Infection of cells with influenza A virus results in cell death with apoptotic characteristics. Apoptosis is regarded as a non-inflammatory process. However, during influenza an inflammatory response occurs in the airway epithelium. An examination of this apparent paradox was made using influenza A virus infection of human nasal and bronchiolar epithelial cells. Some cytokine genes (IL-18, CCL2 and CCL5) were expressed constitutively in nasal cells but no cytokine was released. In bronchiolar cells, IL-1 beta, IL-6 and CXCL8 expression was constitutive, whilst CCL2 and CCL5 expression was upregulated following influenza virus infection. IL-6, CXCL8 and CCL5 were released but IL-1 beta and CCL2 were not. In bronchiolar cells, cell death was inhibited by the caspase-8 (Z-IETD-fmk) and pan-caspase (Z-VAD-fmk) inhibitors and these inhibitors enhanced expression of CCL5 and increased the levels of the three secreted cytokines significantly. Thus, the amount of each cytokine released from bronchiolar cells is reduced during cell death, implying that the observed inflammatory response in influenza would be greater if cell death did not occur. Reduced cytokine release is also associated with fragmentation of the Golgi body, as the caspase inhibitors also rescued influenza A virus-induced fragmentation of the Golgi ribbon.

OBJECTIVE

Ascitic disease is a common occurrence in human ovarian cancer, but it is unclear how the cellular composition of ascitic fluid is determined. Because chemokines can determine host cell infiltration in solid ovarian cancer, we assessed CC chemokine protein and CC chemokine receptor expression in ovarian cancer ascites.

METHODS

We used reverse transcription-PCR and RNase protection assay to determine CC chemokine and chemokine receptor mRNA expression and ELISA to measure CC chemokine protein levels. Flow cytometry was used to identify cell populations and their chemokine receptor protein expression.

RESULTS

mRNA for the CC chemokines CCL2, -3, -4, -5, -8, and -22 was expressed in cell isolates from ascites samples, and the corresponding proteins were detected in ascitic fluid. mRNA for CC chemokine receptors CCR1, -2a, -2b, -3, -4, -5, and -8 was detected in cells from ascites. Fluorescence-activated cell-sorting analysis showed variable numbers of macrophages and CD3(+) T lymphocytes (predominantly CD4(+)) within ovarian cancer ascites. CD14(+) macrophages within ascites consistently expressed protein for CCR1, -2, and -5. CCR1 was expressed by >60% of all T cells, but more CD4(+) than CD8(+) T cells expressed CCR2 and -5. A direct correlation was found between the CCL5 concentration and CD3(+) T-cell infiltration.

CONCLUSIONS

We conclude that there is a complex chemokine/chemokine receptor network in ovarian cancer ascites. However, associations between chemokine receptor expression, chemokine levels, and cell counts were limited.

CD4 T cells, through the release of cytokines as well as direct effector functions, have been implicated in promoting inflammation of the atherosclerotic plaque. Plaque-infiltrating CD4 T cells include a specialized subset of (CD4+)CD28- T cells that express a unique profile of regulatory receptors and are responsive to novel microenvironmental cues. Here we report that (CD4+)CD28- T cells, either isolated from the plaque tissue or from the blood of patients with acute coronary syndrome (ACS), spontaneously express interleukin (IL)-12 receptors, even in the absence of antigenic stimulation. (CD4+)CD28- IL-12R+ cells responded to IL-12 stimulation with the upregulation of the chemokine receptor CCR5 and the C-type lectin receptor CD161, both implicated in regulating tissue homing of effector T cells. IL-12 treatment of (CD4+)CD28- T cells enhanced their chemotaxis and transendothelial migration toward the chemokine CCL5. In vivo relevance for the role of IL-12 in regulating the recruitment of (CD4+)CD28- T cells into the atheroma was examined in human atheroma-SCID mouse chimeras. Exposure of nonstimulated (CD4+)CD28- T cells to IL-12 was sufficient to amplify T-cell accumulation within the inflamed plaque, and coadministration of anti-CCR5 antibodies blocked T-cell recruitment into the plaque. Thus, (CD4+)CD28- T cells functionally resemble NK cells, which have proinflammatory activity even in the unprimed state and respond to any IL-12-inducing host infection with a shift in tissue trafficking and accrual in inflammatory lesions.

