Acute Inflammatory Phase Research Articles

Protective role of Metrnl on macrophage recruitment during the acute inflammatory phase in a mouse model of myocardial infarction

Abstract Introduction Meteorin-like protein (Metrnl) is a cytokine involved in the attenuation of inflammation. Previously, a cardioprotective role of Metrnl against cardiac hypertrophy and ischemia/reperfusion has been described. After myocardial infarction (MI), macrophages recruited from the spleen, and their capacity to shift from inflammatory (M1) to reparative (M2) phases determines the fate of cardiac repair. Purpose The aim of this study was to analyse the function of Metrnl in a mouse model of permanent MI during the acute inflammatory phase. Methods Wild-type (WT), Metrnl Knock-out (Metrnl-/-) and Metrnl-reconstituted Metrnl-/- mice (AAV9-Metrnl, with myocardial-specific tropism) were subjected to MI by coronary artery ligation. After 4 days, cardiac function was assessed using echocardiography at baseline and 4 days post-MI. Monocyte populations were analysed in spleen and blood by flow cytometry, and macrophages infiltrating the infarcted myocardium by gene expression analyses. Results Echocardiographic analysis demonstrated that Metrnl deficiency led to cardiac dysfunction (FAC p=0.02) accompanied by myocardial dilation 4 days post-MI (EDV p=0.02; ESV p=0.01). On the contrary, the overexpression of Metrnl in the myocardium of AVV9-Metrnl mice restored cardiac function compared to Metrnl-/- group (FAC p=0.01, EDV p=0.04, ESV p=0.09). Furthermore, we observed a reduction in splenic monocytes (CD11b+F4/80+) in Metrnl-/- mice compared to the WT group at 4 days post-MI (p=0.06). In particular, a significant decrease in pro-inflammatory Ly6CHigh and CD86+ monocytes was noted in the spleens of Metrnl-/- mice compared to the WT group (p=0.03; p=0.04 respectively), suggesting their mobilization out of the spleen, but not in the AVV9-Metrnl group. Although the total number of Ly6CHigh and Ly6CLow monocytes in the bloodstream was similar in all groups, there was a trend to different expression in the CCR2 and CCR5 chemokine receptors (p=0.07; p=0.06 respectively). At the same time, M1 macrophage recruitment chemokines (CCL2) and inflammatory markers (TNFα) were significantly induced in the ischemic area of the infarcted myocardium compared to the remote zone in the WT and Metrnl-/- groups (CCL2 p=0.03; p=0.01 respectively; TNFα p=0.008;p=0.04 respectively). In contrast, TNFα and CCL2 genes were not induced in the ischemic area of AVV9-Metrnl mice. Regarding M2 macrophages, the Arg1 marker was significantly reduced in the ischemic zone of Metrnl-/- mice compared to the WT group (p= 0.01), while in the AVV9-Metrnl group was recovered (p= 0.04). Conclusions Our results demonstrate that the absence of Metrnl promotes the recruitment of inflammatory macrophages to the ischemic myocardium and is associated to cardiac dysfunction.

Exercise-induced inflammatory and thrombotic acute phase response in hypertensive patients

Abstract Background/Introduction Vigorous physical activity may acutely trigger the onset of an acute coronary syndrome especially in sedentary persons with established cardiovascular risk factors such as arterial hypertension. The rupture of an inflamed coronary plaque and the activation of the coagulation cascade are the main underlying mechanisms. Purpose The present study aimed to determine the effect of acute exercise on the inflammatory and thrombotic response in patients with arterial hypertension as compared to normotensive peers. Methods After excluding patients with any inflammatory or/and coronary artery disease, a total of 60 non-treated hypertensive patients and 65 normotensive individuals underwent a maximal treadmill exercise testing. Βlood samples were drawn at rest and immediately after peak exercise. High-sensitivity C-reactive protein (hsCRP), serum amyloid A (SAA), white blood cell (WBC), interleukin-6 (IL-6), and total fibrinogen (TF) levels, as well as plasminogen activator inhibitor-1 (PAI-1) activity were measured. Results All biomarkers increased with exercise, except PAI-1, which decreased (P<0.05 for the change between resting and peak exercise for all biomarkers). The normotensive group had less marked (P<0.05) exercise-induced changes than the hypertensive group in hsCRP (7.7 vs. 8.6%), SAA (5.6 vs. 11.9%), WBC (45.0 vs. 51.7%), and PAI-1 (-17.3 vs. -20.1%) and a similar (P=NS) change in IL-6 (23.8 vs. 23.0%) and TF (8.5 vs. 8.5%) (see also Figure). Conclusion(s) In conclusion, the exercise-induced inflammatory and thrombotic acute phase response seems to be more pronounced in non-treated hypertensive patients than in normotensive controls. The effect of blood-pressure lowering treatment on the exercise-induced acute phase response remains to be elucidated.Figure

Pro-inflammatory cytokines gene expression in liver and kidneys of rats exposed to a sub-lethal dose of Bitis arietans snake venom.

