Influence of surgery and endotoxin-induced sepsis combined on natural killer cell activity, oxidative burst of granulocytes and antigen presentation capability of monocytes

Application of a novel microscopic technique for quantifying CA125 binding to circulating mononuclear cells in longitudinal specimens during treatment for ovarian cancer

Background

Measurement of serum CA125, an antigenic fragment of human mucin 16 (MUC16), is used to monitor the clinical progression of epithelial ovarian cancer (EOC). However, rather than simply a passive marker reflecting tumor burden, MUC16 may have a more active role by binding to immune cells and altering their tumor response. We developed a research tool to measure MUC16-binding to the surfaces of peripheral blood mononuclear cell (PBMC) subtypes and tested its research value using specimens collected serially from a woman being treated for high grade serous EOC.

Methods

Cryopreserved PBMCs were mixed with anti-CA125 antibody-labeled plasmonic gold nanoparticles (PNPs) to detect cell surface MUC16-binding along with fluorescent stains to identify B cells, NK cells, NK-T cells, T cells, and monocytes. From 3D darkfield images, a computer algorithm was applied to enumerate PNP-binding and fluorescence microscopy to identify cell lineage. Average MUC16-binding was determined by fitting a Poisson distribution to PNP-counts across similar cell types. MUC16-binding to cell types was correlated with treatment details, CA125 levels, and complete blood count (CBC) data.

Results

Over a 21-month period, monocytes had the highest level of MUC16-binding which was positively correlated with serum CA125 and inversely correlated with circulating monocyte and lymphocyte counts. Fluctuations of PNP-binding to NK cells were associated temporally with types of chemotherapy and surgical events. Levels of MUC16 bound to NK cells were positively correlated with levels of MUC16 bound to T and NK-T cells and inversely correlated with circulating platelets.

Conclusions

Assessment of MUC16-binding among cryopreserved PBMC cell types can be accomplished using darkfield and fluorescence microscopy. Correlations observed between level of binding by cell type with serum CA125, CBC data, and treatment details suggest that the new techniques may offer novel insights into EOC’s clinical course.

A Machine Learning-Based Prediction of Hospital Mortality in Patients With Postoperative Sepsis

Introduction: The incidence of postoperative sepsis is continually increased, while few studies have specifically focused on the risk factors and clinical outcomes associated with the development of sepsis after surgical procedures. The present study aimed to develop a mathematical model for predicting the in-hospital mortality among patients with postoperative sepsis. Materials and Methods: Surgical patients in Medical Information Mart for Intensive Care (MIMIC-III) database who simultaneously fulfilled Sepsis 3.0 and Agency for Healthcare Research and Quality (AHRQ) criteria at ICU admission were incorporated. We employed both extreme gradient boosting (XGBoost) and stepwise logistic regression model to predict the in-hospital mortality among patients with postoperative sepsis. Consequently, the model performance was assessed from the angles of discrimination and calibration. Results: We included 3,713 patients who fulfilled our inclusion criteria, in which 397 (10.7%) patients died during hospitalization, and 3,316 (89.3%) patients survived through discharge. Fluid-electrolyte disturbance, coagulopathy, renal replacement therapy (RRT), urine output, and cardiovascular surgery were important features related to the in-hospital mortality. The XGBoost model had a better performance in both discriminatory ability (c-statistics, 0.835 vs. 0.737 and 0.621, respectively; AUPRC, 0.418 vs. 0.280 and 0.237, respectively) and goodness of fit (visualized by calibration curve) compared to the stepwise logistic regression model and baseline model. Conclusion: XGBoost model has a better performance in predicting hospital mortality among patients with postoperative sepsis in comparison to the stepwise logistic regression model. Machine learning-based algorithm might have significant application in the development of early warning system for septic patients following major operations.

Influence of Postoperative Enteral Nutrition on Cellular Immunity: Investigative Procedures, Tests and Analysis

“Postoperative enteral nutrition and cellular immunity” is mostly described in the literature on research into surgical complications. The intention is to show whether a given treatment can be identified as having a beneficial clinical effect and to demonstrate this by the effect on, among other factors, cellular immunity.

In order to show that the inclusion of a particular nutrient would have a beneficial effect on cellular immunity, and thus the postoperative course, the research is often related to various types of postoperative immuno-nutrition.

This chapter will briefly describe various types of immuno-nutrition and the influence of the added nutrients on cellular immunity.

In describing cellular immunity, many different lymphocyte subpopulations have been used, along with markers to describe their activity. As all the different subpopulations can be difficult to remember and understand, the aim of this chapter is to give the reader a short overview of the cellular immunity aspects.

It will also give a brief overview of the two types of cells most often described in the literature and their function in the immune response.

