Tracing the footprints of SARS-CoV-2 in oceanic waters

The detection of SARS-CoV-2 in water environments has predominantly focused on wastewater, neglecting its presence in oceanic waters. This study aimed to fill this knowledge gap by investigating the occurrence of SARS-CoV-2 in remote sea and oceanic waters, at large distances from the coastline. Forty-three 500-liter samples were collected between May 2022 and January 2023 from the Atlantic Ocean, the Mediterranean Sea, the Arctic region, the Persian Gulf and the Red Sea. Using molecular detection methods including real-time RT-qPCR and nested PCR followed by sequencing, we successfully detected SARS-CoV-2 RNA in 7 of the 43 marine water samples (16.3 %), and specifically in samples taken from the Atlantic Ocean and the Mediterranean Sea. The estimated concentrations of SARS-CoV-2 genome copies in the positive samples ranged from 6 to 470 per 100 l. The presence of mutations characteristic of the Omicron variant was identified in these samples by amplicon sequencing. These findings provide evidence of the unforeseen presence of SARS-CoV-2 in marine waters even at distances of miles from the coastline and in open ocean waters. It is important to consider that these findings only display the occurrence of SARS-CoV-2 RNA, and further investigations are required to assess if infectious virus can be present in the marine environment.

High throughput purification of monoclonal recombinant antibodies using a Protein-A coated membrane plate system

The therapeutic use of monoclonal antibodies (mAbs) ranges from cancer treatment to immune-mediated conditions, covering infectious and cardiovascular disorders, among others. The development of improved methods for therapeutic antibody discovery has accelerated the identification of numerous mAbs: a discovery campaign can be deeply mined, resulting in hundreds, even thousands, of potential antibody leads for a given target of interest. High throughput mAb expression and purification methods are required for the rapid validation of those leads. In this work, we describe the implementation of a Protein-A coated membrane plate system, the Purexa™ AHT membrane plate, for robust preparative purification of hundreds of recombinant mAbs, without the need for automation. The high efficiency (>80%) recovery generated sufficient mAb for downstream screening analyses such as ELISA and surface plasmon resonance (SPR). This new system allows the functional validation of hundreds of lead antibodies from discovery campaigns in a timely manner regardless of operational size.

Insights into next generation sequencing guided antibody selection strategies

Therapeutic antibody discovery often relies on in-vitro display methods to identify lead candidates. Assessing selected output diversity traditionally involves random colony picking and Sanger sequencing, which has limitations. Next-generation sequencing (NGS) offers a cost-effective solution with increased read depth, allowing a comprehensive understanding of diversity. Our study establishes NGS guidelines for antibody drug discovery, demonstrating its advantages in expanding the number of unique HCDR3 clusters, broadening the number of high affinity antibodies, expanding the total number of antibodies recognizing different epitopes, and improving lead prioritization. Surprisingly, our investigation into the correlation between NGS-derived frequencies of CDRs and affinity revealed a lack of association, although this limitation could be moderately mitigated by leveraging NGS clustering, enrichment and/or relative abundance across different regions to enhance lead prioritization. This study highlights NGS benefits, offering insights, recommendations, and the most effective approach to leverage NGS in therapeutic antibody discovery.

Biochemical and Functional Characterization of the Three Zebrafish Transglutaminases 2

Transglutaminase 2 (TG2) is a multifunctional protein widely distributed in various tissues and involved in many physiological and pathological processes. However, its actual role in biological processes is often controversial as TG2 shows different effects in these processes depending on its localization, cell type, or experimental conditions. We characterized the enzymatic and functional properties of TG2 proteins expressed in Danio rerio (zebrafish) to provide the basis for using this established animal model as a reliable tool to characterize TG2 functions in vivo. We confirmed the existence of three genes orthologous to human TG2 (zTGs2) in the zebrafish genome and their expression and function during embryonic development. We produced and purified the zTGs2s as recombinant proteins and showed that, like the human enzyme, zTGs2 catalyzes a Ca2+ dependent transamidation reaction that can be inhibited with TG2-specific inhibitors. In a cell model of human fibroblasts, we also demonstrated that zTGs2 can mediate RGD-independent cell adhesion in the extracellular environment. Finally, we transfected and selected zTGs2-overexpressing HEK293 cells and demonstrated that intracellular zTGs2 plays a very comparable protective/damaging role in the apoptotic process, as hTG2. Overall, our results suggest that zTGs2 proteins behave very similarly to the human ortholog and pave the way for future in vivo studies of TG2 functions in zebrafish.

Comorbidity and in-hospital mortality in peritoneal dialysis patients: data of the Emilia Romagna region of Italy

OBJECTIVE

Kidney failure increases in-hospital mortality (IHM); however, comorbidity is crucial for predicting mortality in dialysis patients. Our aim was to evaluate the impact of comorbidity, assessed by modified Elixhauser index (mEI), Charlson Comorbidity Index (CCI), and age-adjusted CCI, on IHM in a cohort of peritoneal dialysis patients admitted to hospitals of the Emilia Romagna region (ERR) of Italy.

PATIENTS AND METHODS

All hospital admissions of peritoneal dialysis patients recorded between 2007 and 2021 in the ERR database were analyzed. The International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) was used for detecting diagnoses and procedures, and the inclusion criterion was code 5498. Comorbidity burden was evaluated by three different scores, and hemodialysis (HD) treatment need was considered. IHM was our outcome.

RESULTS

During the 15 years of the study, 3,242 hospitalized peritoneal dialysis patients (62.7% males) were evaluated. Mean age was 62.8±20.6 years, 9.6% underwent HD, and IHM was 5.9% (n=192). IHM mortality was stable throughout the study period. Deceased subjects were older, were hospitalized longer, had a higher comorbidity burden, and had a higher percentage of HD treatment needs than survivors. Age, male sex, comorbidity burden, and HD treatment were predictors of IHM. Receiver operating characteristics (ROC) analysis confirmed the impact of comorbidity burden on IHM, especially when age was considered.

CONCLUSIONS

We conclude that in male, elderly hospitalized peritoneal dialysis patients with failing dialysis technique, comorbidity burden should be considered being a predictor of IHM.

SARS-CoV-2 caused a surge in antibiotic consumption causing a silent pandemic inside the pandemic. A retrospective analysis of Italian data in the first half of 2022

BACKGROUND

The phenomenon of antibiotic resistance shows no sign of stopping, despite global policies to combat it that have been in place for several years. The risk of forms of pathogenic microorganisms that are increasingly resistant to common antibiotics has led health authorities around the world to pay greater attention to the phenomenon. The worrying situation, has led to further recommendations from the World Health Organization (WHO) and national recommendations in Italy through the new National Plan against Antibiotic Resistance 2022-2025 (PNCAR 2022-2025).

AIM

This manuscript aims to raise the awareness of all health professionals to follow what is suggested by regulatory agencies and scientific societies.

METHOD

We conducted a retrospective study of antibiotic pharmacoutilization in Italy, in the Campania region at the Azienda Sanitaria Locale (ASL) Napoli 3 Sud, on consumption in the first half of 2022 in a population of more than 1 million people.

