Annemarie Lang

University of Pennsylvania | UP · McKay Orthopaedic Research Laboratory

To assess pain in mouse models of bone fractures, currently applied assessment batteries use combinations of clinical signs with spontaneous behaviours and model-specific behaviours, including walking and weight-bearing behaviour. Rearing behaviour – an upright position on the hindlimbs – has a motivational and an ambulatory component. Thus, rearin...

Adequate pain management is essential for ethical and scientific reasons in animal experiments and should completely cover the period of expected pain without the need for frequent re-application. However, current depot formulations of Buprenorphine are only available in the USA and have limited duration of action. Recently, a new microparticulate...

Bone generally displays a high intrinsic capacity to regenerate. Nonetheless, large osseous defects sometimes fail to heal. The treatment of such large segmental defects still represents a considerable clinical challenge. The regeneration of large bone defects often proves difficult, since it relies on the formation of large amounts of bone within...

Endochondral ossification requires coordinated mobilization of osteoblast precursors with blood vessels. During adult bone homeostasis, vessel adjacent osteoblast precursors respond to and are maintained by mechanical stimuli; however, the mechanisms by which these cells mobilize and respond to mechanical cues during embryonic development are unkno...

Skeletal development depends on coordinated angiogenesis and osteogenesis. Bone morphogenetic proteins direct bone development by activating SMAD1/5 signaling in osteoblasts. However, the role of SMAD1/5 in skeletal endothelium is unknown. Here, we found that endothelial cell-conditional SMAD1/5 depletion in juvenile mice caused metaphyseal and dia...

Osteoarthritis (OA) is the most common form of arthritis and a major source of pain and disability in the adult population. There is a significant unmet medical need for the development of effective pharmacological therapies for the treatment of OA. In addition to spontaneously occurring animal models of OA, many experimental animal models have bee...

The adoption of Directive 2010/63/EU on the protection of animals used for scientific purposes has given a major push to the formation of Three Rs initiatives in the form of centres and platforms. These centres and platforms are dedicated to the so-called Three Rs, which are the Replacement, Reduction and Refinement of animal use in experiments. AT...

With increasing age, the risk of bone fractures increases while regenerative capacity decreases. This variation in healing potential appears to be linked to adaptive immunity, but the underlying mechanism is still unknown. This study sheds light on immunoaging/inflammaging, which impacts regenerative processes in aging individuals. In an aged precl...

Adequate pain management is essential for ethical and scientific reasons in animal experiments and should completely cover the period of expected pain without the need for frequent re-application. However, current depot formulations of Buprenorphine are only available in the USA and have limited duration of action. Recently, a new microparticulate...

In this issue of Laboratory Animals, Fabienne Ferrara and her collaborators1 explore the fashionable concept of ‘Culture of Care’ with a novel and important angle. Rather than addressing the topic from a regulatory perspective, as encouraged by the European Commission, with an emphasis on the 3Rs and animal welfare, they take a different approach a...

Public awareness and discussion about animal experiments and replacement methods has greatly increased in recent years. The term 'the Three Rs', which stands for the Replacement, Reduction and Refinement of animal experiments, is inseparably linked in this context. A common goal within the Three Rs scientific community is to develop predictive non-...

The initial phase of fracture healing is crucial for the success of bone regeneration and is characterized by an inflammatory milieu and low oxygen tension (hypoxia). Negative interference with or prolongation of this fine-tuned initiation phase will ultimately lead to a delayed or incomplete healing such as non-unions which then requires an effect...

Fractures are one of the most frequently occurring traumatic events worldwide. Approximately 10% of fractures lead to bone healing disorders, resulting in strain for affected patients and enormous costs for society. In order to shed light into underlying mechanisms of bone regeneration (habitual or disturbed), and to develop new therapeutic strateg...

Background While osteoarthritis (OA) is the most common joint disease worldwide, rheumatoid arthritis (RA) represents the most common type of autoimmune arthritis. In both diseases, fibroblast-like synoviocytes (FLS), which maintain the structural and dynamic integrity of the joint, have been identified as key drivers of cartilage degradation. FLS...

