Postdoctoral Researcher / Postdoctoral Researcheress

Postdoc Position in Multiphoton Intravital Imaging

100%, Zurich, fixed-term

The Laboratory for Bone Biomechanics (LBB) at the Institute for Biomechanics at ETH Zurich is offering a Postdoc position in multiphoton intravital imaging of heterotopic ossification and bone fracture healing. This role is part of the SNSF Sinergia project SLIHI4BONE (Nr. 213520; project start 01.04.2023; collaboration partners: M. Bohner, RMS Foundation, Bettlach; R. Müller, ETH Zurich; E. Wehrle, ARI Davos). The project focuses on a newly proposed mechanism that explains the formation of bone in soft tissue, known as heterotopic ossification (doi:10.1016/j.mattod.2018.10.036). This study aims to assess the validity of this mechanism, which suggests that tissue mineralization may provoke a sustained local ionic homeostatic imbalance (SLIHI) and a local decrease in extracellular calcium that could modulate inflammation to trigger bone formation. Ultimately, the project seeks to leverage this understanding for enhanced healing of large bone defects.

Project Background

Heterotopic ossification (HO) is a common and often debilitating condition characterized by the formation of mature bone in soft tissues. The mechanisms underlying HO remain poorly understood, and existing therapies to prevent and treat this condition have shown limited efficacy, sometimes necessitating surgical removal of the aberrantly formed bone. The process involves an osteoinductive mechanism during which stem cells differentiate into bone cells—an essential capability for treating large bone defects. Current strategies include the implantation of bone morphogenetic proteins (BMPs), although concerns regarding their safety persist. Alternatively, osteoinductive bone graft substitutes have demonstrated low potency, and their mechanisms are still under debate. Demonstrating the crucial role of low extracellular calcium concentrations in triggering bone formation and understanding this process better could pave the way for designing more effective osteoinductive substitutes and improving treatments for compromised bone healing.

Project Team and Setup: The project adopts a multidisciplinary collaborative approach, supported by a team of three PhD students specializing in material science, advanced *in vivo* imaging, and *in vivo* molecular biology. The focal point of the Postdoc position (LBB, ETH Zurich) involves further developing our multiphoton intravital imaging technology. This team structure will enable the design of calcium phosphate materials with controlled architecture and composition while assessing their mineralization rates both *in vitro* and *in vivo*. The level of extracellular calcium and the surrounding tissue response will be monitored using multimodal approaches, including time-lapsed *in vivo* imaging, multiphoton intravital microscopy, spatial transcriptomics, and proteomics.

Job Description

For the multiphoton intravital imaging work package within SLIHI4BONE, we are looking for a motivated Postdoc to join the Institute for Biomechanics at ETH Zurich. You will have the opportunity to closely collaborate with our Sinergia partners at RMS Foundation and ARI Davos:

• Develop intravital imaging protocols for HO and impaired bone healing using time-lapsed micro-computed tomography and multiphoton microscopy.
• Extend intravital imaging technology to include ratiometric imaging for quantifying bone marrow interstitial pH and calcium concentrations.
• Provide imaging support for *in vivo* experiments.

Profile

• PhD degree in physics or biophysics.
• Experience in intravital imaging, demonstrated by first-author publications, is required.
• Previous experience with ratiometric imaging is advantageous.
• Experience with *in vivo* animal models is also advantageous.
• Excellent communication skills in English (both oral and written) are essential.
• High motivation and a strong interest in skeletal research, along with resilience in facing challenges.
• Ability to solve complex tasks independently.
• Familiarity with a cross-cultural/interdisciplinary environment is advantageous.

Workplace

ETH Zurich is one of the world’s leading universities specializing in science and technology. We are renowned for our excellent education, cutting-edge research, and the direct application of new knowledge to societal challenges. Located in the heart of Europe, we foster connections worldwide, striving to develop solutions for global challenges.

We Offer

• An impactful job: Become part of ETH Zurich, which supports your professional development while contributing positively to society.
• A dynamic and diverse work environment within innovative organizations.
• Collaboration in a highly committed multidisciplinary team.
• Regular meetings and close cooperation with Sinergia project partners.
• Numerous benefits, including public transport season tickets, car sharing, a wide range of sports offered by ASVZ, childcare, and attractive pension benefits.

Diversity and Sustainability

In line with our values, ETH Zurich fosters an inclusive culture. We promote equal opportunity, value diversity, and nurture a working and learning environment that respects the rights and dignity of all staff and students. For more details, visit our Equal Opportunities and Diversity website. Sustainability is a core value; we are committed to working toward a climate-neutral future.

Interested?

If this opportunity excites you, apply online using the form below. Please ensure that your application includes:

• Motivation letter
• Curriculum Vitae
• Publication list
• Names and contact details of two academic references

Only applications matching the job profile will be considered.

For further information about the Laboratory for Bone Biomechanics, please visit our website. Inquiries regarding the position should be directed to Prof. Dr. Ralph Müller at ram@ethz.ch (no applications).