Assessment of urine CCL2 as a potential diagnostic biomarker for acute kidney injury and septic acute kidney injury in intensive care unit patients

Acute kidney injury (AKI) is a prevalent and serious condition in the intensive care unit (ICU), associated with significant morbidity and mortality. Septic acute kidney injury (SAKI) contributes substantially to AKI cases in the ICU. However, current diagnostic methods have limitations, necessitating the exploration of novel biomarkers. In this study, we investigated the potential of plasma and urine CCL2 levels as diagnostic markers for AKI and SAKI in 216 ICU patients. Our findings revealed significant differences in plasma (p < 0.01) and urine CCL2 (p < 0.0001) levels between AKI and non-AKI patients in the ICU. Notably, urine CCL2 demonstrated promising predictive value for AKI, exhibiting high specificity and sensitivity (AUC = 0.8976; p < 0.0001). Furthermore, we observed higher urine CCL2 levels in SAKI compared to non-septic AKI (p < 0.001) and urine CCL2 could also differentiate SAKI from non-septic AKI (AUC = 0.7597; p < 0.0001). These results suggest that urine CCL2 levels hold promise as early biomarkers for AKI and SAKI, offering valuable insights for timely intervention and improved management of ICU patients.

Transgenic human C-reactive protein affects oxidative stress but not inflammation biomarkers in the aorta of spontaneously hypertensive rats

BACKGROUND

C-reactive protein (CRP) is an acute inflammatory protein detected in obese patients with metabolic syndrome. Moreover, increased CRP levels have been linked with atherosclerotic disease, congestive heart failure, and ischemic heart disease, suggesting that it is not only a biomarker but also plays an active role in the pathophysiology of cardiovascular diseases. Since endothelial dysfunction plays an essential role in various cardiovascular pathologies and is characterized by increased expression of cell adhesion molecules and inflammatory markers, we aimed to detect specific markers of endothelial dysfunction, inflammation, and oxidative stress in spontaneously hypertensive rats (SHR) expressing human CRP. This model is genetically predisposed to the development of the metabolic syndrome.

METHODS

Transgenic SHR male rats (SHR-CRP) and non-transgenic SHR (SHR) at the age of 8 months were used. Metabolic profile (including serum and tissue triglyceride (TAG), serum insulin concentrations, insulin-stimulated incorporation of glucose, and serum non-esterified fatty acids (NEFA) levels) was measured. In addition, human serum CRP, MCP-1 (monocyte chemoattractant protein-1), and adiponectin were evaluated by means of ELISA, histological analysis was used to study morphological changes in the aorta, and western blot analysis of aortic tissue was performed to detect expression of endothelial, inflammatory, and oxidative stress markers.

RESULTS

The presence of human CRP was associated with significantly decreased insulin-stimulated glycogenesis in skeletal muscle, increased muscle and hepatic accumulation of TAG and decreased plasmatic cGMP concentrations, reduced adiponectin levels, and increased monocyte chemoattractant protein-1 (MCP-1) levels in the blood, suggesting pro-inflammatory and presence of multiple features of metabolic syndrome in SHR-CRP animals. Histological analysis of aortic sections did not reveal any visible morphological changes in animals from both SHR and SHR-CRP rats. Western blot analysis of the expression of proteins related to the proper function of endothelium demonstrated significant differences in the expression of p-eNOS/eNOS in the aorta, although endoglin (ENG) protein expression remained unaffected. In addition, the presence of human CRP in SHR in this study did not affect the expression of inflammatory markers, namely p-NFkB, P-selectin, and COX2 in the aorta. On the other hand, biomarkers related to oxidative stress, such as HO-1 and SOD3, were significantly changed, indicating the induction of oxidative stress.

CONCLUSIONS

Our findings demonstrate that CRP alone cannot fully induce the expression of endothelial dysfunction biomarkers, suggesting other risk factors of cardiovascular disorders are necessary to be involved to induce endothelial dysfunction with CRP.

IFI35 limits antitumor immunity in triple-negative breast cancer via CCL2 secretion

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with poor prognosis due to the lack of therapeutic targets. Although immunotherapy brings survival benefits to patients diagnosed with TNBC, it remains limited and treatment resistance is widespread. Here we demonstrate that IFI35 is highly expressed in tumor tissues and can be induced by Interferon-γ in a time-dependent and concentration-dependent manner in breast cancer cells. In xenograft models, we reveal that IFI35 dramatically increases myeloid-derived suppressor cells infiltration in tumors, along with depletion and anergy of CD8+T cells. IFI35 ablation leads to prolonged survival of the mice. Mechanistically, RNA-sequencing reveals that IFI35 promotes CCL2 secretion, resulting in the remodeling of TNBC immune microenvironment. Ablation of IFI35 promotes the infiltration of effector CD8+T cells, and thereby sensitizes TNBC to anti-PD-1 immunotherapy. Our data suggest that IFI35 limits antitumor immunity and may be expected to become a new immunotherapy target in TNBC.

Dimethyl malonate protects the lung in a murine model of acute respiratory distress syndrome

BACKGROUND

Succinate is a proinflammatory citric acid cycle metabolite that accumulates in tissues during pathophysiological states. Oxidation of succinate after ischemia-reperfusion leads to reversal of the electron transport chain and generation of reactive oxygen species. Dimethyl malonate (DMM) is a competitive inhibitor of succinate dehydrogenase, which has been shown to reduce succinate accumulation. We hypothesized that DMM would protect against inflammation in a murine model of ARDS.

METHODS

C57BL/6 mice were given ARDS via 67.7 μg of intratracheally administered lipopolysaccharide. Dimethyl malonate (50 mg/kg) was administered via tail vein injection 30 minutes after injury, then daily for 3 days. The animals were sacrificed on day 4 after bronchoalveolar lavage (BAL). Bronchoalveolar lavage cell counts were performed to examine cellular influx. Supernatant protein was quantified via Bradford protein assay. Animals receiving DMM (n = 8) were compared with those receiving sham injection (n = 8). Cells were fixed and stained with FITC-labeled wheat germ agglutinin to quantify the endothelial glycocalyx (EGX).

RESULTS

Total cell counts in BAL was less for animals receiving DMM (6.93 × 10 6 vs. 2.46 × 10 6 , p = 0.04). The DMM group had less BAL macrophages (168.6 vs. 85.1, p = 0.04) and lymphocytes (527.7 vs. 248.3; p = 0.04). Dimethyl malonate-treated animals had less protein leak in BAL than sham treated (1.48 vs. 1.15 μg/μl, p = 0.03). Treatment with DMM resulted in greater staining intensity of the EGX in the lung when compared with sham (12,016 vs. 15,186 arbitrary units, p = 0.03). Untreated animals had a greater degree of weight loss than treated animals (3.7% vs. 1.1%, p = 0.04). Dimethyl malonate prevented the upregulation of monocyte chemoattractant protein-1 (1.66 vs. 0.92 RE, p = 0.02) and ICAM-1 (1.40 vs. 1.01 RE, p = 0.05).

CONCLUSION

Dimethyl malonate reduces lung inflammation and capillary leak in ARDS. This may be mediated by protection of the EGX and inhibition of monocyte chemoattractant protein-1 and ICAM-1. Dimethyl malonate may be a novel therapeutic for ARDS.

Identification of effective CCR2 inhibitors for cancer therapy using humanized mice

C-C chemokine receptor type 2 (CCR2) is the receptor for C-C motif chemokine 2 (CCL2) and is associated with various inflammatory diseases and cancer metastasis. Although many inhibitors for CCR2 have been developed, it remains unresolved which inhibitors are the most effective in the clinical setting. In the present study, we compared 10 existing human CCR2 antagonists in a calcium influx assay using human monocytic leukemia cells. Among them, MK0812 was found to be the most potent inhibitor of human CCR2. Furthermore, we generated a human CCR2B knock-in mouse model to test the efficacy of MK0812 against a lung metastasis model of breast cancer. Oral administration of MK0812 to humanized mice did indeed reduce the number of monocytic myeloid-derived suppressor cells and the rate of lung metastasis. These results suggest that MK0812 is the most promising candidate among the commercially available CCR2 inhibitors. We propose that combining these two screening methods may provide an excellent experimental method for identifying effective drugs that inhibit human CCR2.

Antimicrobial peptides and other potential biomarkers of critical illness in SARS-CoV-2 patients with acute kidney injury. AMPAKI-CoV study

Antimicrobial peptides (AMPs) constitute a complex network of 10-100 amino acid sequence molecules widely distributed in nature. While over 300 AMPs have been described in mammals, cathelicidins and defensins remain the most extensively studied. Some publications have explored the role of AMPs in COVID-19, but these findings are preliminary, and in vivo studies are still lacking. In this study, we report the plasma levels of five AMPs (LL-37, α-defensin 1, α-defensin 3, β-defensin 1, and β-defensin 3), using the ELISA technique (MyBioSource, San Diego, CA, United States, kits MBS2601339 (beta-defensin 1), MBS2602513 (beta-defensin 3), MBS703879 (alpha-defensin 1), MBS706289 (alpha-defensin 3), MBS7234921 (LL37)), and the measurement of six cytokines (tumor necrosis factor-α, interleukin-1β, interleukin-6, interleukin-10, interferon-γ, and monocyte chemoattractant protein-1), through the magnetic bead immunoassay Milliplex® and the MAGPIX® System (MilliporeSigma, Darmstadt, Germany, kit HCYTOMAG-60 K (cytokines)), in 15 healthy volunteers, 36 COVID-19 patients without Acute Kidney Injury (AKI) and 17 COVID-19 patients with AKI. We found increased levels of α-defensin 1, α-defensin 3 and β-defensin 3, in our COVID-19 population, when compared to healthy controls, along with higher levels of interleukin-6, interleukin-10, interferon-γ, and monocyte chemoattractant protein-1. These findings suggest that these AMPs and cytokines may play a crucial role in the systemic inflammatory response and tissue damage characterizing severe COVID-19. The levels of α-defensin 1 and α-defensin 3 were significantly higher in COVID-19 AKI group in comparison to the non-AKI group. Furthermore, IL-10 and the product IL-10 × IL-1B showed excellent performance in discriminating AKI, with AUCs of 0.86 and 0.88, respectively. Among patients with COVID-19, AMPs may play a key role in the inflammation process and disease progression. Additionally, α-defensin 1 and α-defensin 3 may mediate the AKI process in these patients, representing an opportunity for further research and potential therapeutic alternatives in the future.

Effect of Sleeve Gastrectomy Versus One Anastomosis Gastric Bypass on Postoperative Renal Function and the Urinary Monocyte Chemoattractant Protein-1 (MCP-1) Level

INTRODUCTION

Bariatric surgery has been the most effective treatment modality for morbid obesity that reduces associated comorbidities and improves quality of life. This study aims at evaluating and comparing the impact of two types of bariatric surgery-laparoscopic sleeve gastrectomy (LSG) and one anastomosis gastric bypass (OAGB)-on renal functions and urinary monocyte chemoattractant protein-1 (MPC-1) levels in morbidly obese patients 3 months after surgery.

METHODS

This is a prospective study of 40 morbidly obese patients who underwent bariatric surgery. Two types of bariatric surgery were done-laparoscopic sleeve gastrectomy (LSG) (26 patients) and laparoscopic one anastomosis gastric bypass (OAGB) (14 patients). The outcomes of the two procedures were compared in terms of renal function parameters and the level of urinary MCP-1.

