IL-15 regulates fibrosis and inflammation in a mouse model of chronic pancreatitis

Profibrogenic role of IL-15 through IL-15 receptor alpha-mediated trans-presentation in the carbon tetrachloride-induced liver fibrosis model

Background

Inflammatory cytokines play key pathogenic roles in liver fibrosis. IL-15 is a proinflammatory cytokine produced by myeloid cells. IL-15 promotes pathogenesis of several chronic inflammatory diseases. However, increased liver fibrosis has been reported in mice lacking IL-15 receptor alpha chain (IL-15Rα), suggesting an anti-fibrogenic role for IL-15. As myeloid cells are key players in liver fibrosis and IL-15 signaling can occur independently of IL-15Rα, we investigated the requirement of IL-15 and IL-15Rα in liver fibrosis.

Methods

We induced liver fibrosis in Il15-/- , Il15ra-/- and wildtype C57BL/6 mice by the administration of carbon tetrachloride (CCl4). Liver fibrosis was evaluated by Sirius red and Mason's trichrome staining and α-smooth muscle acting immunostaining of myofibroblasts. Gene expression of collagens, matrix modifying enzymes, cytokines and chemokines was quantified by RT-qPCR. The phenotype and the numbers of intrahepatic lymphoid and myeloid cell subsets were evaluated by flow cytometry.

Results

Both Il15-/- and Il15ra-/- mice developed markedly reduced liver fibrosis compared to wildtype control mice, as revealed by reduced collagen deposition and myofibroblast content. Il15ra-/- mice showed further reduction in collagen deposition compared to Il15-/- mice. However, Col1a1 and Col1a3 genes were similarly induced in the fibrotic livers of wildtype, Il15-/- and Il15ra-/- mice, although notable variations were observed in the expression of matrix remodeling enzymes and chemokines. As expected, Il15-/- and Il15ra-/- mice showed markedly reduced numbers of NK cells compared to wildtype mice. They also showed markedly less staining of CD45+ immune cells and CD68+ macrophages, and significantly reduced inflammatory cell infiltration into the liver, with fewer pro-inflammatory and anti-inflammatory monocyte subsets compared to wildtype mice.

Conclusion

Our findings indicate that IL-15 exerts its profibrogenic role in the liver by promoting macrophage activation and that this requires trans-presentation of IL-15 by IL-15Rα.

Pretreatment with interleukin-15 attenuates inflammation and apoptosis by inhibiting NF-κB signaling in sepsis-induced myocardial dysfunction

Sepsis-induced myocardial dysfunction (SIMD) is associated with poor prognosis and increased mortality in patients with sepsis. Cytokines are important regulators of both the initiation and progression of sepsis. Interleukin-15 (IL-15), a pro-inflammatory cytokine, has been linked to protective effects against myocardial infarction and myocarditis. However, the role of IL-15 in SIMD remains unclear. We established a mouse model of SIMD via cecal ligation puncture (CLP) surgery and a cell model of myocardial injury via lipopolysaccharide (LPS) stimulation. IL-15 expression was prominently upregulated in septic hearts as well as cardiomyocytes challenged with LPS. IL-15 pretreatment attenuated cardiac inflammation and cell apoptosis and improved cardiac function in the CLP model. Similar cardioprotective effects of IL-15 pretreatment were observed in vitro. As expected, IL-15 knockdown had the opposite effect on LPS-stimulated cardiomyocytes. Mechanistically, we found that IL-15 pretreatment reduced the expression of the pro-apoptotic proteins cleaved caspase-3 and Bax and upregulated the anti-apoptotic protein Bcl-2. RNA sequencing and Western blotting further confirmed that IL-15 pretreatment suppressed the activation of nuclear factor kappa B (NF-κB) signaling in mice with sepsis. Besides, the addition of NF-κB inhibitor can significantly attenuate cardiomyocyte apoptosis compared to the control findings. Our results suggest that IL-15 pretreatment attenuated the cardiac inflammatory responses and reduced cardiomyocyte apoptosis by partially inhibiting NF-κB signaling in vivo and in vitro, thereby improving cardiac function in mice with sepsis. These findings highlight a promising therapeutic strategy for SIMD.

Chlamydial YAP activation in host endocervical epithelial cells mediates pro-fibrotic paracrine stimulation of fibroblasts

IMPORTANCE

Chronic or repeated infection of the female upper genital tract by C. trachomatis can lead to severe fibrotic sequelae, including tubal factor infertility and ectopic pregnancy. However, the molecular mechanisms underlying this effect are unclear. In this report, we define a transcriptional program specific to C. trachomatis infection of the upper genital tract, identifying tissue-specific induction of host YAP-a pro-fibrotic transcriptional cofactor-as a potential driver of infection-mediated fibrotic gene expression. Furthermore, we show that infected endocervical epithelial cells stimulate collagen production by fibroblasts and implicate chlamydial induction of YAP in this effect. Our results define a mechanism by which infection mediates tissue-level fibrotic pathology via paracrine signaling and identify YAP as a potential therapeutic target for the prevention of Chlamydia-associated scarring of the female genital tract.

Chlamydial YAP activation in host endocervical epithelial cells mediates pro-fibrotic paracrine stimulation of fibroblasts

Infection of the female genital tract by Chlamydia trachomatis can produce severe fibrotic sequelae, including tubal factor infertility and ectopic pregnancy. While infection demonstrably mediates a pro-fibrotic response in host cells, it remains unclear if intrinsic properties of the upper genital tract exacerbate chlamydial fibrosis. The relatively sterile environment of the upper genital tract is primed for a pro-inflammatory response to infection, potentially enhancing fibrosis - however, subclinical C. trachomatis infections still develop fibrosis-related sequelae. Here, we compare infection-associated and steady-state gene expression of primary human cervical and vaginal epithelial cells. In the former, we observe enhanced baseline expression and infection-mediated induction of fibrosis-associated signal factors (e.g. TGFA , IL6 , IL8 , IL20 ), implying predisposition to Chlamydia -associated pro-fibrotic signaling. Transcription factor enrichment analysis identified regulatory targets of YAP, a transcriptional cofactor induced by infection of cervical epithelial cells, but not vaginal epithelial cells. YAP target genes induced by infection include secreted fibroblast-activating signal factors; therefore, we developed an in vitro model involving coculture of infected endocervical epithelial cells with uninfected fibroblasts. Coculture enhanced fibroblast expression of type I collagen, as well as prompting reproducible (albeit statistically insignificant) induction of α-smooth muscle actin. Fibroblast collagen induction was sensitive to siRNA-mediated YAP knockdown in infected epithelial cells, implicating chlamydial YAP activation in this effect. Collectively, our results present a novel mechanism of fibrosis initiated by Chlamydia, wherein infection-mediated induction of host YAP facilitates pro-fibrotic intercellular communication. Chlamydial YAP activation in cervical epithelial cells is thus a determinant of this tissue's susceptibility to fibrosis.