Bitis arietans (Puff adder) is a poisonous snake and its bite causes pain, edema, blistering, tissue damage and neutrophilia. There are limited studies on inflammatory process involved in Bitis arietans envenomation. We therefore investigated the role of proinflammatory cytokines in Bitis arietans venom (BAV)-induced liver and kidney toxicities in rats. Adult male Sprague Dawley rats were treated with BAV (0.5 mg/kg) and were sacrificed after specific time intervals (2 h, 24 h, 1 week). Blood samples were collected for liver and renal function tests and tissues were collected for histopathology and gene expression analysis of IL-1β, IL-6, and TNF-α in liver and kidneys. There was no significant difference in serum ALT activities among different treatment groups. Serum AST was significantly increased at 24 h following BAV injection. In both organs, injection of BAV resulted in mild inflammatory cell infiltration at 2 h post-dosing which normalized after 1 week. In liver, there was a significant increase in IL-1β expression in BAV-treated rats at 2 and 24 h post-dosing that reduced after one week. Significant increases in IL-6 and TNF-α were observed at 24 h and 1 week after BAV exposure. In kidneys, there were significant increases in IL-1β and TNF-α expression at 24 h that subsided after 1 week. In conclusion, a single sub-lethal dose of BAV caused an acute phase inflammation in liver and kidneys. It is most probable that a higher dose of BAV may result in greater and irreversible damage to these organs.

Outcomes of Proximal Hybrid Arterial Reconstruction in Combination with Simultaneous Amputation in Dry Atherosclerotic Gangrene of Toes

INTRODUCTION: When treating atherosclerotic gangrene of the lower limb (LL), the surgeon faces the questions about the reasonability of vascular reconstruction and the optimal timing of amputation after surgery on the LL arteries. The answer to these questions is given by assessing the state of the microvasculature of the operated limb. With sufficient development of the microvasculature and good collateral circulation, it is possible to perform a simultaneous amputation after proximal reconstruction. In this situation, a clear demarcation of the zone of necrosis and reversible ischemia is required, which can be realized by the method of ultraviolet luminescence spectroscopy. AIM: To analyze the results of hybrid reconstructions on the LL arteries with multilevel diffuse atherosclerotic lesions and dry gangrene of toes (DGT). MATERIALS AND METHODS: A prospective, controlled, non-randomized study included 29 patients suffering from critical ischemia of the lower limbs and having DGT, who were operated on in the amount of hybrid arterial reconstruction. The patients were divided into two groups: patients of group 1 (n = 14) underwent restoration of the main blood flow at the level of the iliofemoral arterial segment using a hybrid method, with simultaneous minor amputation of LL at various levels; patients of group 2 (control group, n = 15) underwent a simultaneous proximal and distal hybrid operation, providing main blood flow through at least one of the lower leg arteries, followed by a minor amputation of the lower leg at various levels over the next 4–5 days. RESULTS: There were no statistically significant differences in the groups in the degree of decrease in luminescence intensity after vascular surgery. A histological examination of intraoperative preparations of DGT revealed necrosis of the cellular microenvironment at luminescence amplitude (1.0 ± 0.05) × 105 photons at 410 nm frequency. At luminescence amplitude not exceeding this level, signs of necrobiosis were noted. Luminescence level of ≥ 1.0 × 105 photons was used as the amputation boundary. In the case of an uncomplicated vascular stage of the operation, a comparable decrease in the conventional amputation boundary was noted in the study groups. In the early postoperative period, in patients of group 1, the level of inflammation markers, average number of bed-days, and the number of thrombotic complications were lower than in the control group (p 0.05). A strong correlation was recorded between the morphological signs of the acute phase of inflammation and the intensity of chemiluminescence (r = 0.7, p 0.005). CONCLUSION: In patients with DGT, at a luminescence amplitude on the lower leg and foot not exceeding 1.0 × 105 photons at 410 nm frequency and 0.7 × 105 photons at 450 nm frequency, an effective treatment method is restoration of the main blood flow in the iliofemoral segment using a hybrid method with simultaneous minor amputation at various levels of the foot. This luminescence level is the conventional boundary between necrotic changes and reversible ischemia (necrobiosis) of the soft tissues of the LL.

