The core structure of the ligand recognized by NOD-1 is the pepti

The core structure of the ligand recognized by NOD-1 is the peptidoglycan-specific dipeptide, γ-D-glutamyl-meso-diaminopimelic Epacadostat acid (iE-DAP) and NOD-2 recognizes the muramyldipeptide (MDP), representing the minimal motif of bacterial peptidoglycan able of activating NOD2 [15]. Given the significance of TLR and NLR in immunity and cell differentiation, in this study we explored the expression of NLR in MSC, the transcriptional response of MSC to NOD-1 and TLR-2 ligands and the ability of galectin-3, an identified candidate gene, to affect the inhibitory function of MSC on T-cell proliferation to alloantigens. The peptidoglycan-specific dipeptide, γ-D-glutamyl-meso-diaminopimelic acid

(iE-DAP, a NOD1 ligand) and control peptide (iE-Lys) were purchased from InvivoGen (Toulouse, France) Pam3CS(K)4, and a TLR2 ligand was purchased from Calbiochem (La Jolla, CA, USA). Conjugated anti-CD14, anti-CD4 were purchased from DakoCytomation (Copenhagen, Denmark). Conjugated anti-CD34, anti-CD105, anti-CD106 and anti-NOD2 monoclonal antibody (2D9) were purchased from BD Biosciences (Franklin Lakes, NJ, USA). Anti-NOD1 polyclonal antibodies were purchased from Cell Signalling (Danvers, MA, USA). Total RNA isolation kit Trizol and cDNA synthesis kit were purchased from Invitrogen (San Diego, CA, USA) and GE Healthcare AS (Oslo, Norway), respectively.

SYBR Green PCR Master Mix was purchased from Applied Biosystems (Foster City, CA, USA). An Illumina TotalPrep RNA Amplification Kit was purchased from Ambion (Austin, TX, USA). Expression arrays were purchased from Illumina (San Diego, CA, USA). Human VEGF monoclonal antibody (clone 26503, capture antibody), human VEGF 165 biotinylated affinity purified polyclonal antibodies (detection antibody) and the galectin ELISA kit were purchased from R&D systems (Abingdon, UK). MSC were isolated and expanded from bone marrow (BM) taken from iliac crest of adult volunteers with informed consent.

Heparinized BM was mixed with double volume of phosphate-buffered saline, and mononuclear cells were prepared by gradient centrifugation Thiamine-diphosphate kinase (Lymphoprep). Subsequently, the cells were cultured in 75-cm2 flask at a concentration of 30 × 106 per 20 ml Dulbecco’s modified Eagle’s medium (DMEM) supplemented with 10% foetal calf serum (FCS). Cultures were incubated at 37 °C in a humidified atmosphere containing 5% CO2. After 48- to 72-h incubation, non-adherent cells were removed and adherent cells constituted the MSC cell population that was expanded. Cells were detached by a treatment with trypsin and EDTA (GibcoBRL, Grand Island, NY, USA) and replated at a density of 106 cells/75 cm2 flask. These cells were verified for positive staining for CD105 and CD106, and are negative for CD14, CD34 and CD4 markers. MSC were detached using trypsin/EDTA, resuspended in complete medium and placed at 37 °C for 2 h. Subsequently, cell aliquots (5 × 105) were incubated on ice with conjugated monoclonal antibodies against CD34, CD14, CD4, CD105 and CD106.