Importance

Chronic or repeated infection of the female upper genital tract by C. trachomatis can lead to severe fibrotic sequelae, including tubal factor infertility and ectopic pregnancy. However, the molecular mechanisms underlying this effect are unclear. In this report, we define a transcriptional program specific to C. trachomatis infection of the upper genital tract, identifying tissue-specific induction of host YAP - a pro-fibrotic transcriptional cofactor - as a potential driver of infection-mediated fibrotic gene expression. Further, we show that infected endocervical epithelial cells stimulate collagen production by fibroblasts, and implicate chlamydial induction of YAP in this effect. Our results define a mechanism by which infection mediates tissue-level fibrotic pathology via paracrine signaling, and identify YAP as a potential therapeutic target for prevention of Chlamydia -associated scarring of the female genital tract.

IL-18-mediated neutrophil recruitment promotes acute lung injury in inflammation-mediated chronic pancreatitis

Lung injury is the most common secondary complication of pancreatitis and pancreatic malignancy. Around 60-70% of pancreatitis-related deaths are caused by lung injury; however, there is no animal model of the inflammation-mediated progressive pulmonary pathological events that contribute to acute lung injury in chronic pancreatitis (CP). Hence, we developed an inflammation-mediated mouse model and studied the pathological events that have a critical role in promoting the pathogenesis of lung injury. Our proteomic analysis of lung tissue revealed neutrophil-associated induction of neutrophil gelatinase-associated lipocalin (NGAL) and myeloperoxidase enzyme, further supporting a role for neutrophils in promoting IL-18-associated lung injury. We show that neutrophils released IL-18-induced p-NF-κB along with profibrotic and oncogenic proteins like TTF1, PDX1, and SOX9 in lung tissues of a mouse model of chronic pancreatitis. We also show that neutrophil infiltration induces TGF-β and SMAD4 and activates epithelial cells to produce other profibrotic proteins like ZO-1 and MUC2, along with the fibroblast markers FGF-1 and αSMA, that cause mesenchymal transition and accumulation of extracellular matrix collagen. Most importantly, we present evidence that IL-18 inhibition significantly alleviates CP-induced lung injury. This was further established by the finding that IL-18 gene-deficient mice showed improved lung injury by inhibition of TGF-β and fibroblast to mesenchymal transition and reduced collagen accumulation. The present study suggests that inhibition of IL-18 may be a novel treatment for CP-associated induced acute lung injury.

Gut microbiota affects pancreatic fibrotic progression through immune modulation in chronic pancreatitis

Chronic pancreatitis (CP) is characterized by chronic progressive pancreatic inflammation, which leads to the permanent damage of exocrine and endocrine cells. CP causes irreversible morphological and functional changes, and the clinical manifestations includes abdomen pain, steatorrhea and diabetes. CP induces changes in the composition of gut microbiota that could be used as potential biomarkers for pancreatic fibrosis evaluation. Gut microbiota has emerged as key regulator of immunomodulation and gut microbiota-induced immune activation has not been explored in CP. In current study, we profiled gut microbial signatures in mouse CP model, and found that higher proportion of Streptomyces, Turicibacter, Methylobacterium, Enterococcus and Candidatus_Paenicardiniummore were positively associated with the occurrence of pancreatic fibrosis. We then identified increased CD3⁺T cells and macrophage infiltration in mouse and human CP tissues by transcriptome sequencing data from GEO database. Subsequently, we demonstrated that fecal microbiota transplantation (FMT) from CP mouse (FMT-CP) exacerbated pancreatic fibrosis by increasing CD4⁺T cells and macrophage infiltration compared to fecal samples obtained from healthy mouse donor (FMT-HC). Our study describes the link between gut microbiota dysbiosis and immune activation in pancreatic fibrotic progression, and highlights the potential therapeutic roles of FMT and CP treatment.

Increased Levels of Serum IL-15 and TNF-β Indicate the Progression of Human Intracranial Aneurysm

Objective

Existing evidence suggests that chronic inflammation promotes the progression of human intracranial aneurysm (IA) and many cytokines have been detected to participate in the process of inflammation. However, rare cytokines in plasma have been used as proxies for progression of IA. This study aimed to identify novel cytokines as biomarkers to predict the development of IA.

Methods

Patients with unruptured intracranial aneurysms (UIAs) undergoing microsurgical clipping were prospectively recruited from January 2017 to June 2020 and were separated into two groups based on their ELAPSS score (low risk group < 10, intermediate-high risk group ≥ 10). Propensity score matching (PSM) was used to reduce imbalances in the baseline characteristics between groups. All blood samples were collected before surgery. A human serum 48-cytokines examination was performed to analyze the concentrations of serological cytokines. Clinical data and cytokines were compared between groups.

Results

A total of 184 patients were enrolled in this study. The low risk group contained 77 patients and 107 patients were included in the intermediate-high risk group. Finally, there were 69 patients in each group after PSM with a matching rate of 1:1. The concentrations of 3 serum cytokines were significantly increased in intermediate-high risk patients, namely, interleukin-15 (IL-15), monocyte chemoattractant protein-1 (MCP-1), and tumor necrosis factor-β (TNF-β) (P < 0.05, |log₂ fold change| > 2). The result of receiver operator characteristic (ROC)curve revealed that TNF-β had the highest predictive accuracy, with an area under the curve (AUC) value of 0.725 [95% confidence interval (CI) 0.639–0.811, P < 0.001] followed by IL-15 (AUC = 0.691, 95% CI 0.602–0.781, P < 0.001) and MCP-1 (AUC = 0.661, 95% CI 0.569–0.753, P = 0.001). Multivariate logistic analysis demonstrated high IL-15 [odds ratio (OR), 3.23; 95% CI, 1.47–7.12; P = 0.004] and high TNF-β (OR, 8.30; 95% CI, 3.25–21.25; P < 0.001) as the risk factors that correlated with intermediate-high risk of IA progression.

