Chondrocyte cell death and intracellular distribution of COMP and type IX collagen in the pseudoachondroplasia growth plate
Bibliographic record
Abstract
Cartilage oligomeric matrix protein (COMP) is a large extracellular matrix protein expressed in cartilage, ligament and tendon. Mutations in the COMP gene cause two dominantly inherited skeletal dysplasias, pseudoachondroplasia (PSACH) and Multiple Epiphyseal Dysplasia (MED/EDM1). We report on a novel point mutation D511Y in the seventh calcium-binding repeat of the COMP gene and the resulting iliac crest growth plate pathology. The PSACH iliac crest growth plate is comprised of a large region of resting chondrocytes above a narrow region composed of clusters of disorganized proliferative and hypertrophic chondrocytes. Chondrocytes in all zones show massive intracellular retention of COMP and the surrounding extracellular matrix is deficient in COMP. Moreover, the 511Y COMP mutation selectively affects type IX collagen as little is found in the growth plate matrix whereas type II collagen and aggrecan are abundant in the matrix. Chondrocyte remnants are observed in the chondrocyte clusters and dead cells are found throughout the growth plate. Apoptosis studies demonstrate an unusual pattern of TUNEL staining in the PSACH chondrocytes compared to the control growth plate. These in vivo findings support our previous observation that retention of COMP leads to chondrocyte death. These results also add to the increasing evidence that PSACH and EDM1 are rER storage diseases and that impaired linear growth and joint erosion are caused by the disruptive effect of massive amounts of COMP within the chondrocytes.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".