Elevated Lipoprotein(a) levels increase Major Adverse Limb Event

Background

High lipoprotein(a) levels are involved in the development of cardiovascular events, as particularly in myocardial infarction, stroke, and peripheral artery disease. Studies assessing prognostic values of lipoprotein(a) levels on the lower limbs are lacking.

Purpose

The aim of our study was to look after a relationship between the lipoprotein(a) level and the incidence of major adverse limb events (MALE) defined as major amputation, peripheral artery endovascular revascularization or peripheral artery bypass.

Methods

We included 16,513 patients with lipoprotein(a) measurements from our clinical information system. Normal lipoprotein(a) level was under 50 mg/dL and we defined: high lipoprotein(a) level as a lipoprotein(a) level between 50 mg/dL and 134 mg/dL and very high lipoprotein(a) level as a lipoprotein(a) levels over 134 mg/dL, i.e the 95th percentile in this cohort. Accelerated Failure Time models were used to assess the relationship between the lipoprotein(a) level and the incidence of MALE retrieved from the patient's electronic record during a median (interquartile range) follow-up of 3.74 (1.07; 7.30) years after the lipoprotein(a) measurement. MALE was defined as the occurrence of one of the following during follow-up: aortofemoral bypass surgery, limb bypass surgery, percutaneous transluminal angioplasty revascularization of the iliac, or infrainguinal arteries; or major amputation above the forefoot. Secondary outcomes included individual components of the primary

Results

Median lipoprotein(a) level was 24 mg/dL (10; 60), with 70.3%; 24.7%; and 5.0% within normal; high and very high lipoprotein(a) level respectively. The 1-year MALE incidence was 2.2% [95% CI: 1.96; 2.51]; 2.60% [95% CI: 2.09; 3.10] and 4.54% [95% CI: 3.08; 5.98] among the normal, high and very high lipoprotein(a) level patients respectively. High and very high lipoprotein(a) levels were independently associated with an increased risk of MALE (adjusted Accelerated Failure Time Exponential Estimate) 0.43 [95% CI: 0.24; 0.78], p=0.01 and 0.17 [95% CI: 0.07; 0.40], p<0.001, respectively.

Conclusion

In this large cohort of unselected real-world hospital inpatients, higher lipoprotein(a) levels were independently associated with an increased risk of MALE. Though, lipoprotein(a) measurement shall be taken into account not only to refine the cardiovascular risk but also the lower limb risk of revascularization or amputation.

Funding Acknowledgement

Type of funding sources: None.

The Dual Targeting of FcRn and FcγRs via Monomeric Fc Fragments Results in Strong Inhibition of IgG-Dependent Autoimmune Pathologies

Novel molecules that directly target the neonatal Fc receptor (FcRn) and/or Fc gamma receptors (FcγRs) are emerging as promising treatments for immunoglobulin G (IgG)-dependent autoimmune pathologies. Mutated Fc regions and monoclonal antibodies that target FcRn are currently in clinical development and hold promise for reducing the levels of circulating IgG. Additionally, engineered structures containing multimeric Fc regions allow the dual targeting of FcRn and FcγRs; however, their tolerance needs to first be validated in phase I clinical studies. Here, for the first time, we have developed a modified monomeric recombinant Fc optimized for binding to all FcRns and FcγRs without the drawback of possible tolerance associated with FcγR cross-linking. A rational approach using Fc engineering allowed the selection of LFBD192, an Fc with a combination of six mutations that exhibits improved binding to human FcRn and FcγR as well as mouse FcRn and FcγRIV. The potency of LFBD192 was compared with that of intravenous immunoglobulin (IVIg), an FcRn blocker (Fc-MST-HN), and a trimeric Fc that blocks FcRn and/or immune complex-mediated cell activation through FcγR without triggering an immune reaction in several in vitro tests and validated in three mouse models of autoimmune disease.

Transgenic goats producing an improved version of cetuximab in milk

Therapeutic monoclonal antibodies (mAbs) represent one of the most important classes of pharmaceutical proteins to treat human diseases. Most are produced in cultured mammalian cells which is expensive, limiting their availability. Goats, striking a good balance between a relatively short generation time and copious milk yield, present an alternative platform for the cost-effective, flexible, large-scale production of therapeutic mAbs. Here, we focused on cetuximab, a mAb against epidermal growth factor receptor, that is commercially produced under the brand name Erbitux and approved for anti-cancer treatments. We generated several transgenic goat lines that produce cetuximab in their milk. Two lines were selected for detailed characterization. Both showed stable genotypes and cetuximab production levels of up to 10 g/L. The mAb could be readily purified and showed improved characteristics compared to Erbitux. The goat-produced cetuximab (gCetuximab) lacked a highly immunogenic epitope that is part of Erbitux. Moreover, it showed enhanced binding to CD16 and increased antibody-dependent cell-dependent cytotoxicity compared to Erbitux. This indicates that these goats produce an improved cetuximab version with the potential for enhanced effectiveness and better safety profile compared to treatments with Erbitux. In addition, our study validates transgenic goats as an excellent platform for large-scale production of therapeutic mAbs.