RESULT

The results indicate that consumption, based on defined daily doses (DDDs), is above the national average. Probably the COVID-19 pandemic has influenced this growth in prescriptions.

CONCLUSIONS

Our study suggests an informed and appropriate use of antibiotics, so as to embark on a virtuous path in the fight against antibiotic resistance.

Direct selection of functional fluorescent-protein antibody fusions by yeast display

Antibodies are important reagents for research, diagnostics, and therapeutics. Many examples of chimeric proteins combining the specific target recognition of antibodies with complementing functionalities such as fluorescence, toxicity or enzymatic activity have been described. However, antibodies selected solely on the basis of their binding specificities are not necessarily ideal candidates for the construction of chimeras. Here, we describe a high throughput method based on yeast display to directly select antibodies most suitable for conversion to fluorescent chimera. A library of scFv binders was converted to a fluorescent chimeric form, by cloning thermal green protein into the linker between VH and VL, and directly selecting for both binding and fluorescent functionality. This allowed us to directly identify antibodies functional in the single chain TGP format, that manifest higher protein expression, easier protein purification, and one-step binding assays.

Determining the affinities of high-affinity antibodies using KinExA and surface plasmon resonance

Accurate and efficient affinity measurement techniques are essential for the biophysical characterization of therapeutic monoclonal antibodies, one of the fastest growing drug classes. Surface plasmon resonance (SPR) is widely used for determining antibody affinity, but does not perform well with extremely high affinity (low picomolar to femtomolar range) molecules. In this study, we compare the SPR-based Carterra LSA and the kinetic exclusion assay (KinExA) for measuring the affinities of 48 antibodies generated against the SARS-CoV-2 receptor-binding domain. These data reveal that high-affinity antibodies can be generated straight from selections using high-quality in vitro library platforms with 54% correspondence between affinities measured using LSA and KinExA. Generally, where there was a 2-fold or greater difference between LSA and KinExA, KinExA reported that affinities were tighter. We highlight the differences between LSA and KinExA, identifying the benefits and pitfalls of each in terms of dynamic range and throughput. Furthermore, we demonstrate for the first time that single-point screening with KinExA can significantly improve throughput while maintaining a strong correlation with full binding curve equilibrium measurements, enabling the accurate rank-ordering of clones with exceptionally tight binding properties.

The Effect of Crackers Enriched with Camelina Sativa Oil on Omega-3 Serum Fatty Acid Composition in Older Adults: A Randomized Placebo-Controlled Pilot Trial

BACKGROUND

Camelina sativa oil is one of the richest dietary sources of omega-3, with polyunsaturated fatty acids amounts of over 50%, linolenic acid content of around 40-45%, and linoleic acid of about 15%. Moreover, this oil is a valuable source of antioxidants which provide oxidative stability. All those features raise interest in considering Camelina oil as an alternative and sustainable oil source providing stable omega-3-rich emulsions for functional food production.

OBJECTIVES

The present study aimed to investigate the effects of Camelina oil-enriched crackers on serum omega-3 concentration, inflammatory markers and serum lipid profile.

DESIGN

Randomized placebo-controlled pilot trial.

SETTING

Research and Development Center (Complife Italia s.r.l.).

PARTICIPANTS

Sixty-six free-living older volunteers (aged≥65 years).

INTERVENTION

Older adults were enrolled and randomly assigned to one of two groups: the camelina group or the placebo group. Subjects consumed daily 35 g of crackers (Camelina enriched crackers or placebo ones) twice daily for 12 weeks.

MEASUREMENTS

Serum polyunsaturated fatty acid profile, inflammatory status and serum lipid panel parameters were recorded pre and post-intervention.

RESULTS

In the camelina group, alpha-linolenic acid serum concentration was significantly higher (p<0.01) compared to the placebo group at the end of the study. Concerning inflammatory plasma markers, a significant mean pro-inflammatory interleukin-18 plasma concentration decrease in the placebo group compared to the camelina one was observed (p<0.05). No significant differences in other mean inflammatory markers concentrations post-intervention were noted in either group. Lastly, examining the change in lipid profile, it is noteworthy that a higher reduction of total cholesterol, low-density lipoprotein and triglycerides in the camelina group post-intervention, despite the lack of statistical significance.

CONCLUSION

Camelina oil significantly elevated the serum alpha-linolenic acid concentration with no significant changes in inflammatory markers and lipid profile.

Phenotyping congestion in patients with acutely decompensated heart failure with preserved and reduced ejection fraction: The Decongestion duRing therapY for acute decOmpensated heart failure in HFpEF vs HFrEF- DRY-OFF study

AIMS

To evaluate pulmonary and intravascular congestion at admission and repeatedly during hospitalization for acute decompensated heart failure (ADHF) in HFrEF and HFpEF patients using lung (LUS) and inferior vena cava (IVC) ultrasound.

METHODS AND RESULTS

Three-hundred-fourteen patients (82±9 years; HFpEF =172; HFrEF=142) admitted to Internal Medicine wards for ADHF were enrolled in a multi-center prospective study. At admission HFrEF presented higher indexes of pulmonary and intravascular congestion (LUS-score: 0.9 ± 0.4 vs 0.7 ± 0.4; p<0.01; IVC end-expiratory diameter: 21.6 ± 5.1 mm vs 20±5.5 mm, p<0.01; IVC collapsibility index 24.4 ± 17.4% vs 30.9 ± 21.1% p<0.01) and higher Nt-proBNP values (8010 vs 3900 ng/l; p<0.001). At discharge, HFrEF still presented higher B-scores (0.4 ± 4 vs 0.3 ± 0.4; p = 0.023), while intravascular congestion improved to a greater extent, thus IVC measurements were similar in the two groups. No differences in diuretic doses, urine output, hemoconcentration, worsening renal function were found. At 90-days follow up HF readmission/death did not differ in HFpEF and HFrEF (28% vs 31%, p = 0,48). Residual congestion was associated with HF readmission/death considering the whole population; while intravascular congestion predicted readmission/death in the HFrEF, no association between sonographic indexes and the outcome was found in HFpEF.

CONCLUSIONS

Serial assessment of pulmonary and intravascular congestion revealed a higher burden of fluid overload in HFrEF and, conversely, a greater reduction in intravascular venous congestion with diuretic treatment. Although other factors beyond EF could play a role in congestion/decongestion patterns, our data may be relevant for further phenotyping HF patients, considering the importance of decongestion optimization in the clinical approach.

A pandemic-enabled comparison of discovery platforms demonstrates a naïve antibody library can match the best immune-sourced antibodies

As a result of the SARS-CoV-2 pandemic numerous scientific groups have generated antibodies against a single target: the CoV-2 spike antigen. This has provided an unprecedented opportunity to compare the efficacy of different methods and the specificities and qualities of the antibodies generated by those methods. Generally, the most potent neutralizing antibodies have been generated from convalescent patients and immunized animals, with non-immune phage libraries usually yielding significantly less potent antibodies. Here, we show that it is possible to generate ultra-potent (IC₅₀ < 2 ng/ml) human neutralizing antibodies directly from a unique semisynthetic naïve antibody library format with affinities, developability properties and neutralization activities comparable to the best from hyperimmune sources. This demonstrates that appropriately designed and constructed naïve antibody libraries can effectively compete with immunization to directly provide therapeutic antibodies against a viral pathogen, without the need for immune sources or downstream optimization.