The outcomes of animal experiments can be influenced by a variety of factors. Thus, precise reporting is necessary to provide reliable and reproducible data. Initiatives such as the ARRIVE guidelines have been enrolled during the last decade to provide a road map for sufficient reporting. To understand the sophisticated process of bone regeneration...

Objective Due to the small size of the murine knee joint, extracting the chondrocyte transcriptome from articular cartilage (AC) is a major technical challenge. In this study, we demonstrate a new pragmatic approach of combining bulk RNA-sequencing (RNA-seq) and single cell (sc)RNA-seq to address this problem. Design We propose a new cutting strat...

After trauma, the formed fracture hematoma within the fracture gap contains all the important components (immune/stem cells, mediators) to initiate bone regeneration immediately. Thus, it is of great importance but also the most susceptible to negative influences. To study the interaction between bone and immune cells within the fracture gap, up-to...

Osteoarthritis (OA) is the most common form of musculoskeletal disease with significant healthcare costs and unmet needs in terms of early diagnosis and treatment. Many of the drugs that have been developed to treat OA failed in phase 2 and phase 3 clinical trials or produced inconclusive and ambiguous results. High throughput omics technologies ar...

Adequate tissue engineered models are required to further understand the (patho)physiological mechanism involved in the destructive processes of cartilage and subchondral bone during rheumatoid arthritis (RA). Therefore, we developed a human in vitro 3D osteochondral tissue model (OTM), mimicking cytokine-induced cellular and matrix-related changes...

25 years after the first Berlin Workshop on Developmental Toxicity this 10th Berlin Workshop aimed to bring together international experts from authorities, academia and industry to consider scientific, methodologic and regulatory aspects in risk assessment of developmental toxicity and to debate alternative strategies in testing developmental effe...

The initial phase of fracture healing decides on success of bone regeneration and is characterized by an inflammatory milieu and low oxygen tension (hypoxia). Negative interference with or prolongation of this fine-tuned initiation phase will ultimately lead to a delayed or incomplete healing such as non-unions which then requires an effective and...

The interaction between the bone and immune cells plays a crucial role in bone pathologies such as disturbed fracture healing. After a trauma, the initially formed fracture hematoma in the fracture gap contains all important components (immune/stem cells, mediators) to directly induce bone regeneration and is therefore of great importance but most...

Understanding the pathophysiological processes of cartilage degradation requires adequate model systems to develop therapeutic strategies towards osteoarthritis (OA). Although different in vitro or in vivo models have been described, further comprehensive approaches are needed to study specific disease aspects. This study aimed to combine in vitro...

Objective: Due to the small size of the murine knee joint, extracting the chondrocyte transcriptome from articular cartilage (AC) is a major technical challenge. In this study, we demonstrate a new and pragmatic approach of combining bulk RNA-sequencing (RNA-seq) and single cell (sc)RNA-seq to address this problem. Design: We propose a new cutting...

Background Approximately 10% of fractures lead to significant fracture healing disorders, with a tendency to further increase due to the aging population. Of note, especially immunosuppressed patients with ongoing inflammation show difficulties in the correct course of fracture healing leading to fracture healing disorders. Most notably, invading i...

Background The bone matrix consists of inorganic and organic components and a variety of specialized cells such as osteoblasts, osteocytes and osteoclasts. The bone-forming osteoblasts are responsible for the production of organic matrix components; they differentiate later into osteocytes which is accompanied by matrix mineralization. Osteoclasts...

Background Our ultimate goal is to study potential drug candidates in an experimental setting of arthritis. Therefore, we aim to develop a valid human in vitro 3D joint model mimicking features of joint inflammation by applying inflammatory conditions namely immune cells and pro-inflammatory cytokines. Our i n vitro 3D joint model consists of diffe...

Both inflammatory diseases like rheumatoid arthritis (RA) and anti-inflammatory treatment of RA with glucocorticoids (GCs) or non-steroidal anti-inflammatory drugs (NSAIDs) negatively influence bone metabolism and fracture healing. Janus kinase (JAK) inhibition with tofacitinib has been demonstrated to act as a potent anti-inflammatory therapeutic...

