The evolution of affinity maturation: Germinal center-like cell aggregates in fish (81.16)
Bibliographic record
Abstract
Abstract Compared with mammals, fish and amphibians have a limited antibody affinity maturation response, an outcome attributed to their lacking distinguishable germinal centres. There is evidence of Ig hypermutation and antigen driven selection, and as such we’d anticipate some sort of germinal center (GC)-like structures, perhaps akin to the varied GC-like cell aggregates observed in different human autoimmune disease. To establish whether fish have GC-like cell aggregates we did in situ hybridization and laser capture microscopy coupled with gene expression analyses on spleen sections of BSA immunized channel catfish. AID expressing cells were found predominantly in tight association with so called melano-macrophage centers or clusters (MMCs). Melano-macrophages have previously been noted for their ability to capture and retain whole antigen and thus had been proposed to be functionally analogous to follicular dendritic cells. Though far smaller than mammalian GCs the fish MMCs also contain CD4 expressing cells and a few flanking plasma cells. However TUNEL assays did not reveal the expected numbers of surrounding apoptotic cells. While there are alternative theories as to the function of these cell aggregates we are proposing that they are primitive germinal centers. Funded by the National Science and Engineering Research Council - Canada
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 machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 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 | 0.001 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.001 |
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 source (direct Gemma or distilled Codex), 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".