Evaluation of Inflammation and Platelet Apoptosis Parameters in Obese Patients in Various Types of Anticoagulant Prophylaxis of Venous Thromboembolic Complications in Context of COVID-19

INTRODUCTION: The physical inactivity, hypoventilation, as well as chronic inflammation in obese patients aggravates their condition in various diseases. These features have become important with the advent of the COVID-19 pandemic, in which inflammation and platelet-activated coagulopathy are closely linked. AIM: To study laboratory parameters of inflammation and platelet apoptosis in obese patients using various types of anticoagulant prophylaxis of venous thromboembolic complications with the underlying COVID-19. MATERIALS AND METHODS: The study included 370 patients with COVID-19. Depending on the presence or absence of obesity and the type of parenteral anticoagulant, patients in our study were divided into groups: group 1 — non-obese + low molecular weight heparin (LMWH) (n = 114), group 2 — non-obese + unfractionated heparin (UFH) (n = 58), group 3 — obesity + LMWH (n = 76), group 4 — obesity + UFH (n = 66). The incidence of venous thromboembolic complications (VTEC), bleeding, general markers of the acute phase of inflammation, and specific markers of platelet apoptosis (phosphatidylserine and calreticulin) have been analyzed. RESULTS: At the end of hospital treatment, a decrease in ferritin levels was noted in patients both with and without obesity receiving LMWH. The concentration of calreticulin was higher in patients taking LMWH (groups 1 and 3). Phosphatidylserine levels were high in patients receiving LMWH only if they were obese. In patients taking UFH compared to LMWH, a high incidence of pulmonary embolism (PE) without a source (13.6% of cases versus 2.6%, respectively, p = 0.029) and PE with a source in the lower extremities (9.1% of cases versus 0%, respectively, p = 0.018) was found. When using LMWH, a lower incidence of bleeding was observed compared to using UFH (5.3% of cases versus 16.7%, respectively, p = 0.056). CONCLUSION: The levels of phosphatidylserine and calreticulin are higher in obese patients receiving LMWH. At the same time, patients in this group have a low incidence of VTEC and hemorrhagic complications compared to the group of patients taking UFH.

Pharmacological antagonism of Ccr2+ cell recruitment to facilitate regenerative tendon healing.

Successful tendon healing requires sufficient deposition and remodeling of new extracellular matrix at the site of injury, with this process mediating in part through fibroblast activation via communication with macrophages. Moreover, resolution of healing requires clearance or reversion of activated cells, with chronic interactions with persistent macrophages impairing resolution and facilitating the conversion to fibrotic healing. As such, modulation of the macrophage environment represents an important translational target to improve the tendon healing process. Circulating monocytes are recruited to sites of tissue injury, including the tendon, via upregulation of cytokines including Ccl2, which facilitates recruitment of Ccr2+ macrophages to the healing tendon. Our prior work has demonstrated that Ccr2-/- can modulate fibroblast activation and myofibroblast differentiation. However, this approach lacked temporal control and resulted in healing impairments. Thus, in the current study we have leveraged a Ccr2 antagonist to blunt macrophage recruitment to the healing tendon in a time-dependent manner. We first tested the effects of Ccr2 antagonism during the acute inflammatory phase and found that this had no effect on the healing process. In contrast, Ccr2 antagonism during the early proliferative/granulation tissue period resulted in significant improvements in mechanical properties of the healing tendon. Collectively, these data demonstrate the temporally distinct impacts of modulating Ccr2+ cell recruitment and Ccr2 antagonism during tendon healing and highlight the translational potential of transient Ccr2 antagonism to improve the tendon healing process.

In-vitro impacts of glyphosate on manatee lymphocytes

Exposure to contaminants, such as the herbicide glyphosate, can suppress protective immune functions. Glyphosate is the herbicide most used worldwide and has been found in plasma of more than 50 % of the Florida manatees and all-year-round in their aquatic environment. Our objectives were to analyze the consequences of glyphosate exposure on their immune responses via T-lymphocyte proliferation assays and transcriptomics. We isolated peripheral blood mononuclear cells (mainly lymphocytes) of free-ranging manatees and performed T-cell proliferation assays. We used transcriptomics to understand the consequences of glyphosate in vitro exposure. The 3 doses chosen ranged from environmentally relevant concentrations at 10 to 10,000 µg.L-1 that is considered a contamination scenario. Glyphosate caused a dose-dependent reduction in T-lymphocyte proliferation, with a significant mean reduction of 27.3 % at 10,000 µg.L-1 and up to 51.5 % in some individuals. Additionally, T-lymphocyte proliferation was significantly reduced in mid-winter compared to early winter. Transcriptomic analysis of peripheral blood mononuclear cells indicated that all doses of glyphosate (10, 1,000 and 10,000 µg.L-1) resulted in up-regulation of genes related to acute phase inflammation and inhibition of the T-lymphocyte proliferation pathway. Exposure to this contaminant along with other environmental stressors, such as extreme winters and red tide, might further affect the adaptive immune response of this threatened species.

