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Over the past two decades, therapeutic antibodies have emerged as a rapidly expanding domain within the field of biologics. In silico tools that can streamline the process of antibody discovery and optimization are critical to support a pipeline that is growing more numerous and complex every year. High-quality structural information remains critical for the antibody optimization process, but antibody-antigen complex structures are often unavailable and in silico antibody docking methods are still unreliable. In this study, DeepAb, a deep learning model for predicting antibody Fv structure directly from sequence, was used in conjunction with single-point experimental deep mutational scanning (DMS) enrichment data to design 200 potentially optimized variants of an anti-hen egg lysozyme (HEL) antibody. We sought to determine whether DeepAb-designed variants containing combinations of beneficial mutations from the DMS exhibit enhanced thermostability and whether this optimization affected their developability profile. The 200 variants were produced through a robust high-throughput method and tested for thermal and colloidal stability (T onset , T m , T agg ), affinity (K D ) relative to the parental antibody, and for developability parameters (nonspecific binding, aggregation propensity, self-association). Of the designed clones, 91% and 94% exhibited increased thermal and colloidal stability and affinity, respectively. Of these, 10% showed a significantly increased affinity for HEL (5- to 21-fold increase) and thermostability (>2.5C increase in T m1 ), with most clones retaining the favorable developability profile of the parental antibody. Additional in silico tests suggest that these methods would enrich for binding affinity even without first collecting experimental DMS measurements. These data open the possibility of in silico antibody optimization without the need to predict the antibody-antigen interface, which is notoriously difficult in the absence of crystal structures.

Bispecific antibodies represent an increasingly large fraction of biologics in therapeutic development due to their expanded scope in functional capabilities. Asymmetric monovalent bispecific IgGs (bsIgGs) have the additional advantage of maintaining a native antibody-like structure, which can provide favorable pharmacology and pharmacokinetic profiles. The production of correctly assembled asymmetric monovalent bsIgGs, however, is a complex engineering endeavor due to the propensity for non-cognate heavy and light chains to mis-pair. Previously, we introduced the DuetMab platform as a general solution for the production of bsIgGs, which utilizes an engineered interchain disulfide bond in one of the C H 1-C L domains to promote orthogonal chain pairing between heavy and light chains. While highly effective in promoting cognate heavy and light chain pairing, residual chain mispairing could be detected for specific combinations of Fv pairs. Here, we present enhancements to the DuetMab design that improve chain pairing and production through the introduction of novel electrostatic steering mutations at the C H 1-C L interface with lambda light chains (C H 1-C λ ). These mutations work together with previously established charge-pair mutations at the C H 1-C L interface with kappa light chains (C H 1-C κ ) and Fab disulfide engineering to promote cognate heavy and light chain pairing and enable the reliable production of bsIgGs. Importantly, these enhanced DuetMabs do not require engineering of the variable domains and are robust when applied to a panel of bsIgGs with diverse Fv sequences. We present a comprehensive biochemical, biophysical, and functional characterization of the resulting DuetMabs to demonstrate compatibility with industrial production benchmarks. Overall, this enhanced DuetMab platform substantially streamlines process development of these disruptive biotherapeutics.

Background: The treatment of persistent air leak is a challenge. Herein, we reported the combined intrabronchial and intrapleural injection of fibrin glue using fiber bronchoscopy to seal off an alveolar pleura fistula developed following necrotizing pneumonia in high-risk patient., Case Presentation: A 74-year-old man was intubated in emergency for acute ischemic stroke. Percutaneous dilatational tracheostomy was then performed, and 15 days later patient returned to spontaneous breathing. However, he developed alveolar pleural fistula following necrotizing pneumonia with persistent air leaks. The intrabronchial and intrapleural injection of fibrin glue using fiber bronchoscopy sealed off the alveolar pleura fistula after that other endoscopic treatments as bronchial valve and intrabronchial fibrin glue application had failed., Conclusions: Our strategy is safe and easy to reproduce. It represents an additional method in the armamentarium of the physicians for the management of PAL when all standard strategies are unfeasible or fail.

Objectives: To evaluate if the pre-emptive administration of ketamine would potentiate the effect of intravenous morphine analgesia in the management of post-thoracotomy pain., Methods: This was a unicentre, double-blind, placebo-controlled, parallel-group, prospective study. Patients were randomly assigned to receive 1 mg/kg ketamine (ketamine group) or an equivalent dose of normal saline (placebo group) before thoracotomy in 1:1 ratio. All patients received postoperatively intravenous morphine administration as additional analgesic regimen. Primary end-point was the pain relief measured with Visual Analogue Scale at rest. The secondary end-points were the reduction of inflammatory response expressed by plasma C-reactive protein levels, the morphine consumption and the rate of side effects. The measurements were carried out 6, 12, 24, 36 and 48 hours postoperatively., Results: A total of 75 patients were randomized of whom 38 were allocated to ketamine group and 37 to placebo group. Baseline characteristics were comparable. Ketamine compared with placebo group showed a significant reduction of pain scores (P = 0.01), C-reactive protein (P < 0.001) and morphine consumption (P < 0.001). No acute psychological side effects related to the use of ketamine were registered., Conclusions: The administration of ketamine before surgery may be an effective adjunct to intravenous morphine analgesia in acute post-thoracotomy pain management. In ketamine group, satisfaction of pain relief was significantly higher with a significant reduction of inflammatory response and morphine consumption compared with placebo group. Our results, if confirmed by larger studies, may be of clinical relevance in situations where epidural analgesia or other analgesic procedures different from systemic opioid analgesia are unavailable or contraindicated., (© The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.)

Gynaecologic oncology day surgery deals primarily with the diagnosis of endometrial, cervical, vulvar and vaginal tumors. Conscious sedation is an important technique used in gynaecologic oncology day surgery. It is often associated with regional anaesthesia. The goals of conscious sedation are to provide effective pain control with complete safety, reduction of the recovery time, of the infection risk and cost. Since the consequences of the immunosuppressive effects of the opiates and the surgical stress could lead to an increased susceptibility to post-operative infections and a possible lack of immunological defence in the cancer patients, we investigated the possibility of eliminating the administration of opiates during minor operations in gynaecologic oncology day surgery. In this study, 400 patients, aged between 35 and 77 years, underwent surgery using sedation at the day hospital annexed to the Gynaecology and Obstetrics Department of the 2nd University of Naples, Italy. The patients were randomized into two equal study groups, according to a computer-generated randomised list. All patients were seen by the consultant anaesthetist three days before surgery. In all cases, during surgery, we monitored the main vital parameters such as ECG, HR and RR, BT, BP and SO. The drugs commonly used were: opioids, hypnotics and benzodiazepines, associated or not, with local anaesthetics. By using these drugs, pain and anxiety were reduced, sedation and amnesia were accomplished. In our experience, conscious sedation seems to be the best choice in gynaecologic oncology day surgery because it presents low toxicity, is short acting and readily reversible, has a low cost and, finally, because it is more comfortable for the patients. Moreover, it is possible to eliminate the administration of opiates during conscious sedation for less invasive surgical procedures.

In 1996, the vaccination coverage against hepatitis B virus among 3,157 healthcare workers in Italy was inversely related to the level of hepatitis B virus endemicity in the area of residence. Youngest age and lowest years of employment were independent predictors of the likelihood of vaccine acceptance.