One patient with adynamic bone disease subsequently developed bio

One patient with adynamic bone disease subsequently developed biochemical recurrence of hyperparathyroidism. Serial bone densitometry showed remarkable improvement. There was no fracture. Conclusion:  In the studied series of total parathyroidectomy

without autoimplant, adynamic buy Opaganib bone disease occurred in three out of seven repeat bone biopsies while improvement occurred in the rest. Bone mineral density was much improved and there was no fracture. “
“Nephrogenesis is dependent on the input of several transcriptional regulatory networks. However, the details of how these networks operate and converge to facilitate nephron progenitor specific programmes are largely unknown. To this end, recent studies have focused on identifying the precise regulatory mechanisms that modulate progenitor maintenance and induction. Continued focus on this area of research will help identify Selleckchem RAD001 nephrogenic programmes which could be manipulated for therapeutic intervention of kidney disease. The eloquent progression of nephrogenesis during embryonic kidney development requires a careful balance of nephron progenitor self-renewal and differentiation. This ensures a sufficient number of nephrons are formed to carry out their essential roles in waste filtration and body fluid homeostasis. In mammals this is a terminal process; no resident progenitors remain after fetal or early neonatal

stages. De novo nephron formation does not appear to be an option for the adult mammalian kidney, necessitating repair of existing nephrons following injury or disease. In this light, developing alternative, knowledge-based strategies to induce de novo nephrogenesis is an important therapeutic goal. As a first step, we need to develop a thorough understanding of the nephron progenitor population and the underlying regulatory

programmes governing its maintenance and nephron-specific capabilities. Leveraging this knowledge base will spur the development of new strategies to treat the damaged and diseased ADP ribosylation factor kidney. The mammalian kidney develops through reciprocal interactions of the ureteric epithelium with adjacent mesenchymal nephron progenitors. Signals from nephron progenitors support ureteric epithelial branching and the arborization of the urine transporting collecting duct network derived from this epithelium. In turn, the transition of multi-potent nephron progenitors into epithelial renal vesicles, the nephron precursor, requires signals from the ureteric bud. Over the last few decades, research efforts have uncovered a number of factors with integral roles in kidney development. In particular, the transcriptional regulators and associated components including: Six1, Pax2, Hox11 paralogs, Osr1, Sall1, Six2, Eya1 and Wt1 are all expressed within the nephron progenitors, and the depletion of each from the murine kidney results in insufficient kidney development.

33,36,41,42 The in vitro differentiation studies described above

33,36,41,42 The in vitro differentiation studies described above can only address

issues of sufficiency for a cytokine to regulate the development of specific phenotypes. However, when assessed in vivo, IFN-α/β signalling seemed to contribute to Th1 development.43,44 Likewise, mice deficient in IL-12 were still able to generate Th1 cells in response to murine hepatitis virus infection, demonstrating that multiple pathways were involved and may be required for Th1 development.45 One possible pathway involves IL-18, which was shown to synergize with IFN-α/β to activate STAT4 in the absence of IL-12.46,47 Interferon-α/β also promotes the expression of IL-21 and the IL-21R in T cells.48 Panobinostat ic50 As IL-21 induces Th1-associated genes, possibly in synergy with IL-18, this may represent another pathway by which IFN-α/β contributes to Th1 development.49,50 Taken together, these studies suggest that while IFN-α/β is not sufficient to drive Th1 commitment via direct and sustained STAT4 activation, it contributes to Th1 responses in vivo by collaborating with other cytokines that are differentially induced in response to various classes of pathogens. Finally, IFN-α/β may play a broader role in CD4+ T-cell functions by check details regulating the development and stability of long-lived memory cells. Although IFN-α/β may promote

cell cycle arrest and, in some cases, apoptosis in certain cell types, CD4+ T cells respond quite differently depending upon their activation status. Marrack et al.51 demonstrated that IFN-α/β protected cells from undergoing acute activation-induced cell death. Though not directly driving proliferation, IFN-α/β seemed to block apoptosis following antigen stimulation in vitro, which may be related to the development of

