Rational Engineering of Nissle 1917 as Live Biotherapeutic to Degrade Uremic Toxin Precursors.

Uremic toxins (UTs) are microbiota-derived metabolites that accelerate the progression of kidney damage in patients with chronic kidney disease (CKD). One of the major UTs involved in CKD progression is -cresol-sulfate (PCS), derived from dietary l-tyrosine (l-Tyr). Here, we engineered a probiotic strain of Nissle 1917, to convert l-Tyr to the nontoxic compound -coumaric acid via tyrosine ammonia lyase (TAL).

The live biotherapeutic SYNB1353 decreases plasma methionine via directed degradation in animal models and healthy volunteers.

Methionine is an essential proteinogenic amino acid, but its excess can lead to deleterious effects. Inborn errors of methionine metabolism resulting from loss of function in cystathionine β-synthase (CBS) cause classic homocystinuria (HCU), which is managed by a methionine-restricted diet. Synthetic biotics are gastrointestinal tract-targeted live biotherapeutics that can be engineered to replicate the benefits of dietary restriction.

Lactate limits CNS autoimmunity by stabilizing HIF-1α in dendritic cells.

Dendritic cells (DCs) have a role in the development and activation of self-reactive pathogenic T cells. Genetic variants that are associated with the function of DCs have been linked to autoimmune disorders, and DCs are therefore attractive therapeutic targets for such diseases. However, developing DC-targeted therapies for autoimmunity requires identification of the mechanisms that regulate DC function.

Phase I Study of SYNB1891, an Engineered E. coli Nissle Strain Expressing STING Agonist, with and without Atezolizumab in Advanced Malignancies.

Purpose: SYNB1891 is a live, modified strain of the probiotic Escherichia coli Nissle 1917 (EcN) engineered to produce cyclic dinucleotides under hypoxia, leading to STimulator of INterferon Genes (STING) activation in phagocytic antigen-presenting cells in tumors and activating complementary innate immune pathways.

Patients And Methods: This first-in-human study (NCT04167137) enrolled participants with refractory advanced cancers to receive repeat intratumoral injections of SYNB1891 either alone or in combination with atezolizumab, with the primary objective of evaluating the safety and tolerability of both regimens.

Results: Twenty-four participants received monotherapy across six cohorts, and 8 participants received combination therapy in two cohorts.

Engineered probiotics limit CNS autoimmunity by stabilizing HIF-1α in dendritic cells.

Dendritic cells (DCs) control the generation of self-reactive pathogenic T cells. Thus, DCs are considered attractive therapeutic targets for autoimmune diseases. Using single-cell and bulk transcriptional and metabolic analyses in combination with cell-specific gene perturbation studies we identified a negative feedback regulatory pathway that operates in DCs to limit immunopathology.

Robust performance of a live bacterial therapeutic chassis lacking the colibactin gene cluster.

E. coli Nissle (EcN) is a non-pathogenic probiotic bacterium of the Enterobacteriaceae family that has been used for over a century to promote general gut health. Despite the history of safe usage of EcN, concerns have been raised regarding the presence of the pks gene cluster, encoding the genotoxin colibactin, due to its association with colorectal cancer.

Targeted suppression of human IBD-associated gut microbiota commensals by phage consortia for treatment of intestinal inflammation.

Human gut commensals are increasingly suggested to impact non-communicable diseases, such as inflammatory bowel diseases (IBD), yet their targeted suppression remains a daunting unmet challenge. In four geographically distinct IBD cohorts (n = 537), we identify a clade of Klebsiella pneumoniae (Kp) strains, featuring a unique antibiotics resistance and mobilome signature, to be strongly associated with disease exacerbation and severity. Transfer of clinical IBD-associated Kp strains into colitis-prone, germ-free, and colonized mice enhances intestinal inflammation.

An engineered bacterial therapeutic lowers urinary oxalate in preclinical models and in silico simulations of enteric hyperoxaluria.

