{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T04:33:03Z","timestamp":1777350783695,"version":"3.51.4"},"update-to":[{"DOI":"10.12688\/f1000research.163800.1","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T00:00:00Z","timestamp":1777334400000}},{"DOI":"10.12688\/f1000research.163800.2","type":"new_version","label":"New version","source":"publisher","updated":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T00:00:00Z","timestamp":1777334400000}}],"reference-count":18,"publisher":"F1000 Research Ltd","license":[{"start":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T00:00:00Z","timestamp":1777334400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"New Frontiers in Research Fund"},{"name":"Sepsis Canada"}],"content-domain":{"domain":["f1000research.com"],"crossmark-restriction":false},"short-container-title":["F1000Res"],"abstract":"<ns7:p>Background Sepsis remains a leading cause of mortality in critical care. Despite extensive preclinical research on sepsis pathophysiology, the development of effective therapies has been largely unsuccessful. Key obstacles include limited construct validity of animal models, insufficient methodological rigor and the lack of collaborative frameworks akin to clinical trials. These issues plague not only sepsis research, but preclinical research in general. The National Preclinical Sepsis Platform (NPSP), an interdisciplinary network under Sepsis Canada, addresses these challenges in sepsis research through multilaboratory, randomized, controlled preclinical studies. NPSP-01 will establish baseline conditions for future investigations using an acute fecal-induced peritonitis model of sepsis. Methods This randomized, controlled study will evaluate the effect of standard sepsis therapy in a mouse model of sepsis across six centres. Interlaboratory variability and the interaction of biological sex on outcomes will also be examined. C57BL\/6 mice of both sexes will be randomized into sham (healthy control) + treatment, sepsis, or sepsis + treatment groups. Sepsis will be induced via intraperitoneal injection of fecal slurry, while sham mice will receive vehicle control. Antibiotics and fluids will be administered to treatment groups at 4 hours post-induction, and mice with be humanely killed at 8 hours post-induction. The primary outcome is plasma interleukin-6 levels. Secondary outcomes include biological (blood gas and chemistry, white blood cell count, bacterial load), clinical (body weight, core temperature, sepsis score, mortality as measured by surrogate humane endpoints), and feasibility measures. Conclusions NPSP-01 will be the first multilaboratory study of sepsis and represents a shift in preclinical critical illness research, mirroring the rigor of clinical multicenter trials. By addressing procedural standardization, interlaboratory variability, and sex-based differences, this study aims to enhance the reliability and translational relevance of preclinical findings. The outcomes of NPSP-01 will establish foundational data for future investigations and provide a roadmap for rigorous collaborative preclinical studies to accelerate the evaluation of novel sepsis therapies. Registration PreclinicalTrials.eu PCTE0000552 Protocol Version 1.0, October 21, 2024<\/ns7:p>","DOI":"10.12688\/f1000research.163800.3","type":"journal-article","created":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T03:39:08Z","timestamp":1777347548000},"page":"472","update-policy":"https:\/\/doi.org\/10.12688\/f1000research.crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Assessing the effects of fluids and antibiotics in an acute murine model of sepsis: study protocol for the National Preclinical Sepsis Platform-01 (NPSP-01) Study"],"prefix":"10.12688","volume":"14","author":[{"given":"Forough","family":"Jahandideh","sequence":"first","affiliation":[{"name":"Blueprint Translational Research Group, Acute Care Research and Methods and Implementation Research Programs Ottawa ON Ottawa Hospital Research Institute"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Asher A.","family":"Mendelson","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Section of Critical Care Winnipeg Manitoba University of Manitoba"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Patricia C.","family":"Liaw","sequence":"additional","affiliation":[{"name":"Department of Medicine Hamilton Ontario McMaster University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sean E.","family":"Gill","sequence":"additional","affiliation":[{"name":"Department of Physiology and Pharmacology London Ontario Western University Schulich School of Medicine & Dentistry"},{"name":"Division of Respirology London Ontario Western University Schulich School of Medicine & Dentistry"},{"name":"Centre for Critical Illness Research London