Immunotherapy of Sepsis: Blind Alley or Call for Personalized Assessment?

Adjunctive immunotherapeutic agents in patients with sepsis and septic shock: a multidisciplinary consensus of 23

BACKGROUND

In the last decades, several adjunctive treatments have been proposed to reduce mortality in septic shock patients. Unfortunately, mortality due to sepsis and septic shock remains elevated and NO trials evaluating adjunctive therapies were able to demonstrate any clear benefit. In light of the lack of evidence and conflicting results from previous studies, in this multidisciplinary consensus, the authors considered the rational, recent investigations and potential clinical benefits of targeted adjunctive therapies.

METHODS

A panel of multidisciplinary experts defined clinical phenotypes, treatments and outcomes of greater interest in the field of adjunctive therapies for sepsis and septic shock. After an extensive systematic literature review, the appropriateness of each treatment for each clinical phenotype was determined using the modified RAND/UCLA appropriateness method.

RESULTS

The consensus identified two distinct clinical phenotypes: patients with overwhelming shock and patients with immune paralysis. Six different adjunctive treatments were considered the most frequently used and promising: (i) corticosteroids, (ii) blood purification, (iii) immunoglobulins, (iv) granulocyte/monocyte colony-stimulating factor and (v) specific immune therapy (i.e. interferon-gamma, IL7 and AntiPD1). Agreement was achieved in 70% of the 25 clinical questions.

CONCLUSIONS

Although clinical evidence is lacking, adjunctive therapies are often employed in the treatment of sepsis. To address this gap in knowledge, a panel of national experts has provided a structured consensus on the appropriate use of these treatments in clinical practice.

Non-conventional immunomodulation in the management of sepsis

Sepsis remains a critical global health issue, demanding novel therapeutic strategies. Traditional immunomodulation treatments such as corticosteroids, specific modifiers of cytokines, complement or coagulation, growth factors or immunoglobulins, have so far fallen short. Meanwhile the number of studies investigating non-conventional immunomodulatory strategies is expanding. This review provides an overview of adjunctive treatments with herbal-based medicine, immunonutrition, vasopressors, sedative treatments and targeted temperature management, used to modulate the immune response in patients with sepsis. Herbal-based medicine, notably within traditional Chinese medicine, shows promise. Xuebijing injection and Shenfu injection exhibit anti-inflammatory and immune-modulatory effects, and the potential to lower 28-day mortality in sepsis. Selenium supplementation has been reported to reduce the occurrence of ventilator-associated pneumonia among sepsis patients, but study results are conflicting. Likewise, the immune-suppressive effects of omega-3 fatty acids have been associated with improved clinical outcomes in sepsis. The immunomodulating properties of supportive treatments also gain interest. Vasopressors like norepinephrine exhibit dual dosage-dependent roles, potentially promoting both pro- and anti-inflammatory effects. Dexmedetomidine, a sedative, demonstrates anti-inflammatory properties, reducing sepsis mortality rates in some studies. Temperature management, particularly maintaining higher body temperature, has also been associated with improved outcomes in small scale human trials. In conclusion, emerging non-conventional immunomodulatory approaches, including herbal medicine, immunonutrition, and targeted supportive therapies, hold potential for sepsis treatment, but their possible implementation into everyday clinical practice necessitates further research and stringent clinical validation in different settings.

The tissue factor expression on CD14++CD16-monocytes is a new markers in the Chinese Han older adult population with sepsis: A prospective study

OBJECTIVE

To investigate the tissue factor (TF) expression on different subsets of monocyte and tissue factor secretion of peripheral blood and evaluate their association with the prognosis of sepsis in the Chinese older adult population.

METHODS

Monocyte subsets and TF expression on different subsets of monocyte were measured using flow cytometry in 80 older adult sepsis patients and 40 age and sex matched healthy controls. Plasma level of TF was measured using ELISA (enzyme-linked immunosorbent assay) method.

