Expression Of CC Chemokines Research Articles

Differential regulation of CC chemokine ligand 2 and CXCL8 by antifungal agent nystatin in macrophages

The polyene antifungal antibiotic nystatin can interact with cholesterol, thereby altering the composition of the plasma membrane in eukaryotic cells. We investigated whether nystatin influences responses to the infection by inducing expression of chemokines. THP-1 macrophages rarely expressed CC chemokine ligand 2 (CCL2) and CXCL8. However, nystatin dose-dependently increased CCL2 and CXCL8 expression at the mRNA and protein levels. To understand the molecular mechanisms of the antifungal agent, we identified cellular factors activated by nystatin and those involved in nystatin-induced upregulation of CCL2 and CXCL8. Treatment with nystatin resulted in enhanced phosphorylation of Akt, ERK1/2, p38 MAPK, and JNK. Treatment with cholesterol, LY294002, Akt inhibitor IV, U0126, and SP6001250 resulted in abrogation or significant attenuation of nystatin-induced CCL2 expression. Nystatin-mediated CXCL8 expression was attenuated in the presence of Akt inhibitor IV and SP6001250. These results indicate that exposure of human macrophages to nystatin can lead to differential regulation of CCL2 and CXCL8 via the activation of multiple cellular kinases. We propose that upregulation of CCL2 and CXCL8 contributes to pharmacological effects of nystatin.

A COMPARATIVE STUDY BETWEEN RANAVIRUS AND MEGALOCYTIVIRUS INFECTIONS IN ORANGE-SPOTTED GROUPER (Epienphelus coioides)

Piscine iridoviruses infect a wide variety of fish and are classified into three genera: Lymphocystivirus, Ranavirus and Megalocytivirus. Lymphocystiviruses cause non-fatal, dermal infections, while ranaviruses and megalocytiviruses produce devastating, systemic infections with mortality reaching up to 100%. Although both ranaviruses and megalocytiviruses cause fatal systemic infections, they induce different pathology. In Taiwan, both ranaviruses and megalocytiviruses have caused serious epidemics in several mariculture fish species, including groupers. In this study, we infected the orange-spotted grouper (Epinephelus coioides) with either a megalocytivirus (TGIV, grouper iridovirus of Taiwan) or a ranavirus (GIV, grouper iridovirus), and then the two iridoviruses were investigated and compared in respect of their target organs, virulence, and effects on the expression of several immune-related genes in the spleen and head kidney. By measuring cumulative mortality rate, GIV was shown to have higher virulence than TGIV. By PCR, we found that TGIV mainly infected the spleen, head kidney, kidney, heart and gill, while GIV mainly infected the spleen and intestine. The assayed immune genes were hemoglobin subunit-β-2 (Hb), CC chemokine 19, Toll-like receptor 9 isoform A and B (TLR9-A and B) and Mx (myxovirus resistance). By real-time RT-PCR, we found that of the assayed genes, the expression of CC chemokine 19 was strongly induced in spleen by both viruses, whereas the expression of Mx were strongly induced by both viruses in both organs and the expression of Hb gene was induced only by TGIV in head kidney.

Effects of Repeated Lipopolysaccharide Stimulation on the Development of Antigen-presenting Cells and T Cells Pool in Hen Vagina

The aim of this study was to determine how the mucosal immunity mediated by T cells is developed in the vagina. Antigen-presenting cells and T cells play important roles in the early process of host defense. Mature T cells and immature dendritic cells expressing CC chemokine receptor (CCR) 6. In contrast, immature T cells and mature dendritic cells express CCR7. It was examined whether repeated antigen stimulation is effective for development of the pool of antigen-presenting cells and T cells in the vagina. White Leghorn hens were intravaginally injected 1 (single injection group) or 5 times (repeated injection group) in 10 days with saline (control) or lipopolysaccharide (LPS). The vagina was collected 1 day after the final injection. Frozen sections of them were immunostained for CD4+, CD8+, TCRγδ+ T cells and major histocompatibility complex (MHC) class II+ cells. Expressions of CCR6, CCR7 and MHC class II were analyzed by quantitative RT-PCR. The frequency of CD4+, CD8+, TCRγδ+ T cells were significantly increased in LPS-repeated injection group, however that of MHC class II+ cells was not changed significantly. The expression of CCR6 was significantly upregulated in LPS-repeated injection group, however, the expression of CCR7 and MHC class II was not affected. The densities of the each T cell subset and MHC class II+ cells, as well as expressions of chemokine receptor, MHC class II were not affected by single LPS injection or saline injection. These results suggest that the repeated antigen stimulation may not affect antigen-presenting ability by antigen-presenting cells, whereas it may lead influx of T cell subsets in the vagina. These accumulated T cells pool may contribute to form prequiescence of host immunity in the vaginal mucosa.

