Chemokines in tissue-specific and microenvironment-specific lymphocyte homing

A novel metric-based approach of scoring early host immune response from oro-nasopharyngeal swabs predicts COVID-19 outcome

Unpredictable fatal outcome of COVID-19 is attributed to dysregulated inflammation. Impaired early adaptive immune response leads to late-stage inflammatory outcome. The purpose of this study was to develop biomarkers for early detection of host immune impairment at first diagnosis from leftover RNA samples, which may in turn identify high risk patients. Leftover RNA samples of COVID-19 patients at first diagnosis were stored. Following prospective follow-up, the samples were shorted and categorized into outcome groups. Impaired adaptive T cell response (severity score) and Impaired IL-10 response (undetectable IL-10 in the presence of high expression of a representative interferon response gene) were determined by RT-PCR based assay. We demonstrate that a T cell response based 'severity score' comprising rational combination of Ct values of a target genes' signature can predict high risk noncomorbid potentially critical COVID-19 patients with a sensitivity of 91% (95% CI 58.7-99.8) and specificity of 92.6% (95% CI 75.7-99) (AUC:0.88). Although inclusion of comorbid patients reduced sensitivity to 77% (95% CI 54.6-92.2), the specificity was still 94% (95% CI 79.8-99.3) (AUC:0.82). The same for 'impaired IL-10 response' were little lower to predict high risk noncomorbid patients 64.2% (95% CI 35.1-87.2) and 82% (95% CI 65.5-93.2) respectively. Inclusion of comorbid patients drastically reduce sensitivity and specificity51.6% (95% CI 33.1-69.8) and 80.5% (95% CI 64.0-91.8) respectively. As best of our knowledge this is the first demonstration of a metric-based approach showing the 'severity score' as an indicator of early adoptive immune response, could be used as predictor of severe COVID-19 outcome at the time of first diagnosis using the same leftover swab RNA. The work flow could reduce expenditure and reporting time of the prognostic test for an earliest clinical decision ensuring possibility of early rational management.

Neutrophil Infiltration and Function in the Pathogenesis of Inflammatory Airspace Disease

Neutrophils are an important cell type often considered the body's first responders to inflammatory insult or damage. They are recruited to the tissue of the lungs in patients with inflammatory airspace diseases and have unique and complex functions that range from helpful to harmful. The uniqueness of these functions is due to the heterogeneity of the inflammatory cascade and retention in the vasculature. Neutrophils are known to marginate, or remain stagnant, in the lungs even in nondisease conditions. This review discusses the ways in which the recruitment, presence, and function of neutrophils in the airspace of the lungs are unique from those of other tissues, and the complex effects of neutrophils on pathogenesis. Inflammatory mediators produced by neutrophils, such as neutrophil elastase, proresolving mediators, and neutrophil extracellular traps, dramatically affect the outcomes of patients with disease of the lungs.

Systematic Assessment of Human CCR7 Signalling Using NanoBRET Biosensors Points towards the Importance of the Cellular Context

The human CC chemokine receptor 7 (CCR7) is activated by two natural ligands, CC chemokine ligand 19 (CCL19) and 21 (CCL21). The CCL19-CCL21-CCR7 axis has been extensively studied in vitro, but there is still debate over whether CCL21 is an overall weaker agonist or if the axis displays biased signalling. In this study, we performed a systematic analysis at the transducer level using NanoBRET-based methodologies in three commonly used cellular backgrounds to evaluate pathway and ligand preferences, as well as ligand bias and the influence of the cellular system thereon. We found that both CCL19 and CCL21 activated all cognate G proteins and some non-cognate couplings in a cell-type-dependent manner. Both ligands recruited β-arrestin1 and 2, but the potency was strongly dependent on the cellular system. Overall, CCL19 and CCL21 showed largely conserved pathway preferences, but small differences were detected. However, these differences only consolidated in a weak ligand bias. Together, these data suggest that CCL19 and CCL21 share mostly overlapping, weakly biased, transducer profiles, which can be influenced by the cellular context.

Transcriptome analysis reveals molecular signature and cell-type difference of Homo sapiens endothelial-to-mesenchymal transition

Endothelial-to-mesenchymal transition (EndoMT), a specific form of epithelial-to-mesenchymal transition, drives a growing number of human (Homo sapiens) pathological conditions. This emerging knowledge opens a path to discovering novel therapeutic targets for many EndoMT-associated disorders. Here, we constructed an atlas of the endothelial-cell transcriptome and demonstrated EndoMT-induced global changes in transcriptional gene expression. Our gene ontology analyses showed that EndoMT could be a specific checkpoint for leukocyte chemotaxis, adhesion, and transendothelial migration. We also identified distinct gene expression signatures underlying EndoMT across arterial, venous, and microvascular endothelial cells. We performed protein-protein interaction network analyses, identifying a class of highly connected hub genes in endothelial cells from different vascular beds. Moreover, we found that the short-chain fatty acid acetate strongly inhibits the transcriptional program of EndoMT in endothelial cells from different vascular beds across tissues. Our results reveal the molecular signature and cell-type difference of EndoMT across distinct tissue- and vascular-bed-specific endothelial cells, providing a powerful discovery tool and resource value. These results suggest that therapeutically manipulating the endothelial transcriptome could treat an increasing number of EndoMT-associated pathological conditions.

Altered Tumor Necrosis Factor Response in Neurologic Postacute SARS-CoV-2 Syndrome

Neurologic manifestations of postacute sequelae after SARS-CoV-2 infection (neuro-PASC) are common; however, the underlying drivers of those symptoms remain poorly understood. Prior work has postulated that immune dysregulation leads to ongoing neuroinflammation. We aimed to identify the cytokines involved in that immune dysregulation by comparing 37 plasma cytokine profiles among 20 case patients with neuro-PASC to 20 age- and gender-matched controls. Neuro-PASC cases were defined as individuals with self-reported persistent headache, general malaise, and anosmia or ageusia at least 28 days post-SARS-CoV-2 infection. As a sensitivity analysis, we repeated the main analysis among only participants of Hispanic heritage. In total, 40 specimens were tested. Participants were an average of 43.5 years old (interquartile range 30-52), 20 (50.0%) of whom identified as women. Levels of tumor necrosis factor alpha (TNFα) were 0.76 times lower [95% confidence interval (CI) 0.62-0.94] among cases of neuro-PASC compared with controls, as were levels of C-C motif chemokine 19 (CCL19) (0.67; 95% CI 0.50-0.91), C-C motif chemokine 2 (CCL2) (0.72; 95% CI 0.55-0.95), chemokine interferon-gamma inducible protein 10 (CXCL10) (0.63; 95% CI 0.42-0.96), and chemokine interferon-gamma inducible protein 9 (CXCL9) (0.62; 95% CI 0.38-0.99). Restricting analysis of TNF and CCL19 to participants who identified as Hispanic did not alter results. We noted a reduction in TNFα and down-stream chemokines among patients with neuro-PASC, suggesting an overall immune attenuation.