long-lived central memory cells. As central memory cells were first described as having decreased effector capabilities, they display enhanced recall proliferation coincident with elevated secretion of IL-2.52 Recently, Davis et al.53 demonstrated a direct role for IFN-α/β in promoting the development of human central memory-like Staurosporine concentration CD4+ T cells and preserving elevated IL-2 expression preferentially within these cells versus their effector cell counterparts. Hence, IFN-α/β acts to prevent terminal differentiation of effector CD4+ T cells by selectively regulating IL-2 expression at the expense of driving inflammatory cytokine secretion. As IFN-α/β is induced during Th1-dominant antiviral immune responses, IFN-α/β production may act to suppress the development of other subsets and their associated effector functions. Indeed, a growing body of literature has highlighted the role of IFN-α/β in cross-regulating the differentiation and stability of both Th2 and Th17 cells. These two subsets are guided by distinct signals, with Th2 cells controlled by IL-4, and Th17 cells responding to transforming growth factor-β, IL-6 and IL-1β.

5-fold, 21-fold, 9 5-fold, 18 5-fold and 28 5-fold, respectively)

5-fold, 21-fold, 9.5-fold, 18.5-fold and 28.5-fold, respectively), indicating that the RT-PCR results were generally consistent with the expression patterns observed in the secretome analysis (Table 1). As IFI16 increases the expression of genes encoding inflammatory chemokines, to confirm these inductions at the protein level, representative chemokines were also quantified by ELISA in supernatants from both LacZ and IFI16 HUVEC supernatants 60 h postinfection. As shown in Fig. 2, the CCL4 protein levels are 28-fold higher in supernatants from IFI16

HUVEC-infected cells compared with those in the supernatants from LacZ-infected cells (86±24 versus 3±4 pg/mL, mean±SEM), the CCL5 protein levels are fourfold higher (273±39 versus 74±32 pg/mL) and the CCL20 protein levels are about threefold Palbociclib higher in supernatants from IFI16 HUVEC-infected cells (312±30 versus 102±8 pg/mL). This analysis provides the first glimpse into the complexity of the IFI16 secretome and confirms its ability to trigger proinflammatory activity in EC. The IFI16 gene

is known to be induced by IFN, however, to confirm the role of IFI16 as the mediator of IFN pro-inflammatory activity, we investigated whether the array of inflammatory molecules stimulated in HUVEC by treatment with IFN-β overlapped with that observed in IFI16-infected cells. To do so, EC were treated with IFN-β or left untreated. EGFR inhibitor After 24 h, total RNA were extracted, retrotranscribed Farnesyltransferase into cDNA and analyzed by RT-PCR and the arrays of expressed proinflammatory genes compared. As shown in Fig. 3, treating HUVEC with IFN-β resulted in the upregulation of a series of proinflammatory genes, including ICAM-1, CCL3, CCL4, CCL5, CCL20 and IL-1β (6.35-fold, 10.4-fold, 6.1-fold,

58.7-fold, 26.8-fold and 8.71-fold, respectively) that were also observed to be upregulated in HUVEC overexpressing IFI16. To determine whether the increase in expression of inflammatory molecules was a consequence of stimulating the encoding genes at the transcriptional level, we analyzed the effects of IFI16 on the expression of the transiently transfected luciferase reporter gene driven by the promoters of either CCL20 or ICAM-1. HUVEC were transiently transfected with the indicated plasmids and then infected with either adenovirus containing the IFI16 gene (AdVIFI16) or AdVLacZ, or otherwise left uninfected. Thirty-six hours postinfection, cell extracts were prepared and assayed for luciferase activity. As shown in Fig. 4, IFI16 overexpression led to an increase in the expression of the luciferase reporter gene driven by either the CCL20 promoter (3.8-fold) or the ICAM-1 promoter (11.5-fold) (used as positive control) compared with extracts from AdVLacZ-infected HUVEC. Previous results have demonstrated that NF-κB is the main mediator of IFI16-driven ICAM-1 induction responsible for leukocyte adhesion to the endothelium 9.