Toll-Like Receptor 4 in Experimental Kidney Transplantation: Early Mediator of Endogenous Danger Signals

The role of toll-like receptors (TLRs) has been described in the pathogenesis of renal ischemia/reperfusion injury, but data on the expression and function of TLR4 during renal allograft damage are still scarce. We analyzed the expression of TLR4 in an experimental rat model 6 and 28 days after allogeneic kidney transplantation in comparison to control rats and rats after syngeneic transplantation. On day 6, a significant induction in TLR4 expression – restricted to the glomerular compartment – was found in acute rejecting allografts only. TLR4 expression strongly correlated with renal function, and TLR4 induction was accompanied by a significant increase in CC chemokine expression within the graft as well as in urinary CC chemokine excretion. TLR4 induction may be caused by an influx of macrophages as well as TLR4-expressing intrinsic renal cells. Fibrinogen deposition in renal allografts correlated with renal TLR4 expression and may act as a potent stimulator of chemokine release via TLR4 activation. This study provides, for the first time, data about the precise intrarenal localization and TLR4 induction after experimental kidney transplantation. It supports the hypothesis that local TLR4 activation by endogenous ligands may be one pathological link from unspecific primary allograft damage to subsequent chemokine release, infiltration and activation of immune cells leading to deterioration of renal function and induction of renal fibrosis.

Salivary basic proline-rich proteins are elevated in HIV-exposed seronegative men who have sex with men

Innate mucosal factors are associated with protection in HIV-exposed seronegative (HESN) individuals, but studies of MSM have been very limited. We performed proteomic analysis of saliva from a cohort of HESN MSM who have regular unprotected oral receptive intercourse with their HIV-infected partner. Saliva samples from HESN (n = 25) and non-exposed male controls (n = 22) were analyzed by 2D-LC mass spectrometry. An overexpressed innate protein factor was further characterized by immunoblot, and compared with CC-chemokine expression, HIV-neutralizing activity, clinical factors, and sexual behavior. Of 337 total proteins, seven were identified as differentially abundant in the HESN group. The five overabundant proteins (Basic salivary proline-rich proteins (bPRP) 2 and 3, Histatin-3, Lysozyme C, and SLPI) have known antimicrobial activity. bPRP2 showed the highest overabundance (>six-fold) in HESN individuals compared with controls (P = 0.009), including multiple isoforms. Salivary bPRP2 correlated with CC-chemokine levels in HESN individuals including RANTES (P = 0.02), MIP-1-alpha (P = 0.01), MIP-1-beta (P = 0.0002), MCP-1 (P = 0.005) and Eotaxin (P = 0.003) but not with frequency of HIV neutralizing activity, oral sexual practices, or viral load of the sexual partner. This study identifies salivary bPRP2 as a novel soluble factor elevated in the oral compartment of HIV-exposed MSM.