Exposure of Cattle Breeding Herds to Naturally Co-Contaminated Zearalenone and Deoxynivalenol: The Relevance of a Urinary Mycotoxin Monitoring System for Herd Health and Food Safety.

The widespread presence of Fusarium mycotoxins in animal feed is a global issue, not only for the health of livestock but also for ensure the safety of food as an end product. High concentrations of zearalenone (ZEN) and deoxynivalenol (DON) have been detected in the diets of Japanese Black (JB) and Holstein Friesian (HF) breeding herds. Consequently, we monitored serum biochemical parameters over a long time in both herds, focusing on anti-Müllerian hormone (AMH) levels and acute-phase inflammation. Additionally, urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and progesterone levels were measured in the HF herd. The JB herd, a ZEN-dominant model with low DON contamination, demonstrated ZEN levels that exceeded the Japanese limit in the purchased total mixed rations (TMR). Conversely, the HF herd, which primary consumes DON-dominant feed with low ZEN contamination, had high DON levels in the dent corn silage. Specifically, the JB herd's TMR contained 1.79 mg/kg ZEN and 0.58 mg/kg DON, whereas the HF herd's silage had 15.3 mg/kg DON (dried sample) and 0.1 mg/kg ZEN. Enzyme-linked immunoassay were used to measure urinary ZEN-DON levels following confirmation through liquid chromatography-tandem mass spectrometry. Urinary ZEN-DON levels measured were significantly correlated (p < 0.05, r > 0.6) in both herds. In the HF herd, AMH levels increased (p = 0.01) and serum amyloid A (SAA) levels decreased (p = 0.02) when contaminated and at the end of the monitoring period. Additionally, urinary ZEN and DON levels were significantly correlated with SAA levels (ZEN: p = 0.00, r = 0.46; DON: p = 0.03, r = 0.33), with an increase in ZEN and DON levels resulting in higher SAA levels. The JB herd showed no significant differences. Additionally, in the HF herd, 8-OHdG/Cre levels increased significantly during major contamination periods (p < 0.05). Clinical data from the HF herd indicated an increase in mastitis cases and treatment rates during periods of major contamination. Abortion rates in the HF herd decreased from 22.9% (before monitoring) to 8.9% (during the high contamination period) and finally to 1% (at the end of the monitoring period), with corresponding increases in progesterone levels. ZEN-DON contamination adversely affects breeding cattle's productivity, reproductive performance, and health. Therefore, monitoring urinary ZEN-DON is valuable for detecting contaminants and ensuring the safety of food products.

Dexamethasone acetate loaded poly(ε-caprolactone) nanofibers for rat corneal chemical burn treatment

Topical eye drop approaches to treat ocular inflammation in dry eyes often face limitations such as low efficiency and short duration of drug delivery. Nanofibers serve to overcome the limitation of the short duration of action of topical eye drops used against ocular inflammation in dry eyes. Several attempts to develop suitable nanofibers have been made; however, there is no ideal solution. Here, we developed polycaprolactone (PCL) nanofibers loaded with dexamethasone acetate (DEX), prepared by electrospinning, as a potential ocular drug delivery platform for corneal injury treatment. Thirty-nine Sprague Dawley rats (7 weeks old males) were divided into four treatment groups after alkaline burns of the cornea; negative control (no treatment group); dexamethasone eyedrops (DEX group); PCL fiber (PCL group); dexamethasone loaded PCL (PCL + DEX group). We evaluated therapeutic efficacy of PCL + DEX by examining the epithelial wound healing effect, the extent of corneal opacity and neovascularization. Additionally, various inflammatory factors, including IL-1β, were investigated through immunochemistry, western blot analysis, and quantitative real-time RT-PCR (qRT-PCR). PCL + DEX group showed histologically alleviated signs of corneal inflammation compared with DEX group, which showed a decrease in IL-1β and MMP9 in the corneal stroma. The quantitative expression on day 1 after alkaline burn of pro-inflammatory markers, including IL-1β and IL-6, in the PCL + DEX group was significantly lower than that in the DEX group. Notably, PCL + DEX treatment significantly suppressed neovascularization, and enhanced the anti-inflammatory function of DEX during the acute phase of ocular inflammation. Collectively, these findings suggest that PCL + DEX may be a promising approach to effective drug delivery in corneal burn injuries.