Macrophages are essential players in the process of fracture healing, acting by remodeling of the extracellular matrix and enabling vascularization. Whilst activated macrophages of M1-like phenotype are present in the initial pro-inflammatory phase of hours to days of fracture healing, an anti-inflammatory M2-like macrophage phenotype is supposed t...

Objective Understanding the pathophysiological processes of osteoarthritis (OA) require adequate model systems. Although different in vitro or in vivo models have been described, further comprehensive approaches are needed to study specific parts of the disease. This study aimed to combine in vitro and in silico modeling to describe cellular and ma...

Adequate analgesia is essential whenever pain might occur in animal experiments. Unfortunately, the selection of suitable analgesics for mice in bone-linked models is limited. Here, we evaluated two analgesics-Tramadol [0.1 mg/ml (T low) vs. 1 mg/ml (T high)] and Buprenorphine (Bup; 0.009 mg/ ml)-after a pre-surgical injection of Buprenorphine, in...

Background Our ultimate goal is to develop a valid human in vitro 3D joint model to simulate the pathogenesis of arthritis. The model consists of different components including an osteogenic and chondrogenic part, the joint space with synovial fluid and the synovial membrane. It contains all involved cell types and thus, to allow interactions betwe...

Fractures in horses–whether simple fractures with just one clean break, or incomplete greenstick with stress fractures, or complications such as shattered bones can all be either minimal or even catastrophic. Thus, improvement in fracture healing is a hallmark in equine orthopedics. The fracture healing process implements a complex sequence of even...

File name: Supporting information. (PDF)

https://www.biorxiv.org/content/10.1101/725317v1

Although several biomaterials for bone regeneration have been developed in the last decades, clinical application of bone morphogenetic protein 2 is clinically only approved when applied on an absorbable bovine collagen I scaffold (ACS) (Helistat; ACS-H). In research, another ACS, namely Lyostypt (ACS-L) is frequently used as a scaffold in bone-lin...

Mesenchymal stem/stromal cells (MSCs) are stem cells of the connective tissue, possess a plastic phenotype, and are able to differentiate into various tissues. Besides their role in tissue regeneration, MSCs perform additional functions as a modulator or inhibitor of immune responses. Due to their pleiotropic function, MSCs have also gained therape...

Background Our ultimate goal is to develop a valid human in vitro 3D joint model to simulate the pathogenesis of arthritis. The in vitro 3D joint model consists of different components including an¹ osteogenic and² chondrogenic part,³ the synovial fluid and⁴ the synovial membrane and contains all involved cell types and thus, to allow interactions...

Bone is a complex tissue with a variety of functions, such as providing mechanical stability for locomotion, protection of the inner organs, mineral homeostasis and haematopoiesis. To fulfil these diverse roles in the human body, bone consists of a multitude of different cells and an extracellular matrix that is mechanically stable, yet flexible at...

Background Immunosuppressed patients with ongoing inflammation experience more often difficulties in the process of fracture healing. Hereby amongst others immunomodulated activation of osteoclasts leads to augmented osteolysis. Most notably numerous cytokines and invading lymphocytes provide an inflammatory environment within the fracture gap, utm...

Background Anti-inflammatory treatment of rheumatoid arthritis (RA) using non-steroidal anti-inflammatory drugs (NSAID) or glucocorticoids (GC) as well as the disease itself, are supposed to negatively influence bone metabolism and healing. However, in vivo models allowing to evaluate therapeutic strategies for patients suffering from delayed bone...

Background Our ultimate goal is to develop a valid in vitro 3D model to simulate the immune mediated pathogenesis of arthritis in order to present an alternative experimental setup for the traditional animal models. Therefore, we work to establish an in vitro simulation of a healthy joint, followed by the depiction of an inflamed arthritic joint to...

Immunologically restricted patients such as those with autoimmune diseases or malignancies often suffer from delayed or insufficient fracture healing. In human fracture hematomas and the surrounding bone marrow obtained from immunologically restricted patients, we analyzed the initial inflammatory phase on cellular and humoral level via flow cytome...