RESULTS

TF expression on CD14++CD16- (MO1) monocyte was lower in death (28-day non-survivor) group compared with survival (28-day survivor) groups [1.01 % (0.58 %, 1.62 %) vs. 3.66 % (1.32 %, 6.93 %), p = 0.001]. The plasma level of TF was increased in death group compared to survival group according to the 28-day mortality [109.2 (67.3, 154.2) vs. 62.1 (44.7, 115.5) pg/mL, p = 0.031]. Logistic regression analysis showed TF expression on MO1 monocyte (β = -0.776, OR = 0.460, CI: 0.251, 0.843, p = 0.012) was independently associated with the 28-day mortality. The ROC (receiver operating characteristic) curve showed that the AUC (area under the curve) of the TF expression on MO1 monocyte for predicting 28-day mortality was 0.846 (p < 0.001).

CONCLUSION

The TF expression on CD14++CD16- monocyte is a new marker for the prognosis of older adult sepsis.

Ethical Aspects of Personalized Research and Management of Systemic Inflammatory Response Syndrome (SIRS) in Children

Systemic inflammatory response syndrome (SIRS) is a life-threatening condition with nonspecific symptoms. Because of that, defining a targeted therapy against SIRS in children and adults remains a challenge. The identification of diagnostic patterns from individualized immuneprofiling can lead to development of a personalized therapy. The aim of this study was to identify and analyze ethical issues associated with personalized research and therapy for SIRS in pediatric populations. We conducted an ethical analysis based on a principled approach according to Beauchamp and Childress' four bioethical principles. Relevant information for the research objectives was extracted from a systematic literature review conducted in the scientific databases PubMed, Embase and Web of Science. We searched for pertinent themes dealing with at least one of the four bioethical principles: "autonomy", "non-maleficence", "beneficence" and "justice". 48 publications that met the research objectives were included in the thorough analysis, structured and discussed in a narrative synthesis. From the analysis of the results, it has emerged that traditional paradigms of patient's autonomy and physician paternalism need to be reexamined in pediatric research. Standard information procedures and models of informed consent should be reconsidered as they do not accommodate the complexities of pediatric omics research.

Inflammatory Monocytes and Subsets of Macrophages with Distinct Surface Phenotype Correlate with Specific Integrin Expression Profile during Murine Sepsis

Monocytes and macrophages participate in both pro- and anti-inflammatory responses during sepsis. Integrins are the cell adhesion receptors that mediate leukocyte migration and functions. To date, it is not known whether integrin profiles correlate with their trafficking, differentiation, and polarization during sepsis. In this study, using endotoxemia and cecal ligation and puncture model of murine sepsis, we have analyzed the role of surface integrins in tissue-specific infiltration, distribution of monocytes and macrophages, and their association with inflammation-induced phenotypic and functional alterations postinduction (p.i.) of sepsis. Our data show that Ly-6C^hi inflammatory monocytes infiltrated into the peritoneum from blood and bone marrow within a few hours p.i. of sepsis, with differential distribution of small (Ly-6C^loCD11b^loF4/80^lo) and large peritoneal macrophages (Ly-6C^loCD11b^hiF4/80^hi) in both models. The results from flow cytometry studies demonstrated a higher expression of integrin α₄β₁ on the Ly-6C^hi monocytes in different tissues, whereas macrophages in the peritoneum and lungs expressed higher levels of integrin α₅β₁ and α_vβ₃ in both models. Additionally, F4/80⁺ cells with CD206^hiMHCII^lo phenotype increased in the lungs of both models by six hours p.i. and expressed higher levels of integrin α_vβ₃ in both lungs and peritoneum. The presence of such cells correlated with higher levels of IL-10 and lower levels of IL-6 and IL-1β transcripts within six hours p.i. in the lungs compared with the mesentery. Furthermore, bioinformatic analysis with its experimental validation revealed an association of integrin α₄ and α₅ with inflammatory (e.g., p-SRC) and integrin α_v with regulatory molecules (e.g., TGFBR1) in macrophages during sepsis.

Cellular Markers of Immunosuppression in Sepsis

Sepsis is a pathological condition frequently caused by invasion of a pathogen and the subsequent unregulated response that threatens the patient's life through diverse organ failure. The incidence of sepsis is increasing, and there is no specific therapy. Despite technological contributions to treat sepsis or increased knowledge of its molecular pathophysiology, mortality remains high, and sepsis is a global health problem. Knowledge of the role of the cells involved in the host response through the synthesis of inflammatory mediators and their different effects on cells, tissues or systems is key to the development of medical treatments that regulate systems involved in such responses to pathogens. This review addresses new insights into the role of cells, their mediators, and the interaction between them that lead to the development of a state of immunosuppression.