neoformans antigens to primed T cells after the immune response h

neoformans antigens to primed T cells after the immune response had peaked and the immunoglobulin

switch from the initial IgM had also occurred, thereby helping the development of a more effective protective Th1 immune response. In summary, the present study demonstrates that opsonized live GDC-0973 cost yeasts of C. neoformans activate eosinophils, inducing the expression of MHC class I, MHC class II and costimulatory molecules. Furthermore, although the secretion of proinflammatory cytokines is also increased, the production of oxygen and nitrogen radicals is down-regulated. These activated eosinophils can also stimulate CD4+ and CD8+ T cells to produce an antigen-specific immune response, thus creating a Th1 microenvironment. These results suggest that, in addition to their role as effector cells, eosinophils may also serve as specific APCs during fungal infection. Moreover, the fact that eosinophils are able to communicate with T cells suggests that they

could be involved in the adaptive immune response to C. neoformans. The present work was supported by grants from Agencia Nacional de Promoción Científica y Tecnológica (PICT 33326); Consejo Nacional de Investigaciones Científicas y Técnicas de Argentina (PIP 6327); Secretaría de Ciencia y Tecnología (SeCyT), Universidad Nacional de Córdoba (Grant 69/08); and Ministerio de Ciencia y Tecnología de la Provincia de Córdoba (Grant 2008). A. P. Garro selleck screening library and J. L. Baronetti are PhD fellows of Consejo Nacional de Investigaciones Científicas y Técnicas, and L. S. Chiapello and D. T. Masih are members of the Research Career of Consejo Nacional de Investigaciones Científicas y Técnicas. We would like to thank native speaker,

Paul Hobson for revision of the manuscript. The authors have no conflicts of interest to disclose. Figure S1. Flow cytometry analysis of the percentage of contaminating cells between eosinophil populations. Figure S2.Cryptococcus neoformans-pulsed eosinophils do not promote the production of Th 2 type cytokines by Ag-specific CD4+ and CD8+ T cells. “
“The implication of B lymphocytes in the immunopathology of multiple sclerosis (MS) is increasingly recognized. Here we investigated the response of B cells to IFN-β, a first-line therapy for relapsing-remitting MS patients, upon stimulation with TLR. IFN-β restored the frequency of TLR7-induced IgM and IgG-secreting cells in MS patients to the levels found in healthy donors, showing a specific deficiency in the TLR7 pathway. However, no difference was observed in the TLR9 response. Furthermore, in MS-derived PBMCs, TLR7-mediated production of IL-6 and the ex vivo expression of B-cell-activating factor of the TNF family, two crucial cytokines for B-cell differentiation and survival, were induced by IFN-β.

In summary, we found that ST2 promoter usage is largely cell-type

In summary, we found that ST2 promoter usage is largely cell-type dependent but does not dictate splicing. Moreover, the proximal promoter is not a major driver of circulating soluble ST2 under the conditions tested. il-33 is a tissue-derived cytokine that enhances Th2- and allergy-associated inflammation by activating a membrane-spanning receptor known as ST2 (or ST2L). ST2L encompasses a ligand-binding domain combined with an intracellular TIR domain required for signaling. In addition, a soluble form of the receptor (sST2) is encoded by a transcript

variant that lacks the exons for the transmembrane and cytoplasmic domains. sST2 binds to IL-33 but is unable to transmit a signal thereby acting as a decoy molecule Gefitinib price that regulates inflammation by neutralizing IL-33 in solution [1]. Regulation of sST2 expression is therefore related to regulation of IL-33 activity. The sST2 transcript was identified over 20 years ago as a gene induced in either mouse [2] or rat [3] fibroblasts in response to oncogenes, serum, and other mitogenic stimuli. Optimal sST2 induction in fibroblasts requires a TPA-responsive enhancer