RESULTS

There were no statistically significant differences in the mean postoperative urinary MCP-1 (73.53 ± 21.25, 75.43 ± 26.17, P > 0.5), microalbuminuria (8.83 ± 6.26, 10.02 ± 8.6, P > 0.05), urinary creatinine (109.21 ± 43.22, 99.19 ± 48.65, P > 0.05), MCP1/Cr ratio (0.78 ± 0.36, 1.01 ± 0.70, P > 0.05), eGFR (100.32 ± 9.54, 104.39 ± 9.54, P > 0.05) in the cases who had either LSG operation or OAGB operation.

CONCLUSION

Bariatric surgery improves all indicators of kidney malfunction and reduces the level of urinary MCP-1. Both laparoscopic sleeve gastrectomy (LSG) and laparoscopic one anastomosis gastric bypass (OAGB) cause similar improvement of the renal function and reduction of urinary MCP-1 level.

Association Between Plasma Levels of Monocyte Chemoattractant Protein-1 (MCP-1) and 28-Day Mortality in Elderly Patients with Sepsis: A Retrospective Single-Center Study

BACKGROUND Previous studies have identified an association between plasma levels of the inflammatory cytokine, monocyte chemoattractant protein-1 (MCP-1), and outcomes for patients with sepsis. This retrospective single-center study assessed the association between plasma levels of MCP-1 and 28-day mortality in 136 patients ≥65 years diagnosed with sepsis between October 2020 and October 2021. MATERIAL AND METHODS The objective was to compare and analyze the parameters in the survival group (n=35) and the 28-day mortality group (n=101), including Sequential Organ Failure Assessment (SOFA), Acute Physiology and Chronic Health Evaluation II (APACHE II), plasma MCP-1, and laboratory test results. Plasma MCP-1 was quantified by cytokine test kit (LKTM014B, R&D). Statistical analysis was carried out in SPSS 26.0 and MedCalc 92.1.0 software. RESULTS The 28-day mortality group exhibited higher levels of SOFA, APACHEII, and plasma MCP-1 (all P<0.001), as well as lower levels of albumin, compared to the survival group (P<0.05). The logistic regression analysis findings indicated that SOFA, APACHEII, plasma MCP-1, and SBP are all independent risk factors for 28-day mortality. The area under the curve for SOFA, APACHEII, MCP-1, MCP-1+ SOFA, and MCP-1+APACHEII were 0.845, 0.744, 0.712, 0.879, and 0.822, respectively. MCP-1+SOFA exhibited higher sensitivity than SOFA alone. Furthermore, the assessment values of plasma MCP-1 combined with SOFA were superior to those of APACHE II or plasma MCP-1 (Z₁=2.661, Z₂=3.272, both P<0.01). CONCLUSIONS The findings from this study from a single center support those of previous studies that increased plasma levels of MCP-1 are significantly associated with 28-day mortality in patients with sepsis.

Pb induces the release of CXCL10 and CCL2 chemokines via mtROS/NF-κB activation in BV-2 cells

Lead (Pb), a well-known environmental pollutant, could cause damage of microglia, the resident macrophages vitally regulating inflammation in brain. Previous studies have found that Pb exposure induces typical pro-inflammatory factors release, such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), but what effects of Pb treatment below the dose causing these factors release are unknown. Thus, cytokines assay was performed to identify the factors released from Pb-treated BV-2 cells at 2.5 μM, causing no effects on TNF-α, IL-1β, and IL-6 release and cell death. Cytokines assay identified low doses of Pb exposure mainly induce an increase in specific chemokines, including CXCL10, CCL2, and CXCL2, which were confirmed by ELISA. Subsequent assessment found Pb could damage mitochondria function and generate mitochondrial reactive oxygen species (mtROS), and Mito TEMPO, a specific inhibitor of mtROS, suppressed Pb-caused upregulation of CXCL10 and CCL2, but not CXCL2. Finally, we determined that mtROS mediated Pb-induced activation of NF-κB pathway, as Mito TEMPO treatment inhibited P-p65/p65 escalation during Pb treatment. Inhibition of NF-κB pathway by Bay11-7821 suppressed the release of CXCL10 and CCL2. Collectively, low dose of Pb induces the release of CXCL10 and CCL2 chemokines, but not TNF-α and IL-1β, via mtROS/NF-κB activation in BV-2 cells.

Effect of specialized pro-resolving lipid mediators in the regulation of vascular tone and inflammation in human saphenous vein

Specialized pro-resolving lipid mediators (SPMs), derived from polyunsaturated fatty acids are important mediators in the resolution of inflammation. Recent studies have focused on the effects of SPMs in cardiovascular health and diseases. However, little is known about the effect SPMs on human vascular tone. Therefore, in this study it is aimed to investigate the effect of various SPMs including resolvin D- and E-series, maresin-1 (MaR1) and lipoxin-A4 (LxA4) on the vascular tone of human isolated saphenous vein (SV) preparations under inflammatory conditions. In addition, we aimed to evaluate the effects of SPMs on the release of pro-inflammatory mediators, monocyte chemoattractant protein-1 (MCP-1) and tumor necrosis factor-alpha (TNF- α) from human SV. Pretreatment of isolated of human SV with resolvin E1 (RvE1), resolvin D1 (RvD1) and MaR1 (100 nM, 18 h) significantly reduced the contractile responses to thromboxane A2 mimetic, U46619 whereas pretreatment with LxA4 and RvD2 (100 nM, 18 h) had no significant effect on the vascular tone of SV. Moreover, RvE1, RvD1 and MaR1 but not LxA4 and RvD2 (100 nM, 18 h) pretreatment diminished the release of MCP-1 and TNF-α from SV. In conclusion, our findings suggest that pre-treatment with RvE1, RvD1, and MaR1 could have potential benefits in decreasing graft vasospasm and vascular inflammation in SV.

C5a enhances Vδ1 T cells recruitment via the CCL2-CCR2 axis in IgA nephropathy

BACKGROUND

Mucosal immune-associated γδ T cells have been implicated in IgA nephropathy (IgAN). However, the involvement of Vδ1 T cells, the major γδ T cells subtype, in renal damage and the mechanism underlying their migration from peripheral blood to kidney in IgAN remain unclear.

METHODS

Clinical data from IgAN patients and healthy controls (HC) were analyzed. Phenotypes and chemokine receptors of γδ T cell were compared between IgAN patients and HC. Immunohistochemistry and immunofluorescence were performed to assess the infiltration of γδ T cell subsets and the expression of chemokine in renal tissues. In vitro, C5a was used to stimulate the human glomerular mesangial cells (HMCs) and chemotaxis experiment was used to examine Vδ1 T cells migration. Correlation between Vδ1 T cells and related clinical indicators were analyzed.

RESULTS

IgAN patients exhibited decreased Vδ1 T cell in blood but increased levels in kidneys compared to HC. Increased CCR2-expressing Vδ1 T cells and serum level of CCL2 were observed in IgAN patients. CCL2 co-localized with CCR2 in HMCs of IgAN. In vitro, C5a enhanced Vδ1 T cells recruitment by HMCs through CCL2-CCR2 axis. Importantly, circulating Vδ1 T cell levels showed a negatively correlated with both the urinary protein creatinine ratio (UACR) and 24-hour urine protein (UP). Moreover, kidney infiltration of Vδ1 cells positively correlated with UACR, UP, mesangial hyperplasia and renal tubule atrophy/interstitial fibrosis in IgAN.

CONCLUSIONS

C5a-induced production of CCL2 by HMCs facilitates Vδ1 T cells recruitment via the CCL2-CCR2 axis, contributing to renal damage in IgAN.

[Effect of ultrasonic curettage combined with sodium hyaluronate gel on chronic periodontitis and its effect on inflammatory factors hs-CRP, MCP-1 and MMP-13 in gingival crevicular fluid]

PURPOSE

To investigate the effect of ultrasonic curettage combined with sodium hyaluronate gel in the treatment of chronic periodontitis (CP) and the effect on inflammatory factor hypersensitive C-reactive protein (hs-CRP), monocyte chemotactic protein 1 (MCP-1) and matrix metalloproteinase 13 (MMP-13) in gingival crevicular fluid.

METHODS

A total of 102 patients with CP from October 2021 to October 2022 were selected, divided into experimental group (n=51) and control group (n=51) by random number table method. The control group received ultrasonic subgingival curetage, and the experimental group received sodium hyaluronate gel adjuvant therapy on the basis of the control group. The periodontal rehabilitation indexes, clinical efficacy and the changes of gingival crevicular fluid hs-CRP, MCP-1 and MMP-13 were compared between the two groups. The periodontal pathogens, bone metabolism indexes and the occurrence of adverse events during treatment were compared between the two groups. The data were statistically analyzed using SPSS 22.0 software package.

RESULTS

After treatment, the sulcus bleeding index (SBI), gingival index (GI), plaque index (PLI), periodontal pocket depth (PD) and attachment level (AL) of the two groups were significantly lower than before treatment (P＜0.05), and even significantly lower(P＜0.05) in the experimental group. Total effective rate of the experimental group was significantly higher than that of the control group(P＜0.05). hs-CRP, MCP-1 and MMP-13 in both groups after treatment were significantly lower than before treatment(P＜0.05), and hs-CRP, MCP-1 and MMP-13 in the experimental group after treatment were significantly lower than those in the control group(P＜0.05). The detection rates of Porphyromonas gingivalis, Forsetanella and Treponema dentalis were significantly lower in both groups after treatment than before treatment (P＜0.05), and the detection rates of the above indexes in the experimental group after treatment were significantly lower than those in the control group(P＜0.05). After treatment, the C-terminal peptide(CTX) of type Ⅰ collagen was significantly lower than that before treatment, and bone gla protein(BGP) was significantly higher than that before treatment(P＜0.05). The CTX and BGP of the experimental group were significantly lower than that of the control group and significantly higher than that of the control group(P＜0.05). There was no significant difference in the incidence of total adverse reactions between the two groups(P＞0.05). CONCLUSIONS：Ultrasonic curettage combined with sodium hyaluronate gel in the treatment of CP can promote periodontal tissue rehabilitation, enhance short-term efficacy, inhibit synthesis of inflammatory factors in gingival crevicular fluid, kill periodontal pathogens, regulate bone metabolism, and is safe and reliable.

CCL2, CCL8, CXCL12 chemokines in resectable non-small cell lung cancer (NSCLC)

BACKGROUND

Complex networks of chemokines are part of the immune reaction targeted against tumor cells. Chemokines influence cancer growth. It is unclear whether the concentrations of chemokines at the time of NSCLC (non-small cell lung cancer) diagnosis differ from healthy controls and reflect the extent of NSCLC.

AIMS

To compare chemokine concentrations (CCL2, CCL8, CXCL12) in the plasma of patients with resectable NSCLC to those without cancer. To determine whether the chemokine concentrations differ relative to the stage of disease.

METHODS

Sixty-nine patients undergoing surgery for proven/suspected NSCLC were enrolled. They underwent standard diagnostic and staging procedures to determine resectability, surgery was performed. Forty-two patients were diagnosed with NSCLC, while 27patients had benign lung lesions and functioned as the control group. Chemokine concentrations in peripheral blood were assessed using ELISA. Parametric statistics were used for the analysis of results.