Multifunctional injectable microspheres for osteoarthritis therapy via spatiotemporally modulating macrophage polarization and inflammation

Local injection of anti-inflammatory drugs for osteoarthritis emerged as a promising administration in the clinic, and sustained-release dosage forms have great potential for future therapeutic applications. Controlling the response of patients only in the acute inflammatory phase is currently the focus of therapeutic interventions. To relieve acute pain in patients and to improve the long-term prognosis effect of osteoarthritis treatment, we designed a two-pronged approach in this research: an injectable double-layer microsphere containing a “nonsteroidal anti-inflammatory drug - macrophage polarizing factor” was constructed. The results indicated that microspheres could regulate the intra-articular environment by inhibiting local inflammatory cytokine production, promoting macrophage polarization to the M2-phenotype, and increasing the expression of cartilage repair factors. Polymers chosen could govern the biocompatibility of microspheres and control the release sequence of the two drugs. Injection of microspheres into the degenerative articular cavity of rats leads to suppressed inflammation and well-promoted cartilage regeneration.

Podoplanin expressing macrophages and their involvement in tertiary lymphoid structures in mouse models of Sjögren's disease.

Tertiary lymphoid structures (TLSs) are formed in tissues targeted by chronic inflammation processes, such as infection and autoimmunity. In Sjögren's disease, the organization of immune cells into TLS is an important part of disease progression. Here, we investigated the dynamics of tissue resident macrophages in the induction and expansion of salivary gland TLS. We induced Sjögren's disease by cannulation of the submandibular glands of C57BL/6J mice with LucAdV5. In salivary gland tissues from these mice, we analyzed the different macrophage populations prior to cannulation on day 0 and on day 2, 5, 8, 16 and 23 post-infection using multicolored flow cytometry, mRNA gene analysis, and histological evaluation of tissue specific macrophages. The histological localization of macrophages in the LucAdV5 induced inflamed salivary glands was compared to salivary glands of NZBW/F1 lupus prone mice, a spontaneous mouse model of Sjögren's disease. The evaluation of the dynamics and changes in macrophage phenotype revealed that the podoplanin (PDPN) expressing CX3CR1+ macrophage population was increased in the salivary gland tissue during LucAdV5 induced inflammation. This PDPN+ CX3CR1+ macrophage population was, together with PDPN+CD206+ macrophages, observed to be localized in the parenchyma during the acute inflammation phase as well as surrounding the TLS structure in the later stages of inflammation. This suggests a dual role of tissue resident macrophages, contributing to both proinflammatory and anti-inflammatory processes, as well as their possible interactions with other immune cells within the inflamed tissue. These macrophages may be involved with lymphoid neogenesis, which is associated with disease severity and progression. In conclusion, our study substantiates the involvement of proinflammatory and regulatory macrophages in autoimmune pathology and underlines the possible multifaceted functions of macrophages in lymphoid cell organization.

A transdermal delivery system using microneedle patches containing poly(lactic-co-glycolic)-encapsulated acitretin nanoparticles for topical and extended treatment

Acitretin is a primary treatment for moderate-to-severe psoriasis, however, the substantial side effects associated with its daily oral administration and relapse after withdrawal significantly restrict its clinical utility. To address this challenge, we designed a transdermal delivery system using hyaluronic acid-based dissolving microneedle patches containing poly (lactic-co-glycolic)-encapsulated acitretin nanoparticles for effective topical drug administration and prolonged therapeutic effects. This microneedle exhibited favorable mechanical properties, which could easily penetrate through the thickened epidermis for intralesional drug delivery. We showed that numbers of acitretin-loaded microspheres were uniformly compacted at the bottom of needle tips, giving the microneedle dense surface morphology required for effective skin penetration, prolonged retention, and sustained release of acitretin both in vitro and in an imiquimod-induced psoriasis in vivo model. A single dose of our transdermal treatment not only alleviated the psoriasis-like skin inflammation in acute phase, but also established a long-term therapeutic effect. Moreover, the transdermal approach proved more effective than daily oral administration of the same dose of free drug, demonstrating less systemic toxicity than oral drug intake or topical cortisol application. This new system offers an innovative way for drug delivery and disease treatment, and also provides an antimicrobial control strategy for a wide range of applications.

Negative impact of maternal depressive symptoms on infancy neurodevelopment: a moderated mediation effect of maternal inflammation.