Conclusion

UIA patients with intermediate-high growth risk exhibited increased serum levels of IL-15, MCP-1, and TNF-β. Serum IL-15, and TNF-β could serve as biomarkers to predict the progression of UIAs.

The role of IL-15 on vulvovaginal candidiasis in mice and related adverse pregnancy outcomes

Vulvovaginal candidiasis (VVC), a major gynecological disease with high recurrence rate, increases the risk of abortion, intrauterine infection, premature rupture of membranes, and premature birth in pregnancy. However, the exact pathogenesis of this disease has yet to be elucidated. To facilitate understanding of the pathogenesis of VVC in pregnancy, this study sought to establish an animal model of vaginal infection with Candida albicans in pregnant mice. Female mice were mated with male mice, and female mice were infected with C. albicans at E4.5 (embryonic day 4.5). The weight and abortion rate of pregnant mice at E0.5, E4.5, E8.5, E11.5, and E18.5 were recorded, respectively, as well as the weights of fetus and placenta on E18.5. Fetal weight at E18.5 and the weight growth rate in the experimental mice was lower than those in the control mice, but the placenta weight at E18.5 and the abortion rate in the experimental mice were increased with those of the control mice. Hematoxylin-eosin (H&E) staining, Gomori-Grocott staining and vaginal lavage culturing were conducted to verify that the experimental mice were infected with C. albicans. Differentially expressed gene IL-15 was screened out by polymerase chain reaction (PCR) array between the two groups. Enzyme-linked immunosorbent assay (ELISA) showed that IL-15 expression in plasma of the mice was decreased in the experimental group compared with the control group. RT-qPCR confirmed that IL-15 mRNA expression was increased in placental tissues, while mRNA expression of IL-15R/JAK1-JAK3/PI3K/PDK1/AKT/P70S6K-mTOR was decreased in placental tissues. In conclusion, this study demonstrated that VVC in BALB/c pregnant mice led to a series of adverse pregnancy outcomes that were related to changes in IL-15 and its downstream signaling pathways, which may indicate a potential therapy for VVC during pregnancy in humans.

Monocytic Myeloid-Derived Suppressor Cells Inhibit Myofibroblastic Differentiation in Mesenchymal Stem Cells Through IL-15 Secretion

Background: Accumulating evidence indicates that mesenchymal stem cells (MSCs) are precursors of myofibroblasts, which play a vital role in renal fibrosis. The close interaction between MSCs and other immune cells regulates the development of multiple fibrosis-related diseases. However, the effect of myeloid-derived suppressor cells (MDSCs) on MSCs remains unexplored. Here, we investigated the effect of MDSCs on the myofibroblastic differentiation of MSCs.

Methods: MSCs were induced to undergo myofibroblastic differentiation with transforming growth factor beta 1 (TGF-β1). M-MDSCs and G-MDSCs were sorted by flow cytometry. Supernatants derived from MDSCs were administered to cultured bone marrow MSCs (BM-MSCs) undergoing TGF-β1-induced myofibroblastic differentiation. Myofibroblastic differentiation was evaluated by immunostaining. The expression of fibrosis-related genes was determined by quantitative PCR and western blot analysis. In vitro, M-MDSC supernatant or M-MDSC supernatant with interleukin (IL)-15 mAbs was administered following unilateral renal ischemia-reperfusion injury (IRI) to observe the myofibroblast differentiation of renal resident MSCs (RRMSCs) in a murine model.

Results: Myofibroblastic differentiation of MSCs was hindered when the cells were treated with MDSC-derived supernatants, especially that from M-MDSCs. The inhibitory effect of M-MDSC supernatant on the myofibroblastic differentiation of MSCs was partially mediated by IL-15-Ras-Erk1/2-Smad2/3 signaling. Treatment with M-MDSC supernatant ameliorated renal fibrosis and myofibroblastic differentiation in RRMSCs through IL-15. Additionally, M-MDSC supernatant increased M-MDSC infiltration in the kidney in a mouse IRI model. M-MDSC supernatant downregulated the adhesion and migration marker CD44 on the cell membrane of MSCs via IL-15.

Conclusion: M-MDSC-derived supernatant inhibited the TGF-β1-induced myofibroblastic differentiation of MSCs through IL-15. Our findings shed new light on the effect of MDSCs on myofibroblastic differentiation and adhesion of MSCs, which might provide a new perspective in the development of treatment strategies for renal fibrosis.

Novel Circulating and Tissue Monocytes as Well as Macrophages in Pancreatitis and Recovery

BACKGROUND AND AIMS

Acute pancreatitis (AP) is an inflammatory disease with mild to severe course that is associated with local and systemic complications and significant mortality. Uncovering inflammatory pathways that lead to progression and recovery will inform ways to monitor and/or develop effective therapies.

METHODS

We performed single-cell mass Cytometry by Time Of Flight (CyTOF) analysis to identify pancreatic and systemic inflammatory signals during mild AP (referred to as AP), severe AP (SAP), and recovery using 2 independent experimental models and blood from patients with AP and recurrent AP. Flow cytometric validation of monocytes subsets identified using CyTOF analysis was performed independently.

RESULTS

Ly6C+ inflammatory monocytes were the most altered cells in the pancreas during experimental AP, recovery, and SAP. Deep profiling uncovered heterogeneity among pancreatic and blood monocytes and identified 7 novel subsets during AP and recovery, and 6 monocyte subsets during SAP. Notably, a dynamic shift in pancreatic CD206+ macrophage population was observed during AP and recovery. Deeper profiling of the CD206+ macrophage identified 7 novel subsets during AP, recovery, and SAP. Differential expression analysis of these novel monocyte and CD206+ macrophage subsets revealed significantly altered surface (CD44, CD54, CD115, CD140a, CD196, podoplanin) and functional markers (interferon-γ, interleukin 4, interleukin 22, latency associated peptide-transforming growth factor-β, tumor necrosis factor-α, T-bet, RoRγt) that were associated with recovery and SAP. Moreover, a targeted functional analysis further revealed distinct expression of pro- and anti-inflammatory cytokines by pancreatic CD206+ macrophage subsets as the disease either progressed or resolved. Similarly, we identified heterogeneity among circulating classical inflammatory monocytes (CD14+CD16-) and novel subsets in patients with AP and recurrent AP.