Human skin-resident CD8+ T cells require RUNX2 and RUNX3 for induction of cytotoxicity and expression of the integrin CD49a

The integrin CD49a marks highly cytotoxic epidermal-tissue-resident memory (T_RM) cells, but their differentiation from circulating populations remains poorly defined. We demonstrate enrichment of RUNT family transcription-factor-binding motifs in human epidermal CD8⁺CD103⁺CD49a⁺ T_RM cells, paralleled by high RUNX2 and RUNX3 protein expression. Sequencing of paired skin and blood samples revealed clonal overlap between epidermal CD8⁺CD103⁺CD49a⁺ T_RM cells and circulating memory CD8⁺CD45RA^-CD62L⁺ T cells. In vitro stimulation of circulating CD8⁺CD45RA^-CD62L⁺ T cells with IL-15 and TGF-β induced CD49a expression and cytotoxic transcriptional profiles in a RUNX2- and RUNX3-dependent manner. We therefore identified a reservoir of circulating cells with cytotoxic T_RM potential. In melanoma patients, high RUNX2, but not RUNX3, transcription correlated with a cytotoxic CD8⁺CD103⁺CD49a⁺ T_RM cell signature and improved patient survival. Together, our results indicate that combined RUNX2 and RUNX3 activity promotes the differentiation of cytotoxic CD8⁺CD103⁺CD49a⁺ T_RM cells, providing immunosurveillance of infected and malignant cells.

Influenza Virus Infection during Pregnancy as a Trigger of Acute and Chronic Complications

Influenza A virus (IAV) infection during pregnancy disrupts maternal and fetal health through biological mechanisms, which are to date poorly characterised. During pregnancy, the viral clearance mechanisms from the lung are sub-optimal and involve hyperactive innate and adaptive immune responses that generate wide-spread inflammation. Pregnancy-related adaptations of the immune and the cardiovascular systems appear to result in delayed recovery post-viral infection, which in turn promotes a prolonged inflammatory phenotype, increasing disease severity, and causing maternal and fetal health problems. This has immediate and long-term consequences for the mother and fetus, with complications including acute cardiopulmonary distress syndrome in the mother that lead to perinatal complications such as intrauterine growth restriction (IUGR), and birth defects; cleft lip, cleft palate, neural tube defects and congenital heart defects. In addition, an increased risk of long-term neurological disorders including schizophrenia in the offspring is reported. In this review we discuss the pathophysiology of IAV infection during pregnancy and its striking similarity to other well-established complications of pregnancy such as preeclampsia. We discuss general features of vascular disease with a focus on vascular inflammation and define the "Vascular Storm" that is triggered by influenza infection during pregnancy, as a pivotal disease mechanism for short and long term cardiovascular complications.

Cellular Electrical Impedance as a Method to Decipher CCR7 Signalling and Biased Agonism

The human C-C chemokine receptor type 7 (CCR7) has two endogenous ligands, C-C chemokine ligand 19 (CCL19) and CCL21, displaying biased agonism reflected by a pronounced difference in the level of β-arrestin recruitment. Detecting this preferential activation generally requires the use of separate, pathway-specific label-based assays. In this study, we evaluated an alternative methodology to study CCR7 signalling. Cellular electrical impedance (CEI) is a label-free technology which yields a readout that reflects an integrated cellular response to ligand stimulation. CCR7-expressing HEK293 cells were stimulated with CCL19 or CCL21, which induced distinct impedance profiles with an apparent bias during the desensitisation phase of the response. This discrepancy was mainly modulated by differential β-arrestin recruitment, which shaped the impedance profile but did not seem to contribute to it directly. Pathway deconvolution revealed that Gαi-mediated signalling contributed most to the impedance profile, but Gαq- and Gα12/13-mediated pathways were also involved. To corroborate these results, label-based pathway-specific assays were performed. While CCL19 more potently induced β-arrestin2 recruitment and receptor internalisation than CCL21, both chemokines showed a similar level of Gαi protein activation. Altogether, these findings indicate that CEI is a powerful method to analyse receptor signalling and biased agonism.

Persistence of mature dendritic cells, TH2A, and Tc2 cells characterize clinically resolved atopic dermatitis under IL-4Rα blockade

Therapeutic options for autoimmune diseases typically consist of broad and targeted immunosuppressive agents. However, sustained clinical benefit is rarely achieved, as the disease phenotype usually returns after cessation of treatment. To better understand tissue-resident immune memory in human disease, we investigated patients with atopic dermatitis (AD) who underwent short-term or long-term treatment with the IL-4Rα blocker dupilumab. Using multi-omics profiling with single-cell RNA sequencing and multiplex proteomics, we found significant decreases in overall skin immune cell counts and normalization of transcriptomic dysregulation in keratinocytes consistent with clearance of disease. However, we identified specific immune cell populations that persisted for up to a year after clinical remission while being absent from healthy controls. These populations included LAMP3 + CCL22+ mature dendritic cells, CRTH2 + CD161 + T helper ("TH2A") cells, and CRTAM + cytotoxic T cells, which expressed high levels of CCL17 (dendritic cells) and IL13 (T cells). TH2A cells showed a characteristic cytokine receptor constellation with IL17RB, IL1RL1 (ST2), and CRLF2 expression, suggesting that these cells are key responders to the AD-typical epidermal alarmins IL-25, IL-33, and TSLP, respectively. We thus identified disease-linked immune cell populations in resolved AD indicative of a persisting disease memory, facilitating a rapid response system of epidermal-dermal cross-talk between keratinocytes, dendritic cells, and T cells. This observation may help to explain the disease recurrence upon termination of immunosuppressive treatments in AD, and it identifies potential disease memory-linked cell types that may be targeted to achieve a more sustained therapeutic response.

Vedolizumab and Extraintestinal Manifestations in Inflammatory Bowel Disease

In Crohn's disease and ulcerative colitis, inflammation is not limited to the digestive tract. Extraintestinal manifestations (EIMs), which affect up to 50% of patients, can substantially impair quality of life. EIMs may parallel luminal disease activity or have an independent course. They most commonly involve the musculoskeletal system (e.g., peripheral or axial arthritis) and skin (e.g., erythema nodosum and pyoderma gangrenosum). Less commonly, the hepatobiliary tract (e.g., primary sclerosing cholangitis [PSC]) and the eye (e.g., episcleritis, scleritis, and uveitis) are involved. Although the pathophysiology of EIMs is poorly understood, they are likely either manifestations of a primary systemic immune disease with variable expression amongst organs, or secondary phenomena to bowel inflammation. Additional pathophysiologic mechanisms may include aberrant lymphocyte homing mediated by ectopic expression of gut-specific chemokines and adhesion molecules, cross-reactivity between microbial and self-antigens, autoantibodies against epitopes shared by the intestine and extraintestinal tissues, elevated serum concentrations of cytokines, and alterations in innate immunity. Many EIMs independent of intestinal disease activity can be successfully treated with tumor necrosis factor (TNF) antagonists. The efficacy of vedolizumab-a monoclonal antibody targeting the α4β7 integrin-for the treatment of EIMs is uncertain, but data are emerging from post hoc analyses of randomized controlled trials, prospective and retrospective cohort studies, and case series. Vedolizumab may be effective in treating EIMs related to luminal disease activity (e.g., type 1 peripheral arthritis and erythema nodosum) but has not shown biochemical improvement in PSC. Its postulated role in the development of de novo EIMs is heavily confounded by the high proportion of patients previously exposed to TNF antagonists; new EIMs could result from TNF antagonist treatment cessation rather than being caused by vedolizumab. A common limitation of clinical studies is the lack of multidisciplinary involvement in the diagnosis and monitoring of EIMs, which may lead to misdiagnosis and overreporting. Future studies should rigorously measure EIMs in parallel with objective measures of luminal disease activity to provide more robust data on the relative efficacy of new drugs, especially as increasing numbers of gut-selective compounds enter clinical development.