Fc Sialylation Prolongs Serum Half-Life of Therapeutic Antibodies

The long serum t _1/2 of IgGs is ensured by their interaction with the neonatal Fc receptor (FcRn), which salvages IgG from intracellular degradation. Fc glycosylation is thought not to influence FcRn binding and IgG longevity in vivo. In this article, we demonstrate that hypersialylation of asparagine 297 (N297) enhances IgG serum persistence. This polarized glycosylation is achieved using a novel Fc mutation, a glutamate residue deletion at position 294 (Del) that endows IgGs with an up to 9-fold increase in serum lifespan. The strongest impact was observed when the Del was combined with Fc mutations improving FcRn binding (Del-FcRn⁺). Enzymatic desialylation of a Del-FcRn⁺ mutant or its production in a cell line unable to hypersialylate reduced the in vivo serum t _1/2 of the desialylated mutants to that of native FcRn⁺ mutants. Consequently, our study proves that sialylation of the N297 sugar moiety has a direct impact on human IgG serum persistence.

Reduced hemidiaphragmatic paresis with extrafascial compared with conventional intrafascial tip placement for continuous interscalene brachial plexus block: a randomized, controlled, double-blind trial

Background.

The incidence of hemidiaphragmatic paresis with continuous interscalene brachial plexus block (CISB) can approach 100%. We tested the hypothesis that extrafascial placement of the catheter tip reduces the rate of hemidiaphragmatic paresis compared with intrafascial tip placement for CISB while providing effective analgesia.

Methods.

Seventy patients undergoing elective major shoulder surgery under general anaesthesia were randomized to receive an ultrasound-guided CISB plexus block for analgesia with the catheter tip placed either within (intrafascial group) or immediately outside (extrafascial group) the brachial plexus sheath midway between the levels of C5 and C6. Catheters were bolus dosed with ropivacaine 0.5% 20 ml before surgery, followed by an infusion of ropivacaine 0.2% at 4 ml h -1 for the first 2 days after surgery. The primary outcome was hemidiaphragmatic paresis measured by M-mode ultrasonography on postoperative day (POD) 1. Secondary outcomes included forced vital capacity, forced expiratory volume in 1 s, and rest pain scores.

Results.

The incidence of hemidiaphragmatic paresis on POD 1 was significantly reduced in the extrafascial group {intrafascial, 41% [95% confidence interval (CI) 25-59%]; extrafascial, 15% (95% CI 5-32%); P =0.01}. We were unable to detect a difference between groups in any of the functional respiratory outcomes or in rest pain scores [numerical rating scale (1-10): intrafascial, 3 (95% CI 2-3); extrafascial, 3 (95% CI: 2-4); P =0.93] on POD 1.

Conclusions.

Placement of the catheter tip immediately outside of the brachial plexus sheath reduced the incidence of hemidiaphragmatic paresis on POD 1 associated with ultrasound-guided CISB while providing effective analgesia after major shoulder surgery. Our results do not support the routine placement of the catheter tip within the brachial plexus sheath for CISB.

Clinical trial registration.

NCT02433561.

Colectomy Rates in Ulcerative Colitis are Low and Decreasing: 10-year Follow-up Data From the Swiss IBD Cohort Study

OBJECTIVES

Previous population-based studies in patients with ulcerative colitis [UC] revealed variable colectomy rates and colectomy-associated risk factors. Over the past two decades, a decrease in colectomy rates was observed. We assessed risk factors and colectomy rates over time in UC in the Swiss Inflammatory Bowel Disease Cohort Study [SIBDCS].

METHODS

Prospectively collected SIBDCS data, including disease history, baseline characteristics at enrolment, and course of disease, were retrospectively analysed. Cumulative and adjusted annual colectomy rates were calculated.

RESULTS

Among 1245 UC patients analysed [54.6% male], 114 [9.2%] underwent colectomy. We observed 5-, 10-, 15-, and 20-year cumulative colectomy rates after diagnosis of 4.1%, 6.4%, 10.4%, and 14.4% of patients, respectively. Male sex (odds ratio [OR] 1.54; p = 0.035), pancolitis at diagnosis [OR = 2.16; p = 0.005], younger age at diagnosis [OR 0.89 per 5 years of age; p = 0.006] and presence of extraintestinal manifestations [EIM] [OR 2.30; p < 0.001] were risk factors for undergoing colectomy. We did not observe a significant protective effect of smoking on colectomy risk [OR 0.64; p = 0.106]. The majority of colectomies were performed within first 10 years of disease onset, with a rapidly decreasing colectomy rate after 15 years. In patients diagnosed after 2003, colectomy was performed much earlier during and individual's disease course. Nevertheless, we found a significantly decreasing trend in yearly colectomy rates over time after 2005.

CONCLUSIONS

Crude and adjusted colectomy rates in Swiss UC patients were lower than those reported previously in the literature, and decreased over time.