CONCLUSIONS

We identified several novel monocyte/macrophage subsets with unique phenotype and functional characteristics that are associated with AP, recovery, and SAP. Our findings highlight differential innate immune responses during AP progression and recovery that can be leveraged for future disease monitoring and targeting.

IL-15 Prevents Renal Fibrosis by Inhibiting Collagen Synthesis: A New Pathway in Chronic Kidney Disease?

Chronic kidney disease (CKD), secondary to renal fibrogenesis, is a public health burden. The activation of interstitial myofibroblasts and excessive production of extracellular matrix (ECM) proteins are major events leading to end-stage kidney disease. Recently, interleukin-15 (IL-15) has been implicated in fibrosis protection in several organs, with little evidence in the kidney. Since endogenous IL-15 expression decreased in nephrectomized human allografts evolving toward fibrosis and kidneys in the unilateral ureteral obstruction (UUO) model, we explored IL-15's renoprotective role by pharmologically delivering IL-15 coupled or not with its soluble receptor IL-15Rα. Despite the lack of effects on myofibroblast accumulation, both IL-15 treatments prevented tubulointerstitial fibrosis (TIF) in UUO as characterized by reduced collagen and fibronectin deposition. Moreover, IL-15 treatments inhibited collagen and fibronectin secretion by transforming growth factor-β (TGF-β)-treated primary myofibroblast cultures, demonstrating that the antifibrotic effect of IL-15 in UUO acts, in part, through a direct inhibition of ECM synthesis by myofibroblasts. In addition, IL-15 treatments resulted in decreased expression of monocyte chemoattractant protein 1 (MCP-1) and subsequent macrophage infiltration in UUO. Taken together, our study highlights a major role of IL-15 on myofibroblasts and macrophages, two main effector cells in renal fibrosis, demonstrating that IL-15 may represent a new therapeutic option for CKD.

Chronic Pancreatitis and the Development of Pancreatic Cancer

Pancreatitis is a fibro-inflammatory disorder of the pancreas that can occur acutely or chronically as a result of the activation of digestive enzymes that damage pancreatic cells, which promotes inflammation. Chronic pancreatitis with persistent fibro-inflammation of the pancreas progresses to pancreatic cancer, which is the fourth leading cause of cancer deaths across the globe. Pancreatic cancer involves cross-talk of inflammatory, proliferative, migratory, and fibrotic mechanisms. In this review, we discuss the role of cytokines in the inflammatory cell storm in pancreatitis and pancreatic cancer and their role in the activation of SDF1α/CXCR4, SOCS3, inflammasome, and NF-κB signaling. The aberrant immune reactions contribute to pathological damage of acinar and ductal cells, and the activation of pancreatic stellate cells to a myofibroblast-like phenotype. We summarize several aspects involved in the promotion of pancreatic cancer by inflammation and include a number of regulatory molecules that inhibit that process.

Chronic inflammation promotes epithelial-mesenchymal transition-mediated malignant phenotypes and lung injury in experimentally-induced pancreatitis

Patients with chronic pancreatitis have an increased risk of pancreatic malignancy, but the mechanisms underlying this relationship are poorly understood. We developed a mouse model of chronic pancreatitis by treatment with a combination of cerulein and azoxymethane. In our model, we show that cerulein and azoxymethane treated mice develop pathological malignant phenotype and associated lung inflammation. We observed chronic pancreatitis-associated induction of proinflammatory cytokines such as interleukin-6, interleukin-15, and granulocyte-macrophage colony-stimulating factor, along with accumulation of macrophages and eosinophilic inflammation. We also observed eosinophils degranulation, pancreatic stellate cell activation-mediated epithelial-to-mesenchymal transition-associated proteins that display a pancreatic malignant phenotype including acinar-to-ductal metaplasia and acinar cell atrophy. We observed highly induced interleukin-15 that has been earlier reported to have a protective role against fibrosis and malignancy; therefore, further evaluated its role in our mouse model of chronic pancreatitis. We observed that introduction of recombinant interleukin-15 has indeed improve chronic pancreatitis-associated epithelial-to-mesenchymal transition-mediated development of a malignant phenotype in the mouse model of chronic pancreatitis. In conclusion, we present evidence that rIL-15 overexpression improves eosinophilic inflammation-induced epithelial-to-mesenchymal transition-mediated progression of pancreatic remodeling associated malignant phenotype and acute lung injury by inducing NKT cells and IFN-γ mediated innate immunity in experimental pancreatitis.

Macrophages-induced IL-18-mediated eosinophilia promotes characteristics of pancreatic malignancy

The current study presents first CP murine model that show IL-18–induced eosinophil inflammation-mediated induction of oncogenic proteins and several pathological malignant characteristics.

Reports indicate that accumulated macrophages in the pancreas are responsible for promoting the pathogenesis of chronic pancreatitis (CP). Recently, macrophage-secreted cytokines have been implicated in promoting pancreatic acinar-to-ductal metaplasia (ADM). This study aims to establish the role of accumulated macrophage-activated NLRP3-IL-18-eosinophil mechanistic pathway in promoting several characteristics of pancreatic malignancy in CP. We report that in a murine model of pancreatic cancer (PC), accumulated macrophages are the source of NLRP3-regulated IL-18, which promotes eosinophilic inflammation-mediated accumulation to periductal mucin and collagen, including the formation of ADM, pancreatic intraepithelial neoplasia (PanINs), and intraductal papillary mucinous neoplasm. Most importantly, we show improved malignant characteristics with reduced levels of oncogenes in an anti–IL-18 neutralized and IL-18 gene deficient murine model of CP. Last, human biopsies validated that NLRP3-IL-18–induced eosinophils accumulate near the ducts, showing PanINs formation in PC. Taken together, we present the evidence on the role of IL-18–induced eosinophilia in the development of PC phenotype like ADM, PanINs, and ductal cell differentiation in inflammation-induced CP.