CD56+ T cells inhibit HIV-1 infection of macrophages

CD56+ T cells, the crucial component of the host innate immune system, play an important role in defense against viral infections. We investigated the noncytolytic anti-HIV-1 activity of primary CD56+ T cells. SNs collected from CD56+ T cell cultures inhibited HIV-1 infection and replication. This CD56+ T SN-mediated anti-HIV-1 activity was broad-spectrum, as CD56+ T SNs could inhibit infections by laboratory-adapted and clinical strains of HIV-1. The antibody to IFN-γ could partially block the CD56+ T SN-mediated anti-HIV effect. Investigation of mechanism(s) of the CD56+ T cell action on HIV-1 showed that although CD56+ T SN had little effect on HIV-1 entry coreceptor CCR5 expression, CD56+ T SN induced the expression of CC-chemokines, the ligands for CCR5. The antibodies to CC-chemokines also significantly blocked CD56+ T SN-mediated anti-HIV activity. Furthermore, CD56+ T SN up-regulated the expression of STAT-1/-2 and enhanced the expression of IRF1, -3, -7, and -9, resulting in the induction of endogenous IFN-α/β expression in macrophages. Moreover, CD56+ T SN up-regulated intracellular expression of APOBEC3G/3F, the recently identified HIV-1 restriction factors. These findings provide compelling evidence that CD56+ T cells may have a critical role in innate immunity against HIV-1 infection.

Regulated chemokine gene expression in mouse mesothelioma and mesothelial cells: TNF-α upregulates both CC and CXC chemokine genes

Many cancers express an array of chemokines which have the capacity to modulate the nature and function of intratumoural leukocyte infiltrates. In malignant mesothelioma (MM) neither the chemokine signalling networks nor their regulation have been investigated despite the prominence of leucocytic infiltrates in both clinical and experimental tumours. In this study, we examined constitutive and cytokine-regulated expression of CC and CXC chemokine genes in mesothelioma and mesothelial cell cultures derived from two different mouse strains (BALB/C and CBA/CaH). In mouse MM and mesothelial cells MCP-1/JE, GRO-α/KC and RANTES were expressed whereas MIP-1α and MIP-2 were infrequently expressed. Comparison of basal chemokine expression showed that GRO-α/KC mRNA was overexpressed in the malignant cells whereas MCP-1 gene expression and release was downregulated. Treatment of mesothelioma cells with IL-4, IFN-γ or TNF-α revealed that chemokine genes could be more responsive to cytokines in the malignant compared to their mesothelial cells. TNF-α was consistently the most potent positive regulator of both CC and CXC chemokine expression and MCP-1 release. The present study for the first time provides a mechanistic insight into the differential regulation of chemokine expression in malignant mesothelioma cells and has implications for mesothelial chemokine signalling in mouse models.

Laquinimod Restricts Inflammatory Gene Expression in a Human Model of Reactive Astrogliosis (P02.111)

Objective: Laquinimod is an orally administered CNS-active immunomodulator currently in phase III clinical trials for therapy of relapsing remitting multiple sclerosis (RRMS). Data show that RRMS patients show beneficial effects of laquinimod 0.6mg on clinical disease activity as evidenced by slowing of the progression of disability, reducing the rate of MRI-measured brain volume loss, and reducing relapse rate. The current work examines the mechanisms underlying these effects. Background Laquinimod crosses the blood-brain barrier and enters the CNS, thus in addition to peripheral effects it may act directly on CNS-resident lineages including oligodendrocytes, microglia and astrocytes. Increasing evidence implicates reactive astrocytes as critical regulators of CNS inflammation and repair in MS. Design/Methods: Here, we report that laquinimod profoundly impacts proinflammatory gene expression in a human in vitro model of reactive astrogliosis. Results: Interleukin-1beta (IL-1β) is implicated in lesion pathogenesis in RRMS, and in primary human astrocyte cultures it strongly induced inflammatory factors including cytokines, chemokines and reactive nitrogen species. Importantly, at therapeutic concentrations, laquinimod abrogated IL-1β-induced induction of cytokines including tumor necrosis factor-α (TNFα) and IL-6, and inducible nitric oxide synthase. Laquinimod also differentially regulated IL-1β-induced expression of CXC and CC chemokines, suggesting that it acts as an immunomodulator rather than an immunosuppressant in astrocyte cultures. IL-1β exerts its effects via the transcription factor NF-κB, and suggesting mechanism, laquinimod pretreatment of human astrocytes downregulated NF-κB activation. Conclusions: Collectively, these data reveal laquinimod as a regulator of the proinflammatory phenotype in a human model of reactive astrogliosis, and suggest that it may act centrally on resident CNS cells to restrict pathology in MS lesions. Supported by: A research grant from Teva Pharmaceuticals. Disclosure: Dr. Pham has nothing to disclose. Dr. Zhang has nothing to disclose. Dr. Hayardeny Nisimov has nothing to disclose. Dr. John has received personal compensation for activities with EMD Serono, Teva Neuroscience, and Biogen Idec. Dr. John has received research support from Teva Neuroscience, and Vaccinex Inc.

