Modulation of cytokine-induced production of IL-8 in vitro by interferons and glucocorticosteroids

PFOA, PFHxA and C6O4 differently modulate the expression of CXCL8 in normal thyroid cells and in thyroid cancer cell lines

Industrial chemical PFAS are persistent pollutants. Long chain PFAS were taken out of production due to their risk for human health, however, new congeners PFAS have been introduced. The in vitro effects of the long-chain PFOA, the short-chain PFHxA and the new-generation C6O4 were evaluated in normal and in thyroid cancer cell lines in terms of cell viability and proliferation, and secretion of a pro-tumorigenic chemokine (CXCL8), both at the mRNA and at the protein level. The Nthy-ory 3-1 normal-thyroid cell line, the TPC-1 and the 8505C (RET/PTC rearranged and BRAFV600e mutated, respectively) thyroid-cancer cell lines were exposed to increasing concentrations of each PFAS in a time-course. We evaluated viability using WST-1 (confirmed by AnnexinV/PI) and proliferation using the cristal-violet test. To evaluate CXCL8 mRNA we used RT-PCR and measured CXCL8 in the supernatants by ELISA. The exposure to none PFAS did not affect thyroid cells viability (except for a reduction of 8505C cells viability after 144 h) or proliferation. Individual PFAS differently modulated CXCL8 mRNA and protein level. PFOA increased CXCL8 both at mRNA and protein level in the three cell lines; PFHxA increased CXCL8 mRNA in the three cell lines, but increased the protein only in TPC-1 cells; C6O4 increased the CXCL8 mRNA only in thyroid cancer cell lines, but never increased the CXCL8 protein. The results of the present study indicate that the in vitro exposure to different PFAS may modulate both at the mRNA and secreted protein levels of CXCL8 in normal and cancer thyroid cells. Strikingly different effects emerged according to the specific cell type and to the targeted analyte (CXCL8 mRNA or protein).

bFGF and collagen matrix hydrogel attenuates burn wound inflammation through activation of ERK and TRK pathway

Burn injuries are most challenging to manage since it causes loss of the integrity of large portions of the skin leading to major disability or even death. Over the years, hydrogels are considered as a significant delivery system for wound treatment because of several advantages over other conventional formulations. We hypothesized that the bFGF-collagen-AgSD incorporated hydrogel formulation can accelerate the rate of burn healing in animal model and would promote fibroblast cell proliferation. Neovascularization and re-epithelialization is a hall mark of burn wound healing. In the present study, histopathological investigation and scanning electron microscopy of skin tissue of Wistar rats showed almost complete epithelialisation after 16 days in the treatment group. The developed hydrogel showed significantly accelerated wound closure compared with a standard and control group. The faster wound closure resulted from increased re-epithelialization and granulation tissue formation because of the presence of collagen and growth factor. Expressions of proteins such as TrkA, p- TrkA, ERK1/2, p-ERK1/2, NF-kβ, and p-NF-kβ involved in nerve growth factor (NGF) signalling pathway were analysed by western blot. All the findings obtained from this study indicated that the hydrogel can be considered as a promising delivery system against second degree burn by faster healing.

The role of nicotinic receptors in SARS-CoV-2 receptor ACE2 expression in intestinal epithelia

BACKGROUND

Recent evidence demonstrated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) propagates in intestinal epithelial cells expressing Angiotensin-Converting Enzyme 2 (ACE2), implying that these cells represent an important entry site for the viral infection. Nicotinic receptors (nAChRs) have been put forward as potential regulators of inflammation and of ACE2 expression. As vagus nerve stimulation (VNS) activates nAChRs, we aimed to investigate whether VNS can be instrumental in affecting intestinal epithelial ACE2 expression.

METHODS

By using publicly available datasets we qualified epithelial ACE2 expression in human intestine, and assessed gene co-expression of ACE2 and SARS-CoV-2 priming Transmembrane Serine Protease 2 (TMPRSS2) with nAChRs in intestinal epithelial cells. Next, we investigated mouse and human ACE2 expression in intestinal tissues after chronic VNS via implanted devices.

