Evaluation of low volume sampling devices for a pharmacodynamic biomarker analysis: Challenges and solutions.

Low volume sampling technologies have gained popularity as they are minimally invasive, reduce patient burden, enhance population diversity, and have the potential to facilitate decentralized clinical trials. Herein, we validated a Gyrolab assay to measure soluble Mucosal Addressin Cell Adhesion Molecule 1 (sMAdCAM-1) in dried blood samples collected using two low volume sampling devices, Mitra and Tasso-M20. This validated assay was implemented in a proof-of-concept study to compare three low volume sampling devices (Mitra, Tasso-M20 and TassoOne Plus) with serum collected via venipuncture from healthy volunteers receiving etrolizumab.

Differential expression of small bowel TGFβ1 and TGFβ3 characterizes intestinal strictures in patients with fibrostenotic Crohn's disease.

Small bowel strictures remain a debilitating consequence of Crohn's disease and contribute to poor outcomes for patients. Recently, TGFβ has been identified as an important driver of intestinal fibrosis. We studied the localization of TGFβ isoforms in ileal strictures of patients with Crohn's disease using in situ hybridization to understand TGFβ's role in stricture formation.

A Phase 1a Study to Evaluate Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of RO7303509, an Anti-TGFβ3 Antibody, in Healthy Volunteers.

Introduction: Transforming growth factor beta (TGFβ) cytokines (TGFβ1, TGFβ2, and TGFβ3) play critical roles in tissue fibrosis. However, treatment with systemic pan-TGFβ inhibitors have demonstrated unacceptable toxicities. In this study, we evaluated the safety, tolerability, pharmacokinetics, and pharmacodynamics of RO7303509, a high-affinity, TGFβ3-specific, humanized immunoglobulin G1 monoclonal antibody, in healthy adult volunteers (HVs).

Association study of human leukocyte antigen variants and idiopathic pulmonary fibrosis.

Introduction: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia marked by progressive lung fibrosis and a poor prognosis. Recent studies have highlighted the potential role of infection in the pathogenesis of IPF, and a prior association of the gene with idiopathic fibrotic interstitial pneumonia (including IPF) has been reported. Owing to the important role that the human leukocyte antigen (HLA) region plays in the immune response, here we evaluated if HLA genetic variation was associated specifically with IPF risk.

Genome-wide SNP-sex interaction analysis of susceptibility to idiopathic pulmonary fibrosis.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic lung condition that is more prevalent in males than females. The reasons for this are not fully understood, with differing environmental exposures due to historically sex-biased occupations, or diagnostic bias, being possible explanations. To date, over 20 independent genetic variants have been identified to be associated with IPF susceptibility, but these have been discovered when combining males and females.

Association study of human leukocyte antigen (HLA) variants and idiopathic pulmonary fibrosis.

Introduction: Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia marked by progressive lung fibrosis and a poor prognosis. Recent studies have highlighted the potential role of infection in the pathogenesis of IPF and a prior association of the gene with idiopathic fibrotic interstitial pneumonia (including IPF) has been reported. Due to the important role that the Human Leukocyte Antigen (HLA) region plays in the immune response, here we evaluated if HLA genetic variation was associated specifically with IPF risk.

Utilizing PK and PD Biomarkers to Guide the First-in-Human Starting Dose Selection of MTBT1466A: A Novel Humanized Monoclonal Anti-TGFβ3 Antibody for the Treatment of Fibrotic Diseases.

MTBT1466A is a high-affinity TGFβ3-specific humanized IgG1 monoclonal antibody with reduced Fc effector function, currently under investigation in clinical trials as a potential anti-fibrotic therapy. Here, we characterized the pharmacokinetics (PK) and pharmacodynamics (PD) of MTBT1466A in mice and monkeys and predicted the PK/PD of MTBT1466A in humans to guide the selection of the first-in-human (FIH) starting dose. MTBT1466A demonstrated a typical IgG1-like biphasic PK profile in monkeys, and the predicted human clearance of 2.

Prognostic and predictive biomarkers for patients with idiopathic pulmonary fibrosis treated with pirfenidone: post-hoc assessment of the CAPACITY and ASCEND trials.

