CD40/CD40 Homodimers Are Required for CD40-induced Phosphatidylinositol 3-Kinase-dependent Expression of B7.2 by Human B Lymphocytes
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
Preformed CD40/CD40 homodimers were initially observed on human Burkitt lymphoma cell lines, normal B cells, and transitional bladder carcinoma cell lines. However, the nature and the biological relevance of these homodimers have not yet been investigated. In the present study, we demonstrated that Epstein-Barr virus-transformed B cells and CD40-transfected HEK 293 cells constitutively expressed disulfide-linked CD40/CD40 homodimers at low levels. Oligomerization of CD40 leads to a rapid and significant increase in the disulfide-linked CD40/CD40 homodimer formation, a response that could be prevented using a thiol-alkylating agent. Formation of CD40/CD40 homodimers was found to be absolutely required for CD40-mediated activation of phosphatidylinositol 3-kinase, which, in turn regulated B7.2 expression. In contrast, CD40 monomers provided the minimal signal emerging from CD40, activating p38 MAP kinase and inducing homotypic B cell adhesion. CD40/CD40 homodimer formation was totally independent of TRAF1/2/3/5 associations with the threonine at position 254 in the cytoplasmic tail of the CD40 molecules. This finding may be vital to better understanding the molecular mechanisms that govern cell signaling triggered by CD40/CD154 interactions.
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.
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 | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.001 | 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 it