RESULTS

There were no differences in plasma chemokine concentrations in NSCLC patients compared to controls. CXCL12 concentrations correlated positively with tumor extent expressed as clinical stage, (mean values: stage I 5.08 ng/mL, SEM 0.59; stage II and IIIA 7.82 ng/mL; SEM 1.06; P=0.022). Patients with NSCLC stages II+IIIA had significantly higher CXCL12 concentrations than controls (mean values: stage II+IIIA 7.82 ng/mL; SEM 1.06; controls 5.3 ng/mL; SEM 0.46; P=0.017).

CONCLUSION

CXCL12 was related to tumor growth and could potentially be used as a biomarker of advanced disease.

Anti-CCL2 antibody combined with etoposide prolongs survival in a minimal residual disease mouse model of neuroblastoma

C-C motif chemokine ligand 2 (CCL2) is a monocyte chemoattractant that promotes metastatic disease and portends a poor prognosis in many cancers. To determine the potential of anti-CCL2 inhibition as a therapy for recurrent metastatic disease in neuroblastoma, a mouse model of minimal residual disease was utilized in which residual disease was treated with anti-CCL2 monoclonal antibody with etoposide. The effect of anti-CCL2 antibody on neuroblastoma cells was determined in vitro with cell proliferation, transwell migration, and 2-dimensional chemotaxis migration assays. The in vivo efficacy of anti-CCL2 antibody and etoposide against neuroblastoma was assessed following resection of primary tumors formed by two cell lines or a patient-derived xenograft (PDX) in immunodeficient NOD-scid gamma mice. In vitro, anti-CCL2 antibody did not affect cell proliferation but significantly inhibited neuroblastoma cell and monocyte migration towards an increasing CCL2 concentration gradient. Treatment of mice with anti-CCL2 antibody combined with etoposide significantly increased survival of mice after resection of primary tumors, compared to untreated mice.

Intrarenal renin-angiotensin system activation and macrophage infiltrations in pediatric chronic glomerulonephritis

BACKGROUND

The current study tested the hypothesis that urinary angiotensinogen (UAGT) and urinary monocyte chemoattractant protein-1 (UMCP-1) levels provide a specific index of intrarenal renin-angiotensin system (RAS) status and the degree of infiltration of macrophages associated with RAS blockade and immunosuppressant treatment in pediatric patients with chronic glomerulonephritis.

METHODS

We measured baseline UAGT and UMCP-1 levels to examine the correlation between glomerular injury in 48 pediatric chronic glomerulonephritis patients before treatment. Furthermore, we performed immunohistochemical analysis of angiotensinogen (AGT) and CD68 in 27 pediatric chronic glomerulonephritis patients treated with RAS blockades and immunosuppressants for 2 years. Finally, we examined the effects of angiotensin II (Ang II) on monocyte chemoattractant protein-1 (MCP-1) expression in cultured human mesangial cells (MCs).

RESULTS

Baseline UAGT and UMCP-1 levels positively correlated with urinary protein levels, scores for mesangial hypercellularity, rate of crescentic formation, and expression levels of AGT and CD68 in renal tissues (p < 0.05). UAGT and UMCP-1 levels were significantly decreased after RAS blockade and immunosuppressant treatment (p < 0.01), which was accompanied by AGT and CD68 (p < 0.01), as well as the magnitude of glomerular injury. Cultured human MCs showed increased MCP-1 messenger ribonucleic acid and protein levels after Ang II treatment (p < 0.01).

CONCLUSIONS

The data indicates that UAGT and UMCP-1 are useful biomarkers of the degree of glomerular injury during RAS blockade and immunosuppressant treatment in pediatric patients with chronic glomerulonephritis.

Peripheral CCL2-CCR2 signalling contributes to chronic headache-related sensitization

Migraine, especially chronic migraine, is highly debilitating and still lacks effective treatment. The persistent headache arises from activation and sensitization of primary afferent neurons in the trigeminovascular pathway, but the underlying mechanisms remain incompletely understood. Animal studies indicate that signalling through chemokine C-C motif ligand 2 (CCL2) and C-C motif chemokine receptor 2 (CCR2) mediates the development of chronic pain after tissue or nerve injury. Some migraine patients had elevated CCL2 levels in CSF or cranial periosteum. However, whether the CCL2-CCR2 signalling pathway contributes to chronic migraine is not clear. Here, we modelled chronic headache with repeated administration of nitroglycerin (NTG, a reliable migraine trigger in migraineurs) and found that both Ccl2 and Ccr2 mRNA were upregulated in dura and trigeminal ganglion (TG) tissues that are implicated in migraine pathophysiology. In Ccl2 and Ccr2 global knockout mice, repeated NTG administration did not evoke acute or persistent facial skin hypersensitivity as in wild-type mice. Intraperitoneal injection of CCL2 neutralizing antibodies inhibited chronic headache-related behaviours induced by repeated NTG administration and repetitive restraint stress, suggesting that the peripheral CCL2-CCR2 signalling mediates headache chronification. We found that CCL2 was mainly expressed in TG neurons and cells associated with dura blood vessels, whereas CCR2 was expressed in subsets of macrophages and T cells in TG and dura but not in TG neurons under both control and disease states. Deletion of Ccr2 gene in primary afferent neurons did not alter NTG-induced sensitization, but eliminating CCR2 expression in either T cells or myeloid cells abolished NTG-induced behaviours, indicating that both CCL2-CCR2 signalling in T cells and macrophages are required to establish chronic headache-related sensitization. At cellular level, repeated NTG administration increased the number of TG neurons that responded to calcitonin-gene-related peptide (CGRP) and pituitary adenylate cyclase activating polypeptide (PACAP) as well as the production of CGRP in wild-type but not Ccr2 global knockout mice. Lastly, co-administration of CCL2 and CGRP neutralizing antibodies was more effective in reversing NTG-induced behaviours than individual antibodies. Taken together, these results suggest that migraine triggers activate CCL2-CCR2 signalling in macrophages and T cells. This consequently enhances both CGRP and PACAP signalling in TG neurons, ultimately leading to persistent neuronal sensitization underlying chronic headache. Our work not only identifies the peripheral CCL2 and CCR2 as potential targets for chronic migraine therapy, but also provides proof-of-concept that inhibition of both peripheral CGRP and CCL2-CCR2 signalling is more effective than targeting either pathway alone.

MCP-1/CCR2 axis is involved in the regulation of γδT cells in lupus nephritis

γδT cells are important innate immune cells that are involved in the occurrence and development of autoimmune diseases such as systemic lupus erythematosus (SLE). Lupus nephritis (LN) is a serious complication of SLE, characterized by the accumulation of immune cells (including γδT cells) in the target organs to participate in the disease process. Therefore, clarifying how γδT cells chemotactically migrate to target organs may be a key to developing therapeutic methods against LN. Enzyme-linked immunosorbent assay (ELISA) was used to detect serum levels of chemokines in LN patients and healthy controls. Real-time polymerase chain reaction (RT-PCR) and flow cytometry were used to measure the expression of chemokine receptors on the surface of γδT cells. The chemotactic migration ability of γδT cells was detected by Transwell assay. Signalling pathway activation of γδT cells was detected by Automated Capillary Electrophoresis Immunoassay and flow cytometry. The serum levels of chemokines, including monocyte chemoattractant protein-1 (MCP-1) in LN patients, were significantly increased. CCR2, the receptor of MCP-1, was also highly expressed on the surface of peripheral γδT cells in LN patients. In addition, the exogenous addition of MCP-1 can enhance chemotactic migration of γδT cells in LN patients. MCP-1 could activate STAT3 signalling in LN patients' peripheral γδT cells. γδT cells might participate in the pathogenesis of LN through MCP-1/CCR2 axis. This finding provides new opportunities for developing treatment methods against LN by targeting MCP-1/CCR2 axis.

Prediction of spontaneous preterm birth using CCL2 and CXCL10 in maternal serum of symptomatic high-risk pregnant women: a prospective cohort study

INTRODUCTION

CCL2 and CXCL10 are putative biomarkers for the prediction of spontaneous preterm birth. This study evaluates these markers in a cohort of pregnant high-risk women.

MATERIAL AND METHODS

In our prospective study, we included 109 women with signs of preterm labor between 20 + 0 and 31 + 6 weeks of gestation. Inclusion criteria were regular (< 3/30 min) or painful contractions, cervical length < 25 mm or a history of previous preterm birth (PTB). Blood samples were obtained upon first admission to our clinic. Biomarker concentrations were measured using pre-coated sandwich immunoassays (ELISA). Primary study outcome was spontaneous preterm birth < 34 weeks, secondary outcome was delivery < 37 weeks or within seven days after study inclusion.

RESULTS

Sixteen women (14.7%) delivered < 34 weeks and twenty women between 34 + 0 and 36 + 6 weeks (18.4%). Six patients (5.5%) gave birth within seven days after study admission. CXCL10 showed higher medium serum levels in women with PTB < 34 weeks (115 pg/ml compared to 61 pg/ml ≥ 34 weeks; p < 0.001) and < 37 weeks (103 pg/ml vs. 53 pg/ml; p < 0.001). In contrary, lower CCL2 serum levels were associated with PTB < 34 weeks (46 pg/ml vs. 73 pg/ml; p = 0.032) and birth within 7 days (25 pg/ml vs. 73 pg/ml; p = 0.008). The CXCL10/CCL2-ratio further improved the predictive model with a ROC-AUC of 0.83 (95% CI 0.73-0.93, p < 0.001) for delivery < 34 weeks. These corresponds to a sensitivity, specificity and positive predictive value of 0.67, 0.86 and 0.43 at a cut-off of 2.2.

CONCLUSION

Low maternal serum CCL2 levels are associated with a higher risk of preterm delivery within seven days. High CXCL10 serum levels are more associated with a high risk for preterm birth < 34 weeks. Elevated CXCL10/CCL2-ratio is showing the best predictive performance.

TRIAL REGISTRATION NUMBER (DRKS-ID)

DRKS00010763, Registration date: September 02, 2016.

Plasma levels of chemokines CCL2 and CXCL12 in female dogs with malignant mammary gland tumours without and with metastases

The aim of this study was to evaluate the plasma levels of chemokines CCL2 and CXCL12 in female dogs with malignant mammary gland tumours without and with metastases. The concentrations of CCL2 and CXCL12 were determined in 25 female dogs with malignant mammary gland tumours (15 without metastases and 10 with metastases) and 10 healthy control animals using a specific canine ELISA assay. The mean plasma concentrations of CCL2 and CXCL12 were significantly higher (p<0.05) in the metastatic group compared to the control group. Moreover, the concentrations of these chemokines were markedly higher in the dogs with metastases than in those without metastases; however, a statistically significant difference was not found. The concentrations of both tested chemokines were numerically increased in the dogs with grade 2 and grade 3 carcinomas compared to the dogs with grade 1 carcinomas but the differences did not reach statistical significance. In conclusion, the results of our study demonstrate that plasma concentrations of chemokines CCL2 and CXCL12 are significantly increased in the dogs with metastatic malignant mammary gland tumours compared to the healthy dogs and show an upward trend compared to those without metastases. However, clarifying whether the increase of these chemokines is a cause or an effect of metastasis in female dogs with malignant mammary gland tumours as well as their potential role in metastatic process requires further research.