To elucidate the molecular mechanism of glomerular events in lupus nephritis, we performed genome-wide mRNA expression analysis of glomeruli microdissected from lupus mice. MRL/lpr mice (12-week-old) were orally given vehicle or prednisolone (10 mg/kg per day) for 4 weeks. Renal histology of MRL/lpr mice revealed mesangial proliferative glomerulonephritis with cellular infiltration of macrophages, T cells, and neutrophils. We identified 567 up-regulated genes in MRL/lpr glomeruli compared to control congenic mice. Those included complement components, adhesion molecules, chemokines and their receptors, and molecules related to antigen presentation. Over 130 genes were considered preferentially or exclusively expressed in hematopoietic cell lineages possibly reflecting leukocytes accumulation. Of note is the finding that chemokines and chemokine receptors (CCL3, CCL4, CCL5, CXCL9, CXCL10, CXCL11, CXCL16, CCR5, CXCR3, and CXCR6) that are related to T helper 1 (Th1) cells accumulation were up-regulated concomitantly with increased expression of Ebi3, a subunit of IL-27 that plays a role in Th1 predominance. These changes were accompanied by increased mRNA expression of many genes that were inducible by Th1 cytokine interferon-gamma. Prednisolone markedly attenuated glomerular lesion and leukocyte influx parallel with the reduction of enhanced gene expression. The present study shows additional evidence supporting glomerular Th1 cells accumulation and their role. Our data also provide an important resource in seeking new therapeutic targets to lupus nephritis. Supplemental table: available only at http://dx.doi.org/10.1254/jphs.FP0071337.

BACKGROUND

The cytokine/chemokine levels of individual follicular fluids (FFs) were measured to determine whether a biomarker could be linked to the developmental potential of the derived embryo.

METHODS

Fluid was collected from 132 individual FFs that were the source of oocytes subsequently fertilized and transferred. In each, a bead-based multiplex sandwich immunoassay (Luminex) was used to measure 28 cytokines and chemokines simultaneously.

RESULTS

Significantly higher levels of interleukin (IL-2) and interferon (IFN-gamma) were detected in FF for embryos that underwent early cleavage. IL-12 was significantly higher in FF corresponding to highly fragmented embryos and the chemokine CCL5 was significantly higher in FF related to the best quality (Top) embryos. The level of granulocyte colony-stimulating factor (G-CSF) in individual FF samples was correlated with the implantation potential of the corresponding embryo. The area under the receiver operating characteristics curve, which distinguished the embryos that definitely led to delivery from those that did not, was 0.84 (0.75-0.90) (P = 0.0001) for FF G-CSF. FF G-CSF was significantly lower in patients older than 36 years compared with those <30-year old. When the FF G-CSF was 20 pg/ml or higher, the ratio between Top and non-Top embryos was significantly higher than for the group with FF G-CSF below 20 pg/ml (45 versus 20.45%, P = 0.007).

CONCLUSIONS

Individual FF composition is related to the development of the corresponding in vitro generated embryo and its potential of implantation. Individual FF G-CSF may provide a non-invasive biomarker of implantation that needs to be evaluated together with in vitro observation to select the oocyte, and hence the embryo, to transfer.