Eosinophils in the pathogenesis of pancreatic disorders

Eosinophils comprise approximately 1-4% of total blood leukocytes that reside in the intestine, bone marrow, mammary gland, and adipose tissues to maintain innate immunity in healthy individuals. Eosinophils have four toxic granules known as major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil peroxidase (EPO), and eosinophil-derived neurotoxin (EDN), and upon degranulation, these granules promote pathogenesis of inflammatory diseases like allergy, asthma, dermatitis, and gastrointestinal disorders. Additionally, the role of eosinophils is underscored in exocrine disorders including pancreatitis. Chronic pancreatitis (CP) is an inflammatory disorder that occurs due to the alcohol consumption, blockage of the pancreatic duct, and trypsinogen mutation. Eosinophil levels are detected in higher numbers in both CP and pancreatic cancer patients compared with healthy individuals. The mechanistic understanding of chronic inflammation-induced pancreatic malignancy has not yet been reached and requires further exploration. This review provides a comprehensive summary of the epidemiology, pathophysiology, evaluation, and management of eosinophil-associated pancreatic disorders and further summarizes current evidence regarding risk factors, pathophysiology, clinical features, diagnostic evaluation, treatment, and prognosis of eosinophilic pancreatitis (EP) and pancreatic cancer.

Human umbilical cord-derived mesenchymal stem cells improve chronic pancreatitis in rats via the AKT-mTOR-S6K1 signaling pathway

Chronic pancreatitis (CP) is a progressive inflammatory disease. In clinical treatment, many patients cannot get a timely diagnosis and effective treatment due to the lack of early diagnosis indicators. Mesenchymal stem cells have immunomodulatory and anti-inflammatory effects, and have broad application prospects in treating auto-immune diseases and inflammatory diseases. This study aimed to clarify the mechanisms of human umbilical cord mesenchymal stem cells (HUCMSCs) in the treatment of CP. The rats were randomly divided into four groups, with six rats in each group: control group, CP group, CP + HUCMSCs-treated group I, and CP + HUCMSCs-treated group II. We evaluated the levels of inflammatory factors, fibrosis and apoptosis markers, detected the protein expression levels of AKT-mTOR-S6K1 and assessed histological changes of the pancreas. The results showed that HUCMSCs not only inhibited the secretion of inflammatory cytokines and activation of pancreatic stellate cells but also suppressed the apoptosis of acinar cells. Further investigation revealed that HUCMSCs noticeably suppressed the AKT-mTOR-S6K1 pathway in the pancreatic tissue of DBTC-induced CP. In addition, the therapeutic effect of HUCMSCs injected into the inferior vena cava and left gastric artery in the CP model was also observed, thus providing the basis for the clinical application of intervention measures.

Myocardin‑related transcription factor A nuclear translocation contributes to mechanical overload‑induced nucleus pulposus fibrosis in rats with intervertebral disc degeneration

Previous studies have reported that the Ras homolog family member A (RhoA)/myocardin‑related transcription factor A (MRTF‑A) nuclear translocation axis positively regulates fibrogenesis induced by mechanical forces in various organ systems. The aim of the present study was to determine whether this signaling pathway was involved in the pathogenesis of nucleus pulposus (NP) fibrosis induced by mechanical overload during the progression of intervertebral disc degeneration (IVDD) and to confirm the alleviating effect of an MRTF‑A inhibitor in the treatment of IVDD. NP cells (NPCs) were cultured on substrates of different stiffness (2.9 and 41.7 KPa), which mimicked normal and overloaded microenvironments, and were treated with an inhibitor of MRTF‑A nuclear import, CCG‑1423. In addition, bipedal rats were established by clipping the forelimbs of rats at 1 month and gradually elevating the feeding trough, and in order to establish a long‑term overload‑induced model of IVDD, and their intervertebral discs were injected with CCG‑1423 in situ. Cell viability was determined by Cell Counting Kit‑8 assay, and protein expression was determined by western blotting, immunofluorescence and immunohistochemical staining. The results demonstrated that the viability of NPCs was not affected by the application of force or the inhibitor. In NPCs cultured on stiff matrices, MRTF‑A was mostly localized in the nucleus, and the expression levels of fibrotic proteins, including type I collagen, connective tissue growth factor and α‑smooth muscle cell actin, were upregulated compared with those in NPCs cultured on soft matrices. The levels of these proteins were reduced by CCG‑1423 treatment. In rats, 6 months of upright posture activated MRTF‑A nuclear‑cytoplasmic trafficking and fibrogenesis in the NP and induced IVDD; these effects were alleviated by CCG‑1423 treatment. In conclusion, the results of the present study demonstrated that the RhoA/MRTF‑A translocation pathway may promote mechanical overload‑induced fibrogenic activity in NP tissue and partially elucidated the molecular mechanisms underlying the occurrence of IVDD.

Heat shock protein 90 inhibitor ameliorates pancreatic fibrosis by degradation of transforming growth factor-β receptor

BACKGROUND AND AIM

Pancreatic fibrosis increases pancreatic cancer risk in chronic pancreatitis (CP). Pancreatic stellate cells (PSCs) play a critical role in pancreatic fibrosis by transforming growth factor-β (TGFβ) has been shown to inhibit transforming growth factor-β receptor (TGFβR)-mediated Smad and no-Smad signaling pathways. Thus, the effects of Hsp90 inhibitor on pancreatic fibrosis are evaluated in CP mice, and the association between Hsp90 and biological functions of PSCs is further investigated in vitro.

METHODS

The effects of Hsp90 inhibitor 17AAG on pancreatic fibrosis were assessed in caerulein-induced CP mice, and primary PSCs were used to determine the role of Hsp90 inhibitor 17AAG in vitro.

RESULTS

We observed increased expression of Hsp90 in pancreatic tissues of caerulein-induced CP mice. Hsp90 inhibitor 17AAG ameliorated pancreatic inflammation and fibrosis in caerulein-induced CP mice. In vitro, Hsp90 inhibitor 17AAG inhibited TGFβ1-induced activation and extracellular matrix accumulation of PSCs by blocking TGFβR-mediated Smad2/3 and PI3K /Akt/GSK-3β signaling pathways.Hsp90 inhibitor 17AAG degraded TGFβRII by a ubiquitin-proteasome pathway, co-immunoprecipitation showed an interaction between Hsp90 and TGFβRII in PSCs.

CONCLUSIONS

The study suggests that an Hsp90 inhibitor 17AAG remarkable prevents the development of pancreatic fibrosis in caerulein-induced CP mice, and suppresses activation and extracellular matrix accumulation of PSCs in vitro. The current results provide a potential treatment strategy based on Hsp90 inhibition for pancreatic fibrosis in CP.

