Patterns of invasive recurrence among patients originally treated for ductal carcinoma in situ by breast-conserving surgery versus mastectomy.

PURPOSE: Local recurrence after treatment of ductal carcinoma in situ (DCIS) with breast-conserving surgery (BCS) is more common than after mastectomy, but it is unclear if patterns of invasive recurrence vary by initial surgical therapy. Among patients with invasive recurrence after treatment for DCIS, we compared patterns of first recurrence between those originally treated with BCS vs. mastectomy. METHODS: From 2000 to 2016, women with an invasive recurrence occurring ≥ 6 months after initial treatment for DCIS were retrospectively identified. Clinicopathologic features and adjuvant treatment of the initial DCIS, as well as characteristics of first invasive recurrences, were compared between patients who had undergone BCS vs. mastectomy. RESULTS: 452 patients with an invasive recurrence after surgery for DCIS were identified: 367 patients (81%) had initially undergone BCS and 85 patients (19%) mastectomy. Patients originally treated with mastectomy were younger and were more likely to have had high grade, necrosis, and multifocal or multicentric DCIS (p < 0.001) compared with the BCS group. A higher proportion of invasive recurrences were local after BCS (93%; 343/367), whereas 88% (75/85) of recurrences after mastectomy were regional or distant (p < 0.001). The median time to first invasive recurrence was not different between surgical groups (BCS: 6.4 years vs. mastectomy: 5.5 years; p = 0.12). CONCLUSIONS: Among women who experienced a first invasive recurrence after treatment for DCIS, those who had originally undergone mastectomy more commonly presented with advanced disease compared to those treated with BCS, likely related to the absence of the breast and the higher risk profile of their initial DCIS.

Tumor Biology Predicts Pathologic Complete Response to Neoadjuvant Chemotherapy in Patients Presenting with Locally Advanced Breast Cancer.

BACKGROUND: Neoadjuvant chemotherapy (NAC) is used to convert patients with inoperable locally advanced breast cancer (LABC) to operability, but has not traditionally been used to avoid mastectomy or axillary dissection in this subset. OBJECTIVE: The purpose of this study was to determine the rates of pathologic complete response (pCR) in LABC patients, and identify factors predictive of pCR to determine if responding patients might be suitable for limited surgery. METHODS: From 2006 to 2016, 1522 patients received NAC followed by surgery; 321 had advanced disease in the breast (cT4) and/or in the nodes (cN2/N3). pCR rates were assessed by T and N stage, and receptor subtype. RESULTS: Of 321 LABC patients, 223 were cT4, 77 were cN2, and 82 were cN3. Forty-three percent were hormone receptor (HR) positive/human epidermal growth factor receptor 2 (HER2) negative (HR+/HER2-), 23% were triple negative, and 34% were HER2+. The overall pCR rate was 25% and differed by receptor subtype (HR+/HER2- 7%, triple negative 23%, HER2+ 48%; p < 0.001). Breast pCR occurred in 27% of patients and was similar in T4 versus non-T4 disease (29% vs. 22%; p = 0.26). Nodal pCR was achieved in 38% of cN+ patients and did not differ by nodal stage (cN1 43%, cN2 36%, cN3 32%; p = 0.23). Nodal pCR was significantly more common than breast pCR (p = 0.014) across all tumor subtypes. Receptor subtype was the only predictor of overall pCR (p < 0.001). CONCLUSION: In patients with LABC, pCR after NAC was seen in 25%, and did not differ by T or N stage. Tumor biology, but not extent of disease, predicted pCR. Studies assessing the feasibility of surgical downstaging with NAC in LABC patients are warranted.

Sepsis Pathophysiology, Chronic Critical Illness, and Persistent Inflammation-Immunosuppression and Catabolism Syndrome.

