SARS-CoV-2 cell entry gene ACE2 expression in immune cells that infiltrate the placenta in infection-associated preterm birth
Bibliographic record
Abstract
Abstract COVID-19 infection during pregnancy is associated with an increased incidence of preterm birth but neonatal infection is rare. We assessed pathways by which SARS-CoV-2 could access the placenta and contribute to fetal transmission. Placentas from pregnancies complicated with chorioamnionitis (ChA), exhibited increased expression of ACE2 mRNA. Treatment of 2 nd trimester placental explants with LPS, induced an acute increase in cytokine expression followed by ACE2 mRNA. Placental ACE2 protein localized to syncytiotrophoblast, in fetal blood vessels and M1/M2 macrophage and neutrophils within the villous stroma. Increased numbers of M1 macrophage and neutrophils were present in the placenta of ChA pregnancies. Maternal peripheral immune cells (mainly granulocytes and monocytes) express the ACE2 mRNA and protein. These data suggest that in COVID19 positive pregnancies complicated by ChA, ACE2 positive immune cells have the potential to traffic SARS-CoV-2 virus to the placenta and increase the risk of vertical transmission to the placenta/fetus.
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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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.001 |
| Research integrity | 0.001 | 0.002 |
| 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".