Improved in vitro and in vivo activity against CD303-expressing targets of the chimeric 122A2 antibody selected for specific glycosylation pattern

Plasmacytoid dendritic cells (pDCs) play a central role for both innate and adaptive antiviral responses, as they direct immune responses through their unique ability to produce substantial concentrations of type I interferon (IFNs) upon viral encounter while also activating multiple immune cells, including macrophages, DCs, B, natural killer and T cells. Recent evidence clearly indicates that pDCs also play a crucial role in some cancers and several auto-immune diseases. Although treatments are currently available to patients with such pathologies, many are not fully efficient. We are proposing here, as a new targeted-based therapy, a novel chimeric monoclonal antibody (mAb) that mediates a strong cellular cytotoxicity directed against a specific human pDC marker, CD303. This antibody, ch122A2 mAb, is characterized by low fucose content in its human IgG1 constant (Fc) region, which induces strong in vitro and in vivo activity against human pDCs. We demonstrated that this effect relates in part to its specific Fc region glycosylation pattern, which increased affinity for CD16/FcγRIIIa. Importantly, ch122A2 mAb induces the down-modulation of CpG-induced IFN-α secretion by pDCs. Additionally, ch122A2 mAb shows in vitro high pDC depletion mediated by antibody-dependent cell-mediated cytotoxicity and antibody-dependent cellular phagocytosis. Remarkably, in vivo ch122A2 mAb efficacy is also demonstrated in humanized mice, resulting in significant pDC depletion in bloodstream and secondary lymphoid organs such as spleen. Together, our data indicates that ch122A2 mAb could represent a promising cytotoxic mAb candidate for pathologies in which decreasing type I IFNs or pDCs depleting may improve patient prognosis.

Medical education for equity in health: a participatory action research involving persons living in poverty and healthcare professionals

BACKGROUND

Improving the knowledge and competencies of healthcare professionals is crucial to better address the specific needs of persons living in poverty and avoid stigmatization. This study aimed to explore the needs and expectations of persons living in poverty and healthcare professionals in terms of medical training regarding poverty and its effects on health and healthcare.

METHODS

We conducted a participatory action research study using photovoice, a method using photography, together with merging of knowledge and practice, an approach promoting dialogue between different sources of knowledge. Nineteen healthcare professionals and persons from an international community organization against poverty participated in the study. The first phase included 60 meetings and group sessions to identify the perceived barriers between persons living in poverty and healthcare teams. In the second phase, sub-committees deployed action plans in academic teaching units to overcome barriers identified in the first phase. Data were analysed through thematic analysis, using NVivo, in collaboration with five non-academic co-researchers.

RESULTS

Four themes in regard to medical training were highlighted: improving medical students' and residents' knowledge on poverty and the living conditions of persons living in poverty; improving their understanding of the reality of those people; improving their relational skills pertaining to communication and interaction with persons living in poverty; improving their awareness and capacity for self-reflection. At the end of the second phase, actions were undertaken such as improving knowledge of the living conditions of persons living in poverty by posting social assistance rates, and tailoring interventions to patients' reality by including sociodemographic information in electronic medical records. Our findings also led to a participatory research project aiming to improve the skills and competency of residents and health professionals in regard to the quality of healthcare provided to persons living in poverty.

CONCLUSIONS

Medical training and residency programs should aim to improve students' and residents' relational skills, more specifically their communication skills, as well as their awareness and capacity for self-reflection, by helping them to identify and recognize their biases, and limitations.

Impact of the early use of immunomodulators or TNF antagonists on bowel damage and surgery in Crohn's disease

BACKGROUND

The impact of early treatment with immunomodulators (IM) and/or TNF antagonists on bowel damage in Crohn's disease (CD) patients is unknown.

AIM

To assess whether 'early treatment' with IM and/or TNF antagonists, defined as treatment within a 2-year period from the date of CD diagnosis, was associated with development of lesser number of disease complications when compared to 'late treatment', which was defined as treatment initiation after >2 years from the time of CD diagnosis.

METHODS

Data from the Swiss IBD Cohort Study were analysed. The following outcomes were assessed using Cox proportional hazard modelling: bowel strictures, perianal fistulas, internal fistulas, intestinal surgery, perianal surgery and any of the aforementioned complications.

RESULTS

The 'early treatment' group of 292 CD patients was compared to the 'late treatment' group of 248 CD patients. We found that 'early treatment' with IM or TNF antagonists alone was associated with reduced risk of bowel strictures [hazard ratio (HR) 0.496, P = 0.004 for IM; HR 0.276, P = 0.018 for TNF antagonists]. Furthermore, 'early treatment' with IM was associated with reduced risk of undergoing intestinal surgery (HR 0.322, P = 0.005), and perianal surgery (HR 0.361, P = 0.042), as well as developing any complication (HR 0.567, P = 0.006).

CONCLUSIONS

Treatment with immunomodulators or TNF antagonists within the first 2 years of CD diagnosis was associated with reduced risk of developing bowel strictures, when compared to initiating these drugs >2 years after diagnosis. Furthermore, early immunomodulators treatment was associated with reduced risk of intestinal surgery, perianal surgery and any complication.

Systematic analysis of factors associated with progression and regression of ulcerative colitis in 918 patients

BACKGROUND

Studies that systematically assess change in ulcerative colitis (UC) extent over time in adult patients are scarce.

AIM

To assess changes in disease extent over time and to evaluate clinical parameters associated with this change.

METHODS

Data from the Swiss IBD cohort study were analysed. We used logistic regression modelling to identify factors associated with a change in disease extent.

RESULTS

A total of 918 UC patients (45.3% females) were included. At diagnosis, UC patients presented with the following disease extent: proctitis [199 patients (21.7%)], left-sided colitis [338 patients (36.8%)] and extensive colitis/pancolitis [381 (41.5%)]. During a median disease duration of 9 [4-16] years, progression and regression was documented in 145 patients (15.8%) and 149 patients (16.2%) respectively. In addition, 624 patients (68.0%) had a stable disease extent. The following factors were identified to be associated with disease progression: treatment with systemic glucocorticoids [odds ratio (OR) 1.704, P = 0.025] and calcineurin inhibitors (OR: 2.716, P = 0.005). No specific factors were found to be associated with disease regression.