OBJECTIVES: To provide an appraisal of the evolving paradigms in the pathophysiology of sepsis and propose the evolution of a new phenotype of critically ill patients, its potential underlying mechanism, and its implications for the future of sepsis management and research. DESIGN: Literature search using PubMed, MEDLINE, EMBASE, and Google Scholar. MEASUREMENTS AND MAIN RESULTS: Sepsis remains one of the most debilitating and expensive illnesses, and its prevalence is not declining. What is changing is our definition(s), its clinical course, and how we manage the septic patient. Once thought to be predominantly a syndrome of over exuberant inflammation, sepsis is now recognized as a syndrome of aberrant host protective immunity. Earlier recognition and compliance with treatment bundles has fortunately led to a decline in multiple organ failure and in-hospital mortality. Unfortunately, more and more sepsis patients, especially the aged, are suffering chronic critical illness, rarely fully recover, and often experience an indolent death. Patients with chronic critical illness often exhibit "a persistent inflammation-immunosuppression and catabolism syndrome," and it is proposed here that this state of persisting inflammation, immunosuppression and catabolism contributes to many of these adverse clinical outcomes. The underlying cause of inflammation-immunosuppression and catabolism syndrome is currently unknown, but there is increasing evidence that altered myelopoiesis, reduced effector T-cell function, and expansion of immature myeloid-derived suppressor cells are all contributory. CONCLUSIONS: Although newer therapeutic interventions are targeting the inflammatory, the immunosuppressive, and the protein catabolic responses individually, successful treatment of the septic patient with chronic critical illness and persistent inflammation-immunosuppression and catabolism syndrome may require a more complementary approach.

A Case of a Giant Borderline Phyllodes Tumor Early in Pregnancy Treated with Mastectomy and Immediate Breast Reconstruction.

Breast tumors in pregnancy are often times diagnosed at advanced stages secondary to difficulty distinguishing between pathologic from normal physiologic changes. Often benign, phyllodes tumors are rare fibroepithelial stromal tumors of the breast, most commonly diagnosed in the 4th and 5th decades of life. However, these tumors may be characterized by malignancy with metastases in 10% of cases. In this paper, we report a novel case of a young woman presenting at 8 weeks gestation with a large borderline phyllodes tumor. An exceedingly rare condition, with only nine previously reported cases, phyllodes tumors in pregnancy frequently display more aggressive characteristics with larger median tumor size, more malignant potential, and more rapid growth rate. Here, we describe our experience safely and effectively treating this rare condition in a young gravid women with mastectomy and immediate breast reconstruction in the second trimester.

Calciphylaxis of the Breast: A Case Report and Literature Review.

Calciphylaxis, or calcific uremic arteriolopathy, is a rare but particularly morbid condition involving systemic medial calcification of arterioles causing ischemia and subsequent tissue necrosis. Although most commonly occurring over the abdomen and proximal extremities, calciphylaxis can present on nearly any skin surface with a tendency toward areas of increased adiposity. We report a case of a 53-year-old female with end-stage renal disease who presented with bilateral palpable breast masses and overlying skin changes. Diagnostic mammography and percutaneous biopsy of the lesion facilitated the diagnosis of calciphylaxis and she was treated with medical therapy, local wound care, and eventual tissue extirpation. Due to the morbidity attributed to calciphylaxis and associated wound complications, surgical extirpation is at times unavoidable. Once malignancy has been excluded, we recommend nonoperative management with prompt referral to Nephrology for medical optimization, reserving surgical debridement for nonhealing wounds and superinfection.

Ultrasound-Guided Segmental Mastectomy and Excisional Biopsy Using Hydrogel-Encapsulated Clip Localization as an Alternative to Wire Localization.