Many articles indicate the subpopulations of different lymphocyte groups in percentages, making it difficult to understand the comparisons between the different phases of, for example, a postoperative course. This chapter will provide a summary of the investigative procedures described in the literature and explain how to proceed with tests and analyses and how to specify the results so that they can be used to compare the results obtained at different times during the test period.

A brief description of the flow cytometric method has therefore been included to give the reader an understanding of how the number of subpopulation percentages is indicated.

Influence of postoperative enteral nutrition on cellular immunity. A random double-blinded placebo controlled clinical trial

PURPOSE

The aim of this study was to discover if the cellular immunological response is different in patients receiving early postoperative enteral nutrition compared to patients who only receive "water".

METHODS

In a random double-blind prospective trial, 30 patients received Nutridrink® and 30 patients received placebo (water) through a nasoduodenal tube from the day of operation to the fourth postoperative day. Leukocyte differential count was examined preoperatively, and on the first, third, and seventh postoperative days. Subpopulations of lymphocytes were flow cytometrically analysed. IL-1ra and soluble IL-2R were investigated by use of an enzyme-linked immunosorbent assay.

RESULTS

In the enteral nutrition group, a significantly larger number of circulating monocytes and NK-cells and a significantly larger expression of HLA-DR were found. In the nutrition group, a tendency to larger numbers of T-lymphocyte subpopulations was found. No difference in IL-1ra and soluble IL-2R was found between the groups.

CONCLUSION

Early postoperative enteral nutrition has an important influence on the immediate unspecific cellular immunity and an activating effect on the specific cellular immunity compared to "no food".

Postoperative sepsis

PURPOSE OF REVIEW

Postoperative sepsis is a major cause of surgical associated morbidity and mortality. Our goal is to describe its incidence, pathophysiology, and contributing factors. In addition, we will review preventive measures and treatment options that may possibly reduce its healthcare burden.

RECENT FINDINGS

We review epidemiologic data and clinical tools presented in multiple current studies, which may help lower incidence and improve outcome of postoperative sepsis.

SUMMARY

The incidence of postoperative sepsis has not declined over the past years, although mortality is trending downwards. Several biochemical and genetic markers may allow early diagnosis. Prevention and prompt treatment may lower mortality.

Effect of renal and non-renal ischemia/reperfusion on cell-mediated immunity in organs and plasma

Acute renal failure (ARF) is a common morbidity factor among patients in the intensive care unit, reaching an incidence from 3% to 30% depending on the definition of ARF and the population. Although the majority of the patients with ARF are treated with continuous renal replacement therapy, the mortality rate still remains above 50%. The causes of death are primarily extra-renal and include infection, shock, septicemia, and respiratory failure. We wanted to evaluate the cell-mediated inflammatory response of renal ischemia-reperfusion (I/R) and non-renal I/R, in blood and in distant organs. In our study, 80 mice were divided into four groups. The following surgeries were performed on the groups compared: bilateral renal I/R by clamping, unilateral renal ischemia, anesthesia only, and unilateral hind leg I/R. Half of the animals were killed after 2 h and the other half after 24 h. To assess the inflammatory response, we measured myeloperoxidase (MPO) in the organs, and CD 11b and major histocompatibility complex (MHC) II-positive cells in the blood. Non-renal I/R elicited the most elevated levels of MPO in extra-renal tissue such as the lungs. There was a trend toward higher MPO levels in the kidney following renal I/R. All kinds of I/R induced an upregulation of the adhesion molecule CD 11b and a downregulation of MHC II. Renal and non-renal I/R induced neutrophil infiltration in distant organs. Renal I/R does not induce a larger cell-mediated inflammatory response in blood and organs than non-renal I/R.

Perioperative gene expression analysis for prediction of postoperative sepsis

BACKGROUND

Postoperative sepsis is one of the main causes of death after major abdominal surgery; however, the immunologic factors contributing to the development of sepsis are not completely understood. In this study, we evaluated gene expression in patients who developed postoperative sepsis and in patients with an uncomplicated postoperative course.

METHODS

We enrolled 220 patients in a retrospective matched-pair, case-control pilot study to investigate the perioperative expression of 23 inflammation-related genes regarding their properties for predicting postoperative sepsis. Twenty patients exhibiting symptoms of sepsis in the first 14 days after surgery (case group) were matched with 20 control patients with an uncomplicated postoperative course. Matching criteria were sex, age, main diagnosis, type of surgery, and concomitant diseases. Blood samples were drawn before surgery and on the first and second postoperative days. Relative gene expression was analyzed with real-time reverse-transcription PCR.

RESULTS

Significant differences (P < 0.005) in gene expression between the 2 groups were observed for IL1B (interleukin 1, beta), TNF [tumor necrosis factor (TNF superfamily, member 2)], CD3D [CD3d molecule, delta (CD3-TCR complex)], and PRF1 [perforin 1 (pore forming protein)]. Logistic regression analysis and a subsequent ROC curve analysis revealed that the combination of TNF, IL1B, and CD3D expression had a specificity and specificity of 90% and 85%, respectively, and predicted exclusion of postoperative sepsis with an estimated negative predictive value of 98.1%.