CONCLUSIONS

Over a median disease duration of 9 [4-16] years, about two-thirds of UC patients maintained the initial disease extent; the remaining one-third had experienced either progression or regression of the disease extent.

Epidemiology of unintentional drowning in a metropolis of the French Mediterranean coast: a retrospective analysis (2000-2011)

Drowning affects more than 500,000 people worldwide and is responsible for at least 350,000 deaths each year. In France, 1235 drowning resulting in 496 deaths were recorded in the summer 2012. This retrospective study has investigated the epidemiology of drowning in the city of Marseille (South of France) between 2000 and 2011. We identified 449 cases of unintentional drowning. The highest incidence was found among males with a median age of 36 years. The incidence was 5.3 victims per 10,000 inhabitants with a mortality rate of 1.2 per 10,000. These accidents occurred mainly at sea (89%) and during the summer season. A majority of drowning victims (69%) were admitted in a hospital. This is the only study in France to analyse data on drowning throughout the year and over a long period. Drowning is a serious condition burdened by 22% of victims who die.

Fractional treatment of aging skin with Tixel, a clinical and histological evaluation

OBJECTIVE

This study presents clinical results of Tixel, a new fractional skin resurfacing system based on thermo-mechanical ablation technology. Tixel employs a hot (400°C) metallic tip consisting of 81 pyramids. Treatment is performed by rapidly advancing the tip to the skin for a preset tip-skin contact duration. Thermal energy transfer to the skin creates micro-craters by evaporation.

METHODS

Treatment results with tip types, D and S, with high and low thermal conductivity, were evaluated. Twenty-six subjects received three facial treatments, with 4-5-week intervals between treatments, without analgesia or cooling. In addition, histopathologies of Tixel and CO2 laser were performed.

RESULTS

Crater properties are related to contact duration and to thermal conductivity. The D tip created char-free ablative craters 100-320 μm wide with a thermal zone 100-170 μm deep. The S tip created non-ablative coagulation preserving the epidermis. Skin complexion improvement was achieved in all subjects; average treatment pain of 3.1/10, downtime of 0-1 days, and erythema clearance of 3.5 days. Subject's satisfaction was 75% and wrinkle attenuation was achieved in 75% of the cases. There was no incidence of bleeding, scarring, or post-inflammatory hyperpigmentation.

CONCLUSIONS

Tixel may be used safely for ablative and non-ablative resurfacing with low pain, low downtime, and quick healing.

Selection of IgG Variants with Increased FcRn Binding Using Random and Directed Mutagenesis: Impact on Effector Functions

Despite the reasonably long half-life of immunoglogulin G (IgGs), market pressure for higher patient convenience while conserving efficacy continues to drive IgG half-life improvement. IgG half-life is dependent on the neonatal Fc receptor (FcRn), which among other functions, protects IgG from catabolism. FcRn binds the Fc domain of IgG at an acidic pH ensuring that endocytosed IgG will not be degraded in lysosomal compartments and will then be released into the bloodstream. Consistent with this mechanism of action, several Fc-engineered IgG with increased FcRn affinity and conserved pH dependency were designed and resulted in longer half-life in vivo in human FcRn-transgenic mice (hFcRn), cynomolgus monkeys, and recently in healthy humans. These IgG variants were usually obtained by in silico approaches or directed mutagenesis in the FcRn-binding site. Using random mutagenesis, combined with a pH-dependent phage display selection process, we isolated IgG variants with improved FcRn-binding, which exhibited longer in vivo half-life in hFcRn mice. Interestingly, many mutations enhancing Fc/FcRn interaction were located at a distance from the FcRn-binding site validating our random molecular approach. Directed mutagenesis was then applied to generate new variants to further characterize our IgG variants and the effect of the mutations selected. Since these mutations are distributed over the whole Fc sequence, binding to other Fc effectors, such as complement C1q and FcγRs, was dramatically modified, even by mutations distant from these effectors’ binding sites. Hence, we obtained numerous IgG variants with increased FcRn-binding and different binding patterns to other Fc effectors, including variants without any effector function, providing distinct “fit-for-purpose” Fc molecules. We therefore provide evidence that half-life and effector functions should be optimized simultaneously as mutations can have unexpected effects on all Fc receptors that are critical for IgG therapeutic efficacy.

Perceived barriers to healthcare for persons living in poverty in Quebec, Canada: the EQUIhealThY project

Introduction

Ensuring access to timely and appropriate primary healthcare for deprived patients is an issue facing all countries, even those with universal healthcare systems. There is a paucity of information on how patients living in a context of material and social deprivation perceive barriers in the healthcare system. This study combines the perspectives of persons living in poverty and of healthcare providers to explore barriers to responsive care for underserved persons with a view to developing equity-focused primary care.

Methods

In this participatory action research we used photovoice, together with a method known as ‘merging of knowledge and practice’ developed by ATD Fourth World, an international community organization working to eradicate poverty. The study was conducted in two teaching primary care practices in the Canadian province of Quebec. Participants consisted of 15 health professionals and six members of ATD Fourth World; approximately 60 group meetings were held. Data were analyzed through thematic analysis, in part with the involvement of persons living in poverty.