BACKGROUND: Wire localization is currently the most widely used localization strategy for excision of nonpalpable breast lesions. Its disadvantages include patient discomfort, wire-related complications such as wire displacement/fracture, and operating room delays related to difficulties during wire placement. We have implemented the technique of intraoperative ultrasound-guided excision using hydrogel-encapsulated (HydroMARK) biopsy clips for lesion localization. We hypothesize that this method is as effective as wire localization for breast conserving therapy. METHODS: This is a retrospective review of 220 consecutive patients who underwent segmental mastectomy or excisional biopsy using wire localization or hydrogel-encapsulated clip localization from January 2014 to July 2015. Data were collected and analyzed. Statistical analyses for differences between groups were performed using t tests and Mann-Whitney rank-sum analyses. RESULTS: A total of 107 excisions were performed using hydrogel-encapsulated clip localization, and 113 excisions were performed using the traditional wire localization technique; 68 % of our patients underwent excision for malignant pathology. Wire placement took a mean of 46 minutes (range 20-180 min), compared with 5 minutes for ultrasound localization (p <  .001). Successful intraoperative ultrasound localization and excision was performed on 100 % of patients. There was no difference in re-excision rates for positive margins or overall specimen size between the two groups. CONCLUSIONS: Intraoperative ultrasound-guided excision of nonpalpable breast lesions using a hydrogel-encapsulated biopsy clip for breast conserving therapy is a safe and feasible alternative to the traditional preoperative wire localized excision. This technique will lead to improvement in patient experience, operative efficiency, and alleviate wire-related complications.

Patterns of gene expression among murine models of hemorrhagic shock/trauma and sepsis.

Controversy remains whether the leukocyte genomic response to trauma or sepsis is dependent upon the initiating stimulus. Previous work illustrated poor correlations between historical models of murine trauma and sepsis (i.e., trauma-hemorrhage and lipopolysaccharide injection, respectively). The aim of this study is to examine the early genomic response in improved murine models of sepsis [cecal ligation and puncture (CLP)] and trauma [polytrauma (PT)] with and without pneumonia (PT+Pp). Groups of naïve, CLP, PT, and PT+Pp mice were killed at 2 h, 1 or 3 days. Total leukocytes were isolated for genome-wide expression analysis, and genes that were found to differ from control (false discovery rate adjusted P < 0.001) were assessed for fold-change differences. Spearman correlations were also performed. For all time points combined (CLP, PT, PT+Pp), there were 10,426 total genes that were found to significantly differ from naïve controls. At 2 h, the transcriptomic changes between CLP and PT showed a positive correlation (rs) of 0.446 (P < 0.0001) but were less positive thereafter. Correlations were significantly improved when we limited the analysis to common genes whose expression differed by a 1.5 fold-change. Both pathway and upstream analyses revealed the activation of genes known to be associated with pathogen-associated and damage-associated molecular pattern signaling, and early activation patterns of expression were very similar between polytrauma and sepsis at the earliest time points. This study demonstrates that the early leukocyte genomic response to sepsis and trauma are very similar in mice.

A Detailed Characterization of the Dysfunctional Immunity and Abnormal Myelopoiesis Induced by Severe Shock and Trauma in the Aged.

The elderly are particularly susceptible to trauma, and their outcomes are frequently dismal. Such patients often have complicated clinical courses and ultimately die of infection and sepsis. Recent research has revealed that although elderly subjects have increased baseline inflammation as compared with their younger counterparts, the elderly do not respond to severe infection or injury with an exaggerated inflammatory response. Initial retrospective analysis of clinical data from the Glue Grant trauma database demonstrated that despite a similar frequency, elderly trauma patients have worse outcomes to pneumonia than younger subjects do. Subsequent analysis with a murine trauma model also demonstrated that elderly mice had increased mortality after posttrauma Pseudomonas pneumonia. Blood, bone marrow, and bronchoalveolar lavage sample analyses from juvenile and 20-24-mo-old mice showed that increased mortality to trauma combined with secondary infection in the aged are not due to an exaggerated inflammatory response. Rather, they are due to a failure of bone marrow progenitors, blood neutrophils, and bronchoalveolar lavage cells to initiate and complete an emergency myelopoietic response, engendering myeloid cells that fail to clear secondary infection. In addition, elderly people appeared unable to resolve their inflammatory response to severe injury effectively.