ON London Health Sciences Centre Research Institute"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stephane","family":"Bourque","sequence":"additional","affiliation":[{"name":"Department of 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Anesthesiology and Pain Medicine Edmonton Alberta University of Alberta"},{"name":"Department of Critical Care Medicine Edmonton AB Royal Alexandra Hospital, University of Alberta"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Janet","family":"Sunohara- Neilson","sequence":"additional","affiliation":[{"name":"Animal care services, Office of Research Guelph ON University of Guelph"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Doreen","family":"Engelberts","sequence":"additional","affiliation":[{"name":"Blueprint Translational Research Group, Acute Care Research and Methods and Implementation Research Programs Ottawa ON Ottawa Hospital Research Institute"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David","family":"Sontag","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, Section of Critical Care Winnipeg Manitoba University of Manitoba"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dhruva J.","family":"Dwivedi","sequence":"additional","affiliation":[{"name":"Department of Medicine Hamilton Ontario McMaster University"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ian-Ling","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Critical Care Medicine Calgary Alberta University of Calgary Cumming School of Medicine"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Onon","family":"Batnyam","sequence":"additional","affiliation":[{"name":"Centre for Critical Illness Research London ON London Health Sciences Centre Research Institute"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kashimbi","family":"Mbuta","sequence":"additional","affiliation":[{"name":"Department of Anesthesiology and Pain Medicine Edmonton Alberta University of Alberta"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Dean A.","family":"Fergusson","sequence":"additional","affiliation":[{"name":"Blueprint Translational Research Group, Acute Care Research and Methods and Implementation Research Programs Ottawa ON Ottawa Hospital Research Institute"},{"name":"Methods and Implementation Research Program Ottawa Ontario Ottawa Hospital Research Institute"},{"name":"Faculty of Medicine Ottawa Ontario University of Ottawa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3978-8961","authenticated-orcid":false,"given":"Monica","family":"Taljaard","sequence":"additional","affiliation":[{"name":"Methods and Implementation Research Program Ottawa Ontario Ottawa Hospital Research Institute"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Braedon","family":"McDonald","sequence":"additional","affiliation":[{"name":"Department of Critical Care Medicine Calgary Alberta University of Calgary Cumming School of 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J."},{"key":"ref18","doi-asserted-by":"publisher","DOI":"10.17605\/OSF.IO\/R5G7Y","article-title":"National Preclinical Sepsis Platform-01 (NPSP-01).","author":"M Lalu","year":"2025, April 10"}],"container-title":["F1000Research"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/f1000research.com\/articles\/14-472\/v3\/xml","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/f1000research.com\/articles\/14-472\/v3\/pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/f1000research.com\/articles\/14-472\/v3\/iparadigms","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T03:39:11Z","timestamp":1777347551000},"score":1,"resource":{"primary":{"URL":"https:\/\/f1000research.com\/articles\/14-472\/v3"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,4,28]]},"references-count":18,"URL":"https:\/\/doi.org\/10.12688\/f1000research.163800.3","relation":{"has-version":[{"id-type":"doi","id":"10.12688\/f1000research.163800.2","asserted-by":"subject"},{"id-type":"doi","id":"10.12688\/f1000research.163800.1","asserted-by":"subject"}]},"ISSN":["2046-1402"],"issn-type":[{"value":"2046-1402","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,4,28]]},"assertion":[{"value":"Indexed","URL":"https:\/\/f1000research.com\/articles\/14-472\/v3#article-reports","order":0,"name":"referee-status","label":"Referee status","group":{"name":"current-referee-status","label":"Current Referee Status"}},{"value":"10.5256\/f1000research.196367.r458400, Nelly Amenyogbe, Dalhousie University, Dalhousie, 03 Apr 2026, version 2, indexed","URL":"https:\/\/f1000research.com\/articles\/14-472\/v2#referee-response-458400","order":0,"name":"referee-response-458400","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"<b>Manoj Lalu<\/b>; \n<i>Posted: 08 Apr 2026<\/i>; We thank the reviewer for their feedback. Below please find our responses to their comments:  \n<b><u>Question 4. <\/u>Would suggest to change \u201c<i>Thus, the 8 hour model also mitigates survivorship bias as killing all animals at this timepoint will help ensure data collection from a full cohort.