Inhibitory effects of melatonin on the lipopolysaccharide‐induced CC chemokine expression in BV2 murine microglial cells are mediated by suppression of Akt‐induced NF‐κB and STAT/GAS activity

Melatonin influences sleep and circadian rhythm, and it has anti-inflammatory functions. However, the mechanism of its anti-inflammatory roles is not well understood. In our studies, we show that melatonin blocked lipopolysaccharide (LPS)-induced CCL2 (monocyte chemotactic protein-1; MCP-1), CCL5 (Regulated upon Activation, Normal T-cell Expressed, and Secreted), and CCL9 (macrophage inflammatory protein-1γ) chemokine mRNA expression in BV2 murine microglial cells. Melatonin markedly inhibited LPS-induced Akt phosphorylation and NF-κB activation. Furthermore, melatonin inhibited LPS-induced STAT1/3 phosphorylation and interferon-gamma activated sequence (GAS)-driven transcriptional activity. Interestingly, these effects were not associated with reactive oxygen species scavenging effects of melatonin or melatonin receptor signal pathways. Taken together, our results suggested that melatonin has anti-inflammatory functions through down-regulation of chemokine expression by inhibition of NF-κB and STAT/GAS activation in LPS-stimulated BV2 murine microglial cell line.

Innate defense regulator peptide synergizes with CpG ODN for enhanced innate intestinal immune responses in neonate piglets

The in vivo immunoadjuvant effects of the combination of CpG oligodeoxynucleotide (CpG ODN) and innate defense-regulator peptides (IDRs) have been studied in mice. However, little is known about the efficacy of these molecules in stimulating the innate intestinal immune system in neonatal piglets. In this study, we observed that intranasal (IN) administration of CpG-IDR (peptide HH2 (VQLRIRVAVIRA)) complex significantly increased intestinal mRNA expression of Th1 cytokines, CC chemokines and CXC chemokines when compared to HH2 and CpG ODN alone. Also an obvious cellular infiltration was observed in the intestine of CpG–HH2-treated neonatal piglets, which was associated with increased protection against Enterotoxigenic Escherichia coli (ETEC). Moreover, we showed that pro-inflammatory cytokine TNF-α was inhibited when CpG ODN combined with HH2. This was the first report that deciphered the role played by CpG–HH2 complex in the intestine of neonatal piglets. This work clearly demonstrated that efficiency of the IN route inducing intestinal responses in neonatal piglets might be taken into consideration for further vaccine development against neonatal intestinal diseases.

Serum Levels of CC Chemokine Receptor 4 and CXC Chemokine Receptor 3 Ligands in CD8+ Sézary Syndrome

© 2012 The Authors. doi: 10.2340/00015555-1270 Journal Compilation © 2012 Acta Dermato-Venereologica. ISSN 0001-5555 Sezary syndrome is an erythrodermic cutaneous T-cell lymphoma with haematological evidence of leukemic involvement, which is typically characterized by a monoclonal proliferation of atypical CD4+CD45RO+ lymphocytes (Sezary cells). We report here a case of CD8+ Sezary syndrome that was treated successfully with methotrexate. Sezary cells were CD3+, CD4–, CD8+, CD45RO+. They also expressed CC chemokine receptor 4 and 10, but not CXC chemokine receptor 3. The number of Sezary cells and serum levels of soluble IL-2 receptor were positively correlated with serum levels of CC chemokine ligand 17, 22 and 27, whereas they were negatively correlated with serum levels of CXC chemokine ligand 10.