Clostridium difficile Infections after Blunt Trauma: A Different Patient Population?

BACKGROUND: The epidemiology of Clostridium difficile-associated infection (CDI) has changed, and it is evident that susceptibility is related not only to exposures and bacterial potency, but host factors as well. Several small studies have suggested that CDI after trauma is associated with a different patient phenotype. The purpose of this study was to examine and describe the epidemiologic factors associated with C. difficile in blunt trauma patients without traumatic brain injury using the Trauma-Related Database as a part of the "Inflammation and Host Response to Injury" (Glue Grant) and the University of Florida Integrated Data Repository. METHODS: Previously recorded baseline characteristics, clinical data, and outcomes were compared between groups (67 C. difficile and 384 uncomplicated, 813 intermediate, and 761 complicated non-C. difficile patients) as defined by the Glue Grant on admission and at days seven and 14. RESULTS: The majority of CDI patients experienced complicated or intermediate clinical courses. The mean ages of all cohorts were less than 65 y and CDI patients were significantly older than uncomplicated patients without CDI. The CDI patients had increased days in the hospital and on the ventilator, as well as significantly higher new injury severity scores (NISS), and a greater percentage of patients with NISS >34 points compared with non-CDI patients. They also had greater Marshall and Denver multiple organ dysfunction scores than non-CDI uncomplicated patients, and greater creatinine, alkaline phosphatase, neutrophil count, lactic acid, and PiO2:FiO2 compared with all non-CDI cohorts on admission. In addition, the CDI patients had higher glucose concentrations and base deficit from uncomplicated patients and greater leukocytosis than complicated patients on admission. Several of these changes persisted to days seven and 14. CONCLUSION: Analysis of severe blunt trauma patients with C. difficile, as compared with non-CDI patients, reveals evidence of increased inflammation, immunosuppression, worse acute kidney injury, higher NISS, greater days in the hospital and on the ventilator, higher organ injury scores, and prolonged clinical courses. This supports reports of an increased prevalence of CDI in a younger population not believed previously to be at risk. This unique population may have specific genomic or inflammation-related risk factors that may play more important roles in disease susceptibility. Prospective analysis may allow early identification of at-risk patients, creation of novel therapeutics, and improved understanding of how and why C. difficile colonization transforms into infection after severe blunt trauma.

Successful implementation of a packed red blood cell and fresh frozen plasma transfusion protocol in the surgical intensive care unit.

BACKGROUND: Blood product transfusions are associated with increased morbidity and mortality. The purpose of this study was to determine if implementation of a restrictive protocol for packed red blood cell (PRBC) and fresh frozen plasma (FFP) transfusion safely reduces blood product utilization and costs in a surgical intensive care unit (SICU). STUDY DESIGN: We performed a retrospective, historical control analysis comparing before (PRE) and after (POST) implementation of a restrictive PRBC/FFP transfusion protocol for SICU patients. Univariate analysis was utilized to compare patient demographics and blood product transfusion totals between the PRE and POST cohorts. Multivariate logistic regression models were developed to determine if implementation of the restrictive transfusion protocol is an independent predictor of adverse outcomes after controlling for age, illness severity, and total blood products received. RESULTS: 829 total patients were included in the analysis (PRE, n=372; POST, n=457). Despite higher mean age (56 vs. 52 years, p=0.01) and APACHE II scores (12.5 vs. 11.2, p=0.006), mean units transfused per patient were lower for both packed red blood cells (0.7 vs. 1.2, p=0.03) and fresh frozen plasma (0.3 vs. 1.2, p=0.007) in the POST compared to the PRE cohort, respectively. There was no difference in inpatient mortality between the PRE and POST cohorts (7.5% vs. 9.2%, p=0.39). There was a decreased risk of urinary tract infections (OR 0.47, 95%CI 0.28-0.80) in the POST cohort after controlling for age, illness severity and amount of blood products transfused. CONCLUSIONS: Implementation of a restrictive transfusion protocol can effectively reduce blood product utilization in critically ill surgical patients with no increase in morbidity or mortality.