Results

Three main barriers to responsive care in a context of poverty were highlighted by all participants: the difficult living conditions of people living in poverty, the poor quality of interactions between providers and underserved patients, and the complexity of healthcare system organization and functioning.

Conclusion

Our research revealed that unhealthy living conditions prevent persons living in poverty from accessing quality healthcare and maintaining good health. Also, the complexity of the healthcare system’s organization and functioning has a negative impact on the interactions with healthcare providers. Changes in policy and practice are needed to address those barriers and to achieve greater equity and provide more responsive care for persons living in poverty.

119 A SHORT PERICONCEPTIONAL MATERNAL HYPERGLYCEMIA IS SUFFICIENT TO DISRUPT THE FETO-PLACENTAL PHENOTYPE IN A RABBIT MODEL

Pre-gestational type 1-diabetes (T1D) increases the risk of miscarriage and congenital malformations and programs the offspring to develop metabolic syndrome in adulthood. Management of maternal diabetes is essential during gestation but could be also highly important around the time of conception. Using a rabbit model, the effects of maternal T1D during the periconceptional period on pre-implantation blastocysts have been well documented, but the effects on feto-placental phenotype at 28 dpc (term = 31 days) has not been explored. Diabetes was induced by Alloxan in dams 7 days before mating. Glycemia was maintained at 15 to 20 mmol L–1 with exogenous insulin injections. At 4 dpc, embryos were collected and transferred into nondiabetic recipients. At 28 dpc, control (C) and diabetic (D) fetuses were collected for biometric records, placental analyses including stereology and gene expression, and lipid profiles of feto-placental tissues by gas chromatography. Lipid data were analysed by principal component analysis. D-fetuses were growth retarded, hyperglycemic, and dyslipidemic compared with C fetuses. Moreover, placental efficiency was much higher in D- than in C-fetuses. The volume density of fetal vessels was significantly decreased in D-placentas compared to C-placentas, whereas the volume density of trophoblast tended to increase (P = 0.051). This morphometric disruption was associated with a deregulation of the expression of genes related to nutrient supply and lipid metabolism. In fetal plasma, a specific fatty acid signature was observed in D- and C-groups. Moreover, the composition of placental and fetal liver membranes differed according to maternal status and fetal sex. Tissues from D-fetuses contained significantly more n-6 polyunsaturated fatty acids compared with C. Docosahexaenoic acid decreased whereas linoleic acid increased in the cardiac membranes of D-fetuses, indicating a higher risk of ischemia. This study demonstrates that exposure to high plasma glucose during the short periconceptional period is sufficient to adversely program fetal phenotype by reducing fetal growth, altering placental function and lipid profiles in all fetal tissues.

The gap between scientific evidence and clinical practice: 5-aminosalicylates are frequently used for the treatment of Crohn's disease

BACKGROUND

There is uncertain evidence of effectiveness of 5-aminosalicylates (5-ASA) to induce and maintain response and remission of active Crohn's disease (CD), and weak evidence to support their use in post-operative CD.

AIM

To assess the frequency and determinants of 5-ASA use in CD patients and to evaluate the physicians' perception of clinical response and side effects to 5-ASA.

METHODS

Data from the Swiss Inflammatory Bowel Disease Cohort, which collects data since 2006 on a large sample of IBD patients, were analysed. Information from questionnaires regarding utilisation of treatments and perception of response to 5-ASA were evaluated. Logistic regression modelling was performed to identify factors associated with 5-ASA use.

RESULTS

Of 1420 CD patients, 835 (59%) were ever treated with 5-ASA from diagnosis to latest follow-up. Disease duration >10 years and colonic location were both significantly associated with 5-ASA use. 5-ASA treatment was judged to be successful in 46% (378/825) of treatment episodes (physician global assessment). Side effects prompting stop of therapy were found in 12% (98/825) episodes in which 5-ASA had been stopped.

CONCLUSIONS

5-Aminosalicylates were frequently prescribed in patients with Crohn's disease in the Swiss IBD cohort. This observation stands in contrast to the scientific evidence demonstrating a very limited role of 5-ASA compounds in the treatment of Crohn's disease.

Combined glyco- and protein-Fc engineering simultaneously enhance cytotoxicity and half-life of a therapeutic antibody

While glyco-engineered monoclonal antibodies (mAbs) with improved antibody-dependent cell-mediated cytotoxicity (ADCC) are reaching the market, extensive efforts have also been made to improve their pharmacokinetic properties to generate biologically superior molecules. Most therapeutic mAbs are human or humanized IgG molecules whose half-life is dependent on the neonatal Fc receptor FcRn. FcRn reduces IgG catabolism by binding to the Fc domain of endocytosed IgG in acidic lysosomal compartments, allowing them to be recycled into the blood. Fc-engineered mAbs with increased FcRn affinity resulted in longer in vivo half-life in animal models, but also in healthy humans. These Fc-engineered mAbs were obtained by alanine scanning, directed mutagenesis or in silico approach of the FcRn binding site. In our approach, we applied a random mutagenesis technology (MutaGen™) to generate mutations evenly distributed over the whole Fc sequence of human IgG1. IgG variants with improved FcRn-binding were then isolated from these Fc-libraries using a pH-dependent phage display selection process. Two successive rounds of mutagenesis and selection were performed to identify several mutations that dramatically improve FcRn binding. Notably, many of these mutations were unpredictable by rational design as they were located distantly from the FcRn binding site, validating our random molecular approach. When produced on the EMABling(®) platform allowing effector function increase, our IgG variants retained both higher ADCC and higher FcRn binding. Moreover, these IgG variants exhibited longer half-life in human FcRn transgenic mice. These results clearly demonstrate that glyco-engineering to improve cytotoxicity and protein-engineering to increase half-life can be combined to further optimize therapeutic mAbs.

