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Dina C Nacionales

Publications and source records attributed to Dina C Nacionales.

2 recordsLinked to original sources

A better understanding of why murine models of trauma do not recapitulate the human syndrome.

OBJECTIVE: Genomic analyses from blood leukocytes have concluded that mouse injury poorly reflects human trauma at the leukocyte transcriptome. Concerns have focused on the modest severity of murine injury models, differences in murine compared with human age, dissimilar circulating leukocyte populations between species, and whether similar signaling pathways are involved. We sought to examine whether the transcriptomic response to severe trauma in mice could be explained by these extrinsic factors, by utilizing an increasing severity of murine trauma and shock in young and aged mice over time, and by examining the response in isolated neutrophil populations. DESIGN: Preclinical controlled in vivo laboratory study and retrospective cohort study. SETTING: Laboratory of Inflammation Biology and Surgical Science and multi-institution level 1 trauma centers. SUBJECTS: Six- to 10-week-old and 20- to 24-month-old C57BL/6 (B6) mice and two cohorts of 167 and 244 severely traumatized (Injury Severity Score > 15) adult (> 18 yr) patients. INTERVENTIONS: Mice underwent one of two severity polytrauma models of injury. Total blood leukocyte and neutrophil samples were collected. MEASUREMENTS AND MAIN RESULTS: Fold expression changes in leukocyte and neutrophil genome-wide expression analyses between healthy and injured mice (p < 0.001) were compared with human total and enriched blood leukocyte expression analyses of severe trauma patients at 0.5, 1, 4, 7, 14, and 28 days after injury (Glue Grant trauma-related database). We found that increasing the severity of the murine trauma model only modestly improved the correlation in the transcriptomic response with humans, whereas the age of the mice did not. In addition, the genome-wide response to blood neutrophils (rather than total WBC) was also not well correlated between humans and mice. However, the expression of many individual gene families was much more strongly correlated after injury in mice and humans. CONCLUSIONS: Although overall transcriptomic association remained weak even after adjusting for the severity of injury, age of the animals, timing, and individual leukocyte populations, there were individual signaling pathways and ontogenies that were strongly correlated between mice and humans. These genes are involved in early inflammation and innate/adaptive immunity.

Adult

Persistent inflammation, immunosuppression, and catabolism syndrome after severe blunt trauma.

BACKGROUND: We recently proffered that a new syndrome persistent inflammation, immunosuppression, and catabolism syndrome (PICS) has replaced late multiple-organ failure as a predominant phenotype of chronic critical illness. Our goal was to validate this by determining whether severely injured trauma patients with complicated outcomes have evidence of PICS at the genomic level. METHODS: We performed a secondary analysis of the Inflammation and Host Response to Injury database of adults with severe blunt trauma. Patients were classified into complicated, intermediate, and uncomplicated clinical trajectories. Existing genomic microarray data were compared between cohorts using Ingenuity Pathways Analysis. Epidemiologic data and outcomes were also analyzed between cohorts on admission, Day 7, and Day 14. RESULTS: Complicated patients were older, were sicker, and required increased ventilator days compared with the intermediate/uncomplicated patients. They also had persistent leukocytosis as well as low lymphocyte and albumin levels compared with uncomplicated patients. Total white blood cell leukocyte analysis in complicated patients showed that overall genome-wide expression patterns and those patterns on Days 7 and 14 were more aberrant from control subjects than were patterns from uncomplicated patients. Complicated patients also had significant down-regulation of adaptive immunity and up-regulation of inflammatory genes on Days 7 and 14 (vs. magnitude in fold change compared with control and in magnitude compared with uncomplicated patients). On Day 7, complicated patients had significant changes in functional pathways involved in the suppression of myeloid cell differentiation, increased inflammation, decreased chemotaxis, and defective innate immunity compared with uncomplicated patients and controls. Subset analysis of monocyte, neutrophil, and T-cells supported these findings. CONCLUSION: Genomic analysis of patients with complicated clinical outcomes exhibit persistent genomic expression changes consistent with defects in the adaptive immune response and increased inflammation. Clinical data showed persistent inflammation, immunosuppression, and protein depletion. Overall, the data support the hypothesis that patients with complicated clinical outcomes are exhibiting PICS. LEVEL OF EVIDENCE: Epidemiologic study, level III.

Adolescent