Prevention of Idiopathic Pneumonia Syndrome by Intra-Bone Marrow Injection of Donor Cells

Abstract 1902Several clinical and experimental studies have reported that a recently developed intra-bone marrow (IBM) stem cell transplantation (SCT) technique gives high rates of engraftment and is associated with a low incidence of acute graft-versus-host disease (GVHD). Idiopathic pneumonia syndrome (IPS) is a significant cause of mortality and remains a major obstacle after allogeneic SCT. In the present study, the extent of IPS after IBM-SCT was compared with that after conventional intravenous SCT (IV-SCT) using a lethally irradiated B6(H-2b) into F1 (H-2b/d) mouse IPS model.Compared with IV-SCT, IBM-SCT significantly improved the clinical GVHD score and reduced total and CD3+ T cell numbers in bronchoalveolar lavage fluid (9.6± 3.5 vs. 21.3 ± 0.5 x104/ml; p < 0.05). Histopathological examination of lung tissue at 6 weeks post-SCT showed significantly reduced IPS pathology in mice that underwent IBM-SCT. To explore the mechanisms of the reduction in IPS pathology in mice that underwent IBM-SCT, we monitored the in vivo distributions of infused donor cells and compared them between mice that underwent IBM-SCT versus IV-SCT. Recipient mice were imaged at different time points (1, 2, 3, and 6 h, and 1, 2, 3, and 5 days), using a lethally irradiated luciferase-expressing transgenic FVB/N (FVB/N luc+)(H-2q) into BALB/c (H-2d) mouse model. In vivo bioluminescence imaging (BLI) analysis revealed that the majority of injected donor cells were trapped in the lung 1 h after IV-SCT. In contrast, almost all donor cells were localized in the injected limbs 1 h after IBM-SCT, and significantly fewer cells had reached the lung (3.1± 0.7 vs. 16.7± 1.1 x105 photons/sec/animal, IBM-SCT vs. IV-SCT, p < 0.01; Figure). After syngeneic (FVB/N luc+ into FVB/N) SCT, the majority of the injected cells were also trapped in the lung 1 h after IV-SCT, and a similar difference was observed in donor cell distribution in the lung after IV-SCT versus IBM-SCT (2.4± 0.6 vs. 11.6± 1.3 x105 photons/sec/animal; p < 0.01). These results suggest that initial cell localization to the lung is dependent on the SCT method. At 2 days post-SCT, we examined the profiles of chemokines produced locally in the lung (CCL2, CCL3, CXCL1, CCL5, and CCL8). The mRNA expression of CC chemokines, especially CCL2, was more strongly induced in the lung after allogeneic IV-SCT than after allogeneic IBM-SCT (0.098 ± 0.020 vs. 0.020 ± 0.003 units/GAPDH mRNA; p < 0.05). A similar difference was observed between mice that underwent syngeneic IV-SCT and syngeneic IBM-SCT, suggesting that increases in chemokine levels in the lung early post-SCT are also dependent on the SCT method. At 5 days post-syngeneic SCT, BLI analysis revealed that no difference was observed in donor cell distribution in the lung after IV-SCT versus IBM-SCT (4.8± 1.1 vs. 4.6± 2.5 x107 photons/sec/animal; p =0.94). On the other hand, the BLI signals dramatically increased in the lungs of mice that had undergone allogeneic IV-SCT after day 2 post-SCT and there was a significant difference in the BLI signals between IV-SCT and IBM-SCT mice at 5 days post-SCT (50.9± 6.6 vs. 16.0± 6.2×107 photons/sec/animal; p < 0.05). These results suggest that increases in chemokine levels in the lung at day 2 post-SCT lead to increases in the allogeneic response in the lung.In summary, we have shown that the initial localization of donor cells to the lung and increases in lung chemokine levels are dependent on the SCT method. The targeting of donor cell trafficking to the lung may be a promising strategy for preventing IPS, and IBM-SCT may reduce IPS after allogeneic SCT. [Display omitted] Disclosures:No relevant conflicts of interest to declare.