A CCL2+DPP4+ subset of mesenchymal stem cells expedites aberrant formation of creeping fat in humans

Creeping fat is a typical feature of Crohn's disease. It refers to the expansion of mesenteric adipose tissue around inflamed and fibrotic intestines and is associated with stricture formation and intestinal obstruction. In this study, we characterize creeping fat as pro-adipogenic and pro-fibrotic. Lipidomics analysis of Crohn's disease patients (sixteen males, six females) and healthy controls (five males, ten females) reveals abnormal lipid metabolism in creeping fat. Through scRNA-seq analysis on mesenteric adipose tissue from patients (five males, one female) and healthy controls (two females), we identify a CCL2+DPP4+ subset of mesenchymal stem cells that expands in creeping fat and expedites adipogenic differentiation into dystrophic adipocytes in response to CCL20+CD14+ monocytes and IL-6, leading to the formation of creeping fat. Ex vivo experiments (tissues from five males, one female) confirm that both CCL20+CD14+ monocytes and IL-6 activate DPP4+ mesenchymal stem cells towards a pro-adipogenic phenotype. This study provides a comprehensive investigation of creeping fat formation and offers a conceptual framework for discovering therapeutic targets for treatment of Crohn's disease.

Role of Autologous Fat Transplantation Combined with Negative-Pressure Wound Therapy in Treating Rat Diabetic Wounds

BACKGROUND

Negative-pressure wound therapy (NPWT) and autologous fat transplantation (AFT) are two clinical modalities for plastic and reconstructive surgery. At present, there are few reports on the combination of these two methods in treating diabetic wounds. This study aimed to explore the effect of this combined therapy on diabetic wound healing.

METHODS

Full-thickness dorsal cutaneous wounds in rats with streptozotocin-induced diabetes were treated with either NPWT, AFT, or combined therapy. Rats covered with commercial dressings served as the control group. Macroscopic healing kinetics were examined. The levels of inflammation-related factors, such as interleukin-1β (IL-1β), interleukin-6 (IL-6), monocyte chemoattractant protein-1, arginase-1, and inducible nitric oxide synthase (iNOS) and angiogenesis-related factors such as vascular endothelial growth factor, were measured in the wound tissues on days 3, 7, and 14; immunohistochemical staining for arginase-1, iNOS, and CD31 was performed on days 3, 7, and 14. The length of reepithelialization was investigated on day 14.

RESULTS

The combined therapy promoted faster wound healing than the other treatments. The expression levels of the proinflammatory factors IL-1β, IL-6, monocyte chemoattractant protein-1 (MCP-1), and iNOS were reduced, and arginase-1 expression was increased compared with those in the other groups. The expression levels of vascular endothelial growth factor and CD31 in the NPWT-combined-with-AFT group were significantly higher than those in the other groups. Reepithelialization was faster in the NPWT-combined-with-AFT group (by day 14) than in the other groups.

CONCLUSION

Combining NPWT and AFT can enhance diabetic wound healing by improving wound inflammation and increasing wound vascularization.

CLINICAL RELEVANCE STATEMENT

The authors designed a randomized controlled trial of diabetic rats to confirm that NPWT can enhance the vascularization and improve inflammation of the diabetic wound after the autologous fat transplantation treatment. This article may provide a new idea for treating diabetic wounds.

Low CCL2 and CXCL8 Production and High Prevalence of Allergies in Children with Microcephaly Due to Congenital Zika Syndrome

Congenital Zika Syndrome (CZS) is associated with an increased risk of microcephaly in affected children. This study investigated the peripheral dysregulation of immune mediators in children with microcephaly due to CZS. Gene expression quantified by qPCR in whole blood samples showed an increase in IFNγ and IL-13 transcripts in children affected with microcephaly compared to the control group. The microcephaly group exhibited significantly decreased CCL2 and CXCL8 levels in serum, quantified by CBA assay. An allergic profile questionnaire revealed a high prevalence of allergies in the microcephaly group. In accordance, elevated serum IgE level measured by the Proquantum Immunoassay was observed in children affected with microcephaly compared to the control group. Altogether, these findings show a persistent systemic inflammation in children with microcephaly due to CZS and suggest a possible impairment in leukocyte migration caused by low production of CCL2 and CXCL8, in addition to high levels of IgE associated with high prevalence of allergies. The dysregulation of inflammatory genes and chemokines underscores the importance of understanding the immunological characteristics of CZS. Further investigation into the long-term consequences of systemic inflammation in these children is crucial for developing appropriate therapeutic strategies and tailored vaccination protocols.

FGF19/FGFR4-mediated elevation of ETV4 facilitates hepatocellular carcinoma metastasis by upregulating PD-L1 and CCL2

BACKGROUND & AIMS

Metastasis remains the major reason for the high mortality of patients with hepatocellular carcinoma (HCC). This study was designed to investigate the role of E-twenty-six-specific sequence variant 4 (ETV4) in promoting HCC metastasis and to explore a new combination therapy strategy for ETV4-mediated HCC metastasis.

METHODS

PLC/PRF/5, MHCC97H, Hepa1-6, and H22 cells were used to establish orthotopic HCC models. Clodronate liposomes were used to clear macrophages in C57BL/6 mice. Gr-1 monoclonal antibody was used to clear myeloid-derived suppressor cells (MDSCs) in C57BL/6 mice. Flow cytometry and immunofluorescence were used to detect the changes of key immune cells in the tumour microenvironment.

RESULTS

ETV4 expression was positively related to higher tumour-node-metastasis (TNM) stage, poor tumour differentiation, microvascular invasion, and poor prognosis in human HCC. Overexpression of ETV4 in HCC cells transactivated PD-L1 and CCL2 expression, which increased tumour-associated macrophage (TAM) and MDSC infiltration and inhibited CD8+ T-cell accumulation. Knockdown of CCL2 by lentivirus or CCR2 inhibitor CCX872 treatment impaired ETV4-induced TAM and MDSC infiltration and HCC metastasis. Furthermore, FGF19/FGFR4 and HGF/c-MET jointly upregulated ETV4 expression through the ERK1/2 pathway. Additionally, ETV4 upregulated FGFR4 expression, and downregulation of FGFR4 decreased ETV4-enhanced HCC metastasis, which created a FGF19-ETV4-FGFR4 positive feedback loop. Finally, anti-PD-L1 combined with FGFR4 inhibitor BLU-554 or MAPK inhibitor trametinib prominently inhibited FGF19-ETV4 signalling-induced HCC metastasis.

CONCLUSIONS

ETV4 is a prognostic biomarker, and anti-PD-L1 combined with FGFR4 inhibitor BLU-554 or MAPK inhibitor trametinib may be effective strategies to inhibit HCC metastasis.

IMPACT AND IMPLICATIONS

Here, we reported that ETV4 increased PD-L1 and chemokine CCL2 expression in HCC cells, which resulted in TAM and MDSC accumulation and CD8+ T-cell inhibition to facilitate HCC metastasis. More importantly, we found that anti-PD-L1 combined with FGFR4 inhibitor BLU-554 or MAPK inhibitor trametinib markedly inhibited FGF19-ETV4 signalling-mediated HCC metastasis. This preclinical study will provide a theoretical basis for the development of new combination immunotherapy strategies for patients with HCC.

The usability of MCP-1, fetuin-A, TAS, and TOS levels in the diagnosis of acute myocardial infarction

OBJECTIVE

Our aims were to determine whether the levels of plasma monocyte chemotactic protein-1 (MCP-1), fetuin-A, serum total antioxidant status (TAS), and serum total oxidant status (TOS) are cardiac biomarkers and to clarify their relationship with each other in acute myocardial infarction (AMI).

PATIENTS AND METHODS

The study included 90 participants: 60 patients with AMI [30 with and 30 without ST-segment elevation myocardial infarction (STEMI)] and 30 cardiac patients without AMI. The diagnostic values of serum Hs-cTnT, MCP-1, fetuin-A, TAS, and TOS levels in predicting AMI were evaluated statistically.

RESULTS

Median levels of MCP-1 [120.10 ng/L (interquartile range: 76.94-230.54 ng/L)] and TOS [2.89 U/MI (IQR: 2.31-3.94 U/Ml)] were statistically higher, and median levels of fetuin-A [433.52 mg/L (IQR: 387.89-584.49 mg/L)] and TAS (3.10 ± 0.86 U/mL) were lower in patients with AMI than in controls. The parameter with the area under the curve (0.815), sensitivity (73.3%), and specificity (66.7%) closest to those of Hs-cTnT was fetuin-A, followed by MCP-1, TOS, and TAS, respectively. A one-unit increase in MCP-1 levels increased the probability of AMI by 1.023 times (p = 0.002). A one-unit increase in fetuin-A levels decreased the probability of AMI by 0.995 times (p = 0.003). A one-unit increase in serum TOS levels was 1.29 times more characteristic of STEMI than of NSTEMI (p = 0.044).

CONCLUSIONS

MCP-1, oxidative stress parameters, and fetuin-A might support Hs-cTnT levels in the early diagnosis of AMI. Fetuin-A and MCP-1 levels may be independent risk factors for AMI, whereas TOS could be used to distinguish STEMI from NSTEMI.

Geniposide prevents tumor growth by inhibiting colonic interleukin-1β and monocyte chemoattractant protein-1 via down-regulated expression of cyclooxygenase-2 and thymocyte selection-associated high mobility box proteins TOX/TOX2 in azoxymethane/dextran sulfate sodium-treated mice

Colon cancer was the second leading cause of cancer-related deaths in Japan in 2019. The effects of geniposide isolated from Gardenia jasminoides fructus (Rubiaceae) on the azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced growth of colon tumors and changes in interleukin (IL)-1 β, monocyte chemoattractant protein (MCP)-1, IL-10, and programmed cell death-1 (PD-1) levels in the colon were investigated. The intraperitoneal administration of AOM (10 mg/kg) on days 0 and 27 induced colorectal carcinogenesis. Free access to 1% (w/v) DSS drinking water was given to mice on days 7-15, 32-33, and 35-38. Geniposide (30 and 100 mg/kg) was orally administered on days 1-16, discontinued for 11 days (days 16 to 26), and then administered again on days 27-41. Colonic levels of cytokines, chemokine, and PD-1 were measured using by enzyme-linked immunosorbent assay (ELISA). Increases in colorectal tumor numbers and areas were significantly inhibited by geniposide. In addition, geniposide (100 mg/kg) reduced colonic levels of IL-1 β, MCP-1, PD-1 and IL-10 by 67.4, 57.2, 100%, and 100% respectively. Cyclooxygenase (COX)-2- and thymocyte selection high mobility group box proteins (TOX/TOX2)-positive cell numbers were significantly reduced by geniposide. Geniposide (30 and 100 mg/kg) decreased the phosphorylation of signal transducer and activator of transcription 3 (STAT3) expressions in immunohistochemical analysis by 64.2 and 98.2%, respectively. Thus, the inhibitory effects of geniposide on colon tumor growth may be associated with reductions in the colonic levels of IL-1 β, MCP-1, IL-10, and PD-1 via the down-regulated expression of COX-2 and TOX/TOX2 through the inhibition of Phospho-STAT3 expression (in vivo and in vitro).