\u201d<\/i> -Instead of<i>&nbsp;\u201ckilling\u201d please use \u201ceuthanizing\u201d<\/i><\/b> \n<b>Response<\/b>: We thank the reviewer for this suggestion. However, following consultation with an animal welfare scientist, and in accordance with the CCAC Ethics Principles for Animal Use in Science (https:\/\/ccac.ca\/Documents\/Standards\/Guidelines\/CCAC_Ethics_Principles_for_Animal_Use_in_Science.pdf) , we have retained the term \u201chumane killing\u201d in the protocol to clearly distinguish between the two procedures (see Glossary, p. 25). We have revised the protocol to ensure consistent use of this terminology throughout. Euthanasia \u2212 Killing an animal when the reason for terminating the animal\u2019s life is for the benefit of the individual animal (this term is being phased out by the CCAC; humane killing will be used in all new and revised CCAC documents). Humane killing \u2212 The intentional ending of an animal\u2019s life using methods that demonstrate respect for the animal and minimize negative welfare impacts.  \n<b><u>Question 5.<\/u> \u201cMice will be specifically bred for this study by the Charles River facility in Saint-Constant, Quebec,<i>&nbsp;<\/i>Canada&nbsp;<i>(Charles River barrier facilities K61 and K92 (specific pathogen\u2013free). Animals will originate from breeding units (one male, two females) and wean according to standard procedures.\u201d<\/i> <i>-\u201cweaned\u201d instead of \u201cwean\u201d<\/i><\/b>   \n<b>Response<\/b>: Grammar is corrected now. \n<i>\u201c\u2026will be weaned\u2026\u201d<\/i>  \n<b>Minor methods details: <u>Question 7<\/u> (tail markings):&nbsp; Are these tail markings via permanent tattoo?&nbsp; Markers?&nbsp; If so what kind?&nbsp; For example there are specialized non-toxic markers made to identify mice (https:\/\/www.ketchum.ca\/product.htm?pid=963227).&nbsp; Would a product like this be utilized?<\/b>   \n<b>Response<\/b>: Yes, we used the non-toxic markers for the tail marking (Fine Science Tools Inc.). This info has now been added to the paper. \n<i>\u201c\u2026using tail markings (non-toxic markers (Fine Science Tools Inc.))\u2026\u201d<\/i>  \n<b><u>Question 8.<\/u>&nbsp; Please elaborate on the standardized injection volume by body weight \u2013 e.g. are you using 10 microliter per g BW (so 250 uL for a 25g mouse?) Given that the IP injection is also extra fluids given to the animal, having this detail in the protocol will help others implement these details.<\/b> \n<b>Response<\/b>: \n<u>We have added more details<\/u>\n<u> about the injection volume to the text.<\/u>\n<u> <\/u> \n<i>\u201cMice will receive approximately 15 uL of fecal slurry (50 mg\/mL) per gram of body weight. Across the expected weight range of 16-30 g, the difference in administered fecal slurry volume will be up to 200 &micro;L. As mice will be randomized across groups, this variation is expected to have minimal impact on experimental outcomes.\u201d<\/i>","URL":"https:\/\/f1000research.com\/articles\/14-472\/v3#referee-comment-15905","order":1,"name":"referee-comment-15905","label":"Referee Comment","group":{"name":"article-reports","label":"Article Reports"}},{"value":"10.5256\/f1000research.180201.r437806, Arnaud Mansart, Universit\u00e9 Paris-Saclay, Montigny le bretonneux, 31 Dec 2025, version 1, 1 approved, 1 approved with reservations","URL":"https:\/\/f1000research.com\/articles\/14-472\/v1#referee-response-437806","order":2,"name":"referee-response-437806","label":"Referee Report","group":{"name":"article-reports","label":"Article Reports"}},{"value":"<b>Manoj Lalu<\/b>; \n<i>Posted: 06 Feb 2026<\/i>; \n<b>Arnaud Mansart<\/b>,&nbsp;Universit&eacute; Paris-Saclay, Montigny le bretonneux, France&nbsp; \n<b>&nbsp;<\/b>\n<b>Approved<\/b> \n<b>info_outline<\/b> \n<b>1. Overall synthesis This study protocol describes a well-conceived and ambitious multicenter preclinical study that directly addresses several long-standing limitations in translational sepsis research. By adopting clinical-trial standards, the NPSP-01 study represents a meaningful methodological advance. Beyond its biological objectives, the study\u2019s main value lies in establishing a scalable and reproducible framework for future preclinical trials.