Protective immunity to pathogens depends on efficient immune responses adapted to the type of pathogen and the infected tissue. Dendritic cells (DC) play a pivotal role in directing the effector T cell response to either a protective T helper type 1 (Th1) or type 2 (Th2) phenotype. Human monocyte-derived DC can be differentiated into Th1-, Th2- or Th1/Th2-promoting DC in vitro upon activation with microbial compounds or cytokines. Host defence is highly dependent on mobile leucocytes and cell trafficking is largely mediated by the interactions of chemokines with their specific receptors expressed on the surface of leucocytes. The production of chemokines by mature effector DC remains elusive. Here we assess the differential production of both inflammatory and homeostatic chemokines by monocyte-derived mature Th1/Th2-, Th1- or Th2-promoting DC and its regulation in response to CD40 ligation, thereby mimicking local engagement with activated T cells. We show that mature Th1- and Th1/Th2-, but not Th2-promoting DC, selectively express elevated levels of the inflammatory chemokines CCL2/MCP-1, CCL3/MIP-1alpha, CCL4/MIP-1beta and CCL5/RANTES, as well as the homeostatic chemokine CCL19/MIP-3beta. CCL21/6Ckine is preferentially expressed by Th2-promoting DC. Production of the Th1-attracting chemokines, CXCL9/Mig, CXCL10/IP-10 and CXCL11/I-TAC, is restricted to Th1-promoting DC. In contrast, expression of Th2-associated chemokines does not strictly correlate with the Th2-promoting DC phenotype, except for CCL22/MDC, which is preferentially expressed by Th2-promoting DC. Because inflammatory chemokines and Th1-associated chemokines are constitutively expressed by mature Th1-promoting DC and CCL22/MDC is constitutively expressed by mature Th2-promoting DC, we propose a novel role for mature DC present in inflamed peripheral tissues in orchestrating the immune response by recruiting appropriate leucocyte populations to the site of pathogen entry.

Experimental autoimmune encephalomyelitis (EAE) models multiple sclerosis (MS) and is characterized by marked mononuclear cell influx in the brain. Several studies have demonstrated a role for chemokines during EAE. It remains to be determined whether these mediators modulate EAE primarily by mediating leukocyte influx into the CNS or by modifying lymphocyte activation and/or trafficking into lymphoid organs. After induction of EAE with MOG(35-55), leukocyte recruitment peaked on day 14 and correlated with symptom onset, TNF-alpha production and production of CCL2 and CCL5. Levels of CXCL-10 and CCL3 were not different from control animals. Using intravital microscopy, we demonstrated that leukocyte rolling and adhesion also peaked at day 14. Treatment with anti-CCL2 or anti-CCL5 antibodies just prior to the intravital microscopy prevented leukocyte adhesion, but not rolling. Our data suggest that induction of leukocyte adhesion to the brain microvasculature is an important mechanism by which CCL2 and CCL5 participate in the pathophysiology of EAE.

BACKGROUND

Chemokine-controlled arterial leukocyte recruitment is a crucial process in atherosclerosis. Formyl peptide receptor 2 (FPR2) is a chemoattractant receptor that recognizes proinflammatory and proresolving ligands. The contribution of FPR2 and its proresolving ligand annexin A1 to atherosclerotic lesion formation is largely undefined.

OBJECTIVE

Because of the ambivalence of FPR2 ligands, we here investigate the role of FPR2 and its resolving ligand annexin A1 in atherogenesis.

RESULTS

Deletion of FPR2 or its ligand annexin A1 enhances atherosclerotic lesion formation, arterial myeloid cell adhesion, and recruitment. Mechanistically, we identify annexin A1 as an endogenous inhibitor of integrin activation evoked by the chemokines CCL5, CCL2, and CXCL1. Specifically, the annexin A1 fragment Ac2-26 counteracts conformational activation and clustering of integrins on myeloid cells evoked by CCL5, CCL2, and CXCL1 through inhibiting activation of the small GTPase Rap1. In vivo administration of Ac2-26 largely diminishes arterial recruitment of myeloid cells in a FPR2-dependent fashion. This effect is also observed in the presence of selective antagonists to CCR5, CCR2, or CXCR2, whereas Ac2-26 was without effect when all 3 chemokine receptors were antagonized simultaneously. Finally, repeated treatment with Ac2-26 reduces atherosclerotic lesion sizes and lesional macrophage accumulation.

CONCLUSIONS

Instructing the annexin A1-FPR2 axis harbors a novel approach to target arterial leukocyte recruitment. With the ability of Ac2-26 to counteract integrin activation exerted by various chemokines, delivery of Ac2-26 may be superior in inhibition of arterial leukocyte recruitment when compared with blocking individual chemokine receptors.

