Producing recombinant proteins in Vibrio natriegens.

The diversity of chemical and structural attributes of proteins makes it inherently difficult to produce a wide range of proteins in a single recombinant protein production system. The nature of the target proteins themselves, along with cost, ease of use, and speed, are typically cited as major factors to consider in production. Despite a wide variety of alternative expression systems, most recombinant proteins for research and therapeutics are produced in a limited number of systems: Escherichia coli, yeast, insect cells, and the mammalian cell lines HEK293 and CHO. Recent interest in Vibrio natriegens as a new bacterial recombinant protein expression host is due in part to its short doubling time of ≤ 10 min but also stems from the promise of compatibility with techniques and genetic systems developed for E. coli. We successfully incorporated V. natriegens as an additional bacterial expression system for recombinant protein production and report improvements to published protocols as well as new protocols that expand the versatility of the system. While not all proteins benefit from production in V. natriegens, we successfully produced several proteins that were difficult or impossible to produce in E. coli. We also show that in some cases, the increased yield is due to higher levels of properly folded protein. Additionally, we were able to adapt our enhanced isotope incorporation methods for use with V. natriegens. Taken together, these observations and improvements allowed production of proteins for structural biology, biochemistry, assay development, and structure-based drug design in V. natriegens that were impossible and/or unaffordable to produce in E. coli.

Hypercholesterolaemia treated with inclisiran.

In this case report, a 31-year-old woman with heterozygous familial hypercholesterolaemia (FH) underwent treatment with statins and PCSK9 inhibitor but had to discontinue due to elevated creatine kinase levels and neurological and muscular side effects. In 2021, the patient received inclisiran therapy, the first known instance of its application in Denmark. No side effects were reported, and LDL cholesterol levels were significantly reduced. This case report highlights the potential of inclisiran as an effective and well-tolerated treatment for individuals with heterozygous FH.

Oral administration of CXCL12-expressing Limosilactobacillus reuteri improves colitis by local immunomodulatory actions in preclinical models.

Treatments of colitis, inflammation of the intestine, rely on induction of immune suppression associated with systemic adverse events, including recurrent infections. This treatment strategy is specifically problematic in the increasing population of patients with cancer with immune checkpoint inhibitor (ICI)-induced colitis, as immune suppression also interferes with the ICI-treatment response. Thus, there is a need for local-acting treatments that reduce inflammation and enhance intestinal healing. Here, we investigated the effect and safety of bacterial delivery of short-lived immunomodulating chemokines to the inflamed intestine in mice with colitis. Colitis was induced by dextran sulfate sodium (DSS) alone or in combination with ICI (anti-PD1 and anti-CTLA-4), and Limosilactobacillus reuteri R2LC (L. reuteri R2LC) genetically modified to express the chemokine CXCL12-1α (R2LC_CXCL12, emilimogene sigulactibac) was given perorally. In addition, the pharmacology and safety of the formulated drug candidate, ILP100-Oral, were evaluated in rabbits. Peroral CXCL12-producing L. reuteri R2LC significantly improved colitis symptoms already after 2 days in mice with overt DSS and ICI-induced colitis, which in benchmarking experiments was demonstrated to be superior to treatments with anti-TNF-α, anti-α4ß7, and corticosteroids. The mechanism of action involved chemokine delivery to Peyer's patches (PPs), confirmed by local CXCR4 signaling, and increased numbers of colonic, regulatory immune cells expressing IL-10 and TGF-ß1. No systemic exposure or engraftment could be detected in mice, and product feasibility, pharmacology, and safety were confirmed in rabbits. In conclusion, peroral CXCL12-producing L. reuteri R2LC efficiently ameliorates colitis, enhances mucosal healing, and has a favorable safety profile.NEW & NOTEWORTHY Colitis symptoms are efficiently reduced by peroral administration of probiotic bacteria genetically modified to deliver CXCL12 locally to the inflamed intestine in several mouse models.