Topical therapy is underused in patients with ulcerative colitis

The availability of new topical preparations for the treatment of left sided ulcerative colitis offers a therapy optimization for many patients. Rectal application of steroids and 5-aminosalicylic acid (5-ASA) is associated with fewer side effects and has a higher therapeutic efficacy in left-sided colitis as compared to a systemic therapy. Therefore, we were interested in the use of topical therapy in patients with ulcerative colitis. The key question was whether topical treatment is more frequently used than oral therapy in patients with proctitis and left sided colitis. Data of 800 patients of the Swiss IBD cohort study were analyzed. Sixteen percent of patients of the cohort had proctitis, 21% proctosigmoiditis and 41% pancolitis. Topical therapy with 5-ASA or corticosteroids was given in 26% of patients with proctitis, a combined systemic and topical treatment was given in 13%, whereas systemic treatment with 5-ASA without topical treatment was given in 29%. Proportion of topical drug use decreased with respect to disease extension from 39% for proctitis to 13.1% for pancolitis (P=0.001). Patients with severe colitis received a significantly higher dose of topical 5-ASA than patients in remission. Side effects of topical or systemic 5-ASA or budesonide treatment were less frequently seen compared to other medications. Topical treatment was frequently stopped over time. The quality of life was the same in patients with limited disease compared to patients with pancolitis. Topical treatment in proctitis patients was underused in Switzerland. Since topical treatment is safe and effective it should be used to a larger extend.

Measurement of the binding energies of the organic-metal perylene-teracarboxylic-dianhydride/Au111 bonds by molecular manipulation using an atomic force microscope

Based on single molecule manipulation experiments in a combined scanning tunneling microscope/frequency modulated atomic force microscope, we quantify the individual binding energy contributions to an organic-metal bond experimentally. The method allows the determination of contributions from, e.g., local chemical bonds, metal-molecule hybridization, and van der Waals interactions, as well as the total adsorption energy.

A novel treatment for ovarian cancer (OC): Anti-Müllerian inhibiting substance type II receptor (MISRII) humanized monoclonal antibody (mAb) 3C23K—Preclinical validation

5069

Background: Expressed on most OC subtypes while displaying a restricted expression profile in adult normal tissues, MISRII represents a potentialtarget for OC immunotherapy. We present here the preclinical assessment of a humanized anti-MISRII EMABling mAb, 3C23K. Methods: Either quantitative RT-PCR or immunohistochemistry (IHC) studies were performed to confirm MISRII expression profile in Granulosa Cell Tumor (GCT) or Epithelial OC (EOC) patient samples and to evaluate tissue cross-reactivity. For in vitro and in vivo experiments, we have generated 4 patient-derived MISRII expressing EOC cell lines. Xenograft studies were conducted in swiss nude mice on established tumors (100 mm3). Mice received 2 to 3 weekly i.p. injections (10 mg/kg/inj) for 4 to 6 wks and tumor volumes were compared with control groups. Comparison of i.p. vs i.v. injections were assessed as well as combination with carboplatin (once a week for 4 weeks, 60 mg/kg/inj). In addition, 3C23K plasma level was monitored to determine half-life. Results: 1) Target validation: we confirmed by IHC the expression of MISRII in most OC tissue sections (4/4 GCT and 13/14 EOC), meanwhile, MISRII mRNA was only detected in 7/48 normal tissues. 2) In vitro assessment: tested in vitro 3C23K displayed both cytotoxic (ADCC) and anti-proliferative activities. 3) In vivo assessment: in the mouse xenograft models 3C23K exhibited a strong anti-tumoral activity as measured by tumor volume, with T/C ratios reaching values below 0.42 shortly after the initiation of treatment. No differences in efficacy were noticed between i.p. and i.v. injections or between thrice vs twice a week administrations. In addition, similar half lives were observed for 3C23K injected either i.v. (96.9 h) or i.p (113.5 h). Finally, the combination of 3C23K with carboplatin (CP), a standard of care in OC, exhibited an even stronger anti-tumor activity with T/C values at D22 of 0.06 (3C23K+CP), 0.18 (3C23K) and 0.69 (CP) vs vehicle. Conclusions: 3C23K represents a promising candidate for OC targeted therapy and a dose-escalation phase I study is planned in patients with OC.