The Critical Roles and Mechanisms of Immune Cell Death in Sepsis

Sepsis was first described by the ancient Greek physicians over 2000 years ago. The pathophysiology of the disease, however, is still not fully understood and hence the mortality rate is still unacceptably high due to lack of specific therapies. In the last decade, great progress has been made by shifting the focus of research from systemic inflammatory response syndrome (SIRS) to multiple organ dysfunction syndrome (MODS). Sepsis has been re-defined as infection-induced MODS in 2016. How infection leads to MODS is not clear, but what mediates MODS becomes the major topic in understanding the molecular mechanisms and developing specific therapies. Recently, the mechanism of infection-induced extensive immune cell death which releases a large quantity of damage-associated molecular patterns (DAMPs) and their roles in the development of MODS as well as immunosuppression during sepsis have attracted much attention. Growing evidence supports the hypothesis that DAMPs, including high-mobility group box 1 protein (HMGB1), cell-free DNA (cfDNA) and histones as well as neutrophil extracellular traps (NETs), may directly or indirectly contribute significantly to the development of MODS. Here, we provide an overview of the mechanisms and consequences of infection-induced extensive immune cell death during the development of sepsis. We also propose a pivotal pathway from a local infection to eventual sepsis and a potential combined therapeutic strategy for targeting sepsis.

Artesunate interacts with the vitamin D receptor to reverse sepsis-induced immunosuppression in a mouse model via enhancing autophagy

BACKGROUND AND PURPOSE

Immunosuppression is the predominant cause of mortality for sepsis because of failure to eradicate pathogens. No effective and specific drugs capable of reversing immunosuppression are clinically available. Evidences implicate the involvement of the vitamin D receptor (NR1I1) in sepsis-induced immunosuppression. The anti-malarial artesunate was investigated to determine action on sepsis-induced immunosuppression.

EXPERIMENTAL APPROACH

The effect of artesunate on sepsis-induced immunosuppression was investigated in mice and human and mice cell lines. Bioinformatics predicted vitamin D receptor as a candidate target for artesunate, which was then identified using PCR and immunoblotting. Vdr, Atg16l1 and NF-κB p65 were modified to investigate artesunate 's effect on pro-inflammatory cytokines release, bacterial clearance and autophagy activities in sepsis-induced immunosuppression.

KEY RESULTS

Artesunate significantly reduced the mortality of caecal ligation and puncture (CLP)-induced sepsis immunosuppression mice challenged with Pseudomonas aeruginosa and enhanced pro-inflammatory cytokine release and bacterial clearance to reverse sepsis-induced immunosuppression in vivo and in vitro. Mechanistically, artesunate interacted with vitamin D receptor, inhibiting its nuclear translocation, which influenced ATG16L1 transcription and subsequent autophagy activity. Artesunate inhibited the physical interaction between vitamin D receptor and NF-κB p65 in LPS-tolerant macrophages and then promoted the nuclear translocation of NF-κB p65, which activated the transcription of NF-κB p65 target genes such as pro-inflammatory cytokines.

CONCLUSION AND IMPLICATIONS

Our findings provide evidence that artesunate interacted with vitamin D receptor to reverse sepsis-induced immunosuppression in an autophagy and NF-κB-dependent manner, highlighting a novel approach for sepsis treatment and drug repurposing of artesunate has a bidirectional immunomodulator.

Tofacitinib treatment aggravates Staphylococcus aureus septic arthritis, but attenuates sepsis and enterotoxin induced shock in mice