Dental Implants in 18 Patients with Systemic Scleroderma: A Retrospective Radiographic Analysis Over a 5-Year Period with Focus on Marginal Bone Loss.

PURPOSE: Patients with systemic scleroderma (SSc) often suffer from premature tooth loss. The aim of this study was to radiologically investigate bone loss at dental implants in patients with SSc and compare it with data from the literature on healthy patients. MATERIALS AND METHODS: Mesial and distal bone level changes at implants were independently determined on panoramic and intraoral radiographs. They were double-checked after determination of evaluability by three different raters. Cohen's kappa was used to test for interrater reliability. Mean bone loss was estimated using linear regression analysis considering the patient as a random-effect implant and performed separately in predefined implant regions for different time points and for the mesial and distal sides of the implants. RESULTS: Mesial and distal bone level changes were analyzed in 61 implants using periapical and panoramic radiographs. In total, 114 radiographs from 18 patients were evaluable in both the mesial and distal regions. After a maximum observation period of 60 months, the mean peri-implant bone loss was 1.68 mm (range: 0.83 to 2.54 mm) at the distal aspect and 1.65 mm (range: 0.81 to 2.48 mm) at the mesial aspect in the right posterior mandible (region 44 to 47 [FDI numbering system]), whereas in the left posterior maxilla (regions 24 to 27), the mean peri-implant bone loss was 0.61 mm (range: 0.32 to 0.91 mm) at the distal aspect and 0.59 mm (range: 0.16 to 1.03 mm) at the mesial aspect. The mean bone loss 60 months after surgery was 1.05 mm (range: 0.85 to 1.25 mm). CONCLUSIONS: Marginal bone loss at implants in patients with SSc is comparable to data from the literature collected in healthy subjects.

Adapting recombinant bacterial alkaline phosphatase for nucleotide exchange of small GTPases.

The small GTPase Rat sarcoma virus proteins (RAS) are key regulators of cell growth and involved in 20-30% of cancers. RAS switches between its active state and inactive state via exchange of GTP (active) and GDP (inactive). Therefore, to study active protein, it needs to undergo nucleotide exchange to a non-hydrolysable GTP analog. Calf intestine alkaline phosphatase bound to agarose beads (CIP-agarose) is regularly used in a nucleotide exchange protocol to replace GDP with a non-hydrolysable analog. Due to pandemic supply problems and product shortages, we found the need for an alternative to this commercially available product. Here we describe how we generated a bacterial alkaline phosphatase (BAP) with an affinity tag bound to an agarose bead. This BAP completely exchanges the nucleotide in our samples, thereby demonstrating an alternative to the commercially available product using generally available laboratory equipment.

Efficient inhibition of SARS-CoV-2 strains by a novel ACE2-IgG4-Fc fusion protein with a stabilized hinge region

The novel severe acute respiratory syndrome (SARS)-like coronavirus (SARS-CoV-2) enters its host cells after binding to the angiotensin-converting enzyme 2 (ACE2) via its spike glycoprotein. This interaction is critical for virus entry and virus-host membrane fusion. Soluble ACE2 ectodomains bind and neutralize the virus but the short in vivo half-lives of soluble ACE2 limits its therapeutic use. Fusion of the fragment crystallizable (Fc) part of human immunoglobulin G (IgG) to the ACE2 ectodomain can prolong the in vivo half-life but bears the risk of unwanted Fc-receptor activation and antibody-dependent disease enhancement. Here, we describe optimized ACE2-Fc fusion constructs that avoid Fc-receptor binding by using IgG4-Fc as a fusion partner. The engineered ACE2-IgG4-Fc fusion proteins described herein exhibit promising pharmaceutical properties and a broad antiviral activity at single-digit nanomolar concentration. In addition, they allow to maintain the beneficial enzymatic activity of ACE2 and thus are very promising candidate antivirals broadly acting against coronaviruses.