The most potent neutralizing antibodies are typically generated from convalescent patients and immunized animals. Here, the authors show it is possible to generate highly potent human neutralizing antibodies against the SARS-CoV-2 spike protein directly from a semisynthetic naïve antibody library.

Pandemic's silver lining

The intense international focus on the COVID-19 pandemic has provided a unique opportunity to use a wide array of novel tools to carry out scientific studies on the SARS-CoV-2 virus. The value of these comparative studies extends far beyond their consequences for SARS-CoV-2, providing broad implications for health-related science. Here we specifically discuss the impacts of these comparisons on advances in vaccines, the analysis of host humoral immunity, and antibody discovery. As an extension, we also discuss potential synergies between these areas.Abbreviations: CoVIC: The Coronavirus Immunotherapeutic Consortium; EUA: Emergency Use Authorization.

Gilteritinib as treatment for extra-medullary relapse of FLT3-ITD acute myeloid leukemia FLT3-ITD, after allogeneic haematopoietic stem cell transplantation

Case of a patient with acute myeloid leukemia (AML) positive for mutations in both genes NPM1 and FLT3-ITD who underwent two allogeneic haematopoietic stem cell transplants (HSCT); the second allograft one was followed by extramedullary relapse (granulocytic sarcoma of right breast), with blast cells positive for FLT3-ITDmutation.  Treatment with Gilteritinib, a second generation selective oral type I FLT3 inhibitor, was started after the second HSCT with complete regression of breast granulocytic sarcoma in absence of hematological and extra hematologic toxicity. We conclude that Gilteritinib can represent an effective therapy for extra hematologic relapse, with acceptable toxicity and outpatient management.

Simultaneous affinity maturation and developability enhancement using natural liability-free CDRs

Affinity maturation is often a necessary step for the development of potent therapeutic molecules. Many different diversification strategies have been used for antibody affinity maturation, including error-prone PCR, chain shuffling, and targeted complementary-determining region (CDR) mutation. Although effective, they can negatively impact antibody stability or alter epitope recognition. Moreover, they do not address the presence of sequence liabilities, such as glycosylation, asparagine deamidation, aspartate isomerization, aggregation motifs, and others. Such liabilities, if present or inadvertently introduced, can potentially create the need for new rounds of engineering, or even abolish the value of the antibody as a therapeutic molecule. Here, we demonstrate a sequence agnostic method to improve antibody affinities, while simultaneously eliminating sequence liabilities and retaining the same epitope binding as the parental antibody. This was carried out using a defined collection of natural CDRs as the diversity source, purged of sequence liabilities, and matched to the antibody germline gene family. These CDRs were inserted into the lead molecule in one or two sites at a time (LCDR1-2, LCDR3, HCDR1-2) while retaining the HCDR3 and framework regions unchanged. The final analysis of 92 clones revealed 81 unique variants, with each of 24 tested variants having the same epitope specificity as the parental molecule. Of these, the average affinity improved by over 100 times (to 96 pM), and the best affinity improvement was 231-fold (to 32 pM).

Prognostic role of echocardiography to predict cardiovascular involvement in systemic sclerosis

Funding Acknowledgements

Type of funding sources: None.

Purpose. Cardiovascular involvement in systemic sclerosis (SSc) is frequent, often subtle, and is associated with poor prognosis. Our aim was to compare echocardiographic data of SSc patients to controls, and to assess parameters able to predict the development of cardiovascular involvement.

Methods. We enrolled 756 SSc patients  (Group 1) without a previous diagnosis of cardiac involvement nor pulmonary arterial hypertension (PAH), and 614 healthy controls (Group 2) matched for age (Group 1 54.9 ± 14.6 years vs Group 2 54.4 ± 12.1, p = 0.6), sex (7.3% vs 7.2%, p = 0.8), and prevalence of hypertension (17.8% vs 19.8%, p = 0.2). All subjects underwent a comprehensive transthoracic 2D and Doppler echocardiography, including tissue Doppler imaging analysis (TDI). Five hundred and two SSc patients were followed-up and the development of PAH, left-sided heart failure (LHF), right-sided heart failure (RHF), and need of implantable cardioverter defibrillator (ICD) were considered as events.

Results. Compared to controls, SSc patients showed worse left and right ventricular systolic and diastolic function, hemodynamics and right ventricle-arterial coupling (tricuspid annulus plane systolic excursion over systolic pulmonary artery pressure, TAPSE/sPAP) (Table).  After a median follow-up with of 35 moths, 45 composite events (PAH, LVH, RHF and ICD) occurred. In a multivariate model, only ejectioin fraction (EF) and TAPSE/sPAP had independent prognostic value (Table).

Conclusions. SSc patients without overt cardiovascular involvement and no PAH display subtle impairments in biventricular systo-diastolic function and right ventricle-arterial coupling. Left ventricular EF and TAPSE/sPAP can predict further cardiovascular events.

Descriptive analysis and Cox regression Descriptive Univariate Multivariate VARIABLE Group 1 (Ssc) n = 756 Group 2 (controls) n = 614 p HR (95 % CI) p HR (95% CI) p Ejection fraction (%) 63 ± 5.7 63.7 ± 5.9 0.038 0.94 (0.88 - 0.99) 0.024 0.91 (0.85 - 0.98) 0.017 E/A 1.0 ± 0.46 1.2 ± 0.51 &lt;0.0001 1.41 (0.77 - 2.58) 0.26 e’ mean (mm) 10.7 ± 3 11.2 ± 3.4 0.034 0.87 (0.76 - 0.99) 0.038 1.0 (0.87 - 1.17) 0.902 Left atrial volume index (mL/m2) 26.5 ± 7.7 21.3 ± 6.7 &lt;0.0001 1.03 (0.98 - 1.1) 0.24 TAPSE (mm) 22.1± 23.3± &lt;0.0001 0.89 (0.81 - 0.97) 0.012 sPAP (mmHg) 24.7± 22.3± &lt;0.0001 1.07 (1.04 - 1.1) &lt; 0.0001 TAPSE/sPAP (mm/mmHg) 0.98 ± 0.96 1.1 ± 0.39 &lt;0.0001 0.036 (0.009 - 0.141) &lt; 0.0001 0.03 (0.004 - 0.19) &lt; 0.0001 Pericardial effusion 57 (7.5%) 0 (0%) &lt;0.0001 1.10 (0.38 - 3.15 ) 0.85

Pharmacological approach for the reduction of inflammatory and prothrombotic hyperactive state in COVID-19 positive patients by acting on complement cascade

The novel Coronavirus SARS-CoV-2 is the viral pathogen responsible for the ongoing global pandemic, COVID-19 (Coronavirus disease 2019). To date, the data recorded indicate 1.62 Mln deaths and 72.8 Mln people infected (WHO situation report Dec 2020). On December 27, the first anti-COVID-19 vaccinations started in Europe. There are no direct antivirals against SARS-CoV-2. Understanding the pathophysiological and inflammatory/immunological processes of SARS-CoV-2 infection is essential to identify new drug therapies. In the most severe COVID-19 cases, an unregulated immunological/inflammatory system results in organ injury that can be fatal to the host in some cases. Pharmacologic approaches to normalize the unregulated inflammatory/immunologic response is an important therapeutic solution. Evidence associates a non-regulation of the “complement system” as one of the causes of generalized inflammation causing multi-organ dysfunction. Serum levels of a complement cascade mediator, factor “C5a”, have been found in high concentrations in the blood of COVID-19 patients with severe disease. In this article we discuss the correlation between complement system and COVID-19 infection and pharmacological solutions directed to regulate.