Stable Epigenetic Programming of Effector and Central Memory CD4 T Cells Occurs Within 7 Days of Antigen Exposure In Vivo

T cell immunological memory is established within days of an infection, but little is known about the in vivo changes in gene regulatory networks accounting for their ability to respond more efficiently to secondary infections. To decipher the timing and nature of immunological memory we performed genome-wide analyses of epigenetic and transcriptional changes in a mouse model generating antigen-specific T cells. Epigenetic reprogramming for Th differentiation and memory T cell formation was already established by the peak of the T cell response after 7 days. The Th memory T cell program was associated with a gain of open chromatin regions, enriched for RUNX, ETS and T-bet motifs, which remained stable for 56 days. The epigenetic programs for both effector memory, associated with T-bet, and central memory, associated with TCF-1, were established in parallel. Memory T cell-specific regulatory elements were associated with greatly enhanced inducible Th1-biased responses during secondary exposures to antigen. Furthermore, memory T cells responded in vivo to re-exposure to antigen by rapidly reprograming the entire ETS factor gene regulatory network, by suppressing Ets1 and activating Etv6 expression. These data show that gene regulatory networks are epigenetically reprogrammed towards memory during infection, and undergo substantial changes upon re-stimulation.

Enhanced lymphatic delivery of nanomicelles encapsulating CXCR4-recognizing peptide and doxorubicin for the treatment of breast cancer

Lymph node metastases in cancer patients are associated with high aggressiveness, poor prognosis, and short survival time. The chemokine receptor 4 (CXCR4)/stroma derived factor 1α (CXCL12) biological axis plays a critical role in the spread of cancer cells. Designing effective delivery systems that can successfully deliver CXCR4 antagonists to lymph nodes, which are rich in CXCR4-overexpressing cancer cells, for controlling cancer metastasis remain challenging. In this study, we demonstrated that such a challenge may be alleviated by developing nanometer-sized polyethylene glycol-phosphatidylethanolamine (PEG-PE) micelles for the co-delivery of the CXCR4 antagonistic peptide E5 and doxorubicin (M-E5-Dox). This nanomicelle platform enables the preferential accumulation of cargos into lymph nodes and thus can better inhibit cancer metastasis and enhance antitumor efficacy than either free drugs or single drug-loaded micelles in breast cancer-bearing mouse models. Hence, M-E5-Dox is expected to be a potential therapeutic agent that would improve the clinical benefits of breast cancer therapy and treatment of various CXCR4-overexpressing malignancies.

Targeted pharmacologic immunomodulation for inborn errors of immunity

Inborn errors of immunity consist of over 400 known single gene disorders that may manifest with infection susceptibility, autoimmunity, autoinflammation, hypersensitivity and cancer predisposition. Most patients are treated symptomatically with immunoglobulin replacement, prophylactic antimicrobials or broad immunosuppression pertaining to their disease phenotype. Other than haematopoietic stem cell transplantation, the aforementioned treatments do little to alter disease morbidity or mortality. Further, many patients may not be transplant candidates. In this review, we describe monogenic disorders affecting leucocyte migration, disorders of immune synapse formation and dysregulation of immune cell signal transduction. We highlight the use of off-label small molecules and biologics mechanistically targeted to altered disease pathophysiology of such diseases.

AGTR1 promotes lymph node metastasis in breast cancer by upregulating CXCR4/SDF-1α and inducing cell migration and invasion

The angiotensin II type I receptor (AGTR1) has a strong influence on tumor growth, angiogenesis, inflammation and immunity. However, the role of AGTR1 on lymph node metastasis (LNM) in breast cancer, which correlates with tumor progression and patient survival, has not been examined. AGTR1 was highly expressed in lymph node-positive tumor tissues, which was confirmed by the Oncomine database. Next, inhibition of AGTR1 reduced tumor growth and LNM in orthotopic xenografts by bioluminescence imaging (BLI). Losartan, an AGTR1-specific inhibitor, decreased the chemokine pair CXCR4/SDF-1α levels in vivo and inhibited AGTR1-induced cell migration and invasion in vitro. Finally, the molecular mechanism of AGTR1-induced cell migration and LNM was assessed by knocking down AGTR1 in normal cells or CXCR4 in AGTR1^high cells. AGTR1-silenced cells treated with losartan showed lower CXCR4 expression. AGTR1 overexpression caused the upregulation of FAK/RhoA signaling molecules, while knocking down CXCR4 in AGTR1^high cells downregulated these molecules. Collectively, AGTR1 promotes LNM by increasing the chemokine pair CXCR4/SDF-1α and tumor cell migration and invasion. The potential mechanism of AGTR1-mediated cell movement relies on activating the FAK/RhoA pathway. Our study indicated that inhibiting AGTR1 may be a potential therapeutic target for LNM in early-stage breast cancer.

Selective BET-bromodomain inhibition by JQ1 suppresses dendritic cell maturation and antigen-specific T-cell responses

Bromo- and extra-terminal domain (BET) inhibitors represent potential therapeutic approaches in solid and hematological malignancies that are currently analyzed in several clinical trials. Additionally, BET are involved in the epigenetic regulation of immune responses by macrophages and dendritic cells (DCs), that play a central role in the regulation of immune responses, indicating that cancer treatment with BET inhibitors can promote immunosuppressive effects. The aim of this study was to further characterize the effects of selective BET inhibition by JQ1 on DC maturation and DC-mediated antigen-specific T-cell responses. Selective BET inhibition by JQ1 impairs LPS-induced DC maturation and inhibits the migrational activity of DCs, while antigen uptake is not affected. JQ1-treated DCs show reduced ability to induce antigen-specific T-cell proliferation. Moreover, antigen-specific T cells co-cultured with JQ1-treated DCs exhibit an inactive phenotype and reduced cytokine production. JQ1-treated mice show reduced immune responses in vivo to sublethal doses of LPS, characterized by a reduced white blood cell count, an immature phenotype of splenic DCs and T cells and lower blood levels of IL-6. In our study, we demonstrate that selective BET inhibition by JQ1, a drug currently tested in clinical trials for malignant diseases, has profound effects on DC maturation and DC-mediated antigen-specific T-cell responses. These immunosuppressive effects can result in the induction of possible infectious side effects in cancer treatments. In addition, based on our results, these compounds should not be used in combinatorial regimes using immunotherapeutic approaches such as check point inhibitors, T-cell therapies, or vaccines.

A novel humanized mouse model to study the function of human cutaneous memory T cells in vivo in human skin

Human skin contains a population of memory T cells that supports tissue homeostasis and provides protective immunity. The study of human memory T cells is often restricted to in vitro studies and to human PBMC serving as primary cell source. Because the tissue environment impacts the phenotype and function of memory T cells, it is crucial to study these cells within their tissue. Here we utilized immunodeficient NOD-scid IL2rγ^null (NSG) mice that carried in vivo-generated engineered human skin (ES). ES was generated from human keratinocytes and fibroblasts and was initially devoid of skin-resident immune cells. Upon adoptive transfer of human PBMC, this reductionist system allowed us to study human T cell recruitment from a circulating pool of T cells into non-inflamed human skin in vivo. Circulating human memory T cells preferentially infiltrated ES and showed diverse functional profiles of T cells found in fresh human skin. The chemokine and cytokine microenvironment of ES closely resembled that of non-inflamed human skin. Upon entering the ES T cells assumed a resident memory T cell-like phenotype in the absence of infection, and a proportion of these cutaneous T cells can be locally activated upon injection of monocyte derived dendritic cells (moDCs) that presented Candida albicans. Interestingly, we found that CD69⁺ memory T cells produced higher levels of effector cytokines in response to Candida albicans, compared to CD69^- T cells. Overall, this model has broad utility in many areas of human skin immunology research, including the study of immune-mediated skin diseases.