Advanced age is associated with worsened outcomes and a unique genomic response in severely injured patients with hemorrhagic shock.

INTRODUCTION: We wished to characterize the relationship of advanced age to clinical outcomes and to transcriptomic responses after severe blunt traumatic injury with hemorrhagic shock. METHODS: We performed epidemiological, cytokine, and transcriptomic analyses on a prospective, multi-center cohort of 1,928 severely injured patients. RESULTS: We found that there was no difference in injury severity between the aged (age ≥55, n = 533) and young (age <55, n = 1395) cohorts. However, aged patients had more comorbidities. Advanced age was associated with more severe organ failure, infectious complications, ventilator days, and intensive care unit length of stay, as well as, an increased likelihood of being discharged to skilled nursing or long-term care facilities. Additionally, advanced age was an independent predictor of a complicated recovery and 28-day mortality. Acutely after trauma, blood neutrophil genome-wide expression analysis revealed an attenuated transcriptomic response as compared to the young; this attenuated response was supported by the patients' plasma cytokine and chemokine concentrations. Later, these patients demonstrated gene expression changes consistent with simultaneous, persistent pro-inflammatory and immunosuppressive states. CONCLUSIONS: We concluded that advanced age is one of the strongest non-injury related risk factors for poor outcomes after severe trauma with hemorrhagic shock and is associated with an altered and unique peripheral leukocyte genomic response. As the general population's age increases, it will be important to individualize prediction models and therapeutic targets to this high risk cohort.

Improved emergency myelopoiesis and survival in neonatal sepsis by caspase-1/11 ablation.

Over one million newborns die annually from sepsis with the highest mortality in premature and low-birthweight infants. The inflammasome plays a central role in the regulation of innate immunity and inflammation, and is presumed to be involved in protective immunity, in large part through the caspase-1-dependent activation of interleukin-1ß (IL-1ß) and IL-18. Studies in endotoxic shock, however, suggest that endogenous caspase-1 activity and the inflammasome contribute to mortality primarily by promoting excessive systemic inflammatory responses. We examined whether caspase-1 and the inflammasome also regulate neonatal inflammation, host protective immunity and myelopoiesis during polymicrobial sepsis. Neonatal (5-7 days) C57BL/6 and caspase-1/11(-/-) mice underwent a low-lethality caecal slurry model of intra-abdominal sepsis (LD25-45 ). Ablation of caspase-1/11, but not apoptosis-associated speck-like protein containing a CARD domain or nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), improved neonatal survival following septic challenge compared with wild-type mice (P < 0·001), with decreased concentrations of inflammatory cytokines in the serum and peritoneum. Surprisingly, caspase-1/11(-/-) neonates also exhibited increased bone marrow and splenic haematopoietic stem cell expansion (P < 0·001), and increased concentrations of granulocyte and macrophage colony-stimulating factors in the peritoneum (P < 0·001) after sepsis. Ablation of caspase-1/11 signalling was also associated with increased recruitment of peritoneal macrophages and neutrophils (P < 0·001), increased phagocytosis by neutrophils (P = 0·003), and decreased bacterial colonization (P = 0·02) in the peritoneum. These findings suggest that endogenous caspase-1/11 activity, independent of the NLRP3 inflammasome, not only promotes the magnitude of the inflammatory response, but also suppresses protective immunity in the neonate, so contributing to innate immune dysfunction and poor survival in neonatal sepsis.

TRIF-dependent innate immune activation is critical for survival to neonatal gram-negative sepsis.