Experimental Modeling of Eosinophil-Associated Diseases

Eosinophils are an important subtype of leukocytes derived from bone marrow multipotent hematopoietic stem cells and represent about 1% of leukocytes in circulating blood. In homeostatic conditions, eosinophils reside in the intestine to maintain the balance of immune responses by communicating with gut microbes without causing inflammation. However, under the stressed or diseased condition, eosinophils degranulate, releasing their granule-derived cytotoxic proteins that are involved in inflammatory responses. Various eosinophil-associated inflammatory diseases are eosinophilic esophagitis (EoE), eosinophilic gastroenteritis (EG), and eosinophilic colitis (EC), together called EGID, asthma, hypereosinophilic syndrome, and eosinophilic pneumonia (EP). Eosinophil degranulation results in the release of their four toxic proteins [major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil peroxidase (EPO), and eosinophil-derived neurotoxin (EDN)] which promote disease pathogenesis. Pancreatitis is the inflammatory disease of the pancreas that arises due to blockage of the pancreatic duct, trypsinogen mutation, alcohol consumption, and repeated occurrence of pancreatitis leading to chronic pancreatitis (CP); subsequently some CP patients may also develop pancreatic cancer. The presence of eosinophils is now shown in various case reports with acute, recurrent acute, and chronic pancreatitis and pancreatic cancer indicating the role of eosinophils in the pathogenesis of various pancreatic inflammatory disorders. However, the details of eosinophil accumulation during pancreatic diseases are not well explored and need further attention. Overall, the chapter provides the current understanding of reported eosinophils associated with inflammatory diseases like EGID diseases, asthma, and pancreatic disorders, i.e., acute, chronic pancreatitis, and pancreatic cancer. This knowledge will be helpful for future studies to develop novel treatment options for the eosinophils associated diseases. Therefore, more efforts are needed to perform preclinical and clinical studies in this field for the successful development of eosinophil-targeting treatments for a variety of eosinophil-associated diseases.

Tacrolimus (FK506) treatment protects allergen-, IL-5- and IL-13-induced mucosal eosinophilia

Eosinophils are a common clinical feature associated with chronic allergic diseases, and elemental diets, systemic steroids, anti-IL-5 and anti-IL-13 treatment have shown some therapeutic promise. Herein, we present evidence that pre- and post-intraperitoneal administration of tacrolimus (FK506) is very effective in reducing CCR3/Siglec-F⁺ eosinophils in Aspergillus-challenged asthma and EoE, CD2-IL-5 induced global eosinophilia, and DOX regulated IL-13-induced asthma. We used flow cytometry and anti-major basic protein (MBP) immunostaining to examine eosinophils in the spleen, bone marrow, BALF, lung, oesophagus and intestine. Additionally, we also performed ELISA and Western blot analyses to show that tacrolimus treatment also reduces the levels of eosinophil-specific cytokines IL-4, IL-5, IL-13 and TGF-β, eosinophil-specific chemokines Eotaxin-1 and Eotaxin-2, and progenitors of target RCAN1 mRNA and protein levels. Additionally, the current investigations also show that the TGF-β-mediated oesophageal and lung fibrosis is also reduced in Aspergillus-challenged, CD2-IL-5 transgenic and DOX-responsive IL-13 mice. Mechanistically, we show that tacrolimus in vitro treatment inhibited bone marrow-derived eosinophil proliferation and viability by promoting eosinophil apoptosis that may be associated with downregulation of RCAN1. Taken together, we provide in vivo and in vitro evidence that tacrolimus ameliorates eosinophil levels and associated pathogenesis in allergen-, IL-5- and IL-13-induced EoE, EG and asthma pathogenesis. Considering tacrolimus side-effects and reactivity to several other drugs, we propose the topical use of tacrolimus for paediatric and low-dose oral for adult patients as a novel therapeutic strategy for the clinical trial to reduce mucosal eosinophilia first in steroid-refractory or elemental diet non-responsive adult EoE, EG and asthma patients.

Theranostic Nanoparticles for Pancreatic Cancer Treatment

Pancreatic cancer is one of the low vascular permeable tumors with a high mortality rate. The five-year survival period is ~5%. The field of drug delivery is at its pace in developing unique drug delivery carriers to treat high mortality rate cancers such as pancreatic cancer. Theranostic nanoparticles are the new novel delivery carriers where the carrier is loaded with both diagnostic and therapeutic agents. The present review discusses various therapeutic and theranostic nanocarriers for pancreatic cancer.

Drug discovery and formulation development for acute pancreatitis

Acute pancreatitis is a sudden inflammation and only last for a short time, but might lead to a life-threatening emergency. Traditional drug therapy is an essential supportive method for acute pancreatitis treatment, yet, failed to achieve satisfactory therapeutic outcomes. To date, it is still challenging to develop therapeutic medicine to redress the intricate microenvironment promptly in the inflamed pancreas, and more importantly, avoid multi-organ failure. The understanding of the acute pancreatitis, including the causes, mechanism, and severity judgment, could help the scientists bring up more effective intervention and treatment strategies. New formulation approaches have been investigated to precisely deliver therapeutics to inflammatory lesions in the pancreas, and some even could directly attenuate the pancreatic damages. In this review, we will briefly introduce the involved pathogenesis and underlying mechanisms of acute pancreatitis, as well as the traditional Chinese medicine and the new drug option. Most of all, we will summarize the drug delivery strategies to reduce inflammation and potentially prevent the further development of pancreatitis, with an emphasis on the bifunctional nanoparticles that act as both drug delivery carriers and therapeutics.

Cancer Microbiome; Opportunities and Challenges

BACKGROUND

Microbe-host association has emerged as a modulator in modern medicine. Cancer and its associated host microbes are collectively referred to as the cancer microbiome. The cancer microbiome is complex, and many aspects remain unclear including metabolic plasticity, microenvironment remodeling, cellular communications, and unique signatures within the host, all of which have a vital role in homeostasis and pathogenesis of host physiology. However, the role of the microbiome in cancer initiation, progression, and therapy is still poorly understood and remains to be explored.

OBJECTIVE

The objective of this review is to elucidate the role of the microbiome in cancer metabolism and the tumor microenvironment. It also focuses on the importance of therapeutic opportunities and challenges in the manipulation of the cancer microbiome.

METHODS

A literature search was conducted on the role of the microbiome in cancer initiation, progression, and therapy.