The cellular and humoral immune response to influenza vaccination is comparable in asthmatic and healthy subjects

Annual influenza vaccination is recommended as a preventive measure for all patients with asthma since asthma exacerbations in children and adults are associated to viral infections including influenza. There is concern about the adequate immune response in asthmatics with ICS treatment. The production of antibodies to influenza in asthmatics has been demonstrated. However, cellular immunity is poorly understood. The aim of the study was to compare the humoral and cellular immune responses to influenza vaccine in asthmatic and healthy subjects. Twenty-five asthmatic patients attending the Allergy and Clinical Immunology Service at the Hospital General de Mexico and 25 healthy adults were included. Blood samples were obtained before, 4 and 12 months after immunization with influenza vaccine, influenza-specific antibodies were determined by the hemagglutination inhibition test and influenza-specific memory B, TCD4+, and TCD8 + lymphocytes were determined by flow cytometry. All the asthmatic patients received ICS treatment. The Geometric Mean titers for all influenza serotypes were similar in both groups; seropositivity and the cellular immune response increased in both groups over time and was comparable. Influenza vaccination in asthmatic patients with immunotherapy and ICS achieved protective antibody levels and cellular immunity over time comparable to healthy subjects.

MicroRNA Expression Profiling on Paired Primary and Lymph Node Metastatic Breast Cancer Revealed Distinct microRNA Profile Associated With LNM

Breast cancer (BC) is the foremost cause of cancer-related deaths in women. BC patients are oftentimes presented with lymph node metastasis (LNM), which increases their risk of recurrence. Compelling data have recently implicated microRNAs in promoting BC metastasis. Therefore, the identification of microRNA (miRNA)-based molecular signature associated with LNM could provide an opportunity for a more personalized treatment for BC patients with high risk of LNM. In current study, we performed comprehensive miRNA profiling in matched primary breast and LNM and identified 40 miRNAs, which were differentially expressed in LNM compared to primary tumors. The expression of 14 miRNAs (Up: hsa-miR-155-5p, hsa-miR-150-5p, hsa-miR-146a-5p, hsa-miR-142-5p and down: hsa-miR-200a-3p, hsa-miR-200b-3p, hsa-miR-200c-3p, hsa-miR-205-5p, hsa-miR-210-3p, hsa-miR-214-3p, hsa-miR-141-3p, hsa-miR-127-3p, hsa-miR-125a-5p, and hsa-let-7c-5p) was subsequently validated in a second cohort of 32 breast and 32 matched LNM tumor tissues. Mechanistically, forced expression of hsa-miR-205-5p, or hsa-miR-214-3p epigenetically inhibited MDA-MB-231 cell proliferation, colony formation, and cell migration. Global gene expression profiling on MDA-MB-231 cells overexpressing hsa-miR-205-5p, or hsa-miR-214-3p in combination with in silico target prediction and ingenuity pathway analyses identified multiple bona fide targets for hsa-miR-205-5p, hsa-miR-214-3p affecting cellular proliferation and migration. Interestingly, interrogation of the expression levels of hsa-miR-205 and hsa-miR-214 in the METABRIC breast cancer dataset revealed significantly poor overall survival in patients with downregulated expression of miR-205 [HR = 0.75 (0.61–0.91)], p = 0.003 and hsa-miR-214 [HR = 0.74 (0.59–0.93) p = 0.008]. Our data unraveled the miRNA-transcriptional landscape associated with LNM and provide novel insight on the role of several miRNAs in promoting BC LNM, and suggest their potential utilization in the clinical management of BC patients.

MicroRNA Expression Profiling on Paired Primary and Lymph Node Metastatic Breast Cancer Revealed Distinct microRNA Profile Associated With LNM

Breast cancer (BC) is the foremost cause of cancer-related deaths in women. BC patients are oftentimes presented with lymph node metastasis (LNM), which increases their risk of recurrence. Compelling data have recently implicated microRNAs in promoting BC metastasis. Therefore, the identification of microRNA (miRNA)-based molecular signature associated with LNM could provide an opportunity for a more personalized treatment for BC patients with high risk of LNM. In current study, we performed comprehensive miRNA profiling in matched primary breast and LNM and identified 40 miRNAs, which were differentially expressed in LNM compared to primary tumors. The expression of 14 miRNAs (Up: hsa-miR-155-5p, hsa-miR-150-5p, hsa-miR-146a-5p, hsa-miR-142-5p and down: hsa-miR-200a-3p, hsa-miR-200b-3p, hsa-miR-200c-3p, hsa-miR-205-5p, hsa-miR-210-3p, hsa-miR-214-3p, hsa-miR-141-3p, hsa-miR-127-3p, hsa-miR-125a-5p, and hsa-let-7c-5p) was subsequently validated in a second cohort of 32 breast and 32 matched LNM tumor tissues. Mechanistically, forced expression of hsa-miR-205-5p, or hsa-miR-214-3p epigenetically inhibited MDA-MB-231 cell proliferation, colony formation, and cell migration. Global gene expression profiling on MDA-MB-231 cells overexpressing hsa-miR-205-5p, or hsa-miR-214-3p in combination with in silico target prediction and ingenuity pathway analyses identified multiple bona fide targets for hsa-miR-205-5p, hsa-miR-214-3p affecting cellular proliferation and migration. Interestingly, interrogation of the expression levels of hsa-miR-205 and hsa-miR-214 in the METABRIC breast cancer dataset revealed significantly poor overall survival in patients with downregulated expression of miR-205 [HR = 0.75 (0.61-0.91)], p = 0.003 and hsa-miR-214 [HR = 0.74 (0.59-0.93) p = 0.008]. Our data unraveled the miRNA-transcriptional landscape associated with LNM and provide novel insight on the role of several miRNAs in promoting BC LNM, and suggest their potential utilization in the clinical management of BC patients.

Chemotactic effects in reaction-diffusion equations for inflammation

Predator-prey systems are used to model time-dependent virus and lymphocyte population during a liver infection and to discuss the influence of chemotactic behavior on the chronification tendency of such infections. Therefore, a model family of reaction-diffusion equations is presented, and the long-term behavior of the solutions is estimated by a critical value containing the reaction strength, the diffusion rate, and the extension of the liver domain. Fourier techniques are applied to evaluate the influence of chemotactic behavior of the immune response to the long-term behavior of locally linearized models. It turns out that the chemotaxis is a subordinated influence with respect to the chronification of liver infections.

Gene-environment interactions in primary atopic disorders

Environmental factors modify disease presentation and severity in allergic disorders. Primary atopic disorders (PADs) are a heterogenous group of single gene disorders that lead to significant atopic and allergic disease manifestations. However, a number of these monogenic diseases have variable penetrance suggesting that gene-gene and/or gene-environment interactions could modulate the clinical phenotype. Environmental factors such as diet, the microbiome at the epithelial-environment interface, the presence and/or extent of infection, and psychologic stress can alter disease phenotypic expression of allergic diseases, and PADs provide discrete contexts in which to understand these influences. We outline how gene-environment interactions likely contribute to a variable penetrance and expressivity in PADs. Dietary modifications of both macronutrients and/or micronutrients alter T-cell metabolism and may influence effector T-cell function. The mucosal microbiome may affect local inflammation and may remotely influence regulatory elements, while psychologic stress can affect mast cell and other allergic effector cell function. Understanding gene-environment interactions in PADs can hopefully provide a foundation for interrogating gene-environment interactions to common allergic disorders, and also present opportunities for personalized interventions based on the altered pathways and environmental influences in affected individuals.