RESULTS

We show co-expression of ACE2 and TMPRSS2 with nAChRs and α7 nAChR in particular in intestinal stem cells, goblet cells, and enterocytes. However, VNS did not affect ACE2 expression in murine or human intestinal tissue, albeit in colitis setting.

CONCLUSIONS

ACE2 and TMPRSS2 are specifically expressed in epithelial cells of human intestine, and both are co-expressed with nAChRs. However, no evidence for regulation of ACE2 expression through VNS could be found. Hence, a therapeutic value of VNS with respect to SARS-CoV-2 infection risk through ACE2 receptor modulation in intestinal epithelia could not be established.

Dexamethasone inhibits cytokine production in PBMC from systemic sclerosis patients

Glucocorticoids (GC) are widely used in the treatment of SSc, although there is not much evidence to prove the benefits offered by these drugs in this disease. In this study, we evaluated the effects of a GC on cytokine production in peripheral blood mononuclear cells (PBMC) of SSc patients. The effect of dexamethasone (DEX) was evaluated in PBMC of 21 SSc patients and 10 healthy volunteers after stimulation of cells with anti-CD3 and anti-CD28. Cytokines IL-2, IL-4, IL-6, IL-10, IL-17A, IL-17F, IFN-γ, TNF, and IL-1β were quantified in the culture supernatant by CBA or ELISA. Of the patients evaluated in this study, 8 (38%) were taking corticosteroids, and esophageal dysfunction was more frequent in these patients when compared to those who did not take corticosteroids. DEX (1.000 nM) treatment in PBMC of SSc patients stimulated with anti-CD3 and anti-CD28 promoted a significant reduction in IL-2, IL-4, IL-6, IL-10, IL-17A, IFN-γ, TNF, IL-1β (p < 0.001 for all), and IL-17F (p = 0.023) cytokines levels. We did not observe differences in response to in vitro treatment with DEX between groups of patients taking or not taking corticosteroids. In PBMC from healthy volunteers, we observed that DEX treatment significantly reduced IL-4, IFN-γ (p = 0.003 for both), IL-6, IL-10, IL-17A, and TNF (p = 0.002 for all) cytokines. These results show that DEX treatment in PBMC of SSc patients reduced the production of important cytokines involved in the pathogenesis of the disease, suggesting a possible mechanism of action of the CG in the treatment of SSc.

Corticosteroid inhibits chemokines production in systemic sclerosis patients

In this study, we evaluated glucocorticoids (GC) effects on cytokine/chemokine levels in serum samples and peripheral blood mononuclear cell (PBMC) production from systemic sclerosis (SSc) patients. We evaluated cytokine and chemokine levels in serum samples from SSc patients taking or not taking systemic glucocorticoids. PBMCs response to methylprednisolone (MP) was examined from 15 SSc patients and 8 healthy control subjects following PBMC stimulation with anti-CD3/CD28. Cytokine (IFN-γ, TNF, IL-2, IL-4, IL-6, IL-10, and IL-17A) and chemokine (CXCL8/IL-8, CCL5/RANTES, CXCL9/MIG, CCL2/MCP-1, and CXCL10/IP-10) levels were quantified in serum and in PBMC culture supernatants by CBA or ELISA. Compared with patients not taking corticosteroids, we did not observe any significant differences in cytokines/chemokines serum levels in patients using systemic corticosteroids. After stimulation with anti-CD3/CD28, PBMCs treated with MP (100μM), showed a significant reduction of CCL2/MCP-1 (p=0.001), CCL5/RANTES (p=0.04), and CXCL8/IL-8 (p=0.003) levels in SSc patients. In PBMC from healthy controls, we observed decreased IFN-γ, TNF, IL-2, and IL-10 levels after MP treatment, compared with stimulated condition (p<0.01 for all). However in SSc patients, we did not find any significant reduction in these cytokine levels after MP treatment. In conclusion, CCL2/MCP-1, CCL5/RANTES, and CXCL8/IL-8 are chemokines that are potentially modulated by corticosteroids in vitro in SSc patients, but no effect was observed on IL-2, IL-4, IL-6, IL-10, IL-17A, TFN, and IFN-γ secretion. These results suggest a potential effect of GCs on SSc treatment and may reflect the benefit of their use in some patients.

