERα and ERβ mediated effects in vivo, ER subtype selective biomarkers are essential. We utilized ERα knockout (AERKO) and ERβ knockout (BERKO) mouse liver RNA and genome wide profiling to identify novel ERα selective serum biomarker candidates.

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Background: Age-related sarcopenia is a disease state of loss of muscle mass and strength that affects physical function and mobility leading to falls, fractures, and disability. The need for therapies to treat age-related sarcopenia has attracted intensive preclinical research. To facilitate the discovery of these therapies, we have developed a non-invasive rat muscle functional assay system to efficiently measure muscle force and evaluate the efficacy of drug candidates.

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Both the physiological role of muscarinic receptors for bladder function and the therapeutic efficacy of antimuscarinic agents for overactive bladder syndrome are well documented. We investigated the effect of antimuscarinic agents with different subtype selectivity on urodynamic parameters in nonhuman primates and rodents and compared plasma levels of these agents between species. Anesthetized rhesus monkeys were transurethrally catheterized, and the bladder was infused with saline.

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Effects of estradiol benzoate (EB), ERα-selective agonist, propyl pyrazole triol (PPT) and ERβ-selective agonists, diarylpropionitrile (DPN) and Compound 19 (C-19) on memory were investigated in OVX rats using object recognition (OR) and placement (OP) memory tasks. Treatments were acute (behavior 4h later) or sub chronic (daily injections for 2 days with behavior 48 h later). Objects were explored in sample trials (T1), and discrimination between sample (old) and new object/location in recognition trials (T2) was examined after 2-4h inter-trial delays.

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We assessed the effects of subtype-selective ER agonists on monoamine levels in discrete regions of the female rat brain. Ovariectomized (ovx) rats were treated for 4 days with vehicle, 17β-estradiol (E; 0.05mg/kg), an ERβ agonist (C19; 3mg/kg) or an ERα agonist (PPT; 3mg/kg) and samples from brain regions were assessed for monoamines and metabolites.

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Immunocytochemical studies have shown that nuclear and extranuclear estrogen receptors (ERs) are present in several extrahypothalamic brain regions. The goal of this study was to determine the subcellular location of functional ERs, particularly extranuclear ERs, by demonstrating (125)I-estradiol binding in the rat forebrain and medullary sections prepared for light and electron microscopic autoradiography. Some sections were immunocytochemically labeled with the catecholamine-synthesizing enzyme, tyrosine hydroxylase (TH), prior to the autoradiographic procedure.

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Blood pressure in women increases after menopause, and sympathetic tone in female rats decreases with estrogen injections in the rostral ventrolateral medulla (RVLM) region that contains bulbospinal C1 adrenergic neurons and is involved in blood pressure control. We investigated the anatomical and physiological basis for estrogen effects in the RVLM. Neurons with alpha- or beta-subtypes of estrogen receptor (ER) immunoreactivity (-ir) overlapped in distribution with tyrosine hydroxylase (TH)-containing C1 neurons.

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Several lines of evidence indicate that estrogen affects hippocampal synaptic plasticity through rapid nongenomic mechanisms, possibly by binding to plasma membrane estrogen receptors (ERs). We have previously shown that ERalpha immunoreactivity (ir) is in select interneuron nuclei and in several extranuclear locations, including dendritic spines and axon terminals, within the rat hippocampal formation (Milner et al., [2001] J Comp Neurol 429:355).

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