Recombinant Human T-Cell Leukemia Virus Types 1 and 2 Tax Proteins Induce High Levels of CC-Chemokines and Downregulate CCR5 in Human Peripheral Blood Mononuclear Cells

Human T-cell leukemia viruses types 1 (HTLV-1) and 2 (HTLV-2) produce key transcriptional regulatory gene products, known as Tax1 and Tax2, respectively. Tax1 and Tax2 transactivate multiple host genes involved in cellular immune responses within the cellular microenvironment, including induction of genes encoding expression of CC-chemokines. It is speculated that HTLV Tax proteins may act as immune modulators. In this study, recombinant Tax1 and Tax2 proteins were tested for their effects on the viability of cultured peripheral blood mononuclear cells (PBMCs), and their ability to induce expression of CC-chemokines and to downregulate the level of CCR5 expression in PBMCs. PBMCs obtained from uninfected donors were cultured in a range of Tax1 and Tax2 concentrations (10-100 pM), and supernatant fluids were harvested at multiple time points for quantitative determinations of MIP-1α/CCL3, MIP-1β/CCL4, and RANTES/CCL5. Treatment of PBMCs with Tax1 and Tax2 proteins (100 pM) resulted in a significant increase in viability over a 7-d period compared to controls (p<0.01). Both Tax1 and Tax2 induced high levels of all three CC-chemokines over the dosing range compared to mock-treated controls (p<0.05). The gated population of lymphocytes treated with Tax2, as well as lymphocytes from HTLV-2-infected donors, showed a significantly lower percentage of CCR5-positive cells compared to those of uninfected donors and from mock-treated lymphocytes, respectively (p<0.05). These results suggest that Tax1 and Tax2 could promote innate immunity in the extracellular environment during HTLV-1 and HTLV-2 infections via CC-chemokine ligands and receptors.

Recruitment of CCR6-Expressing Th17 Cells by CCL 20 Secreted from IL-1β-, TNF-α-, and IL-17A-Stimulated Endometriotic Stromal Cells

In a novel paradigm of T cell differentiation, type 17 T helper (Th17) cells may play a significant role in endometriosis, a chronic inflammatory disease. However, the mechanism regulating the accumulation of Th17 cells in endometriotic tissues remains unknown. We hypothesized that Th17 cells migrate to endometriotic tissues through an interaction of the chemokine CC chemokine ligand (CCL)20 and its receptor CCR6. Using endometriotic tissues from women with endometriosis, we demonstrated, by flow cytometry, that Th17 cells in endometriotic tissues express CC chemokine receptor (CCR)6. Immunohistochemistry also revealed that CCL20 was expressed in the epithelial cells and stromal cells beneath the epithelium of endometriotic tissues. CCR6+ cells were small and round and scattered in the stroma in which abundant CCL20+ cells were detected. CCL20 caused selective migration of Th17 cells in the peripheral blood in a migration assay. IL-1β, TNF-α, and IL-17A increased the secretion of CCL20 in cultured endometriotic stromal cells. Inhibitors of p38- and p42/44-MAPKs, and stress-activated protein kinase/c-Jun kinase suppressed the secretion of CCL20 increased by IL-1β, TNF-α, and IL-17A. This suggests that the CCL20/CCR6 system is involved in the migration of Th17 cells to endometriotic tissues and that proinflammatory cytokines contribute to the development of endometriosis via up-regulation of CCL20 secretion from endometriotic stromal cells.

CCR9 interactions support ovarian cancer cell survival and resistance to cisplatin-induced apoptosis in a PI3K-dependent and FAK-independent fashion

BackgroundCisplatin is more often used to treat ovarian cancer (OvCa), which provides modest survival advantage primarily due to chemo-resistance and up regulated anti-apoptotic machineries in OvCa cells. Therefore, targeting the mechanisms responsible for cisplatin resistance in OvCa cell may improve therapeutic outcomes. We have shown that ovarian cancer cells express CC chemokine receptor-9 (CCR9). Others have also shown that CCL25, the only natural ligand for CCR9, up regulates anti-apoptotic proteins in immature T lymphocytes. Hence, it is plausible that CCR9-mediated cell signals might be involved in OvCa cell survival and inhibition of cisplatin-induced apoptosis. In this study, we investigated the potential role and molecular mechanisms of CCR9-mediated inhibition of cisplatin-induced apoptosis in OvCa cells.MethodsCell proliferation, vibrant apoptosis, and TUNEL assays were performed with or without cisplatin treatment in presence or absence of CCL25 to determine the role of the CCR9-CCL25 axis in cisplatin resistance. In situ Fast Activated cell-based ELISA (FACE) assays were performed to determine anti-apoptotic signaling molecules responsible for CCL25-CCR9 mediated survival.ResultsOur results show interactions between CCR9 and CCL25 increased anti-apoptotic signaling cascades in OvCa cells, which rescued cells from cisplatin-induced cell death. Specifically, CCL25-CCR9 interactions mediated Akt, activation as well as GSK-3β and FKHR phosphorylation in a PI3K-dependent and FAK-independent fashion.ConclusionsOur results suggest the CCR9-CCL25 axis plays an important role in reducing cisplatin-induced apoptosis of OvCa cells.