Impaired Immune Response in Elderly Burn Patients: New Insights Into the Immune-senescence Phenotype

OBJECTIVE

Comparing the inflammatory and immunological trajectories in burned adults versus burned elderly patients to gain novel insights and better understanding why elderly have poor outcomes.

SUMMARY BACKGROUND DATA

Despite receiving the same treatment and clinical consideration as all other burn patients, elderly patients continue to have substantially poorer outcomes compared with adults. In light of an aging population, gaining a better understanding of their susceptibility to complications and creating new treatment strategies is imperative.

METHODS

We included 130 burn patients (94 adults: <65 years old and 36 elderly: ≥65 years old) and 10 healthy controls in this study. Immune activity and expression was assessed using bioplex at various time points. Clinical outcomes such as infection, sepsis, and mortality were prospectively collected.

RESULTS

Elderly burn patients had significantly lower burn size but significantly higher Baux scores. Morbidity and mortality was significantly increased in the elderly cohort. Immune biomarkers indicated that elderly are immune compromised and unable to respond with the expected inflammatory response during the early phase after injury. This trajectory changes to a hyperinflammatory pattern during the later phase after burn. These findings are even more pronounced when comparing sepsis versus nonsepsis patients as well as survivors versus nonsurvivors in the elderly.

CONCLUSIONS

Elderly burned patients mount a delayed immune and dampened inflammatory response early after burn injury that changes to an augmented response at later time points. Late-onset sepsis and nonsurvivors had an immune exhaustion phenotype, which may represent one of the main mediators responsible for the striking mortality in elderly.

Altered microRNA and gene expression in the follicular fluid of women with polycystic ovary syndrome

PURPOSE

To determine if microRNAs are differentially expressed in the follicular fluid of women with PCOS compared to fertile oocyte donors and identify associated altered gene expression.

METHODS

Women undergoing IVF who met Rotterdam criteria for PCOS or who were fertile oocyte donors were recruited from a private IVF center. Individual follicle fluid was collected at the time of oocyte retrieval. MicroRNA analysis was performed using microarray and validated using real-time PCR on additional samples. Potential gene targets were identified and their expression analyzed by real time PCR.

RESULTS

Microarray profiling of human follicular fluid revealed expression of 235 miRNAs, 29 were differentially expressed between the groups. Using PCR validation, 5 miRNAs (32, 34c, 135a, 18b, and 9) showed significantly increased expression in the PCOS group. Pathway analysis revealed genes involved in insulin regulation and inflammation. Three potential target genes were found to have significantly decreased expression in the PCOS group (interleukin 8, synaptogamin 1, and insulin receptor substrate 2).

CONCLUSIONS

MicroRNAs are differentially expressed in the follicular fluid of women with PCOS when compared to fertile oocyte donors. There is also altered expression of potential target genes associated with the PCOS phenotype.

Long-term persistance of the pathophysiologic response to severe burn injury

Background

Main contributors to adverse outcomes in severely burned pediatric patients are profound and complex metabolic changes in response to the initial injury. It is currently unknown how long these conditions persist beyond the acute phase post-injury. The aim of the present study was to examine the persistence of abnormalities of various clinical parameters commonly utilized to assess the degree hypermetabolic and inflammatory alterations in severely burned children for up to three years post-burn to identify patient specific therapeutic needs and interventions.

Methodology/Principal Findings

Patients: Nine-hundred seventy-seven severely burned pediatric patients with burns over 30% of the total body surface admitted to our institution between 1998 and 2008 were enrolled in this study and compared to a cohort non-burned, non-injured children. Demographics and clinical outcomes, hypermetabolism, body composition, organ function, inflammatory and acute phase responses were determined at admission and subsequent regular intervals for up to 36 months post-burn. Statistical analysis was performed using One-way ANOVA, Student's t-test with Bonferroni correction where appropriate with significance accepted at p<0.05. Resting energy expenditure, body composition, metabolic markers, cardiac and organ function clearly demonstrated that burn caused profound alterations for up to three years post-burn demonstrating marked and prolonged hypermetabolism, p<0.05. Along with increased hypermetabolism, significant elevation of cortisol, catecholamines, cytokines, and acute phase proteins indicate that burn patients are in a hyperinflammatory state for up to three years post-burn p<0.05.