Short-term high-salt consumption does not influence resting or exercising heart rate variability but increases MCP-1 concentration in healthy young adults

High salt consumption increases blood pressure (BP) and cardiovascular disease risk by altering autonomic function and increasing inflammation. However, it is unclear whether salt manipulation alters resting and exercising heart rate variability (HRV), a noninvasive measure of autonomic function, in healthy young adults. The purpose of this investigation was to determine whether short-term high-salt intake 1) alters HRV at rest, during exercise, or exercise recovery and 2) increases the circulating concentration of the inflammatory biomarker monocyte chemoattractant protein 1 (MCP-1). With the use of a randomized, placebo-controlled, crossover study, 20 participants (8 females; 24 ± 4 yr old, 110 ± 10/64 ± 8 mmHg) consumed salt (3,900 mg sodium) or placebo capsules for 10 days each separated by ≥2 wk. We assessed HRV during 10 min of baseline rest, 50 min of cycling (60% V̇o2peak), and recovery. We quantified HRV using the standard deviation of normal-to-normal RR intervals, the root mean square of successive differences (RMSSD), and additional time and frequency domain metrics of HRV. Plasma samples were collected to assess MCP-1 concentration. No main effect of high salt or condition × time interaction was observed for HRV metrics. However, acute exercise reduced HRV (e.g., RMSSD time: P < 0.001, condition: P = 0.877, interaction: P = 0.422). High salt elevated plasma MCP-1 (72.4 ± 12.5 vs. 78.14 ± 14.7 pg/mL; P = 0.010). Irrespective of condition, MCP-1 was moderately associated (P values < 0.05) with systolic (r = 0.32) and mean BP (r = 0.33). Short-term high-salt consumption does not affect HRV; however, it increases circulating MCP-1, which may influence BP in young adults.

Immune-interacting lymphatic endothelial subtype at capillary terminals drives lymphatic malformation

Oncogenic mutations in PIK3CA, encoding p110α-PI3K, are a common cause of venous and lymphatic malformations. Vessel type-specific disease pathogenesis is poorly understood, hampering development of efficient therapies. Here, we reveal a new immune-interacting subtype of Ptx3-positive dermal lymphatic capillary endothelial cells (iLECs) that recruit pro-lymphangiogenic macrophages to promote progressive lymphatic overgrowth. Mouse model of Pik3caH1047R-driven vascular malformations showed that proliferation was induced in both venous and lymphatic ECs but sustained selectively in LECs of advanced lesions. Single-cell transcriptomics identified the iLEC population, residing at lymphatic capillary terminals of normal vasculature, that was expanded in Pik3caH1047R mice. Expression of pro-inflammatory genes, including monocyte/macrophage chemokine Ccl2, in Pik3caH1047R-iLECs was associated with recruitment of VEGF-C-producing macrophages. Macrophage depletion, CCL2 blockade, or anti-inflammatory COX-2 inhibition limited Pik3caH1047R-driven lymphangiogenesis. Thus, targeting the paracrine crosstalk involving iLECs and macrophages provides a new therapeutic opportunity for lymphatic malformations. Identification of iLECs further indicates that peripheral lymphatic vessels not only respond to but also actively orchestrate inflammatory processes.

Global deletion of CCL2 has adverse impacts on recovery of skeletal muscle fiber size and function and is muscle specific

Timely and complete recovery of muscle mass and function following a bout of physical disuse are critical components of returning to normal activities of daily living and lifestyle. Proper cross talk between the muscle tissue and myeloid cells (e.g., macrophages) throughout the recovery period from disuse atrophy plays a significant role in the complete resolution of muscle size and function. Chemokine C-C motif ligand 2 (CCL2) has a critical function of recruiting macrophages during the early phase of muscle damage. However, the importance of CCL2 has not been defined in the context of disuse and recovery. Here, we utilized a mouse model of whole body CCL2 deletion (CCL2KO) and subjected them to a period of hindlimb unloading followed by reloading to investigate the importance of CCL2 on the regrowth of muscle following disuse atrophy using ex vivo muscle tests, immunohistochemistry, and fluorescence-activated cell sorting approaches. We show mice that lack CCL2 display an incomplete recovery of gastrocnemius muscle mass, myofiber cross-sectional area, and EDL muscle contractile characteristics during the recovery from disuse atrophy. The soleus and plantaris had limited impact as a result of CCL2 deficiency suggesting a muscle-specific effect. Mice that lack CCL2 have decreased skeletal muscle collagen turnover, which may be related to defects in muscle function and stiffness. In addition, we show that the recruitment of macrophages to gastrocnemius muscle was dramatically reduced in CCL2KO mice during the recovery from disuse atrophy, which likely precipitated poor recovery of muscle size and function and aberrant collagen remodeling.NEW & NOTEWORTHY We provide evidence that the whole body loss of CCL2 in mice has adverse impacts on whole body function and skeletal muscle-specific contractile characteristics and collagen content. These defects in muscle function worsened during the recovery from disuse atrophy and corresponded with decreased recovery of muscle mass. We conclude that the absence of CCL2 decreased recruitment of proinflammatory macrophages to the muscle during the regrowth phase following disuse atrophy resulting in impaired collagen remodeling events and full resolution of muscle morphology and function.

Thirty-five years since the discovery of chemotactic cytokines, interleukin-8 and MCAF: A historical overview

Inflammation is a host defense response to various invading stimuli, but an excessive and persistent inflammatory response can cause tissue injury, which can lead to irreversible organ damage and dysfunction. Excessive inflammatory responses are believed to link to most human diseases. A specific type of leukocyte infiltration into invaded tissues is required for inflammation. Historically, the underlying molecular mechanisms of this process during inflammation were an enigma, compromising research in the fields of inflammation, immunology, and pathology. However, the pioneering discovery of chemotactic cytokines (chemokines), monocyte-derived neutrophil chemotactic factor (MDNCF; interleukin [IL]-8, CXCL8) and monocyte chemotactic and activating factor (MCAF; monocyte chemotactic factor 1 [MCP-1], CCL2) in the late 1980s finally enabled us to address this issue. In this review, we provide a historical overview of chemokine research over the last 35 years.

Circulating VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ as biomarkers of cancer in cancer-associated anti-TIF1-γ antibody-positive dermatomyositis

OBJECTIVES

The objective of the current study was to detect plasma profiles of inflammatory cytokines for determining potential biomarkers indicating cancer presence among the anti-TIF1-γ antibody-positive dermatomyositis (DM) patients.

METHODS

Twenty-seven cancer-associated anti-TIF1-γ antibody-positive DM (Cancer TIF1-γ-DM) patients were compared with 20 anti-TIF1-γ antibody-positive DM patients without cancer (Non-cancer TIF1-γ-DM) and 10 healthy controls (HC). The plasma levels of 17 cytokines were determined using the Luminex 200 system. The ability of plasma VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ levels to distinguish the presence of cancer was evaluated through the area under the curve (AUC) analysis. Potential protein interactions of TIF1-γ and the five cytokines were analyzed using the STRING database.

RESULTS

VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ plasma levels were significantly higher in the Cancer TIF1-γ-DM group, especially those without any anticancer treatment, than those in the non-cancer TIF1-γ-DM and HC groups. Meanwhile, anti-TIF1-γ antibody and the five cytokines could distinguish cancer presence in anti-TIF1-γ antibody-positive DM patients. The STRING network indicated that TIF1-γ potentially interacted with the cytokines. Positive correlations of VEGF-A among CCL2, IL-6, and IFN-γ and between IFN-γ and IL-6 were observed in Cancer TIF1-γ-DM patients. VEGF-A, TNF-α, CCL2, and IL-6 were positively associated with muscle-associated enzymes among the Cancer TIF1-γ-DM patients.

CONCLUSION

The present study identified VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ as significant potential biomarkers indicating the presence of cancer and demonstrated a more detailed cytokine profile during diagnosis. These biomarkers could provide better screening strategies and insight into the Cancer TIF1-γ-DM pathogenesis. Key Points • VEGF-A, TNF-α, CCL2, IL-6, and IFN-γ are potential biomarkers of cancer in cancer-associated anti-TIF1-γ antibody-positive dermatomyositis. Potential pathogenic molecular mechanism of the cancer-associated anti-TIF1-γ antibody-positive dermatomyositis.

Peripheral Inflammatory Markers TNF-α and CCL2 Revisited: Association with Parkinson's Disease Severity

One of the major mediators of neuroinflammation in PD is tumour necrosis factor alpha (TNF-α), which, similar to other cytokines, is produced by activated microglia and astrocytes. Although TNF-α can be neuroprotective in the brain, long-term neuroinflammation and TNF release can be harmful, having a neurotoxic role that leads to death of oligodendrocytes, astrocytes, and neurons and, therefore, is associated with neurodegeneration. Apart from cytokines, a wide family of molecules with homologous structures, namely chemokines, play a key role in neuro-inflammation by drawing cytotoxic T-lymphocytes and activating microglia. The objective of the current study was to examine the levels of the serum TNF-α and CCL2 (Chemokine (C-C motif) ligand 2), also known as MCP-1 (Monocyte Chemoattractant Protein-1), in PD patients compared with healthy controls. We also investigated the associations between the serum levels of these two inflammatory mediators and a number of clinical symptoms, in particular, disease severity and cognition. Such an assessment may point to their prognostic value and provide some treatment hints. PD patients with advanced stage on the Hoehn-Yahr scale showed an increase in TNF-α levels compared with PD patients with stages 1 and 2 (p = 0.01). Additionally, the UPDRS score was significantly associated with TNF-α levels. CCL2 levels, however, showed no significant associations.

Relationship between biomarkers of tubular injury and intrarenal hemodynamic dysfunction in youth with type 1 diabetes

BACKGROUND

Early identification of youth with type 1 diabetes (T1D) at risk for diabetic kidney disease may improve clinical outcomes. We examined the cross-sectional relationship between kidney biomarkers neutrophil gelatinase-associated lipocalin (NGAL), copeptin, interleukin-18 (IL-18), kidney injury molecule-1 (KIM-1), chitinase-3-like protein-1 (YKL-40), and monocyte chemoattractant protein-1 (MCP-1) and intrarenal hemodynamic function in adolescents with T1D.

METHODS

Urine albumin-to-creatinine ratio (UACR), renal vascular resistance (RVR), glomerular filtration rate (GFR), intraglomerular pressure (PGLO), efferent arteriole resistance (RE), afferent arteriolar resistance (RA), and renal plasma flow (RPF), and the above indicated biomarkers were assessed in youth aged 12-21 years with and without T1D of < 10 years duration.

RESULTS

Fifty adolescents with T1D (16.1 ± 3.0 years, HbA1c 8.6 ± 1.2%) and 20 adolescents of comparable BMI without T1D (16.1 ± 2.9 years, HbA1c 5.2 ± 0.2%) were enrolled. Adolescents with T1D demonstrated significantly higher GFR, RPF, RE, and PGLO than controls (39%, 33%, 74%, and 29%, respectively, all p < 0.0001). Adolescents with T1D also exhibited significantly lower RVR and RA than controls (25% and 155%, respectively, both p < 0.0001). YKL-40 and KIM-1 concentrations, respectively, were positively associated with GFR (r: 0.43, p = 0.002; r: 0.41, p = 0.003), RPF (r: 0.29, p = 0.08; r: 0.34, p = 0.04), UACR (r: 0.33, p = 0.02; r: 0.50, p = 0.0002), and PGLO (r: 0.45, p = 0.006; r: 0.52, p = 0.001) in adolescents with T1D.

CONCLUSIONS

Higher concentrations of biomarkers YKL-40 and KIM-1 may help define the risk for intraglomerular hemodynamic dysfunction in youth with T1D. A higher resolution version of the Graphical abstract is available as Supplementary information.

Ethnic differences in urinary monocyte chemoattractant protein-1 and heparanase-1 levels in individuals with type 2 diabetes: the HELIUS study

INTRODUCTION

We aimed to investigate ethnic differences in two urinary inflammatory markers in participants with type 2 diabetes mellitus (T2DM).

