A carbohydrate antigen specific to the larvae of the sheep nematode T. colubriformis was recognized by mucus antibodies of immune sheep, and passive-transfer experiments using IgG against this antigen indicate that it may be a target of protective immunity (93). Also, an anti-pathogenesis vaccine is being developed against the glycosylphosphatidylinositol (GPI) molecule of Plasmodium falciparum; when the synthetic carbohydrate was conjugated to a protein

carrier (keyhole limpet haemocyanin) and used to immunize mice, IgG specific for the native glycan were induced. While parasite numbers were not reduced in this model, mice were protected from severe malaria (94); further data indicate BVD-523 research buy that anti-GPI antibodies convey a similar mode of protection in humans (95). Similarly, a RXDX-106 molecular weight Leishmania carbohydrate antigen and vaccine candidate was synthesized, linked to a protein carrier and loaded onto virosomes

to increase its antigenicity (96). When mice were immunized with this construct, specific IgG1 was produced which bound to the parasite surface. These studies indicate that with the discovery of the right parasite glycan structures, immunization with synthetic forms is capable of inducing IgG, which can have a protective in vivo effect. Schistosomes induce a profound anti-carbohydrate response, primarily against the most Thalidomide abundant glycoconjugates present on the surface and secreted products of the different developmental stages (62,85). Thus, glycomics is currently a vibrant area of schistosome research, and many unique glycans have been found decorating the schistosome surface – although the entire glycome is far from complete (60). Some researchers consider the most abundant schistosome glycans, which are also highly immunogenic, to be important vaccine candidates (62,92). Adding weight to this argument is the observation that the protective antibody response produced after vaccination with radiation-attenuated

cercariae is predominantly against carbohydrates (97), and in vitro experiments show that an antibody against one of the most abundant surface glycans, lacdiNAc (LDN), can induce complement-mediated killing of newly transformed schistosomula (62). Despite this, others have proposed that this anti-glycan response is not in fact protective and that these abundant carbohydrates may function as evasive tools to divert and modulate the immune response (78,97). There are also conflicting reports on the importance of one glycan structure in vaccine-induced protection against H. contortus. One study found that IgG levels against a fucosylated form of LDN (LDNF), also present on schistosome antigens, correlated with protection against H. contortus with native secreted proteins (98).

Treatment with hCDR1 down-regulated the expression of the latter molecule.51 Our present results, as well as previous data, indicate that treatment with hCDR1 affects a number of cell types and pathways. Figure 8 summarizes schematically our updated knowledge on the effects of treatment of SLE-affected mice with hCDR1 on T and B cells. As illustrated in the Fig. 8, the expression of CD74/CD44 complex in B cells of the treated mice is down-regulated along with down-regulation of the ligand of this complex, MIF, which results in suppressed expression of survival molecules, (e.g. Bcl-xL). Previous studies suggested

that suppression of NF-κB signalling mediated the latter,17,19 in agreement with our findings following down-regulation of selleck screening library BAFF in the hCDR1-treated mice.16 In addition to the inhibitory effect of hCDR1 on the state of activation of B cells,8 the resultant enhancement of B-cell apoptosis may lead to the reduced production of dsDNA specific autoantibodies. In the T-cell compartment, however, hCDR1 induced CD4 and CD8 regulatory T cells,6,7 up-regulated the expression of Bcl-xL, and led to decreased rates of T-cell apoptosis and inhibition of T-cell activation.8,9 As a result, the production of pathogenic cytokines was significantly down-regulated. The reduced production of autoantibodies and pathogenic cytokines

is associated Epigenetics Compound Library in vitro with clinical amelioration of SLE manifestations. In conclusion, the present work has shown the involvement of the CD74/MIF pathway in the development of pathogenic B cells and in SLE-afflicted target organs. Moreover, treatment with the tolerogenic peptide, hCDR1, ameliorates disease manifestations, at least in part, by affecting this pathway. The authors have no financial conflicts of interest. “
“Antigen-presenting cell-associated four-domain MHC class II (MHC-II) molecules play a central role in activating

autoreactive CD4+ T cells involved in multiple sclerosis (MS) and type 1 diabetes (T1D). In contrast, two-domain MHC-II structures with the same Thymidylate synthase covalently attached self-peptide (recombinant T-cell receptor ligands (RTLs)) can regulate pathogenic CD4+ T cells and reverse clinical signs of experimental autoimmune diseases. RTL1000, which is composed of the β1α1 domains of human leukocyte antigen (HLA)-DR2 linked to the encephalitogenic human myelin oligodendrocyte glycoprotein (MOG)-35-55 peptide, was recently shown to be safe and well tolerated in a phase I clinical trial in MS. To evaluate the opposing biological effects of four- versus two-domain MHC-II structures, we screened phage Fab antibodies (Abs) for the neutralizing activity of RTL1000. Five different TCR-like Abs were identified that could distinguish between the two- versus four-domain MHC–peptide complexes while the cognate TCR was unable to make such a distinction.