Infection with Trypanosoma cruzi, the etiologic agent of Chagas disease is accompanied by an intense inflammatory reaction. Our laboratory group has identified adipose tissue as one of the major sites of inflammation during disease progression. Because adipose tissue is composed of many cell types, we were interested in investigating whether the adipocyte per se was a source of inflammatory mediators in this infection. Cultured adipocytes were infected with the Tulahuen strain of T. cruzi for 48-96 h. Immunoblot and quantitative PCR (qPCR) analyses demonstrated an increase in the expression of proinflammatory cytokines and chemokines, including interleukin (IL)-1 beta, interferon-gamma, tumor necrosis factor-alpha, CCL2, CCL5, and CXCL10 as well as an increase in the expression of Toll-like receptors-2 and 9 and activation of the notch pathway. Interestingly, caveolin-1 expression was reduced while cyclin D1 and extracellular signal-regulated kinase (ERK) expression was increased. The expression of PI3kinase and the activation of AKT (phosphorylated AKT) were increased suggesting that infection may induce components of the insulin/IGF-1 receptor cascade. There was an infection-associated decrease in adiponectin and peroxisome proliferator-activated receptor-gamma (PPAR-gamma). These data provide a mechanism for the increase in the inflammatory phenotype that occurs in T. cruzi-infected adipocytes. Overall, these data implicate the adipocyte as an important target of T. cruzi, and one which contributes significantly to the inflammatory response observed in Chagas disease.

The rabies virus Ni-CE strain causes nonlethal infection in adult mice after intracerebral inoculation, whereas the parental Nishigahara (Ni) strain kills mice. We previously reported that the chimeric CE(NiN) strain with the N gene from the Ni strain in the genetic background of the Ni-CE strain kills adult mice, indicating that the N gene is related to the different pathogenicities of Ni and Ni-CE strains. In the present study, to obtain an insight into the mechanism by which the N gene determines viral pathogenicity, we compared the effects of Ni, Ni-CE, and CE(NiN) infections on host gene expressions using a human neuroblastoma cell line. Microarray analysis of these infected cells revealed that the expression levels of particular genes in Ni- and CE(NiN)-infected cells, including beta interferon (IFN-beta) and chemokine genes (i.e., CXCL10 and CCL5) were lower than those in Ni-CE-infected cells. We also demonstrated that Ni-CE infection activated the interferon regulatory factor 3 (IRF-3)-dependent IFN-beta promoter and induced IRF-3 nuclear translocation more efficiently than did Ni or CE(NiN) infection. Furthermore, we showed that Ni-CE infection, but not Ni or CE(NiN) infection, strongly activates the IRF-3 pathway through activation of RIG-I, which is known as a cellular sensor of virus infection. These findings indicate that the N protein of rabies virus (Ni strain) has a function to evade the activation of RIG-I. To our knowledge, this is the first report that the Mononegavirales N protein functions to evade induction of host IFN and chemokines.

BACKGROUND

Mucosal macrophages are involved in the maintenance of epithelial barrier integrity and the elimination of invading pathogens. Although an intestinal barrier defect and microbial translocation are hallmarks of human immunodeficiency virus (HIV) infection, recent data on gut mucosal macrophages in HIV infection are sparse.

METHODS

Treatment-naive and treated HIV-infected patients and healthy controls were studied for frequencies and functional parameters of blood monocytes and macrophages in duodenal mucosa.

RESULTS

We found mucosal enrichment of macrophages in untreated HIV infection associated with reduced monocyte counts in blood and increased monocyte expression of the gut-homing molecule integrin β7. Increased CCR2 density on integrin β7-expressing monocytes and mucosal secretion of CCL2 suggest that CCR2/CCL2-chemotaxis is involved in enhanced trafficking of blood monocytes to the gut. Secretion of macrophage-related proinflammatory molecules interleukin 1β, CCL5, CXCL9, and CXCL10 was increased in the gut mucosa of untreated patients. Moreover, mucosal macrophages of untreated patients showed reduced phagocytic activity.

CONCLUSIONS

These data suggest a role for gut mucosal macrophages in HIV immune pathogenesis: infiltrated macrophages in the intestinal mucosa may promote local inflammation and tissue injury, whereas their low phagocytic activity prevents the efficient elimination of luminal antigens that cross the damaged intestinal barrier.