RESEARCH DESIGN AND METHODS

We included 55 Dutch, 127 South-Asian Surinamese, 92 African Surinamese, 62 Ghanaian, 74 Turkish and 88 Moroccan origin participants with T2DM from the HEalthy LIfe in an Urban Setting study. Using linear regression analyses, we investigated differences in urinary monocyte chemoattractant protein-1 (MCP-1) and heparanase-1 (HPSE-1) levels across ethnic minorities compared with Dutch. Associations between the urinary markers and albuminuria (albumin:creatinine ratio (ACR)) was investigated per ethnicity.

RESULTS

Urinary MCP-1 levels were higher in the Moroccan participants (0.15 log ng/mmol, 95% CI 0.05 to 0.26) compared with Dutch after multiple adjustments. Urinary HPSE-1 levels were lower in the African Surinamese and Ghanaian participants compared with the Dutch, with a difference of -0.16 log mU/mmol (95% CI -0.29 to -0.02) in African Surinamese and -0.16 log mU/mmol (95% CI -0.31 to -0.00) in Ghanaian after multiple adjustments. In all ethnic groups except the Dutch and Ghanaian participants, MCP-1 was associated with ACR. This association remained strongest after multiple adjustment in South-Asian and African Surinamese participants, with an increase in log ACR of 1.03% (95% CI 0.58 to 1.47) and 1.23% (95% CI 0.52 to 1.94) if log MCP-1 increased 1%. Only in the Dutch participants, an association between HPSE-1 and ACR was found, with increase in log ACR of 0.40% (95% CI 0.04 to 0.76) if log HPSE-1 increased 1%.

CONCLUSIONS

We found ethnic differences in urinary MCP-1 and HPSE-1 levels, in a multi-ethnic cohort of participants with T2DM. In addition, we found ethnic differences in the association of MCP-1 and HPSE-1 levels with albuminuria. These findings suggest differences in renal inflammation across ethnic groups.

Chemokine Profile in Psoriasis Patients in Correlation with Disease Severity and Pruritus

Psoriasis (PsO) is a chronic, immune-mediated, inflammatory skin disease associated in most cases with pruritus. Chemokines seem to play a significant role in PsO pathogenesis. The aim of the study was to analyse serum concentrations of CCL2/MCP-1, CCL3/MIP-1α, CCL4/MIP-1β, CCL5/RANTES, CCL17/TARC, CCL18/PARC, CCL22/MDC and CXCL8/IL-8, and their correlation with PsO severity and pruritus intensity. The study included 60 PsO patients and 40 healthy volunteers. Serum concentrations of six (CCL2/MCP-1, CCL3/MIP-1α, CCL5/RANTES, CCL17/TARC, CCL18/PARC and CCL22/MDC) out of eight analysed chemokines were significantly elevated in PsO patients; however, they did not correlate with disease severity. The serum level of CCL5/RANTES was significantly higher in patients with the psoriasis area and severity index (PASI) ≥ 15 (p = 0.01). The serum concentration of CCL17/TARC correlated positively with pruritus assessed using the visual analogue scale (VAS) (R = 0.47; p = 0.05). The study indicated CCL17/TARC as a potential biomarker of pruritus intensity in PsO patients. Chemokines appear to be involved in the development of PsO systemic inflammation. Further detailed studies on the interactions between chemokines, proinflammatory cytokines and immune system cells in PsO are required to search for new targeted therapies.

Severe acute pancreatitis exhibits distinct cytokine signatures and trajectories in humans: a prospective observational study

Severe acute pancreatitis (SAP) is associated with substantial morbidity and mortality. Several cytokines have been identified to have pathophysiological significance in SAP, but studies characterizing their early trajectories are lacking. Here we characterize the early trajectories of seven key cytokines associated with SAP and compare them with non-SAP subjects. Five proinflammatory cytokines (angiopoietin-2, interleukin-6, interleukin-8, monocyte chemoattractant protein-1, resistin) and two anti-inflammatory cytokines (hepatocyte growth factor, and soluble tumor necrosis factor-α receptor-1A) were measured in a prospective cohort of acute pancreatitis subjects (2012-2016) at the time of enrollment and then every 24 h for 5 days or until discharge. The cytokines' levels and trajectories were calibrated based on date of pain onset and were compared between healthy controls and three severity categories (mild, moderate, and severe). The cohort (n = 170) consisted of 27 healthy controls, 65 mild, 38 moderate, and 40 SAP. From day 1 of symptom onset, SAP subjects exhibited significantly higher levels of both pro- and anti-inflammatory cytokines compared with non-SAP and healthy subjects. But in SAP subjects, all proinflammatory cytokines' levels trended downward after day 2 (except for a flat slope for angiopoeitin-2) whereas for non-SAP subjects, the trajectory was upward: this trajectory difference between SAP versus non-SAP subjects resulted in narrowing of the differences initially seen on day 1 for proinflammatory cytokines. For anti-inflammatory cytokines, the trajectories were uniformly upward for both SAP and non-SAP subjects. Proinflammatory cytokine response is an early and time-sensitive event in SAP that should be accounted for when designing future biomarker studies and/or therapeutic trials.NEW & NOTEWORTHY In this study, we showed that the proinflammatory cytokine response in SAP is an early event, with subsequent downregulation of proinflammatory cytokines beginning at day 1 of symptom onset. Our findings underscore the importance of enrolling subjects very early in the disease course when conducting studies to investigate early immune events of SAP; this current study also serves as an important reference for the design of future biomarker studies and therapeutic trials in SAP.

Immunologic effects of red blood cell and platelet transfusions in neonates

PURPOSE OF REVIEW

Premature neonates are frequently transfused red blood cells (RBCs) or platelets to raise hemoglobin or platelet counts. However, these transfusions may have unintended effects on the immune system. This review will summarize the newest discoveries on the immunologic effects of RBC and platelet transfusions in neonates, and their potential impact on neonatal outcomes.

RECENT FINDINGS

Neonatal RBC transfusions are associated with increases in plasma pro-inflammatory cytokines, but recent findings suggest sex-specific differential responses. At least one cytokine (monocyte chemoattractant protein-1) rises in females receiving RBC transfusions, but not in males. These inflammatory responses correlate with poorer neurodevelopmental outcomes in heavily transfused female infants, while preterm male infants seem to be more sensitive to severe anemia. Platelet transfusions in preterm neonates are associated with increased neonatal mortality and morbidity. The underlying mechanisms are unknown, but likely related to the immune/inflammatory effects of transfused platelets. Adult platelets are different from neonatal platelets, with the potential to be more pro-inflammatory. Early preclinical data suggest that platelet transfusions alter the neonatal systemic inflammatory response and enhance immune cell migration.

SUMMARY

RBC and platelet transfusions alter neonatal immune and inflammatory responses. Their pro-inflammatory effects might worsen neonatal disease or affect neurodevelopmental outcomes.

Plasma Cytokine Profiles in Patients With Polypoidal Choroidal Vasculopathy and Neovascular Age-Related Macular Degeneration

PURPOSE

The concentrations of cytokines in plasma may be different between neovascular age-related macular degeneration (nAMD) and polypoidal choroidal vasculopathy (PCV). We studied plasma levels of cytokines in patients with nAMD and PCV and compared them with control individuals.

METHODS

This was a prospective, clinic-based, case-control study of treatment-naive participants (n=49) with PCV (n=24), nAMD (n=11), and cataract controls (n=14). We sampled fresh venous blood and isolated plasma for analysis. Plasma concentrations of 34 angiogenic and inflammatory cytokines were determined by Luminex bead-based multiplex array.

RESULTS

After adjusting for gender and age using multivariate logistic analysis, we found that the plasma concentrations of monocyte chemoattractant protein-1, vascular endothelial growth factor (VEGF)-A, and VEGF-D significantly higher in both nAMD and PCV patients than those in controls (all P<0.05, times in nAMD: 3.5, 4.3, and 13.8, respectively, times in PCV: 4.1, 4.0, and 11.5, respectively). In contrast, the plasma concentration of platelet-derived growth factor-BB was significantly lower in nAMD and PCV patients than those in controls (all P<0.05, times in nAMD: 1.6, times in PCV: 1.7). The plasma levels of leukemia inhibitory factor in nAMD group were significantly higher compared with PCV group (P<0.0167).

CONCLUSIONS

Multiple cytokines involved in systemic inflammation and angiogenesis including monocyte chemoattractant protein-1, platelet-derived growth factor-BB, VEGF-A, and VEGF-D may contribute to the pathogenesis of nAMD and PCV. Measurement of leukemia inhibitory factor in the plasma may help differentiate nAMD from PCV. This finding suggests that the 2 disorders may have different molecular mechanisms, and additional longitudinal studies will be needed to determine whether these findings have clinical relevance to influence treatment algorithms or provide novel targets for medical therapy.

CCL2: a Chemokine Potentially Promoting Early Seeding of the Latent HIV Reservoir

HIV infects long-lived CD4 memory T cells, establishing a latent viral reservoir that necessitates lifelong antiretroviral therapy (ART). How this reservoir is formed so quickly after infection remains unclear. We now show the innate inflammatory response to HIV infection results in CCL2 chemokine release, leading to recruitment of cells expressing the CCR2 receptor, including a subset of central memory CD4 T cells. Supporting a role for the CCL2/CCR2 axis in rapid reservoir formation, we find (i) treatment of humanized mice with anti-CCL2 antibodies during early HIV infection decreases reservoir seeding and preserves CCR2/5+ cells and (ii) CCR2/5+ cells from the blood of HIV-infected individuals on long-term ART contain significantly more integrated provirus than CCR2/5-negative memory or naive cells. Together, these studies support a model where the host's innate inflammatory response to HIV infection, including CCL2 production, leads to the recruitment of CCR2/5+ central memory CD4 T cells to zones of virus-associated inflammation, likely contributing to rapid formation of the latent HIV reservoir. IMPORTANCE There are currently over 35 million people living with HIV worldwide, and we still have no vaccine or scalable cure. One of the difficulties with HIV is its ability to rapidly establish a viral reservoir in lymphoid tissues that allows it to elude antivirals and the immune system. Thus, it is important to understand how HIV accomplishes this so we can develop preventive strategies. Our current results show that an early inflammatory response to HIV infection includes production of the chemokine CCL2, which recruits a unique subset of CCR2/5+ CD4+ T cells that become infected and form a significant reservoir for latent infection. Furthermore, we show that blockade of CCL2 in humanized mice significantly reduces persistent HIV infection. This information is relevant to the development of therapeutics to prevent and/or treat chronic HIV infections.

Inhibition of LPS-Induced Microglial Activation by the Ethyl Acetate Extract of Pueraria mirifica

Microglial activation has been found to play a crucial role in various neurological disorders. Proinflammatory substances overproduced by activated microglia, such as cytokines, chemokines, reactive oxygen species, and nitric oxide (NO), can result in neuroinflammation that further exacerbates the course of the diseases. This study aimed to explore the anti-inflammatory effect of the ethyl acetate extract of Pueraria mirifica on microglial activation. Lipopolysaccharide (LPS)-induced inflammation was used as a model to investigate the effects of P. mirifica on HAPI (highly aggressive proliferating immortalized), a rat microglial cell line. Administration of ethyl acetate extract from the tuberous roots of P. mirifica to HAPI cells dose-dependently reduced NO production and iNOS expression induced by LPS. Attenuation of IRF-1 (interferon regulatory factor-1) induction, one of the transcription factors governing iNOS expression, suggested that the inhibitory effect on NO production by the plant extract was at least partially mediated through this transcription factor. In addition, LPS-stimulated mRNA expression of MCP-1 (monocyte chemoattractant protein-1), IL-6 (interleukin-6), and TNF-α (tumor necrosis factor-α) was also suppressed with P. mirifica extract pretreatment. This study indicates that the ethyl acetate extract of P. mirifica could potentially serve as an anti-inflammatory mediator and may be useful in relieving the severity of neurological diseases where microglia play a role.