[4-9] Hessell et al.[10] showed that an HIV-specific neutralizing MG-132 mw antibody mutated in the Fc position was no longer able to elicit Fc-mediated functions, such as ADCC, and that the efficacy in preventing simian/human immunodeficiency virus (SHIV) infection of macaques was significantly decreased, suggesting that the ADCC function is important for the protection afforded by neutralizing antibodies. There is a more limited understanding of the role of ADCC in the small subset of HIV-infected subjects who naturally control chronic infection, although the role

of cytotoxic T lymphocytes and neutralizing antibodies has been extensively studied.[11-24] We previously detected ADCC-mediated NK-cell activation in a small cohort of six subjects with slow HIV progression, but found no clear correlation with the magnitude of the ADCC response and control of selleck chemicals llc HIV. A recent study of 22 subjects indicated that elite controllers of HIV infection (subjects with consistent plasma HIV levels of < 50 copies/ml) have higher levels of ADCC antibodies than viraemic subjects, with an absence of correlation between cytotoxic T lymphocytes and neutralizing antibodies.[6] Whether these results are generalized across larger numbers of long-term slow-progressors

(LTSP) subjects is not clear. In addition, the HIV epitopes targeted by efficient ADCC are unknown but would logically be interesting vaccine targets. We analysed ADCC responses using an assay studying antibody-mediated interferon- γ (IFN-γ) and CD107a expression of NK cells. We

studied serum samples from 139 HIV-infected subjects not on anti-retroviral therapy; 65 subjects were LTSP who maintained a CD4 T-cell count of > 500/μl for at least 8 years after infection and the remaining 74 subjects were non-LTSP. We found that ADCC responses in LTSP subjects were broadly reactive against multiple HIV proteins and that LTSP subjects disproportionally targeted three specific ADCC epitopes within Vpu (viral protein U). The characteristics of the 139 subjects are shown in Table 1. All subjects were HIV-infected Y-27632 2HCl and not on anti-retroviral therapy at the time of sampling. Subjects enrolled in both cohorts provided written informed consent and the relevant human research ethics committees approved all studies. Subjects were recruited both through the Long-term non-progressor network co-ordinated by the Kirby Institute, Sydney, Australia and through the Melbourne Sexual Health Centre, Australia. Sixty-five of the subjects met the pre-defined criteria as LTSPs, being HIV-positive for more than 8 years without anti-retroviral therapy and maintaining a peripheral CD4+ T-cell count above 500 cells/μl. There were no viral load entry criteria. The remaining 74 subjects did not meet the criteria for LTSP (i.e. had not maintained CD4 T-cell counts > 500 cells/μl for 8 years). For both cohorts, serum for ADCC testing was derived from the earliest time-point available.

1). The use of IL-12p40-deficient mice or neutralizing Abs against IL-12p40 was among the most powerful interventions to prevent experimental autoimmunity [23]. The discovery of IL-23 and its use of the p40 subunit opened up the possibility that attributing auto-inflammatory disease initiation anti-CTLA-4 antibody to

IL-12 and Th1 cells may have been based on mistaken identity. Shortly after the discovery of IL-23, it was shown that mice lacking IL-12 (p35) were highly susceptible to experimental autoimmune encephalomyelitis (EAE), whereas IL-12/23p40-deficient mice were indeed completely resistant [24]. This observation caused a paradigm shift, and the fundamental role of IL-23 rather than IL-12 as a master regulator in autoimmune disease was confirmed when mice lacking the unique IL23p19 subunit were found to phenocopy IL-12/23p40−/− mice [25]. Contrary to IL-12, IL-23 does not induce the differentiation of IFN-γ-producing Th1 cells, but drives the expansion of a highly encephalitogenic, IL-17-producing T-cell population [26]. This was among the most exciting among a fine selection of observations made in the

long history of studying the functions AZD1208 purchase of IL-12 and IL-23 (Fig. 1), and has in itself spawned a new field of research dedicated to unraveling the regulation and function of IL-17-producing helper T cells, so called “Th17” cells. While IL-12 can be sensed by naïve cells, the complete IL-23 receptor is not expressed on their surfaces. Thus, ID-8 the factors equipping T cells with the ability to sense IL-23 became a major focus of research (reviewed in [27]). Much like the cytokines of the IL-12 family, the corresponding IL-23 receptors also share subunits that are required for the signaling of multiple cytokines. The IL-23 receptor is composed of a common