Current evidence suggests that neonatal immunity is functionally distinct from adults. Although TLR signaling through the adaptor protein, MyD88, has been shown to be critical for survival to sepsis in adults, little is known about the role of MyD88 or TRIF in neonatal sepsis. We demonstrate that TRIF(-/-) but not MyD88(-/-) neonates are highly susceptible to Escherichia coli peritonitis and bacteremia. This was associated with decreased innate immune recruitment and function. Importantly, we found that the reverse was true in adults that MyD88(-/-) but not TRIF(-/-) or wild-type adults are susceptible to E. coli peritonitis and bacteremia. In addition, we demonstrate that TRIF but not MyD88 signaling is critical for the TLR4 protective adjuvant effect we have previously demonstrated. These data suggest a differential requirement for the survival of neonates versus adults to Gram-negative infection, and that modulation of TRIF in neonates can be used to augment survival to neonatal sepsis.

Delayed emergency myelopoiesis following polymicrobial sepsis in neonates.

Neonates have increased susceptibility to infection, which leads to increased mortality. Whether or not this as a result of implicit deficits in neonatal innate immune function or recapitulation of innate immune effector cell populations following infection is unknown. Here, we examine the process of emergency myelopoiesis whereby the host repopulates peripheral myeloid cells lost following the initial infectious insult. As early inflammatory responses are often dependent upon NF-κB and type I IFN signaling, we also examined whether the absence of MyD88, TRIF or MyD88 and TRIF signaling altered the myelopoietic response in neonates to polymicrobial sepsis. Following neonatal polymicrobial septic challenge, hematopoietic stem cell (HSC) expansion in bone marrow and the spleen were both attenuated and delayed in neonates compared with adults. Similar reductions in other precursors were observed in neonates. Similar to adult studies, the expansion of progenitor stem cell populations was also seen in the absence of MyD88 and/or TRIF signaling. Overall, neonates have impaired emergency myelopoiesis in response to sepsis compared with young adults. Despite reports that this expansion may be related to TLR signaling, our data suggest that other factors may be important, as TRIF(-/-) and MyD88(-/-) neonatal HSCs are still able to expand in response to polymicrobial neonatal sepsis.

Novel role for tumor-induced expansion of myeloid-derived cells in cancer cachexia.

Cancer progression is associated with inflammation, increased metabolic demand, infection, cachexia, and eventually death. Myeloid-derived suppressor cells (MDSCs) commonly expand during cancer and are associated with adaptive immune suppression and inflammatory metabolite production. We propose that cancer-induced cachexia is driven at least in part by the expansion of MDSCs. MDSC expansion in 4T1 mammary carcinoma-bearing hosts is associated with induction of a hepatic acute-phase protein response and altered host energy and fat metabolism, and eventually reduced survival to polymicrobial sepsis and endotoxemia. Similar results are also seen in mice bearing a Lewis lung carcinoma and a C26 colon adenocarcinoma. However, a similar cachexia response is not seen with equivalent growth of the 66C4 subclone of 4T1, in which MDSC expansion does not occur. Importantly, reducing MDSC numbers in 4T1-bearing animals can ameliorate some of these late responses and reduce susceptibility to inflammation-induced organ injury and death. In addition, administering MDSCs from both tumor- and nontumor-bearing mice can produce an acute-phase response. Thus, we propose a previously undescribed mechanism for the development of cancer cachexia, whereby progressive MDSC expansion contributes to changes in host protein and energy metabolism and reduced resistance to infection.

Host responses to sepsis vary in different low-lethality murine models.