Gut Microbiota Regulates Mincle Mediated Activation of Lung Dendritic Cells to Protect Against Mycobacterium tuberculosis

Gut microbial components serve as ligand for various pattern recognition receptors (PRRs) present on immune cells and thereby regulates host immunity. Dendritic cells (DCs) are highly specialized innate cells involved in immune response to Mycobacterium tuberculosis (Mtb) infection. The gut-lung axis is a potential therapeutic target in tuberculosis; however, understanding of the innate immune mechanism underlying the interaction of gut microbiota and lung still remains obscure. We investigated if antibiotics (Abx) induced gut dysbiosis is able to affect the activation of innate receptor, macrophage inducible C-type lectin (mincle) in lungs during Mtb infection. We found that dysbiosis reduced the lung mincle expression with a concomitant increase in Mtb survival. Further, Abx diminished the effector and memory T cell population, while elevating frequency of regulatory T cells (Tregs) in the lungs. Here, we show that dysbiotic mice exhibited low mincle expression on lung DCs. These DCs with impaired phenotype and functions had reduced ability to activate naïve CD4 T cells, and thus unable to restrict Mtb survival. In vivo administration of trehalose-6,6-dibehenate (TDB: mincle ligand) efficiently rescued this immune defect by enhancing lung DCs function and subsequent T cell response. Further, gut microbial profiling revealed augmentation of Lactobacillus upon mincle stimulation in microbiota depleted animals. Accordingly, supplementation with Lactobacillus restored mincle expression on lung DCs along with anti-Mtb response. Our data demonstrate that gut microbiota is crucial to maintain DC-dependent lung immune response against Mtb, mediated by mincle. Abx interrupt this process to induce impaired T cell-response and increased susceptibility to Mtb.

T cells loaded with magnetic nanoparticles are retained in peripheral lymph nodes by the application of a magnetic field

Background

T lymphocytes are highly dynamic elements of the immune system with a tightly regulated migration. T cell-based transfer therapies are promising therapeutic approaches which in vivo efficacy is often limited by the small proportion of administered cells that reaches the region of interest. Manipulating T cell localisation to improve specific targeting will increase the effectiveness of these therapies. Nanotechnology has been successfully used for localized release of drugs and biomolecules. In particular, magnetic nanoparticles (MNPs) loaded with biomolecules can be specifically targeted to a location by an external magnetic field (EMF). The present work studies whether MNP-loaded T cells could be targeted and retained in vitro and in vivo at a site of interest with an EMF.

Results

T cells were unable to internalize the different MNPs used in this study, which remained in close association with the cell membrane. T cells loaded with an appropriate MNP concentration were attracted to an EMF and retained in an in vitro capillary flow-system. MNP-loaded T cells were also magnetically retained in the lymph nodes after adoptive transfer in in vivo models. This enhanced in vivo retention was in part due to the EMF application and to a reduced circulating cell speed within the organ. This combined use of MNPs and EMFs did not alter T cell viability or function.

Conclusions

These studies reveal a promising approach to favour cell retention that could be implemented to improve cell-based therapy.

Electronic supplementary material

The online version of this article (10.1186/s12951-019-0440-z) contains supplementary material, which is available to authorized users.

Forced Expression of CXCL10 Prevents Liver Metastasis of Colon Carcinoma Cells by the Recruitment of Natural Killer Cells

CXC chemokine ligand 10 (CXCL10) is a CXC chemokine family protein that transmits signals by binding to its specific receptor, CXCR3. CXCL10 is also known as an interferon-γ-inducible chemokine involved in various biological phenomena, including chemotaxis of natural killer (NK) cells and cytotoxic T lymphocytes, that suppress tumor growth and inhibition of angiogenesis. In this study, we examined the effects of forced expression of CXCL10 in a murine colon carcinoma cell line (CT26) on growth and metastasis in syngeneic mice. We first established CT26 cells that were stably expressing murine CXCL10 (CT26/CXCL10) and compared their growth with their parental CT26 cells in vitro and in vivo. The in vitro growth of the CT26/CXCL10 and CT26 cells was comparable, whereas the in vivo growth of the CT26/CXCL10 cells in the skin was strongly suppressed. Liver metastasis of the CT26/CXCL10 cells was also significantly suppressed after intra-splenic implantation. Removal of NK cells by the administration of anti-asialo GM1 antibody canceled the suppression of subcutaneous growth and liver metastasis of CT26/CXCL10 cells. Immunofluorescence clearly showed that abundant NKp46-positive NK cells were recruited into the liver metastatic lesions of the CT26/CXCL10 cells, consistent with specific NK cell migration towards the culture supernatant from the CT26/CXCL10 cells in the chemotaxis assay using transwells. These findings indicate that CXCL10 prevents in vivo growth and metastasis of colon carcinoma cells by recruiting NK cells, suggesting that forced expression of CXCL10 in the colon tumors by gene delivery should lead to a favorable clinical outcome.

The TGFα-EGFR-Akt signaling axis plays a role in enhancing proinflammatory chemokines in triple-negative breast cancer cells

Triple-negative breast cancer (TNBC) is aggressive and typically has a poor prognosis. Chemokines have chemoattractant potential for cancer metastasis. Here, we investigated the chemokine signatures in BC subtypes and the underlying mechanisms that enhance proinflammatory chemokines in TNBC. Analysis from microarray dataset revealed that basal-like BC subtype including TNBC expressed dominantly proinflammatory chemokines, such as CXCL1 and 8, compared to non-TNBC. Chemokine PCR array confirmed the dominant chemokines in TNBC cells. To identify a driving factor for proinflammatory chemokines in TNBC cells, we determined the expression and signaling profiles of epidermal growth factor receptor (EGFR) family members. TNBC cells expressed higher levels of EGFR and phosphorylated Akt/Erk than non-TNBC cells. In addition, EGF further enhanced the proinflammatory chemokines in TNBC cells, including CXCL2. Knockdown of Akt reduced the CXCL2 promoter activity, while overexpression of Akt enhanced it. MK2206, an Akt inhibitor, reduced the CXCL2 promoter activity, while inhibition and knockdown of Erk did not reduce its activity. We found that transforming growth factor alpha (TGFα) could serve as a main ligand for EGFR to drive EGFR-mediated Akt activation in TNBC cells. MK2206 decreased TGFα promoter activity, while overexpression of Akt increased it. MK2206 also reduced TGFα release from TNBC cells. Moreover, MK2206 downregulated CXCL2 mRNA expression, while TGFα upregulated it. Taken together, the TGFα-EGFR-Akt signaling axis can play a role in enhancing proinflammatory chemokine expression in TNBC, subsequently contributing to the inflammatory burden that ultimately lead to cancer progression and a higher mortality rate among TNBC patients.

BH3 mimetics suppress CXCL12 expression in human malignant peripheral nerve sheath tumor cells

Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive, Schwann cell-derived neoplasms of the peripheral nervous system that have recently been shown to possess an autocrine CXCL12/CXCR4 signaling loop that promotes tumor cell proliferation and survival. Importantly, the CXCL12/CXCR4 signaling axis is driven by availability of the CXCL12 ligand rather than CXCR4 receptor levels alone. Therefore, pharmacological reduction of CXCL12 expression could be a potential chemotherapeutic target for patients with MPNSTs or other pathologies wherein the CXCL12/CXCR4 signaling axis is active. AT101 is a well-established BCL-2 homology domain 3 (BH3) mimetic that we recently demonstrated functions as an iron chelator and thus acts as a hypoxia mimetic. In this study, we found that AT101 significantly reduces CXCL12 mRNA and secreted protein in established human MPNST cell lines in vitro. This effect was recapitulated by other BH3 mimetics [ABT-737 (ABT), obatoclax (OBX) and sabutoclax (SBX)] but not by desferrioxamine (DFO), an iron chelator and known hypoxia mimetic. These data suggest that CXCL12 reduction is a function of AT101's BH3 mimetic property rather than its iron chelation ability. Additionally, this study investigates a potential mechanism of BH3 mimetic-mediated CXCL12 suppression: liberation of a negative CXCL12 transcriptional regulator, poly (ADP-Ribose) polymerase I (PARP1) from its physical interaction with BCL-2. These data suggest that clinically available BH3 mimetics might prove therapeutically useful at least in part by virtue of their ability to suppress CXCL12 expression.