Maternal depression promotes maternal inflammation and the risk of neurodevelopmental disorder in offspring, but the role of inflammation on the association between depression and neurodevelopment in offspring has not been extensively studied in humans. This study aims to examine the mediating role of maternal inflammation on the relationship between maternal depression and neurodevelopment in infants. 146 mother-child pairs were identified from Tianjin Maternal and Child Health Education and Service Cohort (Tianjin MCHESC). Maternal depression was investigated by the Center for Epidemiologic Studies Depression Scale and the Edinburgh Postnatal Depression Scale, and depressive trajectories were identified by latent class growth analysis. Inflammatory biomarkers in the three trimesters were assessed with enzyme-linked immunoassay. The Children Neuropsychological and Behavior Scale-Revision 2016 was used to measure neurodevelopment in infants. Principal component analysis was performed to identify inflammatory condition. Stepwise multiple linear regression analysis and mediation analysis were used to identify association among maternal depression, maternal inflammation and neurodevelopment in infants. Offspring in the low and moderate maternal depression groups exhibited higher adaptive behavior development quotient than those in the high maternal depression group. Higher maternal c-reactive protein level and higher inflammatory level in acute-phase of inflammation in the first trimester, and moderate maternal depression were associated with lower adaptive behavior quotients of infants. Inflammatory level in acute-phase of inflammation in the first trimester significantly mediated the association between maternal depression and adaptive behavior development of infants, with explaining 11.85% of the association. Maternal depression could impair adaptive behavior development in infants by inflammation.

The involvement of peritoneal GATA6+ macrophages in the pathogenesis of endometriosis.

Endometriosis is a chronic inflammatory disease that causes debilitating pelvic pain in women. Macrophages are considered to be key players in promoting disease progression, as abundant macrophages are present in ectopic lesions and elevated in the peritoneum. In the present study, we examined the role of GATA6+ peritoneal macrophages on endometriosis-associated hyperalgesia using mice with a specific myeloid deficiency of GATA6. Lesion induction induced the disappearance of TIM4hi MHCIIlo residential macrophages and the influx of increased Ly6C+ monocytes and TIM4lo MHCIIhi macrophages. The recruitment of MHCIIhi inflammatory macrophages was extensive in Mac Gata6 KO mice due to the severe disappearance of TIM4hi MHCIIlo residential macrophages. Ki67 expression confirmed GATA6-dependent proliferative ability, showing different proliferative phenotypes of TIM4+ residential macrophages in Gata6f/f and Mac Gata6 KO mice. Peritoneal proinflammatory cytokines were elevated after lesion induction. When cytokine levels were compared between Gata6f/f and Mac Gata6 KO mice, TNFα at day 21 in Gata6f/f mice was higher than in Mac Gata6 KO mice. Lesion induction increased both abdominal and hind paw sensitivities. Gata6f/f mice tended to show higher sensitivity in the abdomen after day 21. Elevated expression of TRPV1 and CGRP was observed in the dorsal root ganglia after ELL induction in Gata6f/f mice until days 21 and 42, respectively. These results support that peritoneal GATA6+ macrophages are involved in the recruitment and reprogramming of monocyte-derived macrophages. The extensive recruitment of monocyte-derived macrophages in Mac Gata6 KO mice might protect against inflammatory stimuli during the resolution phase, whereas GATA6 deficiency did not affect lesion initiation and establishment at the acute phase of inflammation. GATA6+ residential macrophages act to sustain local inflammation in the peritoneum and sensitivities in the neurons, reflecting endometriosis-associated hyperalgesia.

Experimental mouse model of pulmonary fibrosis induced by nebulized LPS administration

Lipopolysaccharide (LPS)-induced lung injury is the most commonly used mouse model of acute lung inflammation that simulates the development of respiratory distress syndrome in humans. The effects of acute LPS-induced airway inflammation are well studied and associated with the neutrophil accumulation in bronchoalveolar lavage fluid (BALF), local and systemic production of proinflammatory cytokines and narrowing of the airways. Recent studies demonstrated the presence of pulmonary fibrosis characterized by increased fibroblast proliferation and excess extracellular matrix deposition in late phase of acute lung inflammation caused by LPS exposure. This work describes an experimental model of acute lung injury induced by a single aerosol injection of LPS as a reproducible in vivo model of pulmonary fibrosis. To induce lung injury, C57BL/6 mice were placed in a chamber and exposed to an aerosol containing 10 mg of LPS using an Aeroneb Lab Nebulizer delivery system. We found that 5 weeks after a single nebulized LPS administration, mice have increased production of IL-6 in BALF. Although the frequency of neutrophils was not altered, there was a decrease in the percentage of alveolar macrophages at 5 weeks after LPS exposure, indicating continued lung inflammation. Several weeks after aerosolized LPS challenge, IL-10 production in BALF was increased, as well as expression of Tgfb1, Col1a1, Il13 and Acta2, and collagen deposition in lung tissue compared to mice with acute lung inflammation. Thus, the single nebulized LPS administration represents a relevant, reproducible and physiologic model in mice allowing to investigate the mechanisms of pulmonary fibrosis development and help in the search for new therapeutic agents and approaches.