Administered CpG oligodeoxynucleotide induces mRNA expression of CXC and CC chemokines at the intestinal mucosa and PBMCs in piglets

Oligonucleotides containing CpG motifs (CpG ODN) are known to be potent stimulators of the innate immune system in vitro and in vivo. We therefore investigated if intranasal (IN)–mucosal or intramuscular (IM)–systemic administration of CpG ODN could enhance innate immunity in the intestinal mucosa and peripheral blood mononuclear cells (PBMCs) in piglets. Repeated IN or IM administration of CpG ODN significantly increased local/systemic mRNA expression of the CC chemokines macrophage inflammatory protein 1β (MIP-1β) and monocyte chemoattractant protein-1 (MCP-1) and CXC chemokine gamma interferon-inducible protein 10 (IP-10) and percentages of macrophages and cDCs in the intestine (jejunum, caecum and colon) and PBMCs by different kinetics. IN delivery of CpG ODN induced much stronger chemokine responses than IM delivery at intestinal mucosas, whereas IN delivery of CpG ODN induced some weaker chemokine responses than IM delivery in PBMCs. These findings suggest that IN administration of 100 μg/kg-CpG ODN without antigen codelivery may represent a valuable strategy for induction of innate immunity against infection.

Peroxiredoxin IV Regulates Pro-Inflammatory Responses in Large Yellow Croaker (Pseudosciaena crocea) and Protects against Bacterial Challenge

In this study, we applied a comparative proteomic approach to the analysis of differentially expressed proteins in the spleens of large yellow croaker following treatment with an inactivated trivalent bacterial vaccine. Twenty-four altered proteins were identified by MALDI-TOF or MALDI-TOF-TOF, including immune-related proteins, antioxidant proteins, signal transducers, protein biosynthesis and catabolism modulators, and carbonic anhydrases. Three Prx family members, namely, Prx I, Prx II, and Prx IV, were upregulated after treatment with the vaccine, indicating potentially important roles for these antioxidant proteins in the antibacterial immune response. Large yellow croaker Prx IV (LycPrxIV), which has thiol-dependent peroxidase activity, was constitutively expressed in all tissues examined. Immunoelectron microscopy showed that LycPrxIV was primarily localized to the rER or peroxisome in spleen cells of healthy fish, and its synthesis on the rER increased following treatment with bacterial vaccine. Suppression of LycPrxIV by siRNA resulted in an increase in NF-kappaB activity in spleen tissues, while in vivo administration of recombinant LycPrxIV (rLycPrxIV) caused a decrease in NF-kappaB activity, indicating that LycPrxIV negatively regulates NF-kappaB activation. Likewise, siRNA-mediated knockdown of LycPrxIV increased the expression of TNF-alpha and CC chemokine, and downregulated the expression of IL-10. However, injection of fish with rLycPrxIV induced the opposite expression pattern of these cytokines, suggesting a role for LycPrxIV in regulating pro-inflammatory responses. Bacterial challenge experiments showed that suppression of LycPrxIV expression by siRNA significantly increased fish mortality as compared to controls, whereas rLycPrxIV provided a protective effect. Together, our data suggest that LycPrxIV may regulate pro-inflammatory responses to protect large yellow croaker from bacterial challenge, revealing a novel antibacterial mechanism in fish.