Infection of the central nervous system (CNS) with herpes simplex virus (HSV)-1 initiates a rapidly progressive, necrotizing, and fatal encephalitis in humans. Even with the advent of antiviral therapy, effective treatments for HSV-1 brain infection are limited because the cause of the resulting neuropathogenesis is not completely understood. We previously reported that human microglial cells, while nonproductively infected, respond to HSV-1 by producing robust amounts of pro-inflammatory mediators, such as tumor necrosis factor(TNF), interleukin (IL)-1beta, CCL5 (RANTES), and CXCL10 (IP-10). Although initiation of immune responses by glial cells is an important protective mechanism in the CNS, unrestrained inflammatory responses may result in irreparable brain damage. To elucidate the potential immunomodulatory role of anti-inflammatory cytokines, we investigated the effects of IL-4, IL-10, and transforming growth factor (TGF)-beta on microglial cell cytokine and chemokine production in response to HSV-1. Results from these studies demonstrated a consistent IL-10-mediated suppression of TNF-alpha (60% +/- 2%), IL-1beta (68% +/- 3%), CCL5 (62 +/- 4%), but not CXCL10 production by HSV-1-infected microglial cells. This inhibition was associated with decreased HSV-1-induced activation of NF-kappaB. These results suggest that IL-10 has the ability to regulate microglial cell production of immune mediators and thereby, dampen the pro-inflammatory response to HSV-1.

BACKGROUND

In neuroinflammatory diseases, macrophages can play a dual role in the process of tissue damage, depending on their activation status (M1 / M2). M1 macrophages are considered to exert damaging effects to neurons, whereas M2 macrophages are reported to aid regeneration and repair of neurons. Their migration within the central nervous system may be of critical importance in the final outcome of neurodegeneration in neuroinflammatory diseases e.g. multiple sclerosis (MS). To provide insight into this process, we examined the migratory capacity of human monocyte-derived M1 and M2 polarised macrophages towards chemoattractants, relevant for neuroinflammatory diseases like MS.

METHODS

Primary cultures of human monocyte-derived macrophages were exposed to interferon gamma and lipopolysaccharide (LPS) to evoke proinflammatory (M1) activation or IL-4 to evoke anti-inflammatory (M2) activation. In a TAXIScan assay, migration of M0, M1 and M2 towards chemoattractants was measured and quantified. Furthermore the adhesion capacity and the expression levels of integrins as well as chemokine receptors of M0, M1 and M2 were assessed. Alterations in cell morphology were analysed using fluorescent labelling of the cytoskeleton.

RESULTS

Significant differences were observed between M1 and M2 macrophages in the migration towards chemoattractants. We show that M2 macrophages migrated over longer distances towards CCL2, CCL5, CXCL10, CXCL12 and C1q compared to non-activated (M0) and M1 macrophages. No differences were observed in the adhesion of M0, M1 and M2 macrophages to multiple matrix components, nor in the expression of integrins and chemokine receptors. Significant changes were observed in the cytoskeleton organization upon stimulation with CCL2, M0, M1 and M2 macrophages adopt a spherical morphology and the cytoskeleton is rapidly rearranged. M0 and M2 macrophages are able to form filopodia, whereas M1 macrophages only adapt a spherical morphology.

CONCLUSIONS

Together our results indicate that the alternative activation status of macrophages promotes their migratory properties to chemoattractants relevant for neuroinflammatory diseases like MS. Conversely, classically activated, proinflammatory macrophages have reduced migratory properties. Based on our results, we postulate that the activation status of the macrophage influences the capacity of the macrophages to rearrange their cytoskeleton. This is the first step in understanding how modulation of macrophage activation affects macrophage migration in neuroinflammatory diseases like MS.

Cross-talk between tumor cells and their microenvironment is critical for malignant progression. Cross-talk mediators, including soluble factors and direct cell contact, have been identified, but roles for the interaction of physical forces between tumor cells and the bone microenvironment have not been described. Here, we report preclinical evidence that tumor-generated pressure acts to modify the bone microenvironment to promote the growth of prostate cancer bone metastases. Tumors growing in mouse tibiae increased intraosseous pressure. Application of pressure to osteocytes, the main mechanotransducing cells in bone, induced prostate cancer growth and invasion. Mechanistic investigations revealed that this process was mediated in part by upregulation of CCL5 and matrix metalloproteinases in osteocytes. Our results defined the critical contribution of physical forces to tumor cell growth in the tumor microenvironment, and they identified osteocytes as a critical mediator in the bone metastatic niche.