IL-4, IL-10, CCL2 and TGF-β as potential biomarkers for severity in Plasmodium vivax malaria

Cytokines and chemokines are immune response molecules that display diverse functions, such as inflammation and immune regulation. In Plasmodium vivax infections, the uncontrolled production of these molecules is thought to contribute to pathogenesis and has been proposed as a possible predictor for disease complications. The objective of this study was to evaluate the cytokine profile of P. vivax malaria patients with different clinical outcomes to identify possible immune biomarkers for severe P. vivax malaria. The study included patients with non-severe (n = 56), or severe (n = 50) P. vivax malaria and healthy controls (n = 50). Patient plasma concentrations of IL-4, IL-2, CXCL10, IL-1β, TNF-α, CCL2, IL-17A, IL-6, IL-10, IFN-γ, IL-12p70, CXCL8 and active TGF-β1 were determined through flow cytometry. The levels of several cytokines and chemokines, CXCL10, IL-10, IL-6, IL-4, CCL2 and IFN-γ were found to be significantly higher in severe, compared to non-severe P. vivax malaria patients. Severe thrombocytopenia was positively correlated with IL-4, CXCL10, IL-6, IL-10 and IFN-γ levels, renal dysfunction was related to an increase in IL-2, IL-1β, IL-17A and IL-8, and hepatic impairment with CXCL10, MCP-1, IL-6 and IFN-γ. A Lasso regression model suggests that IL-4, IL-10, CCL2 and TGF-β might be developed as biomarkers for severity in P. vivax malaria. Severe P. vivax malaria patients present specific cytokine and chemokine profiles that are different from non-severe patients and that could potentially be developed as biomarkers for disease severity.

Plasmodium vivax is one of the main species responsible for malaria in the world. The pathogenic mechanisms leading to the development of severe P. vivax malaria are not yet fully understood. Immune system molecules such as cytokines and chemokines actively participate in the control of the infection, however, their uncontrolled production can influence alterations in organs such as the liver, kidneys, among others. In this study we show that there is a differential concentration of some cytokines and chemokines between patients with non-severe malaria and severe P. vivax malaria; and that there are associations between these molecules with manifestations that occur in severe malaria. Four molecules with potential to become biomarkers of severity were identified.

Association of Blood MCP-1 Levels with Risk of Obstructive Sleep Apnea: A Systematic Review and Meta-Analysis

Background and objective: Among the broad variety of chemokines, monocyte chemoattractant protein-1 (MCP-1) is considered to be one of the most important chemokines. Among others, MCP-1 activates monocytes and other immune cells highly involved in inflammation. In the present systematic review and meta-analysis, we evaluated the relationship between serum/plasma MCP-1 levels and the risk of obstructive sleep apnea (OSA) in adults as a disease related to inflammation. Materials and methods: Four databases were systematically investigated until 12 July 2022. We used the Review Manager 5.3 software (Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, Copenhagen, Denmark) to extract and calculate the standardized mean difference (SMD) and its 95% confidence interval (CI) of plasma/serum levels of MCP-1 between adults with and without OSA. Results: Eight articles including eleven studies in adults were entered into the meta-analysis. The serum/plasma MCP-1 levels in adults with OSA were higher than that in the controls (SMD = 0.81; p = 0.0007) and as well as for adults with severe OSA compared to those with mild and moderate OSA (SMD = 0.42; p < 0.0001). The subgroup analysis showed that ethnicity was an effective factor in the pooled analysis of blood MCP-1 levels in adults with OSA compared to the controls (Asians: (p < 0.0001), mixed ethnicity: (p = 0.04), and Caucasians: (p = 0.89)). The meta-regression showed increasing serum/plasma MCP-1 levels in adults with OSA versus the controls, publication year, age of controls, body mass index (BMI) of controls, and sample size reduced, and also BMI and the apnea−hypopnea index of adults with OSA increased. Conclusions: The meta-analysis showed that compared to the controls, serum/plasma levels of MCP-1 in adults with OSA were significantly more, as well as adults with severe OSA having more serum/plasma MCP-1 levels compared to the adults with mild to moderate OSA. Therefore, MCP-1 can be used as a diagnostic and therapeutic factor in adults with OSA.

Analytical performance of a canine ELISA monocyte chemoattractant protein-1 assay for use in cats and evaluation of circulating levels in normal weight and obese cats

BACKGROUND

In human and murine obesity, adipose tissue dwelling macrophages and adipocytes produce monocyte chemoattractant protein-1 (MCP-1) leading to systemic low-grade inflammation. The aim of the study was to validate a canine MCP-1 ELISA assay for use in cats and to investigate whether a difference in MCP-1 concentrations could be detected between: a) cats having normal or elevated circulating serum amyloid A (SAA) levels and b) normal weight and obese cats. Serum obtained from 36 client-owned cats of various breed, age and sex with normal (n = 20) to elevated SAA (n = 16) was used for the validation of the canine MCP-1 ELISA assay. As no golden standard exists for measurement of inflammation, circulating MCP-1 concentrations were compared to SAA measurements, as an indicator of systemic inflammation. Analytical precision, dilution recovery and detection limit were calculated. A possible correlation between MCP-1 concentrations and obesity related measures (body fat percentage (BF%), insulin sensitivity and cytokine expression) were investigated in another population of 73 healthy, lean to obese, neutered domestic short-haired cats.

RESULTS

Intra- (2.7-4.1%) and inter-assay (2.2-3.6%) coefficient of variation and dilution recovery were acceptable, and the detection limit was 27.1 pg/mL. MCP-1 did not correlate with SAA, and there was no difference between the inflammatory (SAA > 20 mg/L) and non-inflammatory group, due to a marked overlap in MCP-1 concentrations. Circulating MCP-1 concentrations were unaffected by BF% (r2 = 2.7 × 10-6, P = 0.21) and other obesity-related markers.

CONCLUSIONS

The present canine ELISA assay seems to be able to measure circulating feline MCP-1. However, further studies are needed to determine its possible use for detecting inflammation in relation to disease processes or obesity-related low-grade inflammation in cats.

[Effects of bifid triple viable on chronic low-grade inflammation in obese mice induced by high fat diet]

OBJECTIVE

To explore the effects and possible mechanism of bifid triple viable(BTV) on chronic low-grade inflammation and insulin resistance in obese mice induced by high fat diet(DIO).

METHODS

A total of 18 male C57 BL/6 J mice aged 6 weeks were randomly divided into two groups according to their body weight after adaptive feeding for 2 weeks. Six mice in one group were fed with normal rodent diet as control group. Twelve mice in the other group were fed with high fat diet(60% kcal% fat)(HF). After 8 weeks, it was confirmed that body weight and fasting blood glucose of the mice fed with high fat diet were significantly higher than those of the control group(P&lt;0.001), and then they were randomly divided into HF group and HF+BTV group according to the body weight and fasting blood glucose. Six mice in the HF group continued to be fed with high fat diet. Six mice in the HF+BTV group were fed with high fat diet and administered bifid triple viable suspension by gavage(24 mg/kg body weight), once a day. Mice in the control group and HF group were given equal volume of water as control treatment. After 4 weeks of treatment, blood was collected from tail vein, and the fasting blood glucose was measured by automatic glucose meter. Then the animals were killed and collected blood, distal ileum, liver and epididymal white adipose tissue. The tight junctions between the epithelial cells of ileum mucosa were observed by transmission electron microscopy. Serum endotoxin(also called lipopolysaccharide, LPS) levels were determined by limulus amebocyte lysate assay. Immunohistochemical staining was used to observe the macrophage marker F4/80 in liver and epididymal white adipose tissue. Serum fasting insulin levels, tumor necrosis factor-α(TNF-α), interlukin-6(IL-6) and monocyte chemotactic protein-1(MCP-1) in liver and/or epididymal white adipose tissue were detected by ELISA. The index of homeostasis model assessment of insulin resistance(HOMA-IR) was calculated by formula.

RESULTS

Compared with the mice fed with normal rodents diet, the tight junctions between the epithelial cells of ileum mucosa were loose, the levels of serum endotoxin, live TNF-α and IL-6, epididymal white adipose tissue TNF-α, IL-6, MCP-1 were significantly elevated(P&lt;0.05), the number of macrophages increased in liver and epididymal white adipose tissue, fasting glucose, fasting insulin levels and HOMA-IR were significantly up-regulated(P&lt;0.01) in the HF group. In comparison with the HF group, the structures of tight junctions between the epithelial cells of ileum mucosa were normalized, the levels of serum endotoxin, liver TNF-α, IL-6 and epididymal white adipose tissue TNF-α, IL-6, MCP-1 were obviously decreased(P&lt;0.05), the number of macrophages reduced in liver and epididymal white adipocytes, fasting insulin levels and HOMA-IR were significantly down-regulated(P&lt;0.05), but had no effect on fasting blood glucose levels in HF+BTV group.

CONCLUSION

Bifid triple viable may protect intestinal mucosa barrier, alleviate metabolic endotoxemia, thus improve chronic low-grade inflammation in liver and adipose tissue, and partially restore insulin sensitivity in DIO mice by regulating gut microbiota.

Total glucosides of paeony inhibit breast cancer growth by inhibiting TAMs infiltration through NF-κB/CCL2 signaling

PURPOSE

The high density of tumor-associated macrophages (TAMs) and inflammatory factors are crucial elements leading to tumor immune tolerance. Previously, we found that total glucosides of paeony (TGP) have strong inhibitory effects on the release of various inflammatory factors; however, it is unclear whether the inhibitory effects can improve the inflammatory microenvironment of tumors. Therefore, in the present study, we investigated the mechanism via which TGP depresses tumor growth and metastasis via modulation of TAM infiltration in breast cancer.

METHODS

We assessed the effects of TGP on various mouse models of tumor. Lung metastasis was detected using hematoxylin and eosin staining. T cell (CD3⁺CD4⁺ and CD3⁺CD8⁺) effector and memory subsets, and TAM (CD45⁺CD11b⁺F4/80⁺) populations in the tumor microenvironment (TME) were examined using flow cytometry. Lipopolysaccharide (LPS)-stimulated macrophage experiments were used to investigate the TGP anti-inflammatory effects in vitro. Furthermore, conditional medium (CM) was added to detect 4T1 breast cancer cell growth using a Real-Time Cell Analyzer (RTCA) xCELLigence system. Inflammatory cytokine and chemokine levels were measured using cytometric bead array (CBA) kits and quantitative polymerase chain reaction (qPCR). NF-κB expression in the nucleus was examined by immunofluorescence and Western blot analysis.