subunit, IL-12Rβ1, and a second protein unique to IL-23 signaling, IL-23Rα [28]. IL-12Rβ1 is also required for IL-12 signaling, but to date the only known function of the IL-23Rα chain is to transmit the signals of IL-23. Therefore, T cells lacking IL-12Rβ1 cannot respond to IL-12 nor IL-23. T cells lacking IL-23Rα cannot respond to IL-23, but retain IL-12 signaling capability. In the context of the widely used animal model for multiple sclerosis, EAE, deficiency of IL-12Rβ1 completely abrogates disease induction [29]. The observation that IL-12Rβ2-deficient mice are fully susceptible to EAE confirms that IL-12 signaling is dispensable for EAE induction, and the missing signals from IL-23 are responsible for the resistance seen in IL-12Rβ1 knockouts [30]. IL-23 was soon after definitively confirmed as the major pathogenic molecule in EAE, due to a requirement for IL-23 signals to drive proliferation, expansion, and survival of pathogenic T cells in the CNS [25, 31].

1A). We found that PS-5 and, at a lower extent, KIR peptide significantly reduced IFN-γRα phosphorylation. In addition, PS-5 impaired JAK2 phosphorylation, as well as STAT1 phosphorylation at the tyrosine 701 residue. In contrast, STAT1 phosphorylation at serine 727 residue, which is constitutively detected in keratinocyte cultures, was not affected either by PS-5 or KIR. As a direct consequence Selleck X-396 of STAT1 inactivation, the expression of IRF1, which is induced by

IFN-γ in late phase, was reduced in IFN-γ-activated keratinocytes treated with KIR or, more efficiently, with PS-5. We further evaluated the effect of PS-5 peptide on STAT1 transcriptional activity (Fig. 1B). To this end, keratinocyte cultures were transfected with a STAT1-responsive plasmid, pGAS-Luc, pretreated or not with the SOCS1 mimetics and then, stimulated with IFN-γ. In line with data previously described, we found

that PS-5 impaired the luciferase activity of pGAS-Luc as compared with irrelevant peptide. To evaluate the selectivity of PS-5 on JAK2 activity, we also analyzed the activation of ERK1/2, whose phosphorylation and activity are strongly induced by IFN-γ in primary cultures of keratinocytes. Interestingly, we found that PS-5 did not affect significantly ERK1/2 phosphorylation, as well as basal ERK1/2 expression (Fig. 1A). Finally, since the SOCS1 KIR domain can inhibit various molecular cascades, we evaluated the selectivity of PS-5 effects on another signaling pathway, particularly important during pathogenetic skin processes, the IL-22/STAT3 signaling Nivolumab chemical structure [8, 17]. We found that keratinocyte cultures pretreated with PS-5 had a reduced STAT3 activation in response to IL-22. However, this inhibitory effect was less pronounced than that observed Cediranib (AZD2171) for STAT1 phosphorylation, indicating a likely higher affinity of PS-5 peptido-mimetic for JAK2 than for TYK2, the kinase protein mediating IL-22 signal

[17]. As a whole, these data indicate that the SOCS1 mimetic PS-5 greatly reduces the proximal molecular cascades triggered by IFN-γ in human keratinocytes, and, specifically, those leading to STAT1 activation and function. During immune-mediated skin diseases, the exposure to IFN-γ stimulates the epidermal keratinocytes to produce inflammatory mediators, such as membrane molecules, cytokines, and chemokines, which actively participate to the amplification of the local pathogenetic processes [18, 19]. Due to limited existing information on the IFN-γ-dependent transcriptional regulation of these mediators in human keratinocytes, we firstly identified the inflammatory genes whose expression is strictly dependent on STAT1 activity. To this end, we transfected keratinocyte cultures with specific STAT1 siRNA molecules and evaluated the consequence of STAT1 knockdown on the expression of ICAM-1 and HLA-DR membrane molecules in IFN-γ-activated or resting cells.

Splenocytes were fixed and permeabilized using the FoxP3 staining buffer Ibrutinib manufacturer set (eBioscience, Inc., San Diego, CA), and were then incubated with anti-Bcl-2

or anti-Bcl-xL (Cell Signaling Technology, Danvers, MA). Cells that had undergone apoptosis were detected by flow cytometry using an FITC-annexin V antibody and annