Papel de las quimioquinas solubles circulantes en el shock séptico

CTC-177, a novel drug-Fc conjugate, shows promise as an immunoprophylactic agent against multidrug-resistant Gram-negative bacterial infections

Background

The widespread emergence of antibiotic resistance including MDR in Gram-negative bacterial pathogens poses a critical challenge to the current antimicrobial armamentarium.

Objectives

To create a novel drug-Fc conjugate (DFC) that can be delivered at sustained and prolonged levels while simultaneously activating the host immune response to combat MDR Gram-negative infections.

Methods

The Cloudbreak™ platform was used to develop DFCs consisting of a targeting moiety (TM) (a polymyxin-derived dimer) attached via a non-cleavable linker to an effector moiety (EM) (the Fc domain of human IgG1). In vitro activities of the DFCs were assessed by MIC testing. Neutropenic mouse models of thigh infection, septicaemia and pneumonia were used to evaluate in vivo efficacy. Pharmacokinetics were evaluated in mice and cynomolgus monkeys.

Results

A single prophylactic dose of our lead DFC, CTC-177, resulted in significantly decreased bacterial burdens and reduced inflammation comparable to daily treatment with colistin in septicaemia and pneumonia mouse models. Furthermore, CTC-177 prophylaxis was able to restore colistin efficacy in colistin-resistant septicaemia, reducing bacterial burdens beyond the limit of detection. Finally, CTC-177 displayed a long terminal half-life of over 24 and 65 h in mice and cynomolgus monkeys, respectively.

Conclusions

These data support the continued development of Cloudbreak™ DFCs as broad-spectrum prophylactic agents against Gram-negative infections.

Natural history and profile of selective cytokines in patients of acute pancreatitis with acute kidney injury

OBJECTIVES

To study the natural course of patients with acute pancreatitis (AP) with acute kidney injury (AKI) and their cytokine profile.

METHODS

Natural course of patients with AP and AKI was studied in 97 individuals. Levels of TNFα, IL-6, IL-10, IL-8 and IL-1β were measured at presentation and at 72 h in patients who developed AKI.

RESULTS

Amongst the entire cohort, 16.4% patients developed AKI (persistent AKI - 11 patients, transient AKI - 5 patients). Mortality rate was 25% amongst patients with AKI. Levels of IL-6 (p = 0.035) and IL-8 (p = 0.002) were found to be significantly higher in the AKI group. On multivariate analysis, IL-8 levels at baseline were found to be an independent predictor of AKI. AKI group had significant rise of TNF-α (P < 0.001), IL-6 (P < 0.001) and IL- 1β (P < 0.001) on day 3 whereas persistent-AKI group had significant rise of TNF-α (p = 0.031), IL-6 (p = 0.001) and IL-1β on day 3 and significant decline of IL-10 (p = 0.015). Using a cut-off of 105 pg/ml, IL-8 levels at baseline could predict AKI with a sensitivity of 87.5% and specificity of 59.2%, with area under the curve being 0.744 (p = 0.002).

CONCLUSION

AP patients developing AKI have poor prognosis. IL-8 levels can predict AKI in patients with AP.

CXCL8(3-72) K11R/G31P protects against sepsis-induced acute kidney injury via NF-κB and JAK2/STAT3 pathway

Background

Acute kidney injury (AKI), which is mainly caused by sepsis, has high morbidity and mortality rates. CXCL8_(3–72) K11R/G31P (G31P) can exert therapeutic effect on inflammatory diseases and malignancies. We aimed to investigate the effect and mechanism of G31P on septic AKI.

Methods

An AKI mouse model was established, and kidney injury was assessed by histological analysis. The contents of serum creatinine (SCr) and blood urea nitrogen (BUN) were measured by commercial kits, whereas neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) were detected by enzyme-linked immunosorbent assay (ELISA) kits. The expressions of CXCL8 in serum and kidney tissues were determined using ELISA and immunohistochemical analysis, respectively. Apoptosis rate of renal tissue was detected by terminal deoxynucleotidyl transfer-mediated dUTP nick end labeling (TUNEL) analysis. The expressions of inflammatory cytokines were measured by quantitative real-time PCR and Western blot, respectively. The apoptosis-related proteins, JAK2, STAT3, NF-κB and IκB were determined by Western blot.

Results

G31P could reduce the levels of SCr, BUN, HGAL and KIM-1 and inhibit the renal tissue injury in AKI mice. G31P was also found to suppress the serum and nephric CXCL8 expressions and attenuated the apoptosis rate. The levels of inflammatory cytokines, pro-apoptotic proteins were decreased, while the anti-apoptotic proteins were increased by G31P in AKI mice. G31P also inhibited the activation of JAK2, STAT3 and NF-κB in AKI mice.

Conclusion

These results suggest that G31P could protect renal function and attenuate the septic AKI. Our findings provide a potential target for the treatment of AKI.

Interleukin-8 and Tumor Necrosis Factor Predict Acute Kidney Injury After Pediatric Cardiac Surgery

BACKGROUND

Inflammation is a key component of both acute kidney injury (AKI) and response to cardiopulmonary bypass. Because AKI poses risks to children after cardiac surgery, we investigated the value of inflammatory biomarkers interleukin-8 (IL-8) and tumor necrosis factor alpha (TNFα) for predicting AKI and other complications.

METHODS

We enrolled 412 children between the ages of 1 month and 18 years undergoing cardiopulmonary bypass for cardiac surgery. We collected blood both preoperatively and postoperatively (within 6 hours post-surgery) and measured plasma IL-8 and TNFα.

RESULTS

IL-8 and TNFα did not predict AKI in children <2 years, but were strongly associated with AKI in children ≥2 years. There were significant associations between biomarker levels and age (<2 or ≥2 years). In children ≥2 years, patients in the highest tertile of preoperative IL-8 and postoperative TNFα had 4.9-fold (95% CI: 1.8-13.2) and 3.3-fold (95% CI: 1.2-9.0) higher odds of AKI compared with those in the lowest tertile. Children <2 years with higher biomarker levels also had higher odds of AKI, but the difference was not significant. We also found that postoperative TNFα levels were significantly higher in patients with longer hospital stays, and that both postoperative IL-8 and TNFα levels were significantly higher in patients with longer ventilation lengths. There was no evidence that biomarker levels mediated the association between AKI and length of ventilation; they appear to be independent predictors.

CONCLUSIONS

Preoperative IL-8 and postoperative TNFα are significantly associated with higher odds of AKI and greater lengths of hospital stays and ventilator use in children 2 years and older.

Role of circulating lymphocytes in patients with sepsis

Sepsis is a systemic inflammatory response syndrome due to infection. The incidence rate is estimated to be up to 19 million cases worldwide per year and the number of cases is rising. Infection triggers a complex and prolonged host response, in which both the innate and adaptive immune response are involved. The disturbance of immune system cells plays a key role in the induction of abnormal levels of immunoregulatory molecules. Furthermore, the involvement of effector immune system cells also impairs the host response to the infective agents and tissue damage. Recently, postmortem studies of patients who died of sepsis have provided important insights into why septic patients die and showed an extensive depletion of CD4 and CD8 lymphocytes and they found that circulating blood cells showed similar findings. Thus, the knowledge of the characterization of circulating lymphocyte abnormalities is relevant for the understanding of the sepsis pathophysiology. In addition, monitoring the immune response in sepsis, including circulating lymphocyte subsets count, appears to be potential biomarker for predicting the clinical outcome of the patient. This paper analyzes the lymphocyte involvement and dysfunction found in patients with sepsis and new opportunities to prevent sepsis and guide therapeutic intervention have been revealed.