Background: Heterogeneity in the progression of idiopathic pulmonary fibrosis (IPF) might reflect diversity in underlying pathobiology, and represents a major challenge in the prediction of clinical progression and treatment benefit. Previous studies have found peripheral blood concentrations of several protein biomarkers to be prognostic for overall survival duration in patients with IPF, but these findings have generally not been directly compared and replicated between cohorts. We aimed to use the pivotal trials for pirfenidone to evaluate prognostic and predictive properties of biomarkers across multiple endpoints, and whether they are modulated by pirfenidone treatment.

Oncogenic RAS pathway activation promotes resistance to anti-VEGF therapy through G-CSF-induced neutrophil recruitment.

Granulocyte-colony stimulating factor (G-CSF) promotes mobilization of CD11b(+)Gr1(+) myeloid cells and has been implicated in resistance to anti-VEGF therapy in mouse models. High G-CSF production has been associated with a poor prognosis in cancer patients. Here we show that activation of the RAS/MEK/ERK pathway regulates G-CSF expression through the Ets transcription factor.

Live imaging of the Drosophila spermatogonial stem cell niche reveals novel mechanisms regulating germline stem cell output.

Adult stem cells modulate their output by varying between symmetric and asymmetric divisions, but have rarely been observed in living intact tissues. Germline stem cells (GSCs) in the Drosophila testis are anchored to somatic hub cells and were thought to exclusively undergo oriented asymmetric divisions, producing one stem cell that remains hub-anchored and one daughter cell displaced out of the stem cell-maintaining micro-environment (niche). We developed extended live imaging of the Drosophila testis niche, allowing us to track individual germline cells.

Make room for dedifferentiation.

The reversal of cellular differentiation, or dedifferentiation, has fascinated biologists for many decades. While cells can be re-programmed extensively in culture, examples of in vivo dedifferentiation have recently emerged in both vertebrate and invertebrate systems, allowing for analysis of this intriguing process under more physiologically relevant conditions. Studies suggest that dedifferentiation occurs not only during large-scale cellular regeneration, but also at low levels to replenish stem cells lost due to normal turnover.

Dedifferentiating spermatogonia outcompete somatic stem cells for niche occupancy in the Drosophila testis.

Differentiating cells can dedifferentiate to replace stem cells in aged or damaged tissues, but the underlying mechanisms are unknown. In the Drosophila testis, a cluster of stromal cells called the hub creates a niche by locally activating Janus kinase-signal transducer and activator of transcription (Jak-STAT) signaling in adjacent germline and somatic stem cells. Here, we establish a system to study spermatogonial dedifferentiation.

Jak-STAT regulation of male germline stem cell establishment during Drosophila embryogenesis.

Germline stem cells (GSCs) in Drosophila are descendants of primordial germ cells (PGCs) specified during embryogenesis. The precise timing of GSC establishment in the testis has not been determined, nor is it known whether mechanisms that control GSC maintenance in the adult are involved in GSC establishment. Here, we determine that PGCs in the developing male gonad first become GSCs at the embryo to larval transition.

Identification of five mouse mu-opioid receptor (MOR) gene (Oprm1) splice variants containing a newly identified alternatively spliced exon.

The mouse mu-opioid receptor gene, Oprm1, currently contains 18 recognized alternatively spliced exons [Doyle, G.A., Sheng, X.

Identification of three mouse mu-opioid receptor (MOR) gene (Oprm1) splice variants containing a newly identified alternatively spliced exon.

The mouse mu-opioid receptor gene, Oprm1, is recognized currently to contain 17 alternatively spliced exons that generate 24 splice variants encoding at least 11 morphine-binding isoforms of the receptor. Here, we identify three new MOR splice variants that contain a previously undescribed exon, exon 18, and provide evidence that they are expressed in two mouse strains. The transcripts containing the newly identified exon 18 encode two new putative mu-opioid receptor isoforms, MOR-1V and MOR-1W.

Identification and functional significance of polymorphisms in the mu-opioid receptor gene (Oprm) promoter of C57BL/6 and DBA/2 mice.

C57BL/6J and DBA/2J mice demonstrate differences in morphine preference when tested in a two-bottle choice paradigm. Quantitative trait loci (QTL) mapping suggested the proximal region of chromosome 10 was responsible for 41% of the observed genetic variance. The mu-opioid receptor (MOR) gene (Oprm) maps to this region and is a prime candidate for explaining the QTL.