Citoxlab Group – January 2019 Newsletter

Latest news from the Citoxlab Group

Assessment of immunomodulators in pharmacodynamics and safety studies presented at Eurotox in Brussels in September 2018

Immunomodulatory drugs are increasingly being developed for the treatment of inflammatory disorders, auto-immune diseases, cancer and organ transplant rejection. These compounds alter signaling pathways involved in the immune response and thus can exert undesiderable immunotoxic effects, mainly by exaggerated pharmacodynamics. More recently, immunomodulators tend to affect more specific, narrow pathways in the immune system, which sometimes makes it difficult to predict potential immunological safety risks in preclinical models.

During a recent Citoxlab-Sponsored symposium at Eurotox in Brussels, Dr Michael Kammueller from the Novartis Institute for Biomedical Research (Basel) Immunology Group for Translational Medicine−Preclinical Safety, presented two case studies. These case studies illustrated the risk evaluation of opportunistic infections associated with treatments using immunosuppressant compounds, while also taking human genetic data and data from in vitro and in vivo preclinical models into account.
A second presentation given by Dr Philippe Ancian, Head of Biomarkers at Citoxlab, showed recent developments in the T-cell dependent antibody response (TDAR) model in the non-human primate (NHP) used to evaluate immune stimulation and function. This model (developed in partnership with Bayer AG) to evaluate the use of sub-optimal doses of model antigens such as KLH and an anti-CTLA-4 antibody as a positive control. A standardized study design for evaluation of the immune stimulation pharmacodynamics in NHPs has been proposed with multiple readouts such as anti-KLH IgGs and IgMs, as well as IFN- γ and IL-4 ELISpot in in vitro stimulated splenocytes. Treatment with the positive control has been shown to increase both humoral and cellular immune responses in this model, illustrating the utility of this evaluation method. Inter-individual variation in the responses against this single antigen has been observed, and some animals were shown to be low-responders to KLH. In order to reduce the inter-individual variability, another model was proposed with multiple antigen immunizations. Multiple readouts, including anti-antigen antibodies, ELISpot and lymphocyte proliferation after in vitro stimulation of PBMC (peripheral blood mononuclear cells) were assessed to demonstrate the immune stimulation of an adjuvant in cellular and humoral immune responses against multiple antigens.

The incorporation of multiple immunomonitoring end-points in NHP studies allows comprehensive monitoring of various aspects of the immune response that are involved and can be used for compounds with various mechanisms of action. These methods are now currently used at Citoxlab for demonstration of the pharmacodynamic activity of immune stimulating compounds in regulatory toxicology studies.

Citoxlab accelerates investment in technologies to support development of cell therapies

Citoxlab has pioneered regulatory toxicology assessments for cell therapies with more than a decade of experience in the field. Recently, gene editing technologies have propelled cell therapies to the forefront of the biomedical research landscape across many innovative applications, including oncology, metabolic diseases, neurology, heart failure and rare diseases. These technological advances have significantly raised the interest in immuno-conditioning of immunocompromised non-clinical models for regulatory testing of human cell therapies. Based on our historical database, recognized as the largest available worldwide, Citoxlab has accelerated investment to characterize commonly used non-clinical models required for cell therapy safety testing. Biodistribution/ engraftment/ persistence, general toxicity, and tumorigenicity are fundamental to cell therapy development, and are supported not only by a broad range of immunology and immunohistochemistry assays, but also technologies such as Next Generation Sequencing (NGS) which has been validated at Citoxlab. We have multi-disciplinary teams  constantly working throughout the continuum, from design to reporting for these very unique toxicology studies. With our involvement in diverse programs, our teams of experts have established strategies addressing the requirements from regulatory agencies for non-clinical safety testing, enabling initiation of time-sensitive clinical trials. We are pleased to engage into active partnerships with our clients to ensure success of their next generation of therapies, often to the benefit of patients without any therapeutic alternatives.