Exploiting next-generation sequencing in antibody selections - a simple PCR method to recover binders

Antibody discovery using invitro display technologies such as phage and/or yeast display has become acornerstone in many research and development projects, including the creation of new drugs for clinical use. Traditionally, after the selection phase, random clones are isolated for binding validation and Sanger sequencing. More recently, next-generation sequencing (NGS) technology has allowed deeper insight into the antibody population after aselection campaign, enabling the identification of many more specific binders. However, this approach only provides the DNA sequences of potential binders, the properties of which need to be fully elucidated by obtaining corresponding clones and expressing them for further validation. Here we present arapid novel method to harvest potential clones identified by NGS that uses asimple PCR and yeast recombination approach. The protocol was tested in selections against three different targets and was able to recover clones at an abundance level that would be impractical to identify using traditional methods.

Drug-like antibodies with high affinity, diversity and developability directly from next-generation antibody libraries

Therapeutic antibodies must have "drug-like" properties. These include high affinity and specificity for the intended target, biological activity, and additional characteristics now known as "developability properties": long-term stability and resistance to aggregation when in solution, thermodynamic stability to prevent unfolding, high expression yields to facilitate manufacturing, low self-interaction, among others. Sequence-based liabilities may affect one or more of these characteristics. Improving the stability and developability of a lead antibody is typically achieved by modifying its sequence, a time-consuming process that often results in reduced affinity. Here we present a new antibody library format that yields high-affinity binders with drug-like developability properties directly from initial selections, reducing the need for further engineering or affinity maturation. The innovative semi-synthetic design involves grafting natural complementarity-determining regions (CDRs) from human antibodies into scaffolds based on well-behaved clinical antibodies. HCDR3s were amplified directly from B cells, while the remaining CDRs, from which all sequence liabilities had been purged, were replicated from a large next-generation sequencing dataset. By combining two in vitro display techniques, phage and yeast display, we were able to routinely recover a large number of unique, highly developable antibodies against clinically relevant targets with affinities in the subnanomolar to low nanomolar range. We anticipate that the designs and approaches presented here will accelerate the drug development process by reducing the failure rate of leads due to poor antibody affinities and developability.Abbreviations: AC-SINS: affinity-capture self-interaction nanoparticle spectroscopy; CDR: complementarity-determining region; CQA: critical quality attribute; ELISA: enzyme-linked immunoassay; FACS: fluorescence-activated cell sorting; Fv: fragment variable; GM-CSF: granulocyte-macrophage colony-stimulating factor; HCDR3: heavy chain CDR3; IFN2a: interferon α-2; IL6: interleukin-6; MACS: magnetic-activated cell sorting; NGS: next generation sequencing; PCR: polymerase chain reaction; SEC: size-exclusion chromatography; SPR: surface plasmon resonance; TGFβ-R2: transforming growth factor β-R2; VH: variable heavy; VK: variable kappa; VL: variable light; Vl: variable lambda.

The Influence of Medial Comminution in the Treatment Choice of Radial Head Fracture

Introduction:

The aim of our retrospective study was to investigate the role of the medial side involvement in the treatment choice of radial head fractures.

Materials and Methods:

We searched the databases of our institutions for the surgical procedures diagnosed as "fracture of the radial head" and for the procedures related to "prosthesis of the radial head" and "osteosynthesis of the radial head" in the period from May 2014 to October 2017. The fractures were first classified according to the Mason classification . We then allocated the patients into three study groups according to the site of the fracture, either the medial or lateral side of the radial head : Group A, with an isolated lateral fracture of the radius head; Group B1, with a medial fracture of the radius head with two medial fragments; and Group B2, with a medial fracture of the radius head with multiple medial fragments. We performed a multivariate analysis to identify statistically significant correlation between the pre-operative classifications of Mason and our study, the type of surgical procedure, and the clinical outcome.

Results:

Mayo Elbow Performance (MEP) scores determined at the final follow-up of the study (mean 16.6 months, range 12-26 months) was excellent in 17 patients (4 in Group A, 6 in Group B1 and 7 in Group B2), and good in 12 patients (3 in Group A, 7 in Group B1, and 2 in Group B2). One patient showed a poor result in MEP score probably because of an infection and implant removal.

Conclusion:

Regarding medial fractures of the radial head, our study showed satisfactory results with a radial head prosthesis for comminuted or multifragmentary radial head fractures. For surgeons with advanced elbow fracture expertise, osteosynthesis could be attempted in a fracture pattern that involved only two medial fragments.

KRD (carfilzomib and lenalidomide plus dexamethasone) for the treatment of relapsed or refractory multiple myeloma in the real-life: a retrospective survey in 123 patients

From April 2016, carfilzomib, in combination with lenalidomide and dexamethasone (KRD), became available for use in the daily practice in Italy for patients with relapsed or refractory multiple myeloma (RRMM). We performed a retrospective survey at 14 different institutions from Southern Italy in order to evaluate patient characteristics and treatment results from an unselected series of patients treated accordingly so far. One hundred and twenty-three consecutive patients were included, with a median of 2 previous lines of therapy (range 1-9) and a median age of 63 years (range 39-82). At the time of analysis, median number of courses administered is 11 (range 1-34), and all patients are evaluable for response. Overall response rate including complete remission, very good partial remission, and partial remission is 85%. After a median follow-up of 27 months, median overall and progression-free survival are 33 and 23 months, respectively. Sixty-three patients are alive and between them, 45 (37%) are in continuous remission. Sixty patients have died (49%), mainly from progressive disease. There were 6 treatment-related deaths (5% of the whole patient population). Overall, hematological and non-hematological toxicity were manageable, mostly on outpatient basis. Arterial hypertension has been observed in 43 cases (35%) but did not lead to treatment interruption. Our data demonstrate that in real life, KRD is highly effective and well tolerated in the majority of patients with RRMM.

P944 From systolic pulmonary arterial pressure to pulmonary vascular resistance and reserve: a simplified method for exercise stress echocardiography

OnBehalf

On behalf of Stress Echo 2020 study group of the Italian Society of Echocardiography and Cardiovascular Imaging (SIECVI).

Background

The potential of exercise stress echocardiography (ESE) seems to be still underused especialy in the assessment of pulmonary hemodynamics.

Aim

To assess the feasibility and compare pulmonary vascular resistance (PVResistance) and reserve (PVReserve) during ESE in patients at risk of pulmonary hypertension (PH) and controls.