element upstream of the promoter [4]. In comparison, the ST2L transcript represents an alternatively spliced mRNA [5] expressed predominantly in mast cells and other hematopoietic cell lineages. Mast cells and Th2 cells employ a more distal promoter, which contains Th2-associated GATA elements and lies 10 kb upstream of the promoter described in fibroblasts [6, 7]. Several studies have addressed the link between the unique ST2 promoters and generation of either ST2L or sST2. A study LY2157299 solubility dmso with rat cells suggested that expression of the two ST2 variants is largely governed by transcriptional regulation, with sST2 linked to the proximal promoter in fibroblasts and ST2L linked to the distal promoter

in hematopoetic cells [8]. However, another group found ST2L expression in mouse mast cells to be dependent on the distal promoter and ST2 expression in fibroblasts (mostly sST2, but also ST2L) linked to the proximal promoter, suggesting that promoter usage was cell type but not transcript specific [6]. Collectively, these findings suggest that ST2 promoter usage is mostly cell-type specific and that transcription from the proximal promoter in fibroblasts is a potential source of sST2 in vivo. Soluble ST2 protein cAMP is present in serum at up to ng/mL concentrations and is often elevated in inflammatory, infectious, or other disease situations [9-11]. Circulating sST2 concentration is also considered a potentially useful biomarker for predicting outcomes in patients with cardiovascular disease [12]. A number of stimuli induce sST2 gene expression, such as LPS, allergens [1], and cytokines [13]. Besides fibroblasts, sST2 is also expressed by endothelial, epithelial, and activated immune cells however it is difficult to ascertain the precise cellular source of circulating sST2 in vivo [14].

The mLN were shown to induce a prominent Th2 immune response by p

The mLN were shown to induce a prominent Th2 immune response by producing IL-4 and TGF-β, whereas pLN produced a stronger Th1 response via cytokines such as IFN-γ 22. LNtx from Ag-tolerant mice were removed and mRNA was isolated to determine the expression pattern of Th1 and Th2 cytokines. mRNA expression of IFN-γ (Fig. 5A) or IL-12 (data not shown), as examples for Th1 responses, was found in OVA-treated and untreated mLNtx-transplanted animals on a marginal expression

level, whereas OVA-treated pLNtx mice showed increased frequency compared to mLNtx. The expression of Th2-specific cytokine mRNA, including IL-4, was detected to be higher in mLNtx compared to pLNtx in Ag-tolerant mice (Fig. 5A) as well as in control mLNtx and pLNtx animals (data not shown). Furthermore, cytokines were shown to manipulate B-cell class switching from IgM to other Ig isotypes. Therefore, the serum of Ag-tolerant transplanted mice for Ig subclasses was analyzed and in pLNtx high levels of λ light chain Ab were found in the serum, whereas in mLNtx or mLN control no Ab production was detectable (Fig. 5B). In addition, in Ag-tolerant pLNtx mice increased mRNA levels of the B-cell-activating factor (BAFF) were seen compared to mLNtx Ag-tolerant (Fig. 5C)

and also to pLNtx-control mice (data not shown). These results suggest an Ig class switch and thereby BKM120 in vitro a production of one specific Ab clone in pLNtx animals. Furthermore, increased IgG3

were found in pLNtx Ag-tolerant mice compared to mLNtx (Fig. 5B). Analyzing the serum for OVA-specific Ab, high amounts of Ag-specific IgG3 Ab were verifiable only in pLNtx animals (Fig. 5D). Nevertheless, these data showed that within pLNtx an antibody induction after tolerance induction took place. By contrast, the mLNtx followed normal tolerance induction including Treg activation. Taken together, these data VAV2 suggested a dominant role of B cells in the induction of tolerance induced by pLN. To examine these findings adoptive transfer experiments were performed. Therefore, CD4+ and IgG+ cells were isolated from untreated LN as control, pLN-pt as well as mLN-ot animals after tolerance induction. These isolated cells were injected into wt mice and 20 days later the DTH response was measured. Animals with IgG+ cells of pLN-pt mice showed a high reduction in the DTH response compared to the control and mLN-ot IgG group (Fig. 6). However, mice that received CD4+ cells of untreated control LN were not able to induce tolerance, whereas mice that contained CD4+ cells of mLN-ot showed a reduced DTH response (Fig. 6). Furthermore, the reduction of the DTH response was less pronounced in mice with CD4+ cells transferred from pLN-pt mice (Fig. 6). Therefore, these adoptive transfer experiments showed the ability of pLN to induce tolerance systemically, not only by Treg activation but predominantly by B-cell class switch and Ab production.