The initial inflammatory phase of fracture healing is of great importance for the clinical outcome. We aimed to develop a detailed time-dependent analysis of the initial fracture hematoma. We analyzed the composition of immune cell subpopulations by flow cytometry and the concentration of cytokines and chemokines by bioplex in 42 samples from human...

Fracture healing is a complex regeneration process which produces new bone tissue without scar formation. However, fracture healing disorders occur in approximately 10% of human patients and cause severe pain and reduced quality of life. Recently, the development of more standardized, sophisticated and commercially available osteosynthesis techniqu...

Background By 2020, osteoarthritis (OA) will be the fourth leading cause of world's most common disabilities as a result of an increasing life expectancy and an aging population. According to the world health organization (WHO), 9.6% of men and 18% of women aged 60 or older suffer from OA worldwide. The main characteristics of OA are the complex in...

Background Rheumatoid arthritis (RA) patients are reported to be often affected by fracture-healing complications not only as a result of osteoporosis. The inflammatory disease itself and anti-rheumatic drugs (e.g. glucocorticoids, GC) are supposed to interfere with the healing process. However, current literature studies reporting the number of af...

Exercise at regular intervals is assumed to have a positive effect on immune functions. Conversely, after spaceflight and under simulated weightlessness (e.g., bed rest), immune functions can be suppressed. We aimed to assess the effects of simulated weightlessness (Second Berlin BedRest Study; BBR2-2) on immunological parameters and to investigate...

Background Gene therapy seems promising to achieve long-term remedy for osteoarthritis (OA). However, there are several risks of adverse reactions especially when using CMV-controlled expression. To provide a safe application, we focused on the expression of therapeutic cytokines, e.g. IL-4, in a disease-responsive manner by use of the previously c...

Three-dimensional scaffold-free tissue constructs represent a special kind of transplants in tissue engineering. The fzmb developed a method (SFCT-technology) to produce three-dimensional scaffold-free cartilage transplants (SFCT) out of differentiated chondrocytes in monolayer, based on the application of intermitted mechanical stimulation to cell...

Unlabelled: PURPOSE/AIM OF THE STUDY: Chlorhexidine and polyhexanide are frequently used antiseptics in clinical practice and have a broad antimicrobial range. Both antiseptics are helpful medical agents for septic wound treatment with a high potential for defeating joint infections. Their effect on human osteoblasts has, so far, not been sufficie...

Background Rheumatoid arthritis patients exhibit a high prevalence of osteoporosis and bone fractures. Furthermore, these patients are reported to be more often affected by delayed or impaired fracture healing. The inflammatory disease itself but also antirheumatic drugs are suspected to contribute to these complications. Recent animal studies sugg...

Background Rheumatic diseases such as osteoarthritis (OA) and rheumatoid arthritis (RA) rank among the most common musculoskeletal disorders around the globe accounting for marked loss of life quality, considerable disabilities and financial impact on society. However, an effective causal therapy still remains elusive to provide a long-term remedy....

Background Glucocorticoids (GC) represent most frequently-used anti-inflammatory drugs in rheumatology. However, especially if given at higher dosages for a longer time, they have the potential to induce adverse effects such as GC-induced delayed bone regeneration and osteoporosis. Several studies have demonstrated the negative influence of anti-in...

Glucocorticoids represent highly effective modulators of the immune system with antiinflammatory and immunosuppressive characteristics. Since their introduction into clinical medicine, glucocorticoids have been widely used in the treatment of several different diseases. Their application ranges from very low to very high doses. In spite of their ma...

Zusammenfassung Glukokortikoide sind potente Modulatoren des Immunsystems mit antientzündlicher und immunsuppressiver Wirkung. Seit ihrer Einführung in die klinische Medizin werden Glukokortikoide sehr breit angewandt und kommen sowohl in sehr niedrigen bis sehr hohen Dosierungen zum Einsatz. Trotz der vielen positiven Eigenschaften der Glukokortik...

A peptide-based enzyme-linked immunosorbent assay (ELISA) for discrimination between serological responses to equine herpesvirus type 1 (EHV-1) and 4 (EHV-4) was developed. Three and four peptides for EHV-1 and EHV-4, respectively, were designed and studied initially in the ELISA using sera from foals infected experimentally. The most promising pep...