In Situ Caging of Biomolecules in Graphene Hybrids for Light Modulated Bioactivity

Remote and noninvasive modulation of protein activity is essential for applications in biotechnology and medicine. Optical control has emerged as the most attractive approach owing to its high spatial and temporal resolutions; however, it is challenging to engineer light responsive proteins. In this work, a near-infrared (NIR) light-responsive graphene-silica-trypsin (GST) nanoreactor is developed for modulating the bioactivity of trypsin molecules. Biomolecules are spatially confined and protected in the rationally designed compartment architecture, which not only reduces the possible interference but also boosts the bioreaction efficiency. Upon NIR irradiation, the photothermal effect of the GST nanoreactor enables the ultrafast in situ heating for remote activation and tuning of the bioactivity. We apply the GST nanoreactor for remote and ultrafast proteolysis of proteins, which remarkably enhances the proteolysis efficiency and reduces the bioreaction time from the overnight of using free trypsin to seconds. We envision that this work not only provides a promising tool of ultrafast and remotely controllable proteolysis for in vivo proteomics in study of tissue microenvironment and other biomedical applications but also paves the way for exploring smart artificial nanoreactors in biomolecular modulation to gain insight in dynamic biological transformation.

A mini review on immune role of chemokines and its receptors in snakehead murrel Channa striatus

Chemokines are ubiquitous cytokine molecules involved in migration of cells during inflammation and normal physiological processes. Though the study on chemokines in mammalian species like humans have been extensively studied, characterization of chemokines in teleost fishes is still in the early stage. The present review provides an overview of chemokines and its receptors in a teleost fish, Channa striatus. C. striatus is an air breathing freshwater carnivore, which has enormous economic importance. This species is affected by an oomycete fungus, Aphanomyces invadans and a Gram negative bacteria Aeromonas hydrophila is known to cause secondary infection. These pathogens impose immune changes in the host organism, which in turn mounts several immune responses. Of these, the role of cytokines in the immune response is immense, due to their involvement in several activities of inflammation such as cell trafficking to the site of inflammation and antigen presentation. Given that importance, chemokines in fishes do have significant role in the immunological and other physiological functions of the organism, hence there is a need to understand the characteristics, activities and performace of these small molecules in details.

Role of G protein-coupled receptor kinase-6 in Escherichia coli lung infection model in mice

G protein-coupled receptor kinase-6 (GRK6) is a serine/threonine kinase that is important in inflammatory processes. In this study, we examined the role of GRK6 in Escherichia coli-induced lung infection and inflammation using GRK6 knockout (KO) and wild-type (WT) mice. Intratracheal instillation of E. coli significantly enhanced bacterial load in the bronchoalveolar lavage (BAL) of KO compared with WT mice. Reduced bacterial clearance in the KO mice was not due to an intrinsic defect in neutrophil phagocytosis or killing but as a result of reduced neutrophil numbers in the KO BAL. Interestingly, neutrophil numbers in the lung were increased in the KO compared with WT mice, suggesting a potential dysfunction in transepithelial migration of neutrophils from the lungs to the bronchoalveolar space. This effect was selective for lung tissue because peritoneal neutrophil numbers were similar between the two genotypes following peritoneal infection. Although neutrophil expression of CXCR2/CXCR3 was similar between WT and KO, IL-17A expression was higher in the KO compared with WT mice. These results suggest that enhanced neutrophil count in the KO lungs but reduced numbers in BAL are likely due to transepithelial migration defect and/or altered chemokines/cytokines. Together, our studies suggest a previously unrecognized and novel role for GRK6 in neutrophil migration specific to pulmonary tissue during bacterial infection.

The Th17 Lineage: From Barrier Surfaces Homeostasis to Autoimmunity, Cancer, and HIV-1 Pathogenesis

The T helper 17 (Th17) cells represent a subset of CD4+ T-cells with unique effector functions, developmental plasticity, and stem-cell features. Th17 cells bridge innate and adaptive immunity against fungal and bacterial infections at skin and mucosal barrier surfaces. Although Th17 cells have been extensively studied in the context of autoimmunity, their role in various other pathologies is underexplored and remains an area of open investigation. This review summarizes the history of Th17 cell discovery and the current knowledge relative to the beneficial role of Th17 cells in maintaining mucosal immunity homeostasis. We further discuss the concept of Th17 pathogenicity in the context of autoimmunity, cancer, and HIV infection, and we review the most recent discoveries on molecular mechanisms regulating HIV replication/persistence in pathogenic Th17 cells. Finally, we stress the need for novel fundamental research discovery-based Th17-specific therapeutic interventions to treat pathogenic conditions associated with Th17 abnormalities, including HIV infection.

IL-17-Secreting γδ T Cells Are Completely Dependent upon CCR6 for Homing to Inflamed Skin

mAbs that neutralize IL-17 or its receptor have proven efficacious in treating moderate-to-severe psoriasis, confirming IL-17 as an important driver of this disease. In mice, a rare population of T cells, γδT17 cells, appears to be a dominant source of IL-17 in experimental psoriasis. These cells traffic between lymph nodes and the skin, and are identified by their coexpression of the TCR variable regions γ4 and δ4. These cells are homologous to the Vγ9Vδ2 T cell population identified in human psoriatic plaques. In this study we report that a potent and specific small molecule antagonist of the CCR6 chemokine receptor, CCX2553, was efficacious in reducing multiple aspects of psoriasis in two different murine models of the disease. Administration of CCX2553 ameliorated skin inflammation in both the IL-23-induced ear swelling model and the topical imiquimod model, and significantly reduced the number of γδT17 cells in inflamed skin. γδT17 cells were greatly reduced in imiquimod-treated skin of CCR6^-/- mice, but adoptively transferred wild-type (CCR6^+/+) γδT17 cells homed normally to the skin of imiquimod-treated CCR6^-/- mice. Our data suggest that γδT17 cells are completely dependent on CCR6 for homing to psoriasiform skin. Thus, CCR6 may constitute a novel target for a mechanistically distinct therapeutic approach to treating psoriasis.

Cytokine expression profile in hospitalized children with herpes simplex virus-1 infection

Aim: We aim to demonstrate the cytokine expression profile of children with herpes simplex virus-1 (HSV-1) infection. Methods: One hundred eighty three children with acute encephalitis were enrolled in this study. Out of those with HSV-1, multiple cytokines were measured. Results: Cytokine analysis of 13 HSV-1-infected patients revealed that IL-8 and granulocyte macrophage colony stimulating factor accumulated at significantly higher levels than macrophage inflammatory protein-1β in the cerebrospinal fluid. Additionally, IFN-γ in serum and cerebrospinal fluid was positively correlated with course of illness, while IL-10 in cerebrospinal fluid was negatively correlated with course of illness. Conclusion: Granulocyte macrophage colony stimulating factor, IL-8, macrophage inflammatory protein-1β, IFN-γ and IL-10 are involved in the HSV-1 immune response and pathogenesis.