This case suggesting that dysregulation of the alternative comple

This case suggesting that dysregulation of the alternative complement pathway within the transplant kidney may have contributed to the severe AMR. Very little is known about the impact of complement dysregulation and the development of anti HLA antibodies however the strength of HLA antibody formation was prominent in this case. Atypical

haemolytic uremic syndrome (aHUS) is a rare disease characterized by activation and dysregulation of the alternative complement pathway resulting in microangiopathic haemolytic anaemia, thrombocytopenia and microvascular occlusion causing organ impairment. The laboratory abnormalities may include an abnormal peripheral blood smear with schistocytes, reticulocytosis and thrombocytopenia; elevated creatinine and serum lactate dehydrogenase (LDH).[1] PFT�� order The identification of case clusters within families give biological plausibility to a genetic predisposition coupled with an inciting event such as sepsis or pregnancy.[1] In 40–60% of cases there is a mutation in genes encoding for regulatory proteins of the alternative complement pathway (including membrane cofactor protein (CD46/MCP), Factor H (CFH) and Factor I (CFI), Factor H related proteins (CFHR1-5), C3,

complement factor B and thrombomodulin).[1] Therefore, when the complement system is activated, these genetic defects of the regulatory proteins are associated with defective protection of the see more endothelial cell surface. More C3b reaches the cell surface leading to higher levels of terminal complement activation, with further endothelial injury, ongoing stimulation of the coagulation cascade and thrombotic microangiopathy results. Among patients with end-stage kidney disease (ESKD) secondary to aHUS referred for transplantation, the rate of recurrence of disease is 50%. Recurrent disease usually occurs early post transplant and is associated with a high rate of graft Glutamate dehydrogenase loss.

The rate of disease recurrence depends to some extent on the nature of the mutation with those involving the circulating factors CFH and CFI more likely to cause recurrent disease.[2] The lower rate of recurrence of MCP associated disease may be explained in part, by the finding that MCP is highly expressed in the kidney and allograft transplantation should restore near normal levels. Complement also has an important role in the pathogenesis of antibody-mediated rejection (ABMR) with initiation of the classical complement pathway by alloantibody, activation of C3 and subsequent graft injury mediated by C5b-9 membrane attack complex. We present a case of an unsensitized patient with ESKD secondary to aHUS with mutations in CD46/MCP (104G>A) and CFH (3590T>C) who developed unexpected, severe and intractable ABMR post transplant suggesting that the dysregulation of the alternative complement pathway may have been a contributing factor.

Renal transplant recipients are at high risk of developing SCC, a

Renal transplant recipients are at high risk of developing SCC, and the management of patients with a high tumour burden is challenging and is in need for new therapeutic approaches. The re-education of the immune system of

a tumour patient using a moDC-based vaccination strategy where these cells present tumour-specific antigens in order to induce a potent antitumour immune response is one possible individualized therapeutic modality. The successful outcome of moDC vaccination depends on many factors, including the quality of the patient’s moDC. In the present study, we therefore analysed the possibility to generate moDC from RTR with and without previous Small molecule library research buy SCC to evaluate the future possibility of applying a moDC-based vaccine for SCC treatment in RTR. The number of PBMC was slightly reduced in RTR with previous SCC (Fig. 1), which might be due to the reported CD4 lymphocytopenia in these patients [27]. In addition, we could previously show that the number of circulating plasmacytoid DC (pDC) but not type 1 myeloid DC (mDC1) is significantly reduced in RTR [17]. The efficiency of moDC generation concerning the number of cells was

not impaired in immunosuppressed patients. Regarding the phenotype and cytokine/chemokine profile, we found that the moDC from RTR are similar to those from immunocompetent controls despite some statistically significant differences, which is in line with a previous report [20]. However, the functional consequences of the slightly reduced see more CD86 expression PTK6 on moDC from immunosuppressed patients (Fig. 2) need further investigation.