<\/b>   \n<b>Major strengths A key strength of the protocol is its six-center randomized controlled design, which remains rare in animal research. This approach directly tackles issues of reproducibility and inter-laboratory variability, two major contributors to translational failure in sepsis. Modeling the study after multicenter clinical trials is therefore a notable and commendable advance. The methodological rigor is high. Centralized randomization stratified by center and sex, blinding at multiple stages, and clearly predefined primary and secondary outcomes all contribute to strong internal validity. The inclusion of clinically relevant standard-of-care interventions, particularly antibiotics and fluid resuscitation, substantially enhances construct and translational validity. Many experimental sepsis models omit these elements, limiting clinical relevance. Establishing a treated baseline is especially valuable for future evaluation of novel therapeutic strategies. The explicit inclusion of both male and female mice aligns well with current best practices and strengthens the biological relevance of the findings. Another major strength is the extensive feasibility and process evaluation. Metrics such as technical success rates, protocol adherence, and biobanking completion will generate highly informative data for the design of future multicenter preclinical studies, not only in sepsis but also in other disease areas. Finally, the authors strike a thoughtful balance between harmonization and real-world variability, avoiding excessive standardization. This reflects a sophisticated understanding of external validity and enhances the generalizability of the findings.<\/b>   We thank the reviewer for their careful review and insightful comments.&nbsp; We have addressed their concerns below and in the manuscript. We believe the edits made should address outstanding concerns.  \n<b>2. Areas for improvement and clarification The relatively short experimental time frame, with an 8-hour endpoint, limits insight into the dynamic kinetics of sepsis and the progression of organ dysfunction. While pragmatic, this constraint should be clearly acknowledged when interpreting results and extrapolating to human sepsis.<\/b> \n<b>Response: <\/b>We thank the reviewer for this insightful comment. We acknowledge that the 8h experimental timeframe limits assessment of sepsis progression and organ dysfunction over longer periods. We have added this to the limitation section in the discussion. \u201c\n<i>There are several aspects that should be considered when applying the model described in this protocol. 1) The 8h experimental timeframe limits assessment of longer-term sepsis progression and organ dysfunction, and modifications would be required for studies addressing these aspects\u2026<\/i>.\u201d \n<b>4. Important dimensions such as age-related dysfunction are not addressed. Although sex diversity is intentionally introduced, age (a major determinant of sepsis susceptibility, immune response, and outcome) is not considered.<\/b> \n<b>Response:<\/b> We agree, however as first step we want to ensure feasibility in a younger, healthier cohort prior to considering more resource intensive experiments in comorbid and aged animals. We plan to extend the model in future studies to incorporate additional complexity. This has now been addressed as a limitation in the discussion. \u201c\u2026\n<i>2) The use of young animals does not capture age-related physiological changes or disease susceptibility; future adaptations incorporating aged animals, neonatal models, or relevant comorbidities may improve construct validity\u2026\u201d<\/i>  \n<b>5. The protocol would also benefit from a clearer discussion of downstream decision rules. It is not specified what degree of inter-laboratory heterogeneity would be considered acceptable, or how such variability will inform future study design, sample size calculations, or protocol refinement.<\/b> \n<b>Response:<\/b> We agree that clearer downstream decision rules strengthen the protocol. There are no universally accepted thresholds defining \u201cacceptable\u201d versus \u201chigh\u201d inter-laboratory variability in multicentre clinical trials (i.e., where these issues have been studied extensively). Rather, interpretation is context-dependent and informed by empirical distributions of site-level variance. We have now clarified how inter-laboratory heterogeneity will be interpreted using intraclass correlation coefficients (ICCs), and how these estimates will inform protocol refinement, sample size assumptions, and design choices for future multilaboratory studies.  Statistical analysis plan: \u201cThe random effects analyses will be used to quantify variability in \n<i>the IL6<\/i> outcome between centers using intracluster correlation coefficients (ICCs). \n<i>Intracluster correlation coefficient estimates the proportion of total outcome variance attributable to between-laboratory differences. Consistent with practice in multicentre clinical trials, smaller ICC values will be interpreted as indicating limited between-laboratory heterogeneity, whereas larger values will prompt closer examination of protocol implementation and contextual sources of variability rather than being treated as a priori unacceptable<\/i>.