Role of Interleukin 6 in Acute Pancreatitis: A Possible Marker for Disease Prognosis.

Acute pancreatitis (AP) is a significant cause of morbidity, even in children, and is frequently associated with systemic manifestations. There are many cytokines involved in the inflammatory response characteristic of this disease. Interleukin 6 (IL-6) is one of the most important cytokines involved in AP, beginning from cellular injury and continuing to the systemic inflammatory response and distant organ involvement. IL-6 is a multifunctional cytokine that regulates acute-phase response and inflammation. It is produced by various cells and exerts its biological role on many cells through its high-affinity complex receptor. IL-6 has been investigated as a predicting maker for severe forms of AP. Many studies have validated the use of IL-6 serum levels in the first 48 h as a reliable marker for severe evolution and multisystemic involvement. Still, it has not been used in daily practice until now. This review discusses the main binding mechanisms by which IL-6 triggers cellular response and the AP pathogenetic mechanisms in which IL-6 is involved. We then emphasize the promising role of IL-6 as a prognostic marker, which could be added as a routine marker at admission in children with AP.

Pharmacological Antagonism of Ccr2+ Cell Recruitment to Facilitate Regenerative Tendon Healing.

Successful tendon healing requires sufficient deposition and remodeling of new extracellular matrix at the site of injury, with this process mediating in part through fibroblast activation via communication with macrophages. Moreover, resolution of healing requires clearance or reversion of activated cells, with chronic interactions with persistent macrophages impairing resolution and facilitating the conversion the conversion to fibrotic healing. As such, modulation of the macrophage environment represents an important translational target to improve the tendon healing process. Circulating monocytes are recruited to sites of tissue injury, including the tendon, via upregulation of cytokines including Ccl2, which facilitates recruitment of Ccr2+ macrophages to the healing tendon. Our prior work has demonstrated that Ccr2-/- can modulate fibroblast activation and myofibroblast differentiation. However, this approach lacked temporal control and resulted in healing impairments. Thus, in the current study we have leveraged a Ccr2 antagonist to blunt macrophage recruitment to the healing tendon in a time-dependent manner. We first tested the effects of Ccr2 antagonism during the acute inflammatory phase and found that this had no effect on the healing process. In contrast, Ccr2 antagonism during the late inflammatory/ early proliferative period resulted in significant improvements in mechanical properties of the healing tendon. Collectively, these data demonstrate the temporally distinct impacts of modulating Ccr2+ cell recruitment and Ccr2 antagonism during tendon healing and highlight the translational potential of transient Ccr2 antagonism to improve the tendon healing process.

An early regulatory mechanism of hyperinflammation by restricting monocyte contribution.

Innate immune cells play a key role in inflammation as a source of pro-inflammatory cytokines. However, it remains unclear how innate immunity-mediated inflammation is fine-tuned to minimize tissue damage and assure the host's survival at the early phase of systemic inflammation. The results of this study with mouse models demonstrate that the supply of monocytes is restricted depending on the magnitude of inflammation. During the acute phase of severe inflammation, monocytes, but not neutrophils, were substantially reduced by apoptosis and the remaining monocytes were dysfunctional in the bone marrow. Monocyte-specific ablation of Casp3/7 prevented monocyte apoptosis but promoted monocyte necrosis in the bone marrow, leading to elevated levels of pro-inflammatory cytokines and the increased mortality of mice during systemic inflammation. Importantly, the limitation of monocyte supply was dependent on pro-inflammatory cytokines in vivo. Consistently, a reduction of monocytes was observed in the peripheral blood during cytokine-release syndrome (CRS) patients, a pathogen-unrelated systemic inflammation induced by chimeric antigen receptor-T cell (CAR-T cell) therapy. Thus, monocytes act as a safety valve to alleviate tissue damage caused by inflammation and ensure host survival, which may be responsible for a primitive immune-control mechanism that does not require intervention by acquired immunity.

Results of a 12-Week Open-Label, Non-Interventional Study of the Efficacy and Safety of Olokizumab Therapy in Patients with Rheumatoid Arthritis after Switching from Anti-B-Cell Therapy during the SARS-CoV-2 Pandemic.