Enteric hyperoxaluria (EH) is a metabolic disease caused by excessive absorption of dietary oxalate leading to the formation of chronic kidney stones and kidney failure. There are no approved pharmaceutical treatments for EH. SYNB8802 is an engineered bacterial therapeutic designed to consume oxalate in the gut and lower urinary oxalate as a potential treatment for EH.

A New Natural Defense Against Airborne Pathogens.

We propose the nasal administration of calcium-enriched physiological salts as a new hygienic intervention with possible therapeutic application as a response to the rapid and tenacious spread of COVID-19. We test the effectiveness of these salts against viral and bacterial pathogens in animals and humans. We find that aerosol administration of these salts to the airways diminishes the exhalation of the small particles that face masks fail to filter and, in the case of an influenza swine model, completely block airborne transmission of disease.

Allergic Diseases Caused by Species in Patients with Cystic Fibrosis.

spp. are spore forming molds; a subset of which are clinically relevant to humans and can cause significant morbidity and mortality. causes chronic infection in patients with chronic lung disease such as asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis (CF).

A phase 1/1b study of PUR1900, an inhaled formulation of itraconazole, in healthy volunteers and asthmatics to study safety, tolerability and pharmacokinetics.

Aims: Oral itraconazole has variable pharmacokinetics and risks of adverse events associated with high plasma exposure. An inhalation formulation of itraconazole (PUR1900) is being developed to treat allergic bronchopulmonary aspergillosis, an allergic inflammatory disease occurring in asthmatics and patients with cystic fibrosis.

Methods: A 3-part, open-label Phase 1 study was conducted to evaluate safety, tolerability and pharmacokinetics of PUR1900.

Pulmonary and Regional Deposition of Nebulized and Dry Powder Aerosols in Ferrets.

The utilization of ferrets as a non-clinical model for disease is rapidly increasing within drug development. Many of these models include respiratory diseases that involve targeted drug delivery via nose-only inhalation. While the deposition patterns within other non-clinical models (mice, rats, canines, and non-human primates) have been well studied, the local and regional deposition of aerosols in ferrets has not been well characterized.

Toll-like receptor 2 is overexpressed in Familial Mediterranean fever patients and is inhibited by colchicine treatment.

Aim: To study the role of Toll-like receptor (TLR) 2 in Familial Mediterranean fever (FMF) inflammatory process.

Methods: TLR2 expression on monocytes of FMF attack-free patients (n = 20) and the effect of sera of FMF patients with an acute attack (n = 9) on TLR2 expression on monocytes of healthy donors were studied by flow cytometry (FACS). TLR2 expression was also studied in THP-1 cells, and TLR2 downstream signaling was studied by ELISA for the secretion of IL-1β and pro-inflammatory cytokines or by western blotting to measure nuclear factor (NF)-κB.

Particle size and gastrointestinal absorption influence tiotropium pharmacokinetics: a pilot bioequivalence study of PUR0200 and Spiriva HandiHaler.

Aims: Plasma pharmacokinetics permit the assessment of efficacy and safety of inhaled drugs, and possibly their bioequivalence to other inhaled products. Correlating drug product attributes to lung deposited dose is important to achieving equivalence. PUR0200 is a spray-dried formulation of tiotropium that enables more efficient lung delivery than Spiriva HandiHaler (HH).

Inhaled calcium salts inhibit tobacco smoke-induced inflammation by modulating expression of chemokines and cytokines.

Tobacco smoke-induced lung inflammation in patients with chronic obstructive pulmonary disease (COPD) worsens with disease progression and acute exacerbations caused by respiratory infections. Chronic therapies to manage COPD center on bronchodilators to improve lung function and inhaled corticosteroids (ICS) to help reduce the risk of exacerbations. Novel therapies are needed that reduce the underlying inflammation associated with COPD and the inflammation resulting from respiratory infections that worsen disease.