The Distribution of Activation Markers and Selectins on Peripheral T Lymphocytes in Preeclampsia

Introduction

Impaired maternal immune tolerance resulting in systemic inflammation plays a pivotal role in the pathogenesis of preeclampsia. Phenotypical changes of monocytes and neutrophil granulocytes have already been studied in preeclampsia, and some studies also included T lymphocyte activation markers; however, the results are controversial and a comprehensive analysis of activation markers is lacking. The characteristics of cellular adhesion molecules in preeclampsia are yet to be described.

Material and Methods

Peripheral blood samples of 18 preeclamptic patients and 20 healthy pregnant women in the third trimester were evaluated using flow cytometry to characterize the cell surface expression of T lymphocyte activation markers and selectins.

Results

We found an elevated ratio of HLA-DR and CD122-, CD62E-, and CD62L-expressing cells among the CD4+ T lymphocytes in PE in comparison to healthy pregnancy. No alterations were found in the prevalence of CD69-, CD25-, and CD62P-expressing lymphocytes and CD11c-expressing monocytes.

Conclusions

Our findings support the role of activated T lymphocytes and specific cell adhesion molecules in the pathogenesis of preeclampsia.

Chemokine receptors in allergic diseases

Under homeostatic conditions, as well as in various diseases, leukocyte migration is a crucial issue for the immune system that is mainly organized through the activation of bone marrow-derived cells in various tissues. Immune cell trafficking is orchestrated by a family of small proteins called chemokines. Leukocytes express cell-surface receptors that bind to chemokines and trigger transendothelial migration. Most allergic diseases, such as asthma, rhinitis, food allergies, and atopic dermatitis, are generally classified by the tissue rather than the type of inflammation, making the chemokine/chemokine receptor system a key point of the immune response. Moreover, because small antagonists can easily block such receptors, various molecules have been developed to suppress the recruitment of immune cells during allergic reactions, representing potential new drugs for allergies. We review the chemokines and chemokine receptors that are important in asthma, food allergies, and atopic dermatitis and their respectively developed antagonists.

Neuro-psychopharmacological perspective of Orphan receptors of Rhodopsin (class A) family of G protein-coupled receptors

BACKGROUND

In the central nervous system (CNS), G protein-coupled receptors (GPCRs) are the most fruitful targets for neuropsychopharmacological drug development. Rhodopsin (class A) is the most studied class of GPCR and includes orphan receptors for which the endogenous ligand is not known or is unclear. Characterization of orphan GPCRs has proven to be challenging, and the production pace of GPCR-based drugs has been incredibly slow.

OBJECTIVE

Determination of the functions of these receptors may provide unexpected insight into physiological and neuropathological processes. Advances in various methods and techniques to investigate orphan receptors including in situ hybridization and knockdown/knockout (KD/KO) showed extensive expression of these receptors in the mammalian brain and unmasked their physiological and neuropathological roles. Due to these rapid progress and development, orphan GPCRs are rising as a new and promising class of drug targets for neurodegenerative diseases and psychiatric disorders.

CONCLUSION

This review presents a neuropsychopharmacological perspective of 26 orphan receptors of rhodopsin (class A) family, namely GPR3, GPR6, GPR12, GPR17, GPR26, GPR35, GPR39, GPR48, GPR49, GPR50, GPR52, GPR55, GPR61, GPR62, GPR63, GPR68, GPR75, GPR78, GPR83, GPR84, GPR85, GPR88, GPR153, GPR162, GPR171, and TAAR6. We discussed the expression of these receptors in mammalian brain and their physiological roles. Furthermore, we have briefly highlighted their roles in neurodegenerative diseases and psychiatric disorders including Alzheimer's disease, Parkinson's disease, neuroinflammation, inflammatory pain, bipolar and schizophrenic disorders, epilepsy, anxiety, and depression.

Chemokine receptor 9 high-expression involved in the migration and invasion of the non-small-cell lung cancer cells

Background: Metastasis is responsible for most cancer-related death, and the metastatic spread of neoplastic cells may be related to the ability of migration and invasion. Chemokine receptor 9 (CCR9) plays an important role in cutaneous melanoma and prostate cancer cells migration and invasion.

Objective: Investigate the specific role of the chemokine-ligand (CCR9-CCL25) axis in the development of nonsmall cell lung cancer (NSCLC) metastasis.

Methods: Semi-quantitative reverse transcriptase-PCR, western-blot, flow cytometry, migration, and invasion assays were used to examine the function of CCR9 in the NSCLC cells.

Results: CCR9 was highly expressed in NSCLC patient cancer tissue. In addition, in vitro migration and invasion studies on human bronchial epithelial cells of the BEAS-2B and human squamous lung cancer cell lines NCI-H157 showed that migration in response to the CCL25 was inhibited by CCR9 antibody.

Conclusion: CCR9 might play an important role in the migration and invasion of the NSCLC cells.

Chemokines in Oral Inflammatory Diseases: Apical Periodontitis and Periodontal Disease

The inflammatory oral diseases are characterized by the persistent migration of polymorphonuclear leukocytes, monocytes, lymphocytes, plasma and mast cells, and osteoblasts and osteoclasts. In the last decade, there has been a great interest in the mediators responsible for the selective recruitment and activation of these cell types at inflammatory sites. Of these mediators, the chemokines have received particular attention in recent years. Chemokine messages are decoded by specific receptors that initiate signal transduction events, leading to a multitude of cellular responses, including chemotaxis and activation of inflammatory and bone cells. However, little is known about their role in the pathogenesis of inflammatory oral diseases. The purpose of this review is to summarize the findings regarding the role of chemokines in periapical and periodontal tissue inflammation, and the integration, into experimental models, of the information about the role of chemokines in human diseases.

Development of CXCR4 modulators by virtual HTS of a novel amide-sulfamide compound library

CXCR4 plays a crucial role in recruitment of inflammatory cells to inflammation sites at the beginning of the disease process. Modulating CXCR4 functions presents a new avenue for anti-inflammatory strategies. However, using CXCR4 antagonists for a long term usage presents potential serious side effect due to their stem cell mobilizing property. We have been developing partial CXCR4 antagonists without such property. A new computer-aided drug design program, the FRESH workflow, was used for anti-CXCR4 lead compound discovery and optimization, which coupled both compound library building and CXCR4 docking screens in one campaign. Based on the designed parent framework, 30 prioritized amide-sulfamide structures were obtained after systemic filtering and docking screening. Twelve compounds were prepared from the top-30 list. Most synthesized compounds exhibited good to excellent binding affinity to CXCR4. Compounds Ig and Im demonstrated notable in vivo suppressive activity against xylene-induced mouse ear inflammation (with 56% and 54% inhibition). Western blot analyses revealed that Ig significantly blocked CXCR4/CXCL12-mediated phosphorylation of Akt. Moreover, Ig attenuated the amount of TNF-α secreted by pathogenic E. coli-infected macrophages. More importantly, Ig had no observable cytotoxicity. Our results demonstrated that FRESH virtual high throughput screening program of targeted chemical class could successfully find potent lead compounds, and the amide-sulfamide pharmacophore was a novel and effective framework blocking CXCR4 function.

