Peek behind the paper: mapping proteins to bioprint functional ovaries
In this interview with Monica Laronda (Ann & Robert H. Lurie Children's Hospital of Chicago; IL, USA), 3DMedNet takes a closer look at how mapping porcine proteins could be an influential step towards developing a viable bioink for bioprinting functional ovaries.
I am Monica Laronda, Warren and Eloise Scholar for the Stanley Manne Children’s Research Institute at the Ann & Robert H. Lurie Children’s Hospital and Assistant Professor in Pediatrics at Northwestern University (IL, USA). I received my PhD in life sciences while studying spermatogonial stem cell differentiation in Larry Jameson’s Lab and trained in ovarian biology and oncofertility as a postdoc in Teresa Woodruff’s lab, both at Northwestern. I am Director of Research for the Fertility & Hormone Preservation & Restoration Program at Lurie Children’s. Interacting with patients and families and understanding the clinical methods and current clinical practice with my partner, Erin Rowell (Medical Director, FHPR), gives me the drive to want to improve these options for patients and the ability to translate our successes in the lab.
Could you please tell us about the project covered in the recent 3DMedNet news piece, as well as any other related projects you may currently be working on?
I have previously published on creating a 3D-printed bioprosthetic ovary that was successful in restoring fertility and hormone function in mice whose ovaries were removed. This scaffold was printed from gelatin. The lifespan of any ovarian transplant to supply hormones and eggs is dependent on the number of primordial follicles that remain quiescent.
We are interested in translating this into the clinic and wanted to take a step back and understand the scaffold proteins that provide biochemical and physical cues to these primordial follicles, which are the functional units of the ovary and contain a centralized oocyte (potential egg cell) supported and surrounded by hormone producing cells. In this paper, we mapped the matrisome proteins across a porcine ovary.
We achieved this by slicing the porcine ovary in 0.5 mm slices in two different anatomical directions, enriching for matrisome proteins and performing proteomics analysis on each slice. A new analytical pipeline was used to interpret this information into a special map. We compared protein expression across the ovary and specifically compared the cortical region, where the quiescent follicles reside, and the medullary region, where most growing follicles are.
How do you envision your work translating to the medical field? How could protein mapping lead to bioprinting functional ovaries?
The protein mapping and comparison of different regions within the ovary has revealed some candidate proteins that may be important for maintaining follicle quiescence. We are interrogating the pathways of these candidate proteins in situ to determine if their perturbation leads to follicle activation. At the same time, we are making different 3D-printable inks from some of these protein combinations. I envision that a scaffold with the same architecture that we have defined as integral for oocyte survival and growth will be created with a new ink that appropriately controls follicle activation through physical and biochemical cues provided by specific matrisome proteins. These scaffolds will be seeded with the patient’s follicles that they have cryopreserved prior to a cancer treatment.
The scaffold with the patient’s follicles – or bioprosthetic ovary – will then be transplanted as a strip on the remaining ovary, that has lost its function, or in a similar peritoneal location to restore long term fertility and hormone function.
What challenges have you faced in mapping proteins with the goal of engineering a biological scaffold in mind?
The analysis was a little challenging and Nathaniel Henning (Ann & Robert H. Lurie Children’s Hospital of Chicago and Northwestern University) worked with Richard DeLuc (Northwestern University), authors on the paper, to develop tools that could make sense of the proteomics information to create a map. We are hoping that the pipeline established with this research will help others to map the matrisome proteins in their favorite organs.
What challenges associated with reproductive health may your research help to overcome?
The current methods for fertility preservation for patients that do not yet make eggs or have other indications that prevent them from being able to bank eggs, is to remove one ovary and cryopreserve the tissue in pieces. These tissue pieces can then be transplanted back once the patient has lost ovarian function. This has results in hundreds of births, world-wide and temporary restoration of ovarian hormones.
This process could be improved for all patients, but we hope to be able to remove the risk of reintroducing cancer cells by creating a platform that supports primordial follicles that have been isolated away from disease and putting them in an environment that can support function for more years.
A challenge for some patients is that they may not have any or enough ovarian follicles, as they are a finite resource.
A 3D-printed scaffold with the right compartmentalization could be used to create an ovary with stem cell derived follicles when this technology is developed.
Where do you see medical 3D printing in 5–10 years time? How could research such as yours be applied to this?
I think that to advance regenerative medicine through 3D printing, more biologists and clinical partners need to be considered critical members of the team. I interact with many engineers who come across problems with their technology that seem obvious from my standpoint as an expert in ovarian biology. Additionally, having knowledge of how this technology will be used in the clinic is also essential to designing a functional object that a patient would want and a physician would use.
I think that if more collaborations are developed, then the future for 3D printing for medical purposes is bright.