Recognition of viral double-stranded RNA by Toll-like receptor 3 (TLR3) triggers activation of the transcription factors NF-κB and interferon regulated factor 3, leading to induction of type I interferons and proinflammatory cytokines. TIR-domain-containing adapter-inducing interferon-β (TRIF) is an adapter protein required for TLR3-mediated signaling. Here we identified the E3 ubiquitin ligase WW domain-containing protein 2 (WWP2) as a TRIF-associated protein by biochemical purification. WWP2 mediated K48-linked ubiquitination and degradation of TRIF upon TLR3 activation. Overexpression of WWP2 inhibited TLR3-mediated NF-κB and interferon regulated factor 3 activation, whereas knockdown of WWP2 had opposite effects. We generated Wwp2-deficient mice to further investigate the roles of Wwp2 in innate immune responses. Consistently, production of IFN-β, CCL5, TNFα, and IL-6 in response to the TLR3 ligand poly(I:C) was elevated in Wwp2(-/-) macrophages and Wwp2-deficient mice exhibited increased susceptibility to poly(I:C)-induced death than the control littermates. Our findings suggest that WWP2 negatively regulates TLR3-mediated innate immune and inflammatory responses by targeting TRIF for ubiquitination and degradation.

Chemokine-driven interactions of immune cells are essential for effective antitumor immunity. Human natural killer (NK) cells can be primed by the interleukin (IL)-1-related proinflammatory cytokine IL-18 for unique helper activity, which promotes dendritic cell (DC) activation and DC-mediated induction of type-1 immune responses against cancer. Here, we show that such IL-18-primed "helper" NK cells produce high levels of the immature DC (iDC)-attracting chemokines CCL3 and CCL4 upon exposure to tumor cells or the additional inflammatory signals IFN-α, IL-15, IL-12, or IL-2. These "helper" NK cells potently attract iDCs in a CCR5-dependent mechanism and induce high DC production of CXCR3 and CCR5 ligands (CXCL9, CXCL10, and CCL5), facilitating the subsequent recruitment of type-1 effector CD8(+) T (Teff) cells. Using cells isolated from the malignant ascites of patients with advanced ovarian cancer, we show that "helper" NK cell-inducing factors can be used to enhance local production of Teff cell-recruiting chemokines. Our findings reveal the unique chemokine expression profile of "helper" NK cells and highlight the potential for using two-signal-activated NK cells to promote homing of type-1 immune effectors to the human tumor environment.

CCL5 (previously called RANTES) is in the CC-chemokine family and plays a crucial role in the migration and metastasis of human cancer cells. On the other hand, the effect of CCL5 is mediated via CCR receptor. RT-PCR and flow cytometry studies demonstrated CCR5 but not CCR1 and CCR3 mRNA in oral cancer cell lines, especially higher in those with high invasiveness (SCC4) as compared with lower levels in HSC3 cells and SCC9 cells. Stimulation of oral cancer cells with CCL5 directly increased the migration and metalloproteinase-9 (MMP-9) production. MMP-9 small interfering RNA inhibited the CCL5-induced MMP-9 expression and thereby significantly inhibited the CCL5-induced cell migration. Activations of phospholipase C (PLC), protein kinase Cdelta (PKCdelta), and NF-kappaB pathways after CCL5 treatment was demonstrated, and CCL5-induced expression of MMP-9 and migration activity was inhibited by the specific inhibitor of PLC, PKCdelta, and NF-kappaB cascades. In addition, migration-prone sublines demonstrate that cells with increasing migration ability had more expression of MMP-9, CCL5, and CCR5. Taken together, these results indicate that CCL5/CCR5 axis enhanced migration of oral cancer cells through the increase of MMP-9 production.