 

Evaluation of brake dust toxicity containing asbestos by inhalation route

Citoxlab Hungary recently completed a 28-day inhalation study in rats to investigate the potential toxicity of inhaled brake dust (from brakes manufactured with chrysotile asbestos) to compare the results to the effects of chrysotile (white asbestos) and crocidolite (blue asbestos). The primary purpose of this project was to determine whether brake dust which contains chrysotile can cause pathological response once inhaled. A separate group of only chrysotile was included as a comparison. The pure crocidolite asbestos was included as a known potent agent causing mesothelioma.
Chrysotile and crocidolite are both silica fibers and both are referred to as asbestos, but they belong to two distinct mineralogical groups. Previous studies suggested that their toxicity might also be different and one of the aims of this study was to obtain further information about this.

In the fiber groups, the study differentiated between similar exposures to chrysotile and crocidolite asbestos. There was no fiber related macrophage response in the air control, brake dust or chrysotile groups, but fiber laden macrophage accumulation and interstitial fibrosis was observed following crocidolite exposure. Confocal microscopy images (determined following deep freezing of the chest wall at sacrifice) revealed no difference between the air control, brake dust and chrysotile exposure groups, and no difference in the visceral or parietal pleura thickness within these groups. The crocidolite exposure resulted in more than double the thickness of the visceral pleura and parietal pleura, with associated extensive inflammatory response and collagen development including adhesions between the visceral and parietal surfaces.

These results provided a basis for the design of an on-going 90-day study to further characterize any possible effect from chrysotile containing brake dust following longer term exposure.

Long-term catheterization in minipigs

It is well known that for repeated and long-term intravenous administration in minipigs, it is necessary to use catheters implanted in the large vessels. Minipigs lack the easily-accessible peripheral veins that are present in other species. There are many different catheterization techniques described in the literature. With each of them, it is important to maintain catheter patency over longer periods. At Citoxlab, we have developed various methods and techniques, including catheters implanted into the jugular vein and exteriorized near the shoulders, attached to a Vascular Access Port (VAP), as well as catheters introduced via the ear vein. Age and size of the animal can have a big influence on the chosen technique and its likelihood of success. In order to maintain patency for long durations, we understand that we have to apply specific procedures. In a recent study, we succeeded in maintaining catheter patency using VAPs in as many as 40 minipigs for several months.

In this study, catheters were implanted in the animals several weeks prior to treatment. The VAP consisted of a titanium, volcano-shaped reservoir and outlet catheter with a silicone septum (CP4AC Titanium ClearportTM; UNO Roestvaststaal BV). The reservoir was sutured in place subcutaneously, through holes at the base, and connected to a hydrocoated polyurethane catheter (7 french, 60 cm with 3 retention beads; UNO Roestvaststaal BV). The catheter was implanted in the vena jugularis.

Catheter patency was achieved by flushing at least every second day with sterile 0.9% saline and then with heparinized (100 U/mL) sterile 0.9% saline or TauroLockTM Hep500 to produce a heparin lock in the catheter for the first 2 weeks. During this procedure, it was important to work in aseptic conditions, carefully disinfecting the skin and using sterile equipment. From approximately 2 weeks after catheterization until commencement of treatment, the VAP was flushed 1 to 2 times per week. During the treatment period, the VAP was flushed once weekly. Using this technique, catheters maintained patency for a 5-month period, during which time the animals were dosed once monthly in the study.

This method of long-term catheterization can also be used for blood sampling. We concluded that long-term IV administrations and/or sampling in minipigs should be included as a standard technique at Citoxlab.

 

Latest review on preclinical models for safety and performance evaluation of orthopedic biomaterials, published in Elsevier’s Encyclopedia of Biomedical Engineering

AccelLAB, a member of Citoxlab Group, is pleased to announce that it is featured in Elsevier’s 1st Edition of the Encyclopedia of Biomedical Engineering. Edited by Prof. Roger Y. Narayan (Dept. of Biomedical Engineering; University of North Carolina). This large multidisciplinary collection represents a helpful guide for biomaterial scientists, biomedical engineers, governmental and industrial researchers, and medical practitioners to support their research activities. Leading scholars from around the world have contributed with the most recent concepts in the fields of biomaterials, bioengineering, medical devices, regenerative medicine, biomechanics, modeling, medical imaging, instrumentation and biocompatibility evaluation. This important reference work of over 200 chapters and 2054 pages was just recently published by Elsevier. In addition to biomedical engineering applications, this book covers advances in cardiology, drug delivery, gene therapy, orthopedics, ophthalmology, sensing and tissue engineering.