RESULTS

TGP suppressed tumor growth and lung metastasis, decreased CD45⁺CD11b⁺F4/80⁺ (TAMs) population obviously, and increased CD44^LowCD62L^Hi (T memory stem cells) and CD44^HiCD62L^Hi (central memory cells) populations in the tumor-infiltrating CD4⁺ and CD8⁺ T cells. In addition, TGP reduced inflammatory factor levels in tumors, thus inhibiting the infiltration of TAMs to improve the inflammation immunosuppressive microenvironment. In the in vitro experiment, TGP inhibited IL-10 and C-C Motif Chemokine Ligand 2 (CCL2) secretion and mRNA expression in LPS-stimulated macrophages to inhibit 4T1 cell growth and restrain macrophages M2 polarization. In addition, TGP can directly inhibit 4T1 cell proliferation by restraining autocrine CCL2 and IL-10. Further mechanistic studies reavealed that TGP inhibited CCL2 secretion by inhibiting NF-κB accumulation in the nucleus in macrophages.

CONCLUSION

TGP reduced TAM recruitment mainly through the NF-κB/CCL2 signaling pathway, thereby promoting T cell infiltration in the TME. TGP has a unique advantage in balancing the inflammatory response. Furthermore, our results present novel insights on the mechanisms underlying TAM infiltration that were inhibited by TGP, with potential application in development of novel therapies targeting CCL2 pathways.

Evaluation of tuberculosis diagnostic biomarkers in immunocompromised hosts based on cytokine levels in QuantiFERON-TB Gold Plus

Tuberculosis (TB) remains a serious health concern globally. QuantiFERON-TB (QFT) is a diagnostic tool for TB detection, and its sensitivity is reduced in immunocompromised hosts with low T lymphocyte counts or abnormal T cell function. This study aimed to evaluate the correlation between T cell and cytokine levels in patients with active TB using QFT-Plus. Forty-five patients with active TB were enrolled, and the cytokines in QFT-Plus tube supernatants were quantified using the MAGPIX System. CD4⁺ T cell count negatively correlated with patient age (p < 0.001, r = -0.51). The levels of TB1-responsive interleukin-1 receptor antagonist (IL-1Ra) and IL-2 correlated with CD4⁺ T cell count, whereas the levels of TB2-responsive IL-1Ra and IFN-γ-induced protein 10 correlated with both CD4⁺ and CD8⁺ T cell counts. Cytokines that correlated with CD4⁺ and CD8⁺ T cell counts might not be suitable TB diagnostic biomarkers in immunocompromised hosts. Notably, cytokines that did not correlate with the T cell counts, such as monocyte chemoattractant protein-1, might be candidate biomarkers for TB in immunocompromised hosts. Our findings might help improve TB diagnosis, which could enable prompt treatment and minimize poor disease outcomes.

Effects of antifibrinolytics on systemic and cerebral inflammation after traumatic brain injury

BACKGROUND

Administration of antifibrinolytic medications, including tranexamic acid (TXA), may reduce head injury-related mortality. The effect of these medications on post-traumatic brain injury (TBI) inflammatory response is unknown. The goal of this study was to investigate the role of available antifibrinolytic medications on both systemic and cerebral inflammation after TBI.

METHODS

An established murine weight drop model was used to induce a moderate TBI. Mice were administered 1, 10, or 100 mg/kg of TXA, 400 mg/kg of aminocaproic acid (Amicar, Hospira, Lake Forest, IL), 100 kIU/kg of aprotonin, or equivalent volume of normal saline (NS) 10 minutes after recovery. Mice were euthanized at 1, 6, or 24 hours. Serum and cerebral tissue were analyzed for neuron-specific enolase and inflammatory cytokines. Hippocampal histology was evaluated at 30 days for phosphorylated tau accumulation.

RESULTS

One hour after TBI, mice given TXA displayed decreased cerebral cytokine concentrations of tumor necrosis factor α (TNF-α) and, by 24 hours, displayed decreased concentrations of cerebral TNF-α, interleukin (IL)-6, and monocyte chemoattractant protein 1 compared with TBI-NS. However, serum concentrations of TNF-α and macrophage inflammatory protein 1α (MIP-1α) were significantly elevated from 1 to 24 hours in TBI-TXA groups compared with TBI-NS. The concentration of phosphorylated tau was significantly decreased in a dose-dependent manner in TBI-TXA groups compared with TBI-NS. By contrast, Amicar administration increased cerebral cytokine levels of IL-6 1 hour after TBI, with serum elevations noted in TNF-α, MIP-1α, and monocyte chemoattractant protein 1 at 24 hours compared with TBI-NS. Aprotonin administration increased serum TNF-α, IL-6, and MIP-1α from 1 to 24 hours without differences in cerebral cytokines compared with TBI-NS.

CONCLUSION

Tranexamic acid administration may provide acute neuroinflammatory protection in a dose-dependent manner. Amicar administration may be detrimental after TBI with increased cerebral and systemic inflammatory effects. Aprotonin administration may increase systemic inflammation without significant contributions to neuroinflammation. While no antifibrinolytic medication improved systemic inflammation, these data suggest that TXA may provide the most beneficial inflammatory modulation after TBI.

Bindarit Reduces Bone Loss in Ovariectomized Mice by Inhibiting CCL2 and CCL7 Expression via the NF-κB Signaling Pathway

OBJECTIVE

To investigate the changes in proinflammatory cytokines and chemokines, namely, C-C motif ligand (CCL) 2 and CCL7, in postmenopausal osteoporosis (PMOP) and to develop a new drug, bindarit (Bnd), for PMOP in an ovariectomized (OVX) mouse model.

METHODS

Bone marrow macrophages (BMMs) from the femurs of five women with PMOP and five premenopausal women without osteoporosis were detected by RNA sequencing. BMMs from mice were differentiated into osteoclasts and treated with a synthetic inhibitor of CCL2 and CCL7, Bnd, or 17 beta estradiol (E2 ). Mouse BMMs were differentiated into osteoclasts with or without Bnd for 7 days and analyzed by RNA sequencing. Osteoblasts of mice were induced to undergo osteoblastogenesis and treated with Bnd. OVX mice were treated with E2 or Bnd after surgery. The protein and mRNA expression of CCL2 and CCL7 was detected using immunostaining and qPCR, respectively, in OVX and aged mice and in cells cultured in vitro. Osteoclast formation was detected using a tartrate-resistant acid phosphatase (TRAP) assay in vitro and in vivo. Alkaline phosphatase (ALP), runt-related transcription factor 2 (Runx2) and osteocalcin (OCN) were detected using immunostaining to evaluate osteogenesis. Microcomputed tomography was conducted to analyze trabecular bone parameters, the structure model index, bone mineral density and other variables. Nuclear factor-κB (NF-κB) signaling pathway-related protein phosphorylation of IKKα/β (p-IKKα/β) and p-NFκB p65 was examined using western blotting.

RESULTS

CCL2, CCL7 and their receptor of C-C chemokine receptor-2 (CCR2), and the NF-κB signaling pathway, were significantly increased in women with PMOP. CCL2 and CCL7 protein and mRNA expression was increased in OVX mice and aged female mice, but the increases were attenuated by E2 and Bnd. E2 and Bnd effectively inhibited osteoclastogenesis and the protein expression of CCL2 and CCL7 both in vitro and in vivo and reduced bone loss in OVX mice. Bnd did not affect the mineralization of osteoblasts directly in vitro but reduced bone turnover in vivo. p-IKKα/β and p-NFκB p65 levels were increased in BMMs of mice after differentiation into osteoclasts but were significantly decreased by Bnd.

CONCLUSION

The proinflammatory cytokines and chemokines CCL2, CCL7 and CCR2 were correlated with PMOP. Bnd attenuated the increases in CCL2 and CCL7 levels to affect osteoporosis in OVX mice via the NFκB signaling pathway. Thus, Bnd may be useful as a new therapeutic for the prevention of PMOP.

Significant Therapeutic Effects of Adult Human Neural Stem Cells for Spinal Cord Injury Are Mediated by Monocyte Chemoattractant Protein-1 (MCP-1)

The limited capability of regeneration in the human central nervous system leads to severe and permanent disabilities following spinal cord injury (SCI) while patients suffer from no viable treatment option. Adult human neural stem cells (ahNSCs) are unique cells derived from the adult human brain, which have the essential characteristics of NSCs. The objective of this study was to characterize the therapeutic effects of ahNSCs isolated from the temporal lobes of focal cortical dysplasia type IIIa for SCI and to elucidate their treatment mechanisms. Results showed that the recovery of motor functions was significantly improved in groups transplanted with ahNSCs, where, in damaged regions of spinal cords, the numbers of both spread and regenerated nerve fibers were observed to be higher than the vehicle group. In addition, the distance between neuronal nuclei in damaged spinal cord tissue was significantly closer in treatment groups than the vehicle group. Based on an immunohistochemistry analysis, those neuroprotective effects of ahNSCs in SCI were found to be mediated by inhibiting apoptosis of spinal cord neurons. Moreover, the analysis of the conditioned medium (CM) of ahNSCs revealed that such neuroprotective effects were mediated by paracrine effects with various types of cytokines released from ahNSCs, where monocyte chemoattractant protein-1 (MCP-1, also known as CCL2) was identified as a key paracrine mediator. These results of ahNSCs could be utilized further in the preclinical and clinical development of effective and safe cell therapeutics for SCI, with no available therapeutic options at present.

Reduced Electroencephalogram Complexity in Postoperative Delirium

Delirium is associated with electroencephalogram (EEG) slowing and impairments in connectivity. We hypothesized that delirium would be accompanied by a reduction in the available cortical information (ie, there is less information processing occurring), as measured by a surrogate, Lempil-Ziv Complexity (LZC), a measure of time-domain complexity. Two ongoing perioperative cohort studies (NCT03124303, NCT02926417) contributed EEG data from 91 patients before and after surgery; 89 participants were used in the analyses. After cleaning and filtering (0.1-50Hz), the perioperative change in LZC and LZC normalized (LZCn) to a phase-shuffled distribution were calculated. The primary outcome was the correlation of within-patient paired changes in delirium severity (Delirium Rating Scale-98 [DRS]) and LZC. Scalp-wide threshold-free cluster enhancement was employed for multiple comparison correction. LZC negatively correlated with DRS in a scalp-wide manner (peak channel r2 = .199, p < .001). This whole brain effect remained for LZCn, though the correlations were weaker (peak channel r2 = .076, p = .010). Delirium diagnosis was similarly associated with decreases in LZC (peak channel p < .001). For LZCn, the topological significance was constrained to the midline posterior regions (peak channel p = .006). We found a negative correlation of LZC in the posterior and temporal regions with monocyte chemoattractant protein-1 (peak channel r2 = .264, p < .001, n = 47) but not for LZCn. Complexity of the EEG signal fades proportionately to delirium severity implying reduced cortical information. Peripheral inflammation, as assessed by monocyte chemoattractant protein-1, does not entirely account for this effect, suggesting that additional pathogenic mechanisms are involved.

CCL2-mediated monocytes regulate immune checkpoint blockade resistance in pancreatic cancer

The immunosuppressive microenvironment of pancreatic ductal adenocarcinoma (PDAC) contributes to resistance to immune checkpoint blockade. C-C motif chemokine ligand 2 (CCL2) is believed to participate in pancreatic tumorigenesis, but its role in PDAC progression and resistance to immune checkpoint blockade remains unclear. We hypothesized that CCL2 contributes to the pancreatic immunosuppressive microenvironment. In this study, we found that CCL2 recruits monocytes to and decrease CD8⁺ T cell infiltration in pancreatic tumors. CCL2 inhibition and monocyte neutralization increased the sensitivity of PDAC to immune checkpoint blockade. The findings of our study suggest the potential of CCL2-mediated monocytes as a target for PDAC treatment.