The pharmacokinetics, pharmacodynamics and tolerability of PUR0200, a novel tiotropium formulation, in chronic obstructive pulmonary disease.

Aims: PUR0200 is a tiotropium bromide formulation engineered with the iSPERSE dry powder delivery technology. PUR0200 is being developed as a bioequivalent alternative to tiotropium bromide, delivered using Spiriva® HandiHaler® (HH). We investigated the bronchodilator effects, pharmacokinetics and safety of PUR0200 in patients with chronic obstructive pulmonary disease (COPD).

Calcium restores the macrophage response to nontypeable haemophilus influenzae in chronic obstructive pulmonary disease.

Alveolar macrophages in chronic obstructive pulmonary disease (COPD) have demonstrated impaired bacterial phagocytosis and disordered cytokine secretion, which are calcium-dependent processes. We determined how calcium moderates the macrophage response to nontypeable Haemophilus influenzae (NTHI). We hypothesized that augmenting extracellular calcium during bacterial challenge would restore bacterial phagocytosis and cytokine secretion in monocyte-derived macrophages (MDMs) from subjects with COPD.

Lysosomal trafficking, antigen presentation, and microbial killing are controlled by the Arf-like GTPase Arl8b.

Antigen presentation and microbial killing are critical arms of host defense that depend upon cargo trafficking into lysosomes. Yet, the molecular regulators of traffic into lysosomes are only partly understood. Here, using a lysosome-dependent immunological screen of a trafficking shRNA library, we identified the Arf-like GTPase Arl8b as a critical regulator of cargo delivery to lysosomes.

A role for the B-cell CD74/macrophage migration inhibitory factor pathway in the immunomodulation of systemic lupus erythematosus by a therapeutic tolerogenic peptide.

Systemic lupus erythematosus (SLE) is an autoimmune disease that involves dysregulation of B and T cells. A tolerogenic peptide, designated hCDR1, ameliorates disease manifestations in SLE-afflicted mice. In the present study, the effect of treatment with hCDR1 on the CD74/macrophage migration inhibitory factor (MIF) pathway was studied.

A tolerogenic peptide down-regulates mature B cells in bone marrow of lupus-afflicted mice by inhibition of interleukin-7, leading to apoptosis.

Systemic lupus erythematosus (SLE) is an autoimmune disease mediated by T and B cells. It is characterized by a variety of autoantibodies and systemic clinical manifestations. A tolerogenic peptide, designated hCDR1, ameliorated the serological and clinical manifestations of SLE in both spontaneous and induced models of lupus.

Apical membrane maturation and cellular rosette formation during morphogenesis of the zebrafish lateral line.

Tissue morphogenesis and cell sorting are major forces during organ development. Here, we characterize the process of tissue morphogenesis within the zebrafish lateral line primordium, a migratory sheet of cells that gives rise to the neuromasts of the posterior lateral line organ. We find that cells within this epithelial tissue constrict actin-rich membranes and enrich apical junction proteins at apical focal points.

B-cell activating factor (BAFF) plays a role in the mechanism of action of a tolerogenic peptide that ameliorates lupus.

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by dysregulated immune responses mediated by T and B cells. A tolerogenic peptide, designated hCDR1, ameliorated the serological and clinical manifestations of SLE in mouse models of lupus. We investigated the role of B-cell activating factor (BAFF) in the beneficial effects of hCDR1.

Evasion of peptide, but not lipid antigen presentation, through pathogen-induced dendritic cell maturation.

Dendritic cells (DC) present lipid and peptide antigens to T cells on CD1 and MHC Class II (MHCII), respectively. The relative contribution of these systems during the initiation of adaptive immunity after microbial infection is not characterized. MHCII molecules normally acquire antigen and rapidly traffic from phagolysosomes to the plasma membrane as part of DC maturation, whereas CD1 molecules instead continually recycle between these sites before, during, and after DC maturation.