Methods

We performed semi-supine ESE, in 97 subjects (age 49 ± 16 yrs, 63 females): 58 patients (Group 1) at risk for PH (systemic sclerosis and other connective tissue diseases) and 39 healthy controls (Group 2). Rest and stress assessment included: tricuspid regurgitant velocity (TRV), pulmonary acceleration time (ACT), cardiac output (CO), SPAP estimation with Bernouilli equation or from ACT with formula: log10 SPAP= - 0.004 (ACT) + 2.1. We estimated PVResistance from Abbas formula, and PVReserve as ΔCO/ ΔSPAP or (when CO was not available) as minutes of exercise/ΔSPAP. When ΔSPAP was &lt;10 mmHg, it was considered equal to 1.

Results

With TRV or ACT to estimate pressures, and cardiac output or its proxy to estimate flow, PVResistance or PVReserve could be measured in all patients. At peak exercise, PVResistance was higher and PVReserve lower in Group 1 : see Table.

Conclusion

Estimation of PVResistance and/or PVReserve can be obtained in all patients during ESE, integrating TRV with ACT, and using exercise-time as a proxy of CO when the latter is not available. These indices may be useful for a better, noninvasive characterization of the heterogeneity of pulmonary hemodynamics.

Pulmonary hemodynamics ESE data Parameter Group 1, PH (n = 58) Group 2, normals (n = 39) P value TRV rest (cm/s) 243 ± 63 204 ± 31 =0.0147 TRV peak (cm/s) 344 ± 68 204 ± 53 &lt;0.0001 ACT rest (ms) 113 ± 33 128 ± 20 =0.0205 ACT peak (ms) 86 ± 19 94 ± 22 ns SPAP rest (mm Hg) 26 ± 10 21 ± 4 =0.0039 SPAP peak (mm Hg) 45 ± 19 28 ± 13 &lt;0.0001 CO rest (mL/min) 4.9 ± 1.7 5.1 ± 1.7 ns CO peak (mL/min) 7.8 ± 2.8 7.6 ± 2.9 ns Exercise time (min) 7 ± 2 13 ± 3 &lt;0.0001 PVResistance (WU) rest 1.63 ± 0.52 1.54 ± 0.34 ns PVResistance (WU) peak 2.01 ± 0.89 1.27 ± 0.42 =0.0219 PVReserve (ΔCO/ΔSPAP) 1.38 ± 1.13 3.55 ± 2.45 =0.001 PVReserve (Extime/ΔSPAP) 4.69 ± 2.67 10.96 ± 4.39 &lt;0.0001 Legends: WU -Wood Unit, Ex time - exercise time

P737 Left ventricular hemodynamic forces: towards establishing reference values for healthy adults

Introduction

Left ventricular hemodynamic forces (LV-HDF) have been recently demonstrated to be promising markers of sub-clinical dysfunction and potential predictors of disease outcome. However, there is a lack of reference values in healthy subjects. Knowledge of physiologic ranges is mandatory towards the use of LV-HDF-based indices for disease assessment in future clinical applications.

Purpose

Aim of the current study is to define the normal reference values for LV-HDF parameters in a large cohort of healthy adults. Here we present preliminary results for the initial set of enrolled subjects.

Methods

We enrolled 82 healthy subjects [mean age 44 ± 13.2 years (range 18-88), 41 men]. All participants underwent standard transthoracic echocardiography (TTE) examination, as recommended by current guidelines, including apical two-, three- and four-chamber windows, acquired at a frame rate above 40 Hz. These were then analyzed by tri-plane tissue tracking, measuring LV volume and LV ejection fraction (EF) as reference parameters. The same tracking method was used to evaluate the global hemodynamic force by a novel mathematical calculation technique applied to the three-dimensional endocardial contour. Physical-based LV-HDF parameters were then extracted for clinical application; these included the amplitude (root mean square) of the longitudinal and transversal force components (FL and FT) and their alignment angle relative to the LV axis. Parameters were computed as average over the whole cardiac cycle as well as limited to the systolic phase. Forces were normalized with LV volume to reduce variability with LV dimension, and divided by specific weight to yield a dimensionless measure.

Results

Mean EF was 63 ± 9%. Whole cycle LV-HDF parameters were: FL = 16.0 ± 5.6%, FT = 2.3 ± 0.8%, with significant longitudinal alignment FT/FL = 0.15 ± 0.04, angle = 13.0°±3.1°. Systolic HDF parameters were: FL = 22.7 ± 8.2%, FT = 2.9 ± 1.1%, with longitudinal alignment FT/FL = 0.13 ± 0.04, angle = 11.2°±3.1°. Importantly, dimensionless physical-based LV-HDF parameters showed no significant variation with age, gender or BSA.

Conclusions

We report the physiologic range of LV-HDF parameters measured by TTE. Knowledge of age- and gender-specific reference values, for a combination of standard, mechanical and hemodynamic indices, can improve the global assessment of the LV function and may help to detect sub-clinical stages of LV dysfunction.

P1449 CMR-driven computational modeling of right ventricular flow dynamics

Introduction

The analysis of intracardiac blood flow patterns can significantly contribute to improve the understanding and treatment of cardiovascular disease. In contrast to the substantial literature on the left side of the heart, there is currently a significant lack of knowledge about the fluid mechanics of the right heart – pulmonary circulation unit (RH-PCU), both in healthy and diseased conditions.

Purpose

It is conjectured that computational modeling can be a key element to enhance current imaging techniques and provide quantitative insights into the unique RH-PCU biomechanics. Here we present a novel methodology that allows personalized numerical simulations of right heart flows, through a proper combination of cardiac magnetic resonance (CMR) with computational fluid dynamics (CFD).

Methods and results

We developed a patient-specific pipeline from medical images to computational models, as depicted in the figure. First, the RV geometry is reconstructed from time-resolved CMR cine images, comprising short-axis and longitudinal slices of the heart, where feature-tracking techniques are used to extract the motion of the RV endocardium contours. A time-continuous description of the moving geometry is obtained through an image-registration algorithm based on diffeomorphic mappings. The moving model of the RV, including the outflow tract and proximal pulmonary arteries, is finally fed to a dedicated CFD solver. The tool is able to provide a detailed description of the velocity and pressure fields inside the right ventricle and proximal pulmonary arteries during all phases of the cardiac cycle. From these fields, global hemodynamic quantities such as vortex properties, kinetic energy, pressure gradients and hemodynamic forces can be computed.

Conclusions

CMR-driven computational modeling of intra-ventricular flow enables a promising approach for understanding and evaluating the biomechanical environment of the right heart. This high-fidelity framework can be applied to investigate the RV response and adaptation to abnormal pressure and/or volume load conditions. It can also be used to reproduce the virtual flow that would realize in hypothetical conditions, and therefore adds predictive capabilities to modern flow imaging. The analysis may allow to determine an association between blood flow patterns and disease progression, and ultimately lead to derive and validate imaging biomarkers of clinical significance.