Tissue Microenvironments in the Nasal Epithelium of Rainbow Trout (Oncorhynchus mykiss) Define Two Distinct CD8α+ Cell Populations and Establish Regional Immunity

Mucosal surfaces require balancing different physiological roles and immune functions. To effectively achieve multifunctionality, mucosal epithelia have evolved unique microenvironments that create unique regional immune responses without impairing other normal physiological functions. Whereas examples of regional immunity are known in other mucosal epithelia, to date, no immune microenvironments have been described in the nasal mucosa, a site where the complex functions of olfaction and immunity need to be orchestrated. In this study we identified the presence of CD8α⁺ cells in the rainbow trout (Oncorhynchus mykiss) nasal epithelium. Nasal CD8α⁺ cells display a distinct phenotype suggestive of CD8⁺ T cells with high integrin β₂ expression. Importantly, nasal CD8α⁺ cells are located in clusters at the mucosal tip of each olfactory lamella but scattered in the neuroepithelial region. The grouping of CD8α⁺ cells may be explained by the greater expression of CCL19, ICAM-1, and VCAM-1 in the mucosal tip compared with the neuroepithelium. Whereas viral Ag uptake occurred via both tip and lateral routes, tip-resident MHC class II⁺ cells are located significantly closer to the lumen of the nasal cavity than are their neuroepithelial counterparts, therefore having quicker access to invading pathogens. Our studies reveal compartmentalized mucosal immune responses within the nasal mucosa of a vertebrate species, a strategy that likely optimizes local immune responses while protecting olfactory sensory functions.

The chemotactic interaction between CCL21 and its receptor, CCR7, facilitates the progression of pancreatic cancer via induction of angiogenesis and lymphangiogenesis

BACKGROUND

In this study, we report the influence of CCL21 and its receptor, CCR7, on the progression of pancreatic cancer and illuminates the correlation between the CCL21/CCR7 axis and the angiogenesis and lymphangiogenesis of pancreatic adenocarcinoma (PAC).

METHODS

A total of 30 patients with pancreatic cancer was involved in the current study. The expression of CCL21 and CCR7 in cancerous tissues, paracancerous tissues and normal pancreas were investigated using real-time PCR, Western blot and immunohistochemistry, respectively. In addition, we assessed microvessel density (MVD) and microlymphatic vessel density (MLVD) in tumor tissues using immunohistochemistry.

RESULTS

Compared to paracancerous tissues and normal pancreas, CCL21 expression in cancerous tissues was detected at a significantly low level. In contrast, the CCR7 expression was considerably higher in cancerous tissues than in normal pancreas and paracancerous tissues. Additionally, a significant correlation between the expression pattern of the CCL21/CCR7 axis and clinicopathological features, such as lymph node metastasis, was identified. Furthermore, we found that CCL21 expression was significantly associated with MVD but not significantly associated with MLVD, while CCR7 expression was significantly associated with MLVD but not significantly associated with MVD.

CONCLUSIONS

The chemotactic interaction between CCR7 and its ligand, CCL21, may be a critical event during progression in pancreatic cancer, and its underlying mechanism may be induction of angiogenesis and lymphangiogenesis regulated by this chemotactic interaction.

Identification of IL-23p19 as an endothelial proinflammatory peptide that promotes gp130-STAT3 signaling

Interleukin-23 (IL-23), a heterodimeric cytokine composed of the unique p19 peptide (IL-23p19) and a peptide called IL-12p40, which is shared with IL-12, is implicated in Crohn's disease, rheumatoid arthritis, psoriasis, and other immune-mediated inflammatory diseases. Endothelial cells produce the IL-23p19 peptide in the absence of the IL-12p40 chain and thus do not make heterodimeric IL-23. We found that intercellular IL-23p19 increased the cell surface abundances of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells, which enhanced the attachment of leukocytes and increased their transendothelial migration. Intracellular p19 associated with the cytokine receptor subunit gp130 and stimulated the gp130-dependent activation of signal transducer and activator of transcription 3 (STAT3) signaling. Proinflammatory factors promoted the generation of IL-23p19 in endothelial cells. The adventitial capillaries of inflamed temporal arteries in patients with giant-cell arteritis (GCA) had endothelial p19 protein associated with gp130, but did not contain the IL-12p40 chain. Because adventitial capillaries are essential for the entry of inflammatory cells into arterial walls, these data suggest that p19 may contribute to GCA disease and could represent a therapeutic target. Our results provide evidence that IL-23p19 is a previously unrecognized endothelial proinflammatory peptide that promotes leukocyte transendothelial migration, advancing our current understanding of the complexities of inflammatory responses.

CXCR4 antagonist AMD3100 ameliorates thyroid damage in autoimmune thyroiditis in NOD.H‑2h⁴ mice

CXC chemokine ligand 12 (CXCL12) and its receptor, CXC chemokine receptor 4 (CXCR4), are upregulated in mice with autoimmune thyroid diseases. However, whether this interaction is involved in the pathophysiology of autoimmune thyroiditis (AIT) remains to be elucidated. In the present study, the effects of the CXCR4 antagonist, AMD3100, in an iodine‑induced autoimmune thyroiditis model were investigated. NOD.H‑2h4 mice were randomly separated into a control, AIT and AIT+AMD3100 groups. The mice were fed with 0.05% sodium iodide water for 8 weeks to induce AIT. The AMD3100‑treated mice were administered with the CXCR4 antagonist at a dose of 10 mg/kg intraperitoneally three times a week during the experimental period. The percentages of CD19+interleukin (IL)10+ B cells and CD4+IL10+ T cells, and the mRNA expression levels of IL10 in the splenocytes were reduced in the AIT group, compared with the control group, however, they increased following AMD3100 treatment, compared with the untreated AIT group. The percentages of CD4+ T cells, CD8+ T cells, CD19+ B cells and CD8+ interferon (IFN)γ+ T cells, and the mRNA expression levels of IFNγ increased in the AIT group, compared with the control group, however, these were reduced in the AMD3100 group, compared with the AIT group. The AMD3100‑treated mice also had lower serum thyroglobulin antibody titers and reduced lymphocytic infiltration in the thyroid, compared with the untreated AIT mice. These results suggested that inhibition of this chemokine axis may offer potential as a therapeutic target for the treatment of AIT.

Modulation of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis by Helicobacter pylori in immune pathogenesis of gastric mucosal damage

Helicobacter pylori infection is associated with chronic gastritis, peptic ulcer, gastric carcinoma, and gastric mucosa-associated lymphoid tissue lymphomas. Apoptosis induced by microbial infections is implicated in the pathogenesis of H. pylori infection. Enhanced gastric epithelial cell apoptosis during H. pylori infection was suggested to play an important role in the pathogenesis of chronic gastritis and gastric pathology. In addition to directly triggering apoptosis, H. pylori induces sensitivity to tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-mediated apoptosis in gastric epithelial cells. Human gastric epithelial cells sensitized to H. pylori confer susceptibility to TRAIL-mediated apoptosis via modulation of death-receptor signaling. The induction of TRAIL sensitivity by H. pylori is dependent upon the activation of caspase-8 and its downstream pathway. H. pylori induces caspase-8 activation via enhanced assembly of the TRAIL death-inducing signaling complex through downregulation of cellular FLICE-inhibitory protein. Moreover, H. pylori infection induces infiltration of T lymphocytes and triggers inflammation to augment apoptosis. In H. pylori infection, significant increases in CCR6⁺ CD3⁺ T cell infiltration in the gastric mucosa was observed, and the CCR6 ligand, CCL20 chemokine, was selectively expressed in inflamed gastric tissues. These mechanisms initiate chemokine-mediated T lymphocyte trafficking into inflamed epithelium and induce mucosal injury during Helicobacter infection. This article will review recent findings on the interactions of H. pylori with host-epithelial signaling pathways and events involved in the initiation of gastric pathology, including gastric inflammation and mucosal damage.