Conclusions

Severe burn injury leads to a much more profound and prolonged hypermetabolic and hyperinflammatory response than previously shown. Given the tremendous adverse events associated with the hypermetabolic and hyperinflamamtory responses, we now identified treatment needs for severely burned patients for a much more prolonged time.

Characterization of the inflammatory response during acute and post-acute phases after severe burn

Severe burn causes a pronounced hypermetabolic response characterized by catabolism and extensive protein wasting. We recently found that this hypermetabolic state is driven by a severe inflammatory response. We characterized in detail the kinetics of serum levels of a panel of cytokines in a rat model, which may serve as reference for the development of therapeutic interventions applicable to humans. Male Sprague-Dawley rats (n = 8) received a full-thickness burn of 60% total body surface area. Serum was harvested 1, 3, 6, 12, 24, 48, 96, and 168 h after burn. Eight serum cytokines commonly used to assess the inflammatory response in humans, such as IL-1beta, IL-6, IL-10, TNF, vascular endothelial growth factor, and monocyte chemotactic protein 1, and the rat-specific cytokines cytokine-induced neutrophil chemoattractant (CINC) 1, CINC-2, and CINC-3 were measured by enzyme-linked immunosorbent assay technique and were compared with controls (n = 4). Statistical analysis was conducted using the t test, with P < 0.05 considered as significantly different. Thermal injury resulted in significantly increased serum levels of IL-1beta, IL-6, IL-10, monocyte chemotactic protein 1, CINC-1, CINC-2, and CINC-3 when compared with the concentrations detected in nonburned rats (P < 0.05). Serum levels of TNF-alpha and vascular endothelial growth factor in burned rats were not found to be significantly different to controls. Burn causes a profound inflammatory response in rats. Specific cytokines known to increase in humans postburn such as IL-1 beta, IL-6, IL-10, MCP-1, and IL-8 (CINC-1, CINC-2, and CINC-3 in the rat) were also observed in our rat burn model, which now allows us to study new anti-inflammatory treatment options.

Comparison of whole blood interleukin-8 and plasma interleukin-8 as a predictor for sepsis in postoperative patients

OBJECTIVE

Interleukin-8 (IL-8, also known as neutrophil-activating peptide 1, NAP1 and CXCL8, CXC chemokine ligand 8) is recognized as a potent effector of neutrophil functions. IL-8 is a major response factor following NfkB activation by cytokines or lipopolysaccharide and several different cell types T lymphocytes, monocytes, epithelial and endothelial cells secrete this polypeptide. IL-8 is not to be determined at significant concentrations in plasma due to its receptor binding but may play a major role in tissues. The prediction of sepsis is a major and current field of research in the treatment of surgical patients. The aim of this study was to compare the determination of IL-8 in whole blood cell lysates (whole blood IL-8) and in plasma for the prediction of sepsis in postoperative intensive care.

DESIGN

Whole blood IL-8, IL-8 in plasma, and CRP were measured in the daily routine monitoring of 84 patients in a surgical intensive care unit. Sepsis was defined by the criteria of the Society of Critical Care Medicine (SCCM). For comparison the APACHE II score (APACHE=Acute Physiology and Chronic Health Evaluation) was calculated. The diagnostic value of the three tests was compared by receiver operating characteristic (ROC) curves.

RESULTS

Whole blood IL-8 showed higher areas under the curve (AUC) than IL-8 in plasma and CRP. The ROC curves for the APACHE II scores gave similar results.

CONCLUSIONS

Sepsis is a complex disease and is induced by systemic infection of patients suffering from systemic inflammatory response syndromes (SIRS). Therefore, the identification of infection or the host response to infection is of crucial importance. The prediction of an individual marker or interleukin or its binding to surface proteins is not necessarily indicative for sepsis. In cases with unequivocally identified bacterial infections, the current results suggest that whole blood IL-8 may have a similar diagnostic accuracy as plasma levels. Of note, this technique needs less blood and is not being affected by hemolysis.