Microglia have the ability to eliminate amyloid β (Aβ) by a cell-specific phagocytic mechanism, and bone marrow (BM) stem cells have shown a beneficial effect through endogenous microglia activation in the brains of Alzheimer's disease (AD) mice. However, the mechanisms underlying BM-induced activation of microglia have not been resolved. Here we show that BM-derived mesenchymal stem cells (MSCs) induced the migration of microglia when exposed to Aβ in vitro. Cytokine array analysis of the BM-MSC media obtained after stimulation by Aβ further revealed elevated release of the chemoattractive factor, CCL5. We also observed that CCL5 was increased when BM-MSCs were transplanted into the brains of Aβ-deposited AD mice, but not normal mice. Interestingly, alternative activation of microglia in AD mice was associated with elevated CCL5 expression following intracerebral BM-MSC transplantation. Furthermore, by generating an AD-green fluorescent protein chimeric mouse, we ascertained that endogenous BM cells, recruited into the brain by CCL5, induced microglial activation. Additionally, we observed that neprilysin and interleukin-4 derived from the alternative microglia were associated with a reduction in Aβ deposition and memory impairment in AD mice. These results suggest that the beneficial effects observed in AD mice after intracerebral SC transplantation may be explained by alternative microglia activation. The recruitment of the alternative microglia into the brain is driven by CCL5 secretion from the transplanted BM-MSCs, which itself is induced by Aβ deposition in the AD brain.

Human Alport disease is caused by a lack of the alpha3-, 4-, or 5-chain of type IV collagen (COL4A). Affected humans and COL4A3-deficient mice develop glomerulosclerosis and progressive renal fibrosis in the presence of interstitial macrophages, but their contribution to disease progression is under debate. This question was addressed by treating COL4A3-deficient mice with BX471, an antagonist of chemokine receptor 1 (CCR1) that is known to block interstitial leukocyte recruitment. Treatment with BX471 from weeks 6 to 10 of life improved survival of COL4A3-deficient mice, associated with less interstitial macrophages, apoptotic tubular epithelial cells, tubular atrophy, interstitial fibrosis, and less globally sclerotic glomeruli. BX471 reduced total renal Cll5 mRNA expression by reducing the number of interstitial CCL5-positive cells in inflammatory cell infiltrates. Intravital microscopy of the cremaster muscle in male mice identified that BX471 or lack of CCR1 impaired leukocyte adhesion to activated vascular endothelium and transendothelial leukocyte migration, whereas leukocyte rolling and interstitial migration were not affected. Furthermore, in activated murine macrophages, BX471 completely blocked CCL3-induced CCL5 production. Thus, CCR1-mediated recruitment and local activation of macrophages contribute to disease progression in COL4A3-deficient mice. These data identify CCR1 as a potential therapeutic target for Alport disease or other progressive nephropathies associated with interstitial macrophage infiltrates.

OBJECTIVE

Cytokines and chemokines play an important role in the pathogenesis of periodontal diseases. The objective of this study was to quantitatively assess the effect of initial periodontal therapy on gingival crevicular fluid levels of a comprehensive panel of cytokines and chemokines, including several less extensively studied mediators.

METHODS

Clinical examinations were performed and gingival crevicular fluid samples obtained from six subjects with generalized severe chronic periodontitis prior to initial periodontal therapy and at re-evaluation (6-8 weeks). Four diseased and two healthy sites were sampled in each subject. Twenty-two gingival crevicular fluid mediators were examined using a multiplex antibody capture and detection platform. Statistical analyses were performed by fitting mixed effects linear models to log-transformed gingival crevicular fluid values.

RESULTS

Gingival crevicular fluid interleukin (IL)-1alpha and IL-1beta were the only cytokines to differ in initially diseased vs. initially healthy sites. Following initial therapy, 13 of the 16 detectable cytokines and chemokines decreased significantly in diseased sites, including IL-1alpha, IL-1beta, IL-2, IL-3, IL-6, IL-7, IL-8, IL-12 (p40), CCL5/regulated on activation, normally T cell expressed and secreted (RANTES), eotaxin, macrophage chemotactic protein-1, macrophage inflammatory protein-1alpha and interferon-gamma. At healthy sites, only three of the 16 mediators were significantly altered following therapy.