The purpose of the study was to evaluate the efficacy and safety of the drug Artlegia® (olokizumab), solution for subcutaneous injection, 160 mg/ml-0.4 ml, manufactured by R-Pharm JSC, Russia) for the treatment of patients with rheumatoid arthritis in real clinical practice after switching with rituximab during the COVID-19 pandemic. The study included 14 patients with a confirmed diagnosis of rheumatoid arthritis (RA), who were previously on rituximab therapy at a dose of 1000-500 mg twice with an interval of 2 weeks, who received at least one course of therapy with this drug. As RA worsened, patients were switched to olokizumab against the background of standard DMARDs. On weeks 0, 4, 8, and 12 after the switch, the severity of pain was assessed on the VAS scale, the number of tender and swollen joints (TJC28 and SJC28), the level of acute-phase inflammation markers, the DAS28 (disease activity score), ESR, CRP, CDAI (clinical activity index), and the functional state index HAQ (Health Assessment Questionnaire) were determined, as well as the safety profile of therapy was assessed. Data analysis was performed using median values (Me) were used for data analysis. A significant decrease in TJC28 was detected after 8 and 12 weeks of treatment with olokizumab (Artlegia®) (Me baseline = 10, Me 8 weeks = 4, Me 12 weeks = 4, p < 0.05) and a decrease in TSC28 was detected after 4, 8, and 12 weeks of treatment (Me baseline = 9, Me 4 weeks = 3.5, Me 8 weeks = 2.5, Me 12 weeks = 2.0, p < 0.05). Laboratory markers of inflammation showed a decrease in CRP and ESR levels after 4 weeks of treatment (CRP: Me4 weeks = 21, Me4 weeks = 1, p < 0.05, ESR: Mesno = 31, Me4 weeks = 7, p < 0.05). Positive dynamics persisted on 8 and 12 weeks (CRP: Me 8 weeks = 1, Me 12 weeks = 0; ESR: Me 8 weeks = 4, Me 12 weeks = 5). The level of CRP by week 4 became within the normal range, regardless of the initial values. All activity indices improved from week 4 in each evaluation period compared to baseline: DAS28-ESR: Me baseline = 5.52, Me 4 weeks = 3.59, Me 8 weeks = 3.33, Me 12 weeks = 3.22, p < 0.05; DAS28CRP: Me baseline = 5.39, Me 4 weeks = 3.71, Me 8 weeks = 3.35, Me 12 weeks = 3.45, p < 0.05; CDAI: Me baseline = 28.5, Me 4 weeks = 18.0, Me 8 weeks = 16.5, Me 12 weeks = 16.0, p < 0.05. All patients showed a reduction in pain (VAS scale) by week 8. The functional status of patients, according to the HAQ index, showed a significant decrease only by week 12 of the study: Me baseline = 1.62, Me 12 weeks = 1.31, p < 0.05. The study found that switching from rituximab to olokizumab was effective and safe during the COVID-19 pandemic.

The Value of Preoperative C-Reactive Protein to Albumin Ratio as a Prognostic Biomarker in Colon Cancer Patients.

Inflammatory acute phase proteins have been reported to play a crucial role in cancer progression. Various hematologic and inflammatory markers and scores, such as the lymphocyte-to-monocyte ratio, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, systemic inflammation score (SIS), prognostic nutritional index (PNI), Glasgow prognostic score, and, more recently, the Naples prognostic score, have been reported as significant prognostic markers. The aim of this prospective study was to evaluate the prognostic significance of the C reactive protein-to-albumin ratio (CAR) in patients with colon cancer. Materials and Methods: We conducted a prospective observational study on a series of patients who underwent curative surgery for colon cancer. The C reactive protein-to-albumin ratio was determined preoperatively, and we evaluated the correlations between the CAR and various clinical and pathological parameters, as well as the correlation with Overall and Relapse-free survival. Furthermore, we compared the accuracy of the CAR with that of the Naples score. Results: One hundred and ten patients were included in the study. We set 0.4927 as the cut-off value for the CAR according to a receiver operating characteristic curve analysis. Based on the cut-off value, patients were divided into a low CAR group and a high CAR group. The preoperative CAR exhibited statistically significant correlation with tumor volume, T and N stage, number of positive lymph nodes, and grade of tumor differentiation. We also demonstrated a positive correlation between high CAR values and a higher Naples score (p = 0.0005), even when a subgroup analysis was performed for each group individually. Conclusions: The preoperative CAR is a useful prognostic marker in patients with colon cancer. These results may help to design strategies to personalize targeted management approaches among colon cancer patients.