INTRODUCTION: Animal models for the study of sepsis are being increasingly scrutinized, despite their essential role for early translational research. In particular, recent studies have suggested that at the level of the leukocyte transcriptome, murine models of burns, trauma and endotoxemia markedly differ from their human equivalents, and are only weakly similar amongst themselves. We compared the plasma cytokine and leukocyte transcriptome responses between two different low-lethality murine models of polymicrobial intra-abdominal sepsis. METHODS: Six to ten week male C57BL/6j mice underwent either the 'gold standard' cecal ligation and puncture (CLP) model of intra-abdominal sepsis or administration of a cecal slurry (CS), where cecal contents are injected intraperitoneally. Surviving mice were euthanized at two hours, one or three days after sepsis. RESULTS: The murine leukocyte transcriptomic response to the CLP and CS models of sepsis was surprisingly dissimilar at two hours, one, and three days after sepsis. The Pearson correlation coefficient for the maximum change in expression for the entire leukocyte transcriptome that changed significantly over time (n = 19,071) was R = 0.54 (R2 = 0.297). The CS model resulted in greater magnitude of early inflammatory gene expression changes in response to sepsis with associated increased production of inflammatory chemokines and cytokines. Two hours after sepsis, CLP had more significant expression of genes associated with IL-10 signaling pathways, whereas CS had greater expression of genes related to CD28, apoptosis, IL-1 and T-cell receptor signaling. By three days, the changes in gene expression in both sepsis models were returning to baseline in surviving animals. CONCLUSION: These analyses reveal that the murine blood leukocyte response to sepsis is highly dependent on which model of intra-abdominal sepsis is employed, despite their similar lethality. It may be difficult to extrapolate findings from one murine model to another, let alone to human sepsis.

Protective immunity and defects in the neonatal and elderly immune response to sepsis.

Populations encompassing extremes of age, including neonates and elderly, have greater mortality from sepsis. We propose that the increased mortality observed in the neonatal and elderly populations after sepsis is due to fundamental differences in host-protective immunity and is manifested at the level of the leukocyte transcriptome. Neonatal (5-7 d), young adult (6-12 wk), or elderly (20-24 mo) mice underwent a cecal slurry model of intra-abdominal sepsis. Both neonatal and elderly mice exhibited significantly greater mortality to sepsis (p < 0.05). Neonates in particular exhibited significant attenuation of their inflammatory response (p < 0.05), as well as reductions in cell recruitment and reactive oxygen species production (both p < 0.05), all of which could be confirmed at the level of the leukocyte transcriptome. In contrast, elderly mice were also more susceptible to abdominal peritonitis, but this was associated with no significant differences in the magnitude of the inflammatory response, reduced bacterial killing (p < 0.05), reduced early myeloid cell activation (p < 0.05), and a persistent inflammatory response that failed to resolve. Interestingly, elderly mice expressed a persistent inflammatory and immunosuppressive response at the level of the leukocyte transcriptome, with failure to return to baseline by 3 d. This study reveals that neonatal and elderly mice have profoundly different responses to sepsis that are manifested at the level of their circulating leukocyte transcriptome, although the net result of increased mortality is similar. Considering these differences are fundamental aspects of the genomic response to sepsis, interventional therapies will require individualization based on the age of the population.

HMGB1 as a therapeutic target for sepsis: it's all in the timing!

Morbidity and mortality from severe sepsis remain high, despite decades of research and improvements in intensive care unit (ICU) care. There have been over 100 failed clinical trials of biological response modifiers aimed at single therapeutic targets, mostly to suppress the early pro-inflammatory responses. In the last decade, extracellular HMGB1 has emerged as a late mediator of sepsis in murine sepsis models, whose blockade improves mortality and has a wider therapeutic window than previous efforts. Although this review promulgates the use of HMGB1 inhibitor as a therapeutic target, it should be recognized that it may not be an optimal approach to the early systemic inflammatory response syndrome (SIRS) response and cytokine storm, but rather for those patients who survive their cytokine storm and present with a persistent inflammatory, immunosuppressive and catabolism response (PICS). With earlier implementation of evidence-based best care principles for treating sepsis, fewer patients are dying from early septic shock, and there is an endemic increase in sepsis survivors with dismal long-term outcomes. These patients have ongoing inflammatory processes that may well be driven by the late and continued release of HMGB1 and other damage-associated molecular patterns receptors (DAMPRs). HMGB1 therapeutics, whether antibodies or natural herbal approaches, may be one novel approach for targeting not the early, but the late persistent inflammation of sepsis survivors.

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.