Abstract P1449 Figure. Pipeline for patient-specific modeling

1682 Feasibility of the exercise stress echocardiography for the evaluation of the right heart and pulmonary circulation unit in different clinical conditions: the right heart international network

Funding Acknowledgements

no funding sources exists

OnBehalf

RIGHT Heart International NETwork (RIGHT-NET)

Purpose

Exercise stress echocardiography (ESE) is a well-validated tool in ischemic and valvular heart diseases. The aim of this study is to assess the ESE feasibility for the evaluation of the right heart pulmonary circulation unit (RH-PCU) in a large cohort of subjects, from healthy individuals and elite athletes to patients with overt or at risk of developing pulmonary hypertension. Methods: 954 subjects [mean age 54.2 ± 16.4 years, 430 women] [254 healthy volunteers, 40 elite athletes, 363 patients with cardiovascular risk factors, 25 with pulmonary arterial hypertension, 149 with connective tissue diseases, 81 with left heart and valvular diseases, 42 with lung diseases], underwent standardized semi-recumbent cycle ergometer ESE with an incremental workload of 25 watts every 2 minutes up to symptom-limited maximal tolerated workload. ESE parameters of right heart structure, function and pressures were obtained according current recommendations. Results: The success rate for the evaluation of the RV function at peak exercise was 903/940 (96%) for tricuspid annular plane systolic excursion (TAPSE), 667/751 (89%) for tissue Doppler–derived tricuspid lateral annular systolic velocity (S’) and 425/772 (63%) for right ventricular fractional area change (RVFAC). Right ventricular–right atrial pressure gradient [RV-RA gradient = 4 x tricuspid regurgitation velocity2] was obtained in 894/954 patients (93.7 %) at rest and in 816/954 (85.5%) at peak exercise. At peak exercise, pulmonary acceleration time (AcT) was feasible among 435/545 (82.5%) patients (Table 1). Conclusions: In daily ESE monitoring of TAPSE and S’ resulted to be less challenging than of RV FAC. ESE was a feasible tool for the evaluation of RV-RA gradient and pulmonary AcT.

Table 1 Parameters Rest mean ± SD Peak mean ± SD P value Assessed n (%) Feasibility at rest n (%) Feasibility at peak n (%) RVED area (cm2) 17.4 ± 5.7 17.4 ± 5.8 0.9 672 632 (94.0) 425 (63.2) RVES area (cm2) 9.7 ± 4.3 9.6 ± 4.9 0.7 672 632 (94.0) 425 (63.2) TAPSE (mm) 22.9 ± 3.9 27.4 ± 5.5 &lt;0.001 940 922 (98.1) 903 (96.0) S’(cm/s) 13.1 ± 2.9 18.5 ± 5.0 &lt;0.001 751 746 (99.4) 667 (88.8) RVFAC (%) 45.7 ± 10 46.7 ± 11 0.121 672 632 (94.0) 425 (63.2) RV-RA gradient (mmHg) 24.3 ± 15 42.5 ± 20 &lt;0.001 954 894 (93.7) 816 (85.5) Pulmonary AcT (m/s) 129 ± 31 116 ± 35 &lt;0.001 545 527( 96.7) 435 (82.5) RVED, right ventricle end diastolic area; RVES, right ventricle end systolic area; p values indicate differences at rest and peak exercise. The term “assessed” indicates that an attempt was done in order to measure the parameter. The term “feasibility” indicates that it was possible to measure the parameter that was assessed.

P1711 Exploring the full spectrum of right ventricular exercise contractile reserve among health and disease: a prospective clinical and echocardiography observational multicenter study

Funding Acknowledgements

None

OnBehalf

RIGHT-NET

Background

Exercise Doppler echocardiography (EDE) has been implemented for applications beyond coronary artery disease detection, but its role in assessing subclinical pulmonary vascular disease and right ventricle (RV) impairment is less clear. The RIGHT heart international NETwork (RIGHT-NET) is a prospective clinical and echocardiography observational multicenter study designed to explore the full spectrum of RV function and non-invasive pulmonary circulation hemodynamics during exercise in a large cohort of subjects, from healthy individuals and elite athletes to patients with overt or at risk of developing pulmonary hypertension (PH). Right ventricular (RV) exercise contractile reserve (RVECR) can be assessed through the ratio between tricuspid annular plane systolic excursion (TAPSE) and systolic pulmonary artery pressure (sPAP) and has proved to provide prognostic value in patients with left heart disease (LHD) and pulmonary arterial hypertension (PAH).

Methods

We enrolled 1424 patients (age 55.4 ± 15 years old, 44.4% males): 353 healthy controls, 40 athletes, 369 patients with cardiovascular risk factors (CVRF: arterial hypertension and/or diabetes mellitus), 46 with PAH (confirmed by right heart catheterization), 487 with systemic sclerosis (SSc) without overt PH, and 129 with LHD (including coronary artery disease and heart failure with reduced or preserved ejection fraction).

All enrolled subjects underwent resting and EDE examinations on a semirecumbent cycle ergometer with an incremental workload of 25 Watts every 2 minutes up to the symptom-limited maximal tolerated workload, according to standardised protocols. Key echocardiographic measurements have been acquired at baseline, at 50 Watts, at peak exercise, and after 5-minutes recovery, including but not limited to RV function (TAPSE) and sPAP.

Results

In all six groups the ratio TAPSE/sPAP was significantly different at peak exercise compared to rest values (all p &lt; 0.01). At rest, TAPSE/sPAP values were not significantly different among controls, athletes and CVRF patients, whereas during exercise TAPSE/sPAP values were significantly different, with CVRF showing the lowest values (p &lt; 0.0001 vs controls and athletes). Patients with PAH and LHD had the worst RVECR both at rest and at peak exercise (all p &lt; 0.0001 vs the other groups), while SSc groups reported intermediate values, which were lower than controls (p &lt; 0.0001) and athletes (p &lt; 0.0001), but higher than CVRF subjects (p = 0.003). (Figure)

Conclusions

EDE can non-invasively characterise different dynamic behaviours of the RVECR among healthy subjects, athletes and patients with various pathologic conditions. Whether a thorough EDE assessment of non-invasive hemodynamics, RVECR and coupling may predict later development of manifest PH, clinical deterioration or decreased survival will be further investigated during the ongoing follow-up.

Abstract P1711 Figure

A Functional Idiotype/Anti-Idiotype Network Is Active in Genetically Gluten-Intolerant Individuals Negative for Both Celiac Disease-Related Intestinal Damage and Serum Autoantibodies

An unbalance between Abs that recognize an autoantigen (idiotypes; IDs) and Igs that bind such Abs (anti-IDs) is considered a functional event in autoimmune disorders. We investigated the presence of an ID/anti-ID network in celiac disease (CD), a condition in which antitissue transglutaminase 2 (TG2) Abs are suspected to contribute to CD pathogenesis. To characterize the ID side, we reproduced by in vitro yeast display the intestine-resident Abs from CD and control patients. These TG2-specific IDs were used to identify potential anti-IDs in the serum. We observed elevated titers of anti-IDs in asymptomatic patients with predisposition to CD and demonstrated that anti-ID depletion from the serum restores a detectable humoral response against TG2. Our study provides an alternative approach to quantify CD-related autoantibodies in cases that would be defined "negative serology" with current diagnostic applications. Therefore, we suggest that developments of this technology could be designed for perspective routine tests.