CONCLUSION

The tumor microenvironment and cancer metabolism are significant in host-microbiome interactions. The microbiome can modulate standard cancer therapies like chemotherapy and immunotherapy. Microbiome transplantation has also been demonstrated as an effective therapy against cancer. Furthermore, the modulation of the microbiome also has potential clinical outcomes in modern medicine.

IL-15 immunotherapy is a viable strategy for COVID-19

Coronavirus disease 2019 (COVID-19) is a pulmonary inflammatory disease induced by a newly recognized coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). SARS-CoV-2 infection was detected for the first time in the city of Wuhan in China and spread all over the world at the beginning of 2020. Several millions of people have been infected with SARS-CoV-2, and almost 382,867 human deaths worldwide have been reported so far. Notably, there has been no specific, clinically approved vaccine or anti-viral treatment strategy for COVID-19. Herein, we review COVID-19, the viral replication, and its effect on promoting pulmonary fibro-inflammation via immune cell-mediated cytokine storms in humans. Several clinical trials are currently ongoing for anti-viral drugs, vaccines, and neutralizing antibodies against COVID-19. Viral clearance is the result of effective innate and adaptive immune responses. The pivotal role of interleukin (IL)-15 in viral clearance involves maintaining the balance of induced inflammatory cytokines and the homeostatic responses of natural killer and CD8+ T cells. This review presents supporting evidence of the impact of IL-15 immunotherapy on COVID-19.

Berberine attenuates severity of chronic pancreatitis and fibrosis via AMPK-mediated inhibition of TGF-β1/Smad signaling and M2 polarization

Berberine (BR) acts as an AMP-activated protein kinase (AMPK) activator which possesses antioxidant and anti-inflammatory properties. In this study, we have investigated the effects of BR against cerulein-induced chronic pancreatitis (CP) via inhibition of TGF-β/Smad signaling and M2 macrophages polarization in AMPK dependent manner. Cerulein-induced CP mice were treated with BR (3 and 10 mg/kg), intraperitoneally every day for 21 days. Our results indicated that, BR treatment (10 mg/kg) significantly reduced oxidative-nitrosative stress, histological alterations, inflammatory cells infiltration and collagen deposition in pancreatic tissue. BR treatment also prevented cerulein-induced pancreatic stellate cells (PSCs) activation and extracellular matrix (ECM) deposition via downregulation of α-SMA, collagen1a, collagen3a and fibronectin expression. Mechanistically, treatment with BR significantly activated AMPK signaling as compared to cerulein-challenged mice. Further, administration of BR also inhibited TGF-β/Smad signaling and macrophages polarization in cerulein-induced CP in-vivo models and TGF-β1 stimulated RAW 264.7 macrophages in-vitro. Together, our results strongly suggest that BR treatment protected against cerulein-induced CP and associated fibrosis progression by inhibiting TGF-β1/Smad signaling and M2 macrophages polarization in an AMPK dependent manner.

Role of interleukin-15 in cardiovascular diseases

Interleukin (IL)‐15 is a recently identified cytokine, which belongs to the interleukin‐2(IL‐2) family, and plays an important role in innate and adaptive immunoreaction. Given the fact that the structure of IL‐15 is partially similar to IL‐2, they share some common biological effects, including immunoregulation. IL‐2 was proven to protect cardiac function in mouse myocardial infarction models. Cardiovascular diseases (CVDs) dominate the cause of mortality worldwide. Besides atherosclerosis, inflammation is also widely involved in the pathogenesis of many CVDs including hypertension, heart failure (HF) and aneurysm. IL‐15, as a pro‐inflammatory cytokine, is up‐regulated in some cardiovascular diseases, such as myocardial infarction and atherosclerosis. The current understanding of IL‐15, including its signal pathway and cellular function, was described. Furthermore, IL‐15 has a protective effect in myocardial infarction and myocarditis by decreasing cardiomyocyte death and improving heart function. The inhibited effect of IL‐15 in ductus arteriosus (DA) should be focused on. IL‐15 promoted atherogenesis. IL‐15 may be a good target in treatment of cardiovascular diabetology. Finally, future research direction of IL‐15 deserves attention. Since IL‐15 plays several roles in CVDs, understanding the role of the IL‐15/IL‐15R system may provide a scientific basis for the development of new approaches that use IL‐15 for the treatment of CVDs.

Statin treatment prevents the development of pulmonary arterial hypertension in a nonhuman primate model of HIV-associated PAH

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by pulmonary vascular remodeling, elevated pulmonary arterial pressure, and right heart failure. Human immunodeficiency virus (HIV)-infected individuals have a higher incidence of PAH than the non-HIV infected population and evidence suggests a role for systemic and pulmonary inflammation in the pathogenesis of HIV-associated PAH. Due to their pleiotropic effects, including immune-modulatory and anti-inflammatory effects, 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors (statins) have been considered for the treatment of PAH, with conflicting results. The effects of statins on HIV-associated PAH have not been specifically evaluated. We have developed a non-human primate (NHP) model of HIV-associated PAH that closely mimics HIV-PAH using simian immunodeficiency virus (SIV)-infected rhesus macaques (Macaca mulatta). We determined that treatment of healthy macaques with atorvastatin prior to and throughout SIV infection prevented the development of SIV-associated PAH. Additionally, SIV-infected macaques that initiated atorvastatin treatment during the early chronic disease stage had reduced incidence of PAH compared to untreated animals. Statin treatment reduced inflammatory mediators TGF-β, MIP-1α, and TNF-α and the numbers of CD14^dimCD16⁺ non-classical monocytes, and CD14⁺CCR7⁻CD163⁻CD206⁺ alveolar macrophages previously shown to be associated with SIV-PAH. These results support the concept that statins reduce inflammatory processes that contribute to PAH and may provide a safe and effective prophylactic strategy for the prevention of PAH in HIV-infected individuals.