Moreover, moDC from patients with previous SCC showed some alterations in their cytokine/chemokine profile compared with immunocompetent controls (Fig. 3). In particular, we observed an increased secretion of IL-1RA, MIP-1α and RANTES. Interestingly, when grouping the patients according to their immunosuppressive medication, we discovered a significant increase in IL-8 production by moDC from patients on prednisolone and cyclosporin A. However, more analyses including the functional consequence of this increase in both pro- and anti-inflammatory mediators are required. Analyses using peripheral blood DC populations revealed an altered phenotype of myeloid DC (mDC) in immunosuppressed patients [19, 20]. The cytokine production of mDC, however, has been reported to be similar in immunosuppressed patients and immunocompetent controls [20], while circulating pDC in RTR showed a deficiency to produce IFN-α upon TLR7 and TLR9 stimulation [21]. Functional analyses using both mDC and moDC from immunosuppressed patients revealed a similar T cell stimulatory capacity of these cells compared with cells from immunocompetent controls [19, 20, 23].

However, no significant changes have been detected in LX biosynth

However, no significant changes have been detected in LX biosynthesis in other chronic inflammatory diseases such as COPD [38, 39]; thus, general conclusions cannot be drawn and lipoxin receptor levels may be specific for each disease condition. Although the well-documented beneficial actions reported for LXs are suggested to involve FPR2/ALX-triggered signalling, the

specific associated pathways responsible for in-vivo lipoxin activity remain to be elucidated. In addition, data supporting a role for LXs in modulating human neutrophil function BMS-777607 in an IL-8 environment is missing, although moderate efficacy has been shown on human neutrophil transmigration across the intestinal epithelium and on the blockade of the release of human neutrophil azurophilic granules [40, 41]. The reported binding data indicate that FPR2/ALX is a high-affinity receptor for LXs and its analogues [12], but in our study the signalling activated by LXs– FPR2/ALX interactions are not the

classical G-protein-activated pathways involving an increase in GTPγ binding response, a decrease in cAMP or enhancement of the intracellular calcium flux. However, in the same FPR2/ALX recombinant cells the peptide ligand WKYMVm and the small molecule FPR2/ALX agonist compound 43 induced GTPγ binding and calcium influx, suggesting that proinflammatory peptides and synthetic FPR2/ALX compounds present agonist properties whereas, in principle, 15-epi-LXA4 binds but not acts as an FPR2/ALX agonist. Similarly, recent

work from an independent group has shown lack of signalling induced by 15-epi-LXA4 through enhancement in intracellular Reverse transcriptase calcium in FPR2/ALX over-expressing cells [32]. Conversely, a novel lipid-mediated downstream FPR2/ALX signalling has been described, involving intracellular polyisoprenyl phosphate remodelling. Interaction of these endogenous lipids with FPR2/ALX block agonist-induced presqualene diphosphate (PSDP) turnover to presqualene monophosphate (PSMP) and an increase in PSDP accentuates anti-inflammatory actions through inhibition of PLD and PI3K in human neutrophils [42, 43]. Nevertheless, the role for these pathways in FPR2/ALX-associated functions in vivo remains to be elucidated. In addition to reducing acute inflammation induced by the potent neutrophil chemoattractant LTB4, LXs are able to modulate neutrophil functions induced by proinflammatory FPR2/ALX peptides. It has been reported that LXs reverse both neutrophil chemotaxis induced by MHC- and MMK-1-derived peptides [44] and neutrophil apoptosis arrest mediated by SAA [23].