Elderly psoriatic patients under biological therapies: an Italian experience

BACKGROUND

The number of elderly patients with psoriasis is steadily increasing in the Western world; nevertheless, they are frequently excluded from biological clinical trials and described as a high-risk group for adverse events. Thus, there is lack of information concerning safety and effectiveness of available treatments for psoriasis in the elderly, particularly about new biological systemic drugs.

OBJECTIVE

Our aim was to describe our experience with all biological therapies currently used in the elderly (>65 years) psoriatic patients.

METHODS

A retrospective multicentric review of clinical records of all psoriatic patient aged 65 years or older actually receiving biological drugs (etanercept, adalimumab, infliximab, golimumab, certolizumab pegol, ustekinumab or secukinumab) was undertaken.

RESULTS

Our study population included 266 elderly psoriatic patients actually receiving any biological therapy (adalimumab 31.2%, ustekinumab 28.9%, etanercept 20.3%, secukinumab 15%, infliximab 3%, golimumab 1% and certolizumab pegol 0.6%). The PASI score at the baseline (week 0) ranged from 4 to 54; mean ± SD, 16.5 ± 7.1, which changed after biological administration to 3.7 ± 8 at week 16, 1.6 ± 2.1 at week 28 and 1.2 ± 2.1 at week 52. Among 266 elderly psoriatic patients, 25 adverse events were reported during the observation period. The most frequent events were infections with 12 (48%) reports, followed by malignancies with four (16%) reports.

CONCLUSIONS

To date, our study represents the widest experience on the use of biological drugs in elderly psoriatic patients. We found that all biologics for psoriasis showed a great efficacy also in elderly people, and the rate and the type of adverse effects were similar to the younger patients. In conclusion, the age alone should not limit our therapeutic options. Further observational study using multiple data sources is needed to evaluate long-term effectiveness and safety for elderly psoriatic patients.

Rapid purification of billions of circulating CD19+ B cells directly from leukophoresis samples

The study of the biology and function of B cells, or the dissection and in vitro creation of enormous recombinant antibody repertoires, requires the isolation of large numbers of pure CD19+ B cells. The StraightFrom^® Leukopak CD19 MicroBead Kit was recently introduced as a fast and robust kit to isolate human CD19+ B cells. This uses paramagnetic microbeads conjugated to high-affinity anti-CD19 monoclonal antibodies to bind B cells in leukapheresis (Leukopak) samples. The overall purity of the isolated cells, together with the characterization of the different CD19+ subclasses, was assessed by flow cytometry using a recombinant (REAffinity) antibody panel, revealing that the method allowed the recovery of over 93% of CD19+ B cells without any pre-purification step. This enables the relatively straightforward purification of all the circulating CD19+ B cells in a single donor.

Selection of phage-displayed accessible recombinant targeted antibodies (SPARTA): methodology and applications

We developed a potentially novel and robust antibody discovery methodology, termed selection of phage-displayed accessible recombinant targeted antibodies (SPARTA). This combines an in vitro screening step of a naive human antibody library against known tumor targets, with in vivo selections based on tumor-homing capabilities of a preenriched antibody pool. This unique approach overcomes several rate-limiting challenges to generate human antibodies amenable to rapid translation into medical applications. As a proof of concept, we evaluated SPARTA on 2 well-established tumor cell surface targets, EphA5 and GRP78. We evaluated antibodies that showed tumor-targeting selectivity as a representative panel of antibody-drug conjugates (ADCs) and were highly efficacious. Our results validate a discovery platform to identify and validate monoclonal antibodies with favorable tumor-targeting attributes. This approach may also extend to other diseases with known cell surface targets and affected tissues easily isolated for in vivo selection.

When monoclonal antibodies are not monospecific: Hybridomas frequently express additional functional variable regions

Monoclonal antibodies are commonly assumed to be monospecific, but anecdotal studies have reported genetic diversity in antibody heavy chain and light chain genes found within individual hybridomas. As the prevalence of such diversity has never been explored, we analyzed 185 random hybridomas, in a large multicenter dataset. The hybridomas analyzed were not biased towards those with cloning difficulties or known to have additional chains. Of the hybridomas we evaluated, 126 (68.1%) contained no additional productive chains, while the remaining 59 (31.9%) contained one or more additional productive heavy or light chains. The expression of additional chains degraded properties of the antibodies, including specificity, binding signal and/or signal-to-noise ratio, as determined by enzyme-linked immunosorbent assay and immunohistochemistry. The most abundant mRNA transcripts found in a hybridoma cell line did not necessarily encode the antibody chains providing the correct specificity. Consequently, when cloning antibody genes, functional validation of all possible VH and VL combinations is required to identify those with the highest affinity and lowest cross-reactivity. These findings, reflecting the current state of hybridomas used in research, reiterate the importance of using sequence-defined recombinant antibodies for research or diagnostic use.

Many Routes to an Antibody Heavy-Chain CDR3: Necessary, Yet Insufficient, for Specific Binding

Because of its great potential for diversity, the immunoglobulin heavy-chain complementarity-determining region 3 (HCDR3) is taken as an antibody molecule’s most important component in conferring binding activity and specificity. For this reason, HCDR3s have been used as unique identifiers to investigate adaptive immune responses in vivo and to characterize in vitro selection outputs where display systems were employed. Here, we show that many different HCDR3s can be identified within a target-specific antibody population after in vitro selection. For each identified HCDR3, a number of different antibodies bearing differences elsewhere can be found. In such selected populations, all antibodies with the same HCDR3 recognize the target, albeit at different affinities. In contrast, within unselected populations, the majority of antibodies with the same HCDR3 sequence do not bind the target. In one HCDR3 examined in depth, all target-specific antibodies were derived from the same VDJ rearrangement, while non-binding antibodies with the same HCDR3 were derived from many different V and D gene rearrangements. Careful examination of previously published in vivo datasets reveals that HCDR3s shared between, and within, different individuals can also originate from rearrangements of different V and D genes, with up to 26 different rearrangements yielding the same identical HCDR3 sequence. On the basis of these observations, we conclude that the same HCDR3 can be generated by many different rearrangements, but that specific target binding is an outcome of unique rearrangements and VL pairing: the HCDR3 is necessary, albeit insufficient, for specific antibody binding.

Therapeutic targeting of membrane-associated GRP78 in leukemia and lymphoma: preclinical efficacy in vitro and formal toxicity study of BMTP-78 in rodents and primates

Translation of drug candidates into clinical settings requires demonstration of preclinical efficacy and formal toxicology analysis for filling an Investigational New Drug (IND) application with the US Food and Drug Administration (FDA). Here, we investigate the membrane-associated glucose response protein 78 (GRP78) as a therapeutic target in leukemia and lymphoma. We evaluated the efficacy of the GRP78-targeted proapoptotic drug bone metastasis targeting peptidomimetic 78 (BMTP-78), a member of the D(KLAKLAK)2-containing class of agents. BMTP-78 was validated in cells from patients with acute myeloid leukemia and in a panel of human leukemia and lymphoma cell lines, where it induced dose-dependent cytotoxicity in all samples tested. Based on the in vitro efficacy of BMTP-78, we performed formal good laboratory practice toxicology studies in both rodents (mice and rats) and nonhuman primates (cynomolgus and rhesus monkeys). These analyses represent required steps towards an IND application of BMTP-78 for theranostic first-in-human clinical trials.