Abstract 2528: 3C23K: an anti-human Müllerian inhibiting substance type II receptor humanized monoclonal antibody for ovarian cancer targeted therapy

Asymptomatic in early stages, ovarian cancer is a “silent killer” representing the fifth leading cause of female deaths in western countries. Every year 56,967 women in Europe and USA die as a consequence of this disease. The incidence of ovarian cancer is forecast to undergo a 13 % increase in the next eight years in the seven major developed countries to reach about 72,000 annual cases in 2019. Due to the limitations of the current therapeutic approaches, there is a strong need for novel, more efficient, therapies. For this reason, we have produced a humanized monoclonal antibody 3C23K targeting the human Müllerian Inhibiting Substance type II Receptor (MISRII), expressed on most ovarian cancer subtypes, including epithelial ovarian cancer (EOC) representing more than 90% of ovarian cancers. This monoclonal antibody derives from the murine monoclonal antibody 12G4 and displays a particular glycosylation profile known to favor effector recruitment (EMABling®) as previously demonstrated in vitro. In vivo, we also showed that 3C23K exhibited a significant effect on tumor growth against several ovarian tumor xenografted models derived from patient primary EOC tumors. In this study, we first confirmed by peptide microarray that the epitope of 3C23K antibody was strictly identical to that of 12G4 antibody and a 3D-model of the full MISRII molecule was generated in order to better localize the 3C23K epitope. Furthermore, SPR studies demonstrated cross-reactivity of 3C23K with MISRII of rabbit, dog, pig, cow and primate. In vivo, antitumor activity of 3C23K against xenografted EOC tumor models was confirmed with various concentrations and treatment schedules. Moreover, interestingly, we constructed a mutant form of 3C23K harboring two mutations in the Fc region (G236R/L328R) in order to prevent binding to both murine and human FcαRs, and demonstrated that such a modification abolished antitumor activity. This data confirmed in vivo that recruitment of effectors is essential for 3C23K efficacy. Finally, in order to anticipate clinical treatment of ovarian cancers, 3C23K was tested in vivo in combination with carboplatin. Combination, when compared with treatment of each product alone, resulted in more than additive antitumor activity. Altogether these data showed that humanized monoclonal antibody 3C23K represents a promising candidate for ovarian cancer immunotherapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2528. doi:1538-7445.AM2012-2528

Reduction in thigh circumference and improvement in the appearance of cellulite with dual-wavelength, low-level laser energy and massage

OBJECTIVES

This study evaluated the efficacy and safety of a low-level, dual-wavelength laser energy and massage device for improving the appearance of cellulite and reducing thigh circumference.

METHODS

Subjects (n = 83) with mild to moderate cellulite enrolled in this IRB-approved, open-label, multicenter study. Their right or left thighs received eight treatments with a low-level, dual-wavelength laser and massage device. The untreated contralateral thigh served as a control. Circumferences of the upper, middle, and lower thighs (treated and untreated) were measured before the fifth and eighth treatments and 1 month after the final treatment.

RESULTS

Reduction in thigh circumference of the treated areas exceeded those of the control areas for the upper, middle, and lower thigh in most subjects. The maximum reduction (-0.82 cm) occurred in the upper thigh at 1 month. The mean reduction of the upper, middle, and lower thigh circumferences was -0.64 cm for the treated thighs compared to -0.20 cm for untreated thighs. The difference was significant (p < 0.0001). Fifty-nine (71.1%) treatment thighs lost circumference compared to 44 (53.0%) control thighs. Resolution of adverse effects including erythema, swelling, and increased urination was seen within 30 minutes after treatment. All were resolved without sequelae and within the expected duration.

CONCLUSION

The low-level, dual-wavelength laser energy and massage device safely improves the appearance of cellulite while reducing thigh circumference.

Abstract 4574: Towards a new targeted therapy for ovarian cancer : Development of an anti-human müllerian inhibiting substance type II receptor humanized antibody

Asymptomatic in early stages, ovarian cancer is a “silent killer” corresponding to the 5th cause of female deaths in US. In 2010 it is estimated that 21,880 women in US will be diagnosed with ovarian cancer. Due to the limitations of the current therapeutic approaches, there is a strong need for novel, more efficient, therapies. We describe here a humanized monoclonal antibody 3C23K targeting the human Müllerian Inhibiting Substance type II Receptor (MISRII), expressed on most ovarian cancer subtypes, including epithelial ovarian cancer (EOC) representing more than 90% of ovarian cancers.

Starting from murine monoclonal antibody 12G4, 3C23K was obtained following chimerization, humanization by CDR grafting and affinity maturation. Moreover, 3C23K displays a particular glycosylation profile known to favor effector recruitment in vitro and in vivo (EMABling®). Assessed on MISRII transfected cells (cov434-MISRII), 3C23K was characterized by an affinity constant to the antigen increased by 3 fold as compared to murine 12G4. In order to evaluate 3C23K efficacy in vitro and in vivo, we have established several MISRII expressing cell lines derived from patient primary EOC tumors. Functional characterization of 3C23K has been carried out in vitro, including antibody-dependent cell-mediated cytotoxicity (ADCC), complement dependent cytotoxicity, apoptosis and intracellular signaling. In particular, 3C23K was found to display a higher ADCC activity on MISRII expressing cell lines as compared to the same sequence expressed in CHO cells. In vivo, 3C23K exhibited a significant effect on tumor growth against several ovarian tumor xenografted models derived from patient primary EOC tumors.

Altogether these data strongly suggest that humanized monoclonal antibody 3C23K may represent a promising candidate for ovarian cancer immunotherapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4574. doi:10.1158/1538-7445.AM2011-4574

Rise and fall of an anti-MUC1 specific antibody

BACKGROUND

So far, human antibodies with good affinity and specificity for MUC1, a transmembrane protein overexpressed on breast cancers and ovarian carcinomas, and thus a promising target for therapy, were very difficult to generate.