CONCLUSIONS

These data suggest that gene expression analysis may be an effective tool for differentiating patients at high and low risk for sepsis after abdominal surgery.

The extent of thermal injury affects fractions of mononuclear cells

BACKGROUND

The mononuclear cell (MNC) fraction contains a variety of cell types, including stem cells such as endothelial progenitor cells (EPCs). EPC can rapidly revascularise ischaemic areas, but their role in burns is unclear.

AIM

This study investigates how thermal injury to the skin might influence mononuclear cells, CD34(+) cells and circulating EPC.

METHODS

The study group comprised 17 people with burns and 17 age-matched controls. Blood samples were collected at five different time points during the first 5 days of hospitalisation. Clinical parameters and scores were documented as well as cell counts for MNC, CD34(+) cells and EPC. Counts were quantified by fluorescence-activated cell sorting. Serum was tested for vascular endothelial growth factor VEGF(165) by ELISA.

RESULTS

All cell populations displayed significant, differing changes in counts and percentages after burn. These effects varied markedly over time and expressed different patterns if clinical scores were subjected to significance testing. EPC counts were significantly lowered in cases with fatal outcome.

CONCLUSION

Burn affects the numbers of circulating MNC, CD34(+) and EPC. These time-dependent changes imply involvement of these cell groups in the trauma. EPC counts seem to be a predictive factor for outcome of cases of severe burn.

The impact of long-term haemofiltration (continuous veno-venous haemofiltration) on cell-mediated immunity during endotoxaemia

BACKGROUND

Increased survival with high-volume continuous veno-venous haemofiltration (CVVH) has been demonstrated in critically ill patients. This may be the result of intensified blood purification or an effect on the immune system. We hypothesized that CVVH modifies the cell-mediated immunity. We investigated the effect of high-volume CVVH for 24 h on the cell-mediated immunity following endotoxin infusion.

METHODS

Thirty pigs were divided into three groups. Ten pigs received 30 microg/kg of Escherichia coli endotoxin. These pigs were treated with CVVH (replacement 35 ml/kg/h) over the following 24 h. Ten pigs received the same bolus of endotoxin and ten pigs served as a control group. The adhesion molecules CD18, CD44 and CD62L and the ability to respond with an oxidative burst were measured. The number of neutrophils was counted in blood and lung tissue. The lymphoproliferative response and cytokines interleukin-6 and interleukin-10 were measured.

RESULTS

The infusion of endotoxin was followed by initial granulocytopenia and, later, granulocytosis, activation of CD18 and CD62L, and increased oxidative burst. The cytokine level was increased. CVVH had no effect on the adhesion molecules or cytokine level and did not reduce the number of granulocytes in the lung significantly. CVVH, however, reduced the oxidative burst activity of neutrophils after 2 h of treatment.

CONCLUSION

In the first few hours after endotoxaemia, high-volume CVVH reduced the oxidative burst activity of neutrophils. However, in the long term, CVVH was unable to modify the endotoxin-induced changes in cell-mediated immunity.

The post-operative level of serum monocyte chemoattractant protein-1 and its correlation with the severity of surgical stress

BACKGROUND

Several basic studies have demonstrated that monocyte chemoattractant protein-1 (MCP-1) influences type 2 cytokine production and cell-mediated immunity. However, there have been few reports on the changes in serum MCP-1 levels in patients undergoing major thoracoabdominal surgery. In this study, we examined the kinetics of serum MCP-1 post-operatively and clarified its significance regarding the extent of surgical stress.

MATERIALS AND METHODS

Seventeen patients who underwent surgical operations were included in this study. All of them were fed by total parenteral nutrition to deliver the same amount of calories and nitrogen. Of the severely stressed group, nine patients underwent esophagectomy with thoracotomy. Of the group of moderately stressed group, eight patients underwent gastric or colorectal surgery. Serum MCP-1 and interleukin-6 (IL-6) were measured after operation. Cell-mediated immunity was measured by concanavalin A- or phytohemagglutinin-stimulated lymphocyte proliferation on the seventh post-operative day.

RESULTS

Serum MCP-1 and IL-6 were increased immediately after surgery in both groups. The level of MCP-1 was significantly higher in the group of severely stressed patients than in the moderately stressed group. Concanavalin A or phytohemagglutinin-stimulated lymphocyte proliferation was significantly lower in the severely stressed group than in the moderately stressed group.

CONCLUSIONS

These results indicate that serum MCP-1 levels are directly correlated, and cell-mediated immunity inversely correlated, with the severity of surgical stress.