PIPages
Labs

Jennifer Puetzer

Virginia Commonwealth University, VA·Biomedical Engineering·Early-career

Collagen fibers give tendons, ligaments and menisci (the cartilage pads in the knee) their strength. Cells build these fibers in levels, from fibrils a few nanometers wide up to larger fibers and bundles called fascicles.

Fields

Biomedical Engineering

Physiology

Engineering

Topics

collagen

extracellular matrix

mechanobiology

Grants
2 known grants, through Feb 2028

What they work on

  1. Evaluate how focal adhesion kinase (FAK), a contraction-signaling enzyme, and the stretch-activated ion channels TRPV4 and Piezo1 each contribute to hierarchical collagen fiber formation by ligament fibroblasts in static culture, by inhibiting or activating each pathway.
  2. Determine how the roles of FAK, TRPV4 and Piezo1 change under dynamic mechanical stimulation, measuring collagen organization at fibril, fiber and fascicle scales, proteoglycan accumulation and collagen crosslinking.
  3. Test whether slow strains of 0.1–1 mm per day, mimicking postnatal growth, drive native-like hierarchical collagen organization and matrix maturation in engineered ligament grown in the lab's culture system.
  4. Test whether rapid intermittent cyclic strains of 1–2 mm per second that mimic muscle activity, alone and combined with slow growth strains, produce stronger engineered ligament, assessed by collagen organization, matrix composition and mechanics.

More about the research

The fibers grow bigger and stronger as mechanical demands increase. After an injury, these fibers do not regrow, and engineered tissue replacements lack them, so repair options for torn tissues are poor. The lab's long-term goal is to understand how cells build collagen fibers, so that functional replacements can be engineered and repair can be driven inside the body. Both projects use a culture system the lab developed, which guides ligament cells to produce native-size fibrils, fibers and fascicles over six weeks.

Why it matters

Torn tendons, ligaments and menisci heal poorly because their collagen fibers do not regenerate. Learning how mechanical cues drive fiber formation could help engineer stronger ligament replacements. It could also point to therapeutic targets such as FAK, TRPV4 or Piezo1 for regenerating fibers and reducing scarring, and could inform rehabilitation protocols that restore function after musculoskeletal injuries.

Known grants

From NIH and NSF research grants. Labs often have other funding we can't see.

Unraveling the Mechanism of Mechanotransduction in Hierarchical Collagen Fiber Formation

NIH · May 2023 – Feb 2028

CAREER: Driving Hierarchical Collagen Fiber Maturation with Mechanobiology

NSF · May 2021 – Apr 2027

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The school

Virginia Commonwealth University: 19 labs on PI Pages, $524M a year on research, 438 research doctorates a year.

More about Virginia Commonwealth University

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