# EXTRACELLULAR COMPARTMENTS: TENDON DEVELOPMENT & REPAIR

> **NIH NIH R01** · UNIV OF MED/DENT NJ-R W JOHNSON MED SCH · 1987 · $127,714

## Abstract

The manner in which extracellular matrix components are assembled into a
tissue specific structure with a unique function will be investigated
during development and repair of the chick embryo tendon.

Synthesis and deposition of collagen involves multiple steps beginning in
the cell and continuing into extracellular compartments.  The passage of
matrix components from intracellular compartments, where synthesis and
early aggregation occur, to extracellular compartments, where further
biochemical processing and deposition take place, is a spatial, temporal
and functional continuum.  The structural study of these compartments, in
situ, requires a three dimensional appreciation of their topography.  The
functions of these various compartments are defined by their content and
assembly related activity, and their study, in situ, will require
autoradiography and immunocytochemistry.

The structure of the extracellular compartments formed by the tendon cell
surface during collagen fibril, bundle and macro-aggregate formation will
be studied by conventional (60 kv) and intermediate voltage (120 kv)
transmission electron microscopy (IVEM), stereoscopic examinations of 0.5
Mum sections, and computer assisted three dimensional reconstruction of 0.5
Mum serial sections.

Extracellular compartments control focal regions of the extracellular space
for such biochemical steps as procollagen processing, covalent
cross-linking, and also serve to define the actual sites of matrix
deposition.  The temporal and spatial organization of collagen fibrils,
bundles and larger aggregates in the extracellular space will be studied
using pulse-chase autoradiography to define the pathway of type I collagen
through the extracellular compartments.  The unique, in situ, biochemical
character of each of the compartments will be studied.  Specific antibodies
and immunoelectron microscopy will be used to identify structures and/or
enzymes specific for the processing and assembly of type I collagen, viz.
amino and carboxy extension peptides of procollagen; the carboxy terminal
processing enzyme; lysyl oxidase, the cross-linking enzyme; and cell
surface collagen binding proteins.

These studies characterizing the structural and biochemical
compartmentalization of the extracellular space will contribute to our
understanding of the mechanisms by which the precise collagen architecture
associated with tissue integrity are controlled during development, growth,
injury and repair.

## Key facts

- **NIH application ID:** 3157867
- **Project number:** 5R01AR037003-02
- **Recipient organization:** UNIV OF MED/DENT NJ-R W JOHNSON MED SCH
- **Principal Investigator:** DAVID E BIRK
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1987
- **Award amount:** $127,714
- **Award type:** 5
- **Project period:** 1986-04-01 → 1989-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3157867

## Citation

> US National Institutes of Health, RePORTER application 3157867, EXTRACELLULAR COMPARTMENTS: TENDON DEVELOPMENT & REPAIR (5R01AR037003-02). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/3157867. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*