Tofacitinib, a janus kinase inhibitor, is a novel immunosuppressive drug for treatment of rheumatoid arthritis (RA). Septic arthritis (SA) and sepsis caused by Staphylococcus aureus (S. aureus), for which RA patients are at risk, are infections with high mortality. The aim of this study was to investigate the effect of tofacitinib on S. aureus infections using mouse models. In vitro tofacitinib treated mouse splenocytes were stimulated with S. aureus derived stimuli. Mice pre-treated with tofacitinib were inoculated intravenously with either arthritogenic- or septic doses of S. aureus. Arthritis severity and mortality were compared between groups. Additionally, pre-treated mice were challenged with staphylococcal toxin TSST-1 to induce shock. Tofacitinib inhibited splenocyte proliferation and IFN-γ production in response to TSST-1 and dead S. aureus. In SA, tofacitinib treatment aggravated arthritis with more severe bone erosions. However, in sepsis, treated mice displayed significantly prolonged survival compared to controls. Similarly, in staphylococcal enterotoxin-induced shock tofacitinib pre-treatment, but not late treatment dramatically reduced mortality, which was accompanied by decreased levels of TNF-α and IFN-γ. Our findings show that tofacitinib treatment increase susceptibility of SA in mice, but has a positive effect on survival in S. aureus-induced sepsis and a strong protective effect in toxin-induced shock.

Detection of Early Cytokine Storm in Patients with Septic Shock After Abdominal Surgery

Objectives: To explore the characteristics of cytokine storm in patients with septic shock after abdominal surgery, examine its relationship with clinical data, and determine intervention timings.

Materials and Methods: We prospectively observed a cohort of patients with abdominal infection admitted to the surgical intensive care unit (ICU) after surgery (shock group). A control group of healthy individuals was used for comparison. Plasma samples and clinical data recorded at 0, 12, 24, 48, and 72 h after surgery were collected. Cytokines (tumor necrosis factor-α, interleukin [IL]-6, IL-8, IL-10, monocyte chemotactic protein [MCP]-1, IL-1 β, interferon-γ, IL-12p70, MCP-1α, IL-4, IL-2, and IL-13) were detected using the Luminex® technique.

Results: Concentrations of most cytokines were significantly higher in the shock group. When a cytokine storm intensity curve was considered with the vasopressor dependency index and a Sequential Organ Failure Assessment (SOFA) score, time point of maximum cytokine storm intensity was earlier than that of the maximum vasopressor dependency index and SOFA score in the shock group.

Conclusions: Cytokine storm occurred in patients with septic shock shortly after the abdominal surgery and may be a main mechanism leading to septic shock. Cytokine storm interventions should ideally be initiated within 24 h after surgery and be guided by cytokine storm biomarkers.

Role of Antithrombin III and Tissue Factor Pathway in the Pathogenesis of Sepsis

The pathobiology of the septic process includes a complex interrelationship between inflammation and the coagulations system. Antithrombin (AT) and tissue factor are important components of the coagulation system and have potential roles in the production and amplification of sepsis. Sepsis is associated with a decrease in AT levels, and low levels are also associated with the development of multiple organ failure and death. Treatment strategies incorporating AT replacement therapy in sepsis and septic shock have not resulted in an improvement in survival or reversal of disseminated intravascular coagulation.

Incidence, trends, and outcomes of infection sites among hospitalizations of sepsis: A nationwide study

Purpose

To determine the trends of infection sites and outcome of sepsis using a national population-based database.

Materials and methods

Using the Nationwide Inpatient Sample database of the US, adult sepsis hospitalizations and infection sites were identified using a validated approach that selects admissions with explicit ICD-9-CM codes for sepsis and diagnosis/procedure codes for acute organ dysfunctions. The primary outcome was the trend of incidence and in-hospital mortality of specific infection sites in sepsis patients. The secondary outcome was the impact of specific infection sites on in-hospital mortality.

Results

During the 9-year period, we identified 7,860,687 admissions of adult sepsis. Genitourinary tract infection (36.7%), lower respiratory tract infection (36.6%), and systemic fungal infection (9.2%) were the leading three sites of infection in patients with sepsis. Intra-abdominal infection (30.7%), lower respiratory tract infection (27.7%), and biliary tract infection (25.5%) were associated with highest mortality rate. The incidences of all sites of infections were trending upward. Musculoskeletal infection (annual increase: 34.2%) and skin and skin structure infection (annual increase: 23.0%) had the steepest increase. Mortality from all sites of infection has decreased significantly (trend p<0.001). Skin and skin structure infection had the fastest declining rate (annual decrease: 5.5%) followed by primary bacteremia (annual decrease: 5.3%) and catheter related bloodstream infection (annual decrease: 4.8%).