RESULTS

A human scFv antibody was isolated from an immune library derived from breast cancer patients immunised with MUC1. The anti-MUC1 scFv reacted with tumour cells in more than 80% of 228 tissue sections of mamma carcinoma samples, while showing very low reactivity with a large panel of non-tumour tissues. By mutagenesis and phage display, affinity of scFvs was increased up to 500fold to 5,7×10(-10) M. Half-life in serum was improved from below 1 day to more than 4 weeks and was correlated with the dimerisation tendency of the individual scFvs. The scFv bound to T47D and MCF-7 mammalian cancer cell lines were recloned into the scFv-Fc and IgG format resulting in decrease of affinity of one binder. The IgG variants with the highest affinity were tested in mouse xenograft models using MCF-7 and OVCAR tumour cells. However, the experiments showed no significant decrease in tumour growth or increase in the survival rates. To study the reasons for the failure of the xenograft experiments, ADCC was analysed in vitro using MCF-7 and OVCAR3 target cells, revealing a low ADCC, possibly due to internalisation, as detected for MCF-7 cells.

CONCLUSIONS

Antibody phage display starting with immune libraries and followed by affinity maturation is a powerful strategy to generate high affinity human antibodies to difficult targets, in this case shown by the creation of a highly specific antibody with subnanomolar affinity to a very small epitope consisting of four amino acids. Despite these "best in class" binding parameters, the therapeutic success of this antibody was prevented by the target biology.

Pneumatic skin flattening (PSF): A novel technology for marked pain reduction in hair removal with high energy density lasers and IPLs

BACKGROUND

Intense pulsed light (IPL) aesthetic treatment, such as hair removal from large areas, is often very painful. The problems of pain and discomfort can be divided into two different phases: immediate acute pain and the long-term, milder, post-treatment discomfort also associated with erythema. The immediate acute pain is felt during each treatment pulse and can accumulate to an intolerable sensation after a few shots, resulting in the necessity of either using topical analgesic creams which have several limitations or else to considerably slow down the process and/or apply less efficient low-energy densities. The immediate pain is created by the stimulation of sensory nerves located near the basal layer of the epidermis and adjacent to the treated hair follicles. There is an interest in a technology which would significantly reduce acute pain and post-treatment erythema, without the necessity of lowering the energy density or speed of treatments.

OBJECTIVES

To examine the advantages of pneumatic skin flattening (PSF) with negative pressure: (i) for the reduction or elimination of pain, without chilling the skin, during hair removal with high energy density IPLs and pulsed lasers; (ii) for the reduction of post-treatment erythema; and (iii) for the enhancement of hair removal.

MATERIALS AND METHODS

We have removed hair from large areas such as legs and backs with a high-energy (42 J/cm2) pulsed diode laser and an IPL (15-20 J/cm2). Room temperature gel was applied to the skin before treatment. In all cases but one, skin was not chilled by external cooling devices. We utilized a vacuum chamber and a transparent sapphire window to generate deep negative pressure in the treatment site and flatten the skin against the window. The level of applied vacuum was in the 200-600 mmHg range. We have compared the level of pain (I-V according to a modified McGill Pain Questionnaire) and the efficacy of hair removal on a total of 40 treatment sites The results of the vacuum-assisted treatment sites were compared with the results on adjacent control areas, obtained without the application of vacuum. Post-treatment erythema was also compared.

RESULTS AND CONCLUSIONS

PSF significantly reduces pain in all patients, even when higher (+30%) treatment energy levels are applied. Skin is well protected thermally by the conductive sapphire window. Post erythema and edema is considerably reduced, as well. Hair removal efficacy is preserved or enhanced. Treatment is faster and is uninterrupted by pain, without the necessity to apply topical anesthetic over a large area. Blood expulsion resulting from flattening the skin has also enabled the treatment of thin hair in light-skinned patients, using yellow and green wavelengths (540 nm cut-off filter) and short pulse durations with a higher efficacy than with the 650 nm cut-off filter.

A 35-month profilometric and clinical evaluation of non-ablative remodeling using a 1540-nm Er:glass laser

BACKGROUND/OBJECTIVE

As remodeling is getting more popular with patients, long-term studies are becoming necessary. The aim of this 35-month clinical study was to evaluate the long-term benefits obtained using a 1540-nm Er:glass laser for non-ablative remodeling of perioral and periorbital rhytids. The role of maintenance treatments was also investigated.

STUDY DESIGN/METHODS

Eleven women with periorbital and perioral rhytids underwent a series of five treatments at 6-week intervals with an Er:glass laser. Five patients subsequently received two maintenance retreatments and six did not. The maintenance treatments were performed at 14 and 20 months. Silicone imprints were performed to measure anisotropy before treatment, at 6 months, at 14 months and at 35 months. Patient self-evaluation/questionnaire was also done to assess adverse effects and subjective clinical improvement.

RESULTS

For all 11 patients, the percentage of anisotropy reduction was 41.21% at 6 months, 51.76% at 14 months and 29.87% at 35 months. No adverse effects were noted. Patient satisfaction was high at the end of the evaluation. Retreated patients were more satisfied than non-retreated ones. However, there was no difference in the anisotropy factor between the two groups.

CONCLUSION

Treatment of facial rhytids with a non-ablative 1540-nm Er:glass laser system can produce benefits that persist over 2 years after the last treatment.