\u201d Discussion: \u201c\n<i>Estimates of interlaboratory variance from NPSP-01 may help inform the design of subsequent multilaboratory studies by guiding assumptions for sample size calculations, determining whether center should be modeled as a random effect, and identifying domains where additional harmonization or training may be required. Where substantial heterogeneity is observed, future protocols will need to consider incorporating targeted refinements, or modified designs to improve interpretability<\/i>.\u201d  \n<b>6. Additional methodological considerations Several sources of variability occurring before and after the experimental protocol deserve further attention. The sanitary status of the animal facilities prior to study initiation is critical, as undetected infections or contaminations will significantly influence outcomes. Environmental factors such as room temperature are not monitored, despite their impact on hypothermia and long-term survival in septic mice. These aspects could be documented.<\/b> \n<b>Response:<\/b> We thank the reviewer for this comment. Procedures for temperature and humidity monitoring, as well as the cage change schedule, are defined in our protocols. This information has now been added to the manuscript: \u201c\n<i>Temperature and humidity will be documented within each animal facility. To maintain sanitary status, cage changes will be performed every 10-14 days, or earlier if cage soiling exceeds each centre\u2019s standard thresholds, in line with local animal care procedures<\/i>.\u201d  \n<b>7. Internal variability within individual laboratories is not explicitly assessed. This could be evaluated using simple, pragmatic parameters all of which can serve as indicators of technical reproducibility.<\/b>  \n<b>Response:<\/b> Intra-centre variability will be reported using 95% confidence intervals around the primary outcome (IL6) estimate. The approach was described in section \u201c\n<i>Inter-laboratory variability analysis\u201d <\/i>in the manuscript. \n<b>8. Finally, there is a potential procedural bias related to fluid administration. The sepsis group does not receive a dextrose\u2013glycerol injection at T4, unlike the other groups, which may induce unnecessary differences in long-term hypovolemia. Does the buprenorphine injection adequately compensate for this difference?<\/b> \n<b>Response:<\/b> None of the groups receive dextrose-glycerol at T4; only the treatment groups receive fluids and antibiotics, while the sepsis group does not. We acknowledge this as a potential limitation, but fluid resuscitation and antibiotics represent the primary intervention under study. Therefore, we could not compensate for administered volume in the sepsis group. \n<b>8. Conclusion Overall, this protocol represents a landmark step forward in preclinical sepsis research. Its greatest contribution may lie less in its biological findings and more in its rigorous, transparent, and reproducible trial-like framework. With additional analyses that explicitly account for, rather than avoid, sources of variability, the study has strong potential to shape the design of future multicenter preclinical investigations and improve translational success in sepsis research.<\/b> We again thank the reviewer for their positive comments and recognizing the value of our planned approach.","URL":"https:\/\/f1000research.com\/articles\/14-472\/v3#referee-comment-15422","order":3,"name":"referee-comment-15422","label":"Referee Comment","group":{"name":"article-reports","label":"Article Reports"}},{"value":"The National Preclinical Sepsis Platform is funded by Sepsis Canada (a network funded by the Canadian Institutes of Health Research) as well as an Exploration Grant from the New Frontiers in Research Fund. M.M.L. is supported by the Ottawa Hospital Anesthesia Alternate Funds Association, the Canadian Anesthesiologists\u2019 Society Career Investigator Award and holds a University of Ottawa Junior Research Chair in Innovative Translational Research. AAM is supported by the Manitoba Medical Services Foundation Dr. F. W. DuVal and John Henson Clinical Research Professorship. PCL holds the Jack Hirsh and Clive Kearon Endowed Chair in Thrombosis Research. AFR is the Scientific Director of Sepsis Canada and holds the Hamilton Health Sciences Chair in Sepsis Research. The funding agencies had no role in the design of the study, analysis, or writing of the manuscript. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.","order":4,"name":"grant-information","label":"Grant Information"},{"value":"This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.","order":0,"name":"copyright-info","label":"Copyright"}]}}