Conclusions

The anatomic site of infection does have a differential impact on the mortality of septic patients. Intra-abdominal infection, lower respiratory tract infection, and biliary tract infection are associated with higher mortality in septic patients.

Worldwide scientific productions with immunotherapy of sepsis: a bibliometric analysis

Background

Sepsis represents a significant healthcare problem worldwide and causes a high number of deaths every year but remains to be fully understood. During and after sepsis, the host immune response is complex and involves an initial excessive host inflammatory response to infection that is closely related to tissue damage and leads to organ failure. Over the past three decades, immunotherapy for sepsis has vastly improved, but in this area, the most influential articles, journals, authors, and countries have not yet been completely summarized and analyzed.

Objective

Performed a bibliometric analysis on all the articles concerning immunotherapy for sepsis from 1962 to 2019 was our objective, and we also explored the potential correlations between publications of different countries and their gross domestic product (GDP).

Methods

All articles about immunotherapy for sepsis were extracted from the Scopus database and analyzed. We also retrieved GDP data from all the countries that have published information from the World Bank.

Results

In summary, we have retrieved 1,483 related articles from the Scopus database starting from the first publication on immunotherapy for sepsis in 1962 through March 16, 2019. Over the past decade, the number of the articles published has increased year by year to reach 866 in total, which accounts for about 58% of all publications, with 2017 being the most prolific year when 179 articles were published. The US published 604 articles (41%), followed by China (n = 163, 11%), and Germany (n = 158, 11%). In terms of publishing media, the journal that published the highest number of the articles was Journal of Critical Care Medicine with 65 articles (4%), followed by Shock with 55 articles (4%), and Critical Care with 35 articles (2%). There was a strong correlation between the GDP of the different countries and their publication numbers (r = 0.811, P < 0.001).

Conclusions

Our present study analyzed all types of articles concerning immunotherapy for sepsis over the past 57 years and countries with high GDP tends to make more contributions to the medical field of this field. In the meantime, these studies highlight the importance of immunotherapy in the treatment of sepsis patients. The recognition of the historical status and development trend of this field can promote inter-agency cooperation, guide future research, and ultimately provide the basis for clinical practice guidelines.

Swiprosin-1 deficiency impairs macrophage immune response of septic mice

Despite the fact that many therapeutic strategies have been adopted to delay the development of sepsis, sepsis remains one of the leading causes of death in noncoronary intensive care units. Recently, sepsis-3 was defined as life-threatening organ dysfunction due to a dysregulated host response to infection. Here, we report that swiprosin-1 (also known as EFhd2) plays an important role in the macrophage immune response to LPS-induced or cecal ligation and puncture-induced (CLP-induced) sepsis in mice. Swiprosin-1 depletion causes higher mortality, more severe organ dysfunction, restrained macrophage recruitment in the lung and kidney, and attenuated inflammatory cytokine production (including IL-1β, IL-6, TNF-α, IL-10, and IFN-γ). The immunosuppression caused by swiprosin-1 deficiency is manifested by impaired bactericidal capacity and decreased HLA-DR expression in macrophages. Swiprosin-1 affects the activation of the JAK2/STAT1/STAT3 pathway by regulating the expression of IFN-γ receptors in macrophages. Our findings provide a potential target for the regulation of the macrophage immune response in sepsis.

Vitamin C: The next step in sepsis management?

Sepsis is a life-threatening medical condition, affecting approximately 26 million people worldwide every year. The disease is a continuum, marked by dysregulated inflammation and hemodynamic instability leading to shock, multi-system organ dysfunction, and death. Over the past decades, there has been a focus on the early identification and treatment of sepsis primarily with bundled and goal directed therapy. Despite these advances, morbidity and mortality has remained high, prompting investigation into novel therapies. Vitamin C is a water-soluble vitamin that plays a role in mediating inflammation through antioxidant activities and is also important in the synthesis of cortisol, catecholamines, and vasopressin, which are key mediators in the disease process. Emerging evidence provides cursory data in support of the administration of vitamin C in addition to standard therapy to ameliorate the effects of inflammation and improve hemodynamic stability in patients with sepsis and septic shock; however, further evidence is needed to support this practice. This review discusses the physiologic role of vitamin C as well as the recent literature and evidence for the use of vitamin C in patients presenting with sepsis.