Viral hemorrhagic septicemia and infectious pancreatic necrosis viruses replicate differently in rainbow trout gonad and induce different chemokine transcription profiles

Viral hemorrhagic septicemia virus (VHSV) and infectious pancreatic necrosis virus (IPNV) are two rainbow trout ( Oncorhynchus mykiss) pathogens. While IPNV is known to be vertically transmitted to the next generation through the oocyte, VHSV is known to replicate in the ovary and be transmitted horizontally through the ovarian fluid. In this work, we wanted to study whether these differences had an effect on the immune response triggered in the ovary, with a focus on the chemokine response. We have studied the kinetics of viral gene expression and the sites of replication, confirming that great differences exist between the replication of the two viruses in the gonad. Next, we studied the levels of expression of several CXC and CC chemokines in the ovary and found that while VHSV strongly triggered chemokine transcription, IPNV had almost no effect. This lack of immune response might be an advantage that permits its vertical transmission.

Size Effects of Polystyrene Nanoparticles on Atopic Dermatitis-like Skin Lesions in NC/NGA Mice

Nano-sized particles are diffusing in the environment with the development of nanotechnology. Polystyrene (PS) nanoparticles are modified industrial products and pharmaceutical agents, however, adverse effects of PS nanoparticles remain to be elucidated. In the present study, we investigated the effects of PS nanoparticles with different sizes on the atopic dermatitis (AD)-like skin lesions in NC/Nga mice assumed to show the skin barrier defect/dysfunction in the presence or absence of mite allergen. Male NC/Nga mice were injected intradermally with three different-sized PS nanoparticles (25, 50, or 100 nm) and/or mite allergen into their right ears. We evaluated clinical scores, ear thickening, histological findings and the local protein expression of inflammatory molecules in the ear and Ig production in serum. PS nanoparticles aggravated AD-like skin lesions related to mite allergen, which was paralleled by the local protein levels of interleukin-4, CCL2/monocyte chemotactic protein-1, CCL3/macrophage inflammatory protein-1 alpha, and CCL4/macrophage inflammatory protein-1 beta. In contrast, PS nanoparticles decreased interferon-gamma expression. Furthermore, exposure to PS nanoparticles induced ear swelling and CC-chemokine expression in the absence of allergen. These effects were greater with the smaller PS nanoparticles than with the larger ones regarding overall trend. These results suggest that exposure to PS nanoparticles under skin barrier defect/dysfunction can exacerbate AD-like skin lesions related to mite allergen in a size-dependent manner. The enhancing effects may be accounted for by T helper 2-biased immune responses. Furthermore, PS nanoparticles can evoke skin inflammation via the overexpression of CC-chemokines even in the absence of allergen in atopic subjects.

Chemokine induction by all-trans retinoic acid and arsenic trioxide in acute promyelocytic leukemia: triggering the differentiation syndrome

AbstractIn acute promyelocytic leukemia (APL), differentiation therapy with all-trans retinoic acid (ATRA) and/or arsenic trioxide can induce a differentiation syndrome (DS) with massive pulmonary infiltration of differentiating leukemic cells. Because chemokines are implicated in migration and extravasation of leukemic cells, chemokines might play a role in DS. ATRA stimulation of the APL cell line NB4 induced expression of multiple CC-chemokines (CCLs) and their receptors (> 19-fold), resulting in increased chemokine levels and chemotaxis. Induction of CCL2 and CCL24 was directly mediated by ligand-activated retinoic acid receptors. In primary leukemia cells derived from APL patients at diagnosis, ATRA induced chemokine production as well. Furthermore, in plasma of an APL patient with DS, we observed chemokine induction, suggesting that chemokines might be important in DS. Dexamethasone, which efficiently reduces pulmonary chemokine production, did not inhibit chemokine induction in APL cells. Finally, chemokine production was also induced by arsenic trioxide as single agent or in combination with ATRA. We propose that differentiation therapy may induce chemokine production in the lung and in APL cells, which both trigger migration of leukemic cells. Because dexamethasone does not efficiently reduce leukemic chemokine production, pulmonary infiltration of leukemic cells may induce an uncontrollable hyperinflammatory reaction in the lung.