Imaging-Guided Preoperative Localization of Intra-Abdominal Local Recurrences of Colorectal Cancer Using the Harpoon Technique

BACKGROUND AND AIMS

Intra-abdominal local recurrences of colorectal cancer can be difficult to localize and excise because they are not easily visible or palpable.

MATERIALS AND METHODS

We report on our experience using the computed tomography-guided harpoon technique to locate and resect these nodules in seven patients.

RESULTS

No complications were recorded during the procedures. Six nodes were malignant and all margins were tumor free.

CONCLUSIONS

Harpoon placement for intra-abdominal local recurrences of colorectal cancer is a feasible and useful technique that provides direct localization and complete excision of lesions.

Production of human pro-relaxin H2 in the yeast Pichia pastoris

Background

Initially known as the reproductive hormone, relaxin was shown to possess other therapeutically useful properties that include extracellular matrix remodeling, anti-inflammatory, anti-ischemic and angiogenic effects. All these findings make relaxin a potential drug for diverse medical applications. Its precursor, pro-relaxin, is an 18 kDa protein, that shows activity in in vitro assays. Since extraction of relaxin from animal tissues raises several issues, prokaryotes and eukaryotes were both used as expression systems for recombinant relaxin production. Most productive results were obtained when using Escherichia coli as a host for human relaxin expression. However, in such host, relaxin precipitated in the form of inclusion bodies and, therefore, required several expensive recovery steps as cell lysis, refolding and reduction.

Results

To overcome the issues related to prokaryotic expression here we report the production and purification of secreted human pro-relaxin H2 by using the methylotrophic yeast Pichia pastoris as expression host. The methanol inducible promoter AOX1 was used to drive expression of the native and histidine tagged forms of pro-relaxin H2 in dual phase fed-batch experiments on the 22 L scale. Both protein forms presented the correct structure, as determined by mass spectrometry and western blotting analyses, and demonstrated to be biologically active in immune enzymatic assays. The presence of the tag allowed to simplify pro-relaxin purification obtaining higher purity.

Conclusions

This work presents a strategy for microbial production of recombinant human pro-relaxin H2 in Pichia pastoris that allowed the obtainment of biologically active pro-hormone, with a final concentration in the fermentation broth ranging between 10 and 14 mg/L of product, as determined by densitometric analyses.

Electronic supplementary material

The online version of this article (doi:10.1186/s12896-016-0319-0) contains supplementary material, which is available to authorized users.

Behaviour of the plasma concentration of gelatinases and their tissue inhibitors in subjects with venous leg ulcers

Venous leg ulcers are common in subjects with chronic venous insufficiency. The increased intraluminal pressure causes alteration of the skin microcirculation, leukocyte activation and release of proteolytic enzymes leading to ulceration. An impaired expression and activity of matrix metalloproteases (MMPs) and their tissue inhibitors (TIMPs) might influence extracellular matrix degradation and deposition in chronic venous ulcers with the failure of the healing process. Our aim was to evaluate plasma concentration of gelatinases (MMP-2 and MMP-9) and their inhibitors (TIMP-1 and TIMP-2) in subjects with venous leg ulcers before and after the compression therapy. We enrolled 36 subjects (12 men and 24 women, mean age 67.38 ± 12.7 yrs) with non-infected venous leg ulcers (CEAP C6), which underwent a color Duplex scan examination of the veins and arteries of the inferior limbs and were treated with a multi-layer bandaging system. The ulcer healing was obtained in 23 subjects only (9 men and 14 women). We evaluated, on fasting venous blood, the plasma levels of MMP-2, MMP-9, TIMP-1 and TIMP-2 using ELISA kit, before and after the treatment. We observed a significant increase in plasma concentration of gelatinases and their inhibitors and in MMP-2/TIMP-2 ratio in subjects with leg ulcers in comparison with normal controls. In subjects with healed ulcers we found a decrease in MMP-9 and TIMP-1 levels and in MMP-2/TIMP-2 ratio compared to the baseline values, although higher levels of all the examined parameters in comparison with normal controls. In conclusion, plasma MMPs profile is impaired in subjects with venous leg ulcers and it improves after the healing, persisting anyway altered in respect to healthy controls.

Can a biomimetic osteochondral scaffold be a reliable alternative to prosthetic surgery in treating late-stage SPONK?

BACKGROUND

This study aimed to assess the reliability of the Maioregen® biomimetic osteochondral scaffold (Finceramica Faenza SpA, Faenza, Italy) as a salvage and joint-preserving procedure in the treatment of late-stage osteonecrosis of the knee.

METHODS

Eleven active patients aged under 65years and presenting with clinical and radiological signs of SPONK were treated with Maioregen®. All were clinically evaluated pre-operatively and yearly thereafter for a minimum of two years. Subjective IKDC and Lysholm Knee Scale scores were used to assess clinical outcome. A VAS scale served to quantify pre-operative pain and post-operative pain. Activity levels were evaluated pre-operatively and at follow-up using the Tegner Activity Scale.

RESULTS

Subjective IKDC (40±15.0 to 65.7±14.8 (mean±SD)) and Lysholm Knee Scale (49.7±17.9 to 86.6±12.7 (mean±SD)) scores improved significantly from pre-operative evaluation (p<.01). VAS scores decreased from a pre-operative mean (±SD) of 6.3±2.5 to 1.6±2.7 at two years. The Tegner Activity Scale showed no significant differences between pre-injury and two-year follow-up. Two out of the 11 patients were symptomatic at 18months post implant and progressed to condylar collapse. These patients required total knee arthroplasty.

CONCLUSIONS

Use of a biomimetic scaffold can be a valid option in the surgical treatment of SPONK in relatively young active patients. Indeed, this surgical technique, originally developed for osteochondritis dissecans, has been found to give good clinical results at medium-term follow-up of late-stage osteonecrosis treatment and could postpone or even avoid the need for joint replacement procedures.

Deep sequencing in library selection projects: what insight does it bring?

High throughput sequencing is poised to change all aspects of the way antibodies and other binders are discovered and engineered. Millions of available sequence reads provide an unprecedented sampling depth able to guide the design and construction of effective, high quality naïve libraries containing tens of billions of unique molecules. Furthermore, during selections, high throughput sequencing enables quantitative tracing of enriched clones and position-specific guidance to amino acid variation under positive selection during antibody engineering. Successful application of the technologies relies on specific PCR reagent design, correct sequencing platform selection, and effective use of computational tools and statistical measures to remove error, identify antibodies, estimate diversity, and extract signatures of selection from the clone down to individual structural positions. Here we review these considerations and discuss some of the remaining challenges to the widespread adoption of the technology.