Evidence for the presence of a low-mass β1 integrin on the cell surface
Bibliographic record
Abstract
Although the cell line K562 reportedly expresses a single species of beta1 integrin, alpha5beta1, surface staining with monoclonal antibodies JB1A, 12G10 and B3B11 to the beta1 chain clearly demonstrated differences in the expression levels of the epitopes detected by these antibodies. The present studies were initiated to determine the basis for this molecular heterogeneity in the integrins. Cross-linking of surface integrins with B3B11 caused their selective aggregation. This distribution was similar to that observed for the alpha5 chain. In contrast, cross-linking the beta1 chains with 12G10 did not cause codistribution of alpha5, suggesting that these two species were not associated on the cell surface. Immunoprecipitates of the surface integrins of K562 cells indicated the presence of 120 and 140 kDa forms of the beta1 chain which were detected by 12G10 and B3B11, respectively. Immunological, biochemical and mass spectrometric analysis of K562 surface integrins also failed to demonstrate the presence of any alpha chain in association with the 120 kDa species of beta1 of K562 cells. Treatment of the two forms of beta1 with PGNase reduced their masses to approximately 90 kDa, suggesting that N-glycosylation was responsible for the mass differences. Collectively, these results provide evidence for a novel species of beta1 on the cell surface, which does not appear to be associated with any alpha chain. The data also suggest that differences in glycosylation may be involved in defining the association between the integrin alpha and beta chains and the functional properties of these integrins.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.005 | 0.003 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| 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".