Altered expression of MiR-186-5p and its target genes after spinal cord ischemia-reperfusion injury in rats

Spinal cord ischemia-reperfusion (I/R) injury remains an unresolved problem, and the mechanism is not fully elaborated. In a rat model of spinal cord I/R injury, we performed microarray analysis to examine the altered expression of microRNAs (miRs) at 24 h after the modelling. miR-186-5p was chosen for further study. An miR mimic or anti-miR oligonucleotide was intrathecally infused before the surgical procedure. The participation of miR-186-5p and its potential target genes based on bioinformatics analysis were analysed next. Pre-treatment with the miR-186-5p mimic improved neurological function and histological assessment scores; reduced Evans Blue extravasation; attenuated spinal cord oedema; and decreased interleukin 15 (IL-15), IL-6, IL-1β, and tumour necrosis factor-α (TNF-α) expression at 24 h after the modelling. KEGG analysis showed that the group of potential target genes of miR-186-5p was notably enriched in several signalling cascades, such as the Wnt, Hippo, and PI3K-AKT pathways. Gene Ontology (GO) analysis revealed that the group of potential target genes of miR-186-5p was significantly enriched in several biological processes, such as 'Wnt signalling pathway', 'regulation of inflammatory response', and 'Toll-like receptor signalling pathway'. We further found that Wnt5a, TLR3, and chemokine (C-X-C motif) ligand 13 (CXCL13) were upregulated after the modelling and the miR-186-5p mimic reduced the induction of the aforementioned target genes. These data provide evidence that upregulation of miR-186-5p improves neurological outcomes induced by spinal cord I/R injury and may inhibit neuroinflammation through Wnt5a-, TLR3-, or CXCL13-mediated signal pathway in spinal cord I/R injury.

Platelet-Rich Plasma and Bone Marrow-Derived Mesenchymal Stromal Cells Prevent TGF-β1-Induced Myofibroblast Generation but Are Not Synergistic when Combined: Morphological in vitro Analysis

The persistence of activated myofibroblasts is a hallmark of fibrosis of many organs. Thus, the modulation of the generation/functionality of these cells may represent a strategical anti-fibrotic therapeutic option. Bone marrow-derived mesenchymal stromal cell (MSC)-based therapy has shown promising clues, but some criticisms still limit the clinical use of these cells, including the need to avoid xenogeneic compound contamination for ex vivo cell amplification and the identification of appropriate growth factors acting as a pre-conditioning agent and/or cell delivery vehicle during transplantation, thus enabling the improvement of cell survival in the host tissue microenvironment. Many studies have demonstrated the ability of platelet-rich plasma (PRP), a source of many biologically active molecules, to positively influence MSC proliferation, survival, and functionality, as well as its anti-fibrotic potential. Here we investigated the effects of PRP, murine and human bone marrow-derived MSCs, and of the combined treatment PRP/MSCs on in vitro differentiation of murine NIH/3T3 and human HDFα fibroblasts to myofibroblasts induced by transforming growth factor (TGF)-β1, a well-known pro-fibrotic agent. The myofibroblastic phenotype was evaluated morphologically (cell shape and actin cytoskeleton assembly) and immunocytochemically (vinculin-rich focal adhesion clustering, α-smooth muscle actin and type-1 collagen expression). We found that PRP and MSCs, both as single treatments and in combination, were able to prevent the TGF-β1-induced fibroblast-myofibroblast transition. Unexpectedly, the combination PRP/MSCs had no synergistic effects. In conclusion, within the limitations related to an in vitro experimentation, our study may contribute to providing an experimental background for supporting the anti-fibrotic potential of the combination PRP/MSCs which, once translated "from bench to bedside," could potentially offer advantages over the single treatments.

Effect of NLRC5 on activation and reversion of hepatic stellate cells by regulating the nuclear factor-κB signaling pathway

BACKGROUND

The formation of liver fibrosis is mainly caused by the activation of hepatic stellate cells (HSCs) and the imbalance of extracellular matrix (ECM) production and degradation. The treatment of liver fibrosis mainly includes removing the cause, inhibiting the activation of HSCs, and inhibiting inflammation. NOD-like receptor (NLR) family, caspase activation and recruitment domain (CARD) domain containing 5/NOD27/CLR16.1 (NLRC5) is a highly conserved member of the NLR family and is involved in inflammation and immune responses by regulating various signaling pathways such as nuclear factor-κB (NF-κB) signaling. It has been found that NLRC5 plays an important role in liver fibrosis, but its specific effect and possible mechanism remain to be fully elucidated.

AIM

To investigate the role of NLRC5 in the activation and reversion of HSCs induced with transforming growth factor-β (TGF-β) and MDI, and to explore its relationship with liver fibrosis.

METHODS

A total of 24 male C57BL/6 mice were randomly divided into three groups, including normal, fibrosis, and recovery groups. Twenty-four hours after a liver fibrosis and spontaneous reversion model was established, the mice were sacrificed and pathological examination of liver tissue was performed to observe the degree of liver fibrosis in each group. LX-2 cells were cultured in vitro and treated with TGF-β1 and MDI. Real-time quantitative PCR (qPCR) and Western blot were used to analyze the expression levels of NLRC5, α-smooth muscle actin (α-SMA), and collagen type I alpha1 (Col1a1) in each group. The activity of NF-κB in each group of cells transfected with NLRC5-siRNA was detected.

RESULTS

Compared with the normal mice, the expression level of NLRC5 increased significantly (P < 0.01) in the fibrosis group, but decreased significantly in the recovery group (P < 0.01). In in vitro experiments, the content of NLRC5 was enhanced after TGF-β1 stimulation and decreased to a lower level when treated with MDI (P < 0.01). The expression of α-SMA and Col1a1 proteins and mRNAs in TGF-β1-mediated cells was suppressed by transfection with NLRC5-siRNA (P < 0.01). Western blot analysis showed that the expression of NF-κB p65 protein and phosphorylated IκBα (p-IκBα) was increased in the liver of mice in the fibrosis group but decreased in the recovery group (P < 0.01), and the protein level of nuclear p65 and p-IκBα was significantly increased after treatment with NLRC5-siRNA (P < 0.01).

CONCLUSION

NLRC5 may play a key role in the development and reversal of hepatic fibrosis through the NF-κB signaling pathway, and it is expected to be one of the clinical therapeutic targets.

Immunomodulatory effects of tacrolimus (FK506) for the treatment of allergic diseases

Tacrolimus has been used to prevent allograft rejection and also used in kidney, liver and heart transplantations. Various preclinical and clinical studies demonstrated that Tacrolimus possess immunomodulatory and anti-inflammatory properties. The mechanism of action of Tacrolimus in allergic diseases involves calcineurin inhibition, and downregulation of T-cell reactivity, IgE degranulation, and its actions on mast cells, dendritic cells, basophils, eosinophils and inhibition of transcription of proinflammatory cytokines. Herein we reviewed the Pharmacotherapeutic mechanism of action of Tacrolimus in the prevention of asthma, atopic dermatitis, and allergic conjunctivitis.