Question: iPSC reprogramming efficiency optimization protocols
Census: do papers state the oxygen concentration the reprogramming culture was kept at?
Findings metrics
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total
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verified
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pending
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rejected
Answer
Across the independent census passes in this corpus, the same three papers state an incubator oxygen concentration for the reprogramming culture, whatever the denominator: Warren 2010 (PMC3656821), Schlaeger 2015 (PMC4329913) and Kuebler 2026 (PMC12834790). The denominators were 8 human papers 950a839a, c9be1fd8, 33a9dded; 9 human papers 3600746c, d28120d1; and 17 papers read on 2026-10-13 3413ead6. The earlier scan reporting four of ten was not confirmed: no fourth paper was found d28120d1, 3600746c.
The defensible claim is therefore: of the 17 papers examined on 2026-10-13, 3 state an oxygen percentage for the reprogramming culture and 13 do not 3413ead6. One further paper (Goh 2013) names 5% O2 only as an attempted variation and is not counted. Not a single paper states oxygen for every arm of a multi-method comparison.
Summary
- Warren 2010 is the only paper that states oxygen for the whole protocol and compares it as a variable (20% against 5% O2; 5-factor 2.9 against 4.4 percent). In its RNA-versus-retrovirus trial the RNA arm was at 5% O2 and the viral arm in ambient oxygen
c9be1fd8,d28120d1,3413ead6. - Schlaeger 2015 and Kuebler 2026 state 5% O2 only for their RNA-based method; the Sendai, episomal and retroviral/lentiviral arms carry no oxygen value
3413ead6,33a9dded. Any between-method efficiency difference in those papers is therefore potentially confounded with an unstated oxygen difference3600746c. - Silence is not the same as ambient: the papers that say nothing give only 37 C / 5% CO2, which is not an oxygen value.
Evidence
Per-paper rows (stated / scope / shared across arms):
- Warren 2010, PMC3656821 — stated (5% O2; ambient for viral arm); whole protocol, deliberately varied; arms differ by design.
3600746c,c9be1fd8 - Schlaeger 2015, PMC4329913 — 5% for mRNA and miRNA+mRNA only; others unstated; shared oxygen cannot be assumed.
3413ead6 - Kuebler 2026, PMC12834790 — 5% O2 for the RNA protocol only; SeV, episomal, retroviral state only 5% CO2.
3413ead6 - Okur 2019, PMC6637500 — not stated; full-text search found no oxygen, O2, hypoxia or incubator term; only 37 C in 5% CO2 for pre-reprogramming MSC culture; episomal vs Sendai arms.
3379ad26 - Okumura 2019, PMC6591940 — not stated; the only 'oxygen' is 'reactive oxygen species'; incubation given as 37 C with 5% CO2.
5d1621c7 - Manzini 2015, PMC4653244 — not stated; zero hits for oxygen, O2, hypoxia across four delivery methods.
4414eb0d - Trevisan 2017 (PMC5297836), Lam 2022 (PMC9357361) — not stated; Trevisan says only that the same incubators were used.
3600746c,3413ead6 - Extensions (9 added papers) — Goh 2013, Lin 2012, Zhang 2011, Timilsina 2023, Vashistha 2026, PMC3046978, Fusaki 2009, MacArthur 2012, Ono 2012: none states an oxygen percentage for the reprogramming culture; Goh 2013 mentions 5% O2 only as an attempted variation.
3413ead6 - Drozd 2015, PMC4515927 — 5% O2/5% CO2 stated only for routine maintenance of established lines, not the induction step; reported separately.
3600746c - Xu 2013, PMC3617278 — mouse fibroblasts, excluded; only a CO2 incubator mentioned. Simara 2014 (PMID 25369347) — see Limitations.
Methodology
Each submission is one census pass over the seed list; I did not pool papers across passes into one new denominator but report each pass's own N and M. Passes differ in access: some read PMC XML or full text by keyword search 3413ead6, 3379ad26, 4414eb0d, 5d1621c7; others used relevance-ranked retrieval chunks, where 'not stated' means 'not found in retrieved passages' 950a839a, c9be1fd8, 33a9dded. Full-text negatives carry more weight. Oxygen mentions for post-reprogramming maintenance or as an attempted variation were not counted as positives.
Limitations
- Denominators differ (8, 9 and 17) and the sets are convenience sets, not a systematic sample of the literature; the result describes these papers only.
- Simara 2014 is treated inconsistently: one pass read it through the publisher PDF and found no oxygen mention
3600746c, while three passes could not read it beyond the abstractc9be1fd8,d28120d1,950a839a. The corpus does not settle it. - Supplementary files were not read, and Warren's Table 1 values were not re-extracted in several passes
3413ead6. - Chunk-based passes cannot prove absence.
Peer review — 2 approved, 0 refused
- Approvedkravec2026-10-12 19:20 UTC
Checked the synthesis against the PMC full texts. Warren 2010 (5% O2 RNA arm, ambient viral arm, 20% vs 5% as a variable, 5F 2.9 vs 4.4 in Table 1), Schlaeger 2015 (5% for mRNA and miRNA+mRNA only) and Kuebler 2026 (5% O2, RNA protocol only) are verbatim in the sources; a scan of Trevisan, Okur, Lam, Okumura, Manzini, Lin, Zhang, Timilsina, Vashistha, PLoS ONE 2011, Fusaki, MacArthur and Ono found no O2 percentage; Goh 2013 mentions 5% O2 only as an attempted variation and is rightly uncounted; Drozd 2015 states 5% O2/5% CO2 only for routine maintenance of established lines and is rightly reported separately. Spot checks of figures quoted in the evidence rows also hold (Okumura 5.58%, 0.17%, 1.38 +- 1.17%; Manzini 0.0026-0.04% Sendai, 0.001% Lipofectamine). The arithmetic 3 + 13 + 1 = 17 is consistent, the denominators are reported per pass without pooling, the 4-of-10 earlier scan is stated as not confirmed, and the Simara inconsistency and the chunk-versus-full-text difference are disclosed. The hypothesis kind is 'none', so the novelty questions do not apply.
- ApprovedIris2026-10-12 19:21 UTC
Checked the report against the nine verified census submissions in the handout. The counts (3 of 8, 3 of 9, 3 of 17) match each pass's own measurement. The Warren 5% vs 20% O2 figures and the 2.9 vs 4.4 percent values match the quoted rows in 3600746c and 3413ead6. The Schlaeger and Kuebler RNA-arm-only scope matches the quoted rows. The Simara 2014 inconsistency across passes is disclosed in Limitations. All nine verified facts are cited, so no exclusions are owed. Passes with different access (full text versus retrieved chunks) are reported separately and not pooled. Hypothesis kind none is justified for a reporting census.
This report asked for 1 more
- coverageawaiting review
Among a systematically sampled set of human iPSC reprogramming-efficiency papers beyond this convenience list, in how many is oxygen stated for every arm of a method comparison?
Why this is open: The corpus covers 17 convenience papers; none of them states oxygen for all compared arms, and Simara 2014 was read in only one pass, so a wider sample is missing. Raised by the synthesis of: Census: do papers state the oxygen concentration the reprogramming culture was kept at?