CONCLUSIONS

This is the first study, to our knowledge, to evaluate such an extensive panel of gingival crevicular fluid mediators within the same sample prior to and following initial therapy. The results confirm that periodontal therapy effectively reduces pro-inflammatory cytokines and chemokines, including less well-described mediators that may be important in initiation and progression of periodontitis. The multiplex assay will prove useful for future gingival crevicular fluid studies.

BACKGROUND

Chemokines (CKs) may promote antitumor immunity in cancer, act as tumor growth factors, influence metastatic spreading or angiogenesis. The purpose of this study was to investigate whether CK expression is altered in colorectal carcinomas compared to normal mucosa and to elucidate its possible clinico-pathological implications.

METHODS

The levels of CCL2 (MCP-1), CCL4 (MIP-1beta), CCL5 (RANTES), CXCL 1 (GRO-alpha), CXCL 5 (ENA-78) and CXCL 8 (IL-8) were investigated in 10 colorectal carcinomas and their corresponding normal mucosa by the use of ELISA.

RESULTS

All CK analyzed, with the exception of CCL5 (RANTES), were expressed at a significantly higher level in malignant tissue.

CONCLUSIONS

Therapeutic studies in colon carcinomas should, therefore, focus more on the neutralization of CKs than on their application.

Severe malarial anemia (MA) is the primary manifestation of severe malaria among children in areas of holoendemic Plasmodium falciparum transmission. Although overproduction of inflammatory-derived cytokines are implicated in the immunopathogenesis of severe MA, chemokines such as regulated on activation, normal T-cell expressed and secreted (RANTES, CCL5) are largely unexplored in childhood malaria. We found that RANTES is decreased during severe MA (p<0.01), and associated with suppression of erythropoiesis (p<0.05) and malaria-induced thrombocytopenia (p<0.05). These findings suggest that thrombocytopenia may be a source of reduced RANTES which may contribute, at least in part, to suppression of erythropoiesis in children with malarial anemia.

Susceptibility to HIV infection and AIDS progression is variable among individuals and populations, and in part genetically determined. Genetic variants of genes encoding HIV co-receptors and their chemokine ligands have been described, and some of these variants were associated with resistance to HIV infection and/or disease progression. We review here the reported data regarding the variants of the CCR5, CCR2, CX3CR1, MIP-1alpha/CCL3, MIP-1beta/CCL4, RANTES/CCL5 and SDF-1/CXCL12 genes. The Delta32 deletion mutant of CCR5, resulting in a non-functional receptor not reaching the cell surface, is unambiguously associated with strong, although incomplete, resistance to HIV infection for homozygotes, and retarded progression for heterozygotes. Specific haplotypes encompassing the CCR5 and CCR2 loci, and the copy number of the CCL3L1 gene, have also been convincingly correlated with delayed progression. For other gene variants, involving CXCL12/SDF-1 and CX3CR1, conclusive evidence for their relevance in the frame of HIV susceptibility is still lacking.

Toll-IL-1R domain-containing adaptor-inducing IFN-beta (TRIF) is an adaptor molecule that mediates a distinct TLR signaling pathway. Roles of TRIF in the host defense have been primarily associated with virus infections owing to the induction of IFN-alphabeta. In this study, we investigated a role of TRIF in Pseudomonas aeruginosa infection. In vitro, TRIF-deficient mouse alveolar and peritoneal macrophages showed a complete inhibition of RANTES (CCL5) production, severely impaired TNF and KC (CXCL1) production, and reduced NF-kappaB activation in response to P. aeruginosa stimulation. In vivo, TRIF-deficient mice showed a complete inhibition of RANTES production, a severely impaired TNF and KC production, and an efficient MIP-2 and IL-1beta production in the lung following P. aeruginosa infection. This outcome was associated with a delayed recruitment of neutrophils into the airways. These results suggest that TRIF mediates a distinct cytokine/chemokine profile in response to P. aeruginosa infection. P. aeruginosa-induced RANTES production is completely dependent on TRIF pathway in mice. Importantly, TRIF deficiency leads to impaired clearance of P. aeruginosa from the lung during the initial 24-48 h of infection. Thus, TRIF represents a novel mechanism involved in the development of host response to P. aeruginosa infection.