Having been very honored to have received this invitation to contribute, AccelLAB’s Dr. Nicolette Jackson and Dr. Michel Assad have reviewed the latest biocompatibility and preclinical animal models for orthopedic research in a unique book chapter entitled: “Biocompatibility evaluation of orthopedic biomaterials and medical devices: a review of safety and efficacy models”. Already available on-line, this chapter presents state-of-the-art animal models, and specifically appears in the encyclopedia’s Medical Device section, edited by renowned biomaterials expert, Prof. Diego Mantovani (Director, Lab for Biomaterials and Bioengineering; Laval University). This review summarizes the biocompatibility framework to demonstrate an appropriate biological response, as well as orthopedic implant innocuity, efficacy, functionality and performance. The most recent advances in preclinical models for study designs that simulate the clinical setting in the field of orthopedics are presented. Histology, histomorphometry, and histopathology analyses, as well as imaging modalities and mechanical testing, are also described in order to evaluate orthopedic biomaterials for their safety and performance.

Xenometrics renamed Citoxlab USA and appoints Dr Kyle Kappeler, B.S., Ph.D., as Director of Toxicology

We are pleased to announce that Xenometrics, Kansas, has changed its company name to Citoxlab USA. There has been no change in the range of services and the name change will not impact ongoing collaborations with our industry partners or any agreement terms. The name change is a logical consequence of the acquisition that was made by Citoxlab in 2017. This new name reflects the global presence as a fully fledged subsidiary of the Citoxlab Group, allowing the Kansas site to incorporate Citoxlab’s corporate name recognition into its business activities, which include service lines beyond those offered by Xenometrics.

Furthermore, we are happy to announce the appointment of Dr Kyle Kappeler, B.S., Ph.D. as the Director of Toxicology at our Kansas site.  Dr. Kappeler has over 6 years experience in the contract research environment with a primary focus on General Toxicology.  Dr. Kappeler gained his experience and knowledge in General Toxicology having served as a Senior Toxicologist/Study Director at WIL Research and MRIGlobal in support of IND, Global Registration, and Food Safety Assessment submissions in accordance with FDA, OECD, US EPA, ICH and/or EFSA guidelines.  In addition to serving as a Study Director, Dr. Kappeler was the Associate Section Manager for the Biological, Animal Health and Toxicology Group at MRIGlobal where he was responsible for managing senior scientific staff, writing proposals and providing scientific input on study design development.  Dr. Kappeler holds a B.S. from Mesa State College and a Ph.D. from the University of South Dakota. In his current role, Dr. Kappeler is responsible for the overall conduct and management of toxicology (including reproductive toxicology) studies, including supervising toxicologists and support group managers (Analytical Chemistry, Clinical Pathology, Necropsy and Histology).  He also has oversight of technical conduct, interpretation, analysis, documentation, and reporting of study results.

SOLVO Biotechnology opens new central Budapest location

In August, SOLVO Biotechnology, a member of the Citoxlab Group, successfully completed a move to a new site in central Budapest, relocating the Budaörs laboratory site that the company has operated since 2004. The new location on the banks of the River Danube within the Science Park complex is a 600 m2 state-of-the art facility comprising both offices and laboratory space, and provides increased capacity to support the continued strong growth in demand for SOLVO’s in vitro ADME-Tox services. The new site will enable further expansion of SOLVO’s bioanalytical capabilities, research and development activities, high-throughput screening, and metabolism services over the coming months, details of which will be announced on the SOLVO Biotechnology website. In addition to the Budapest site, SOLVO Biotechnology maintains another laboratory site in Szeged, Hungary, in addition to sales offices in Seattle, Boston, and San Francisco in the United States. SOLVO Biotechnology is the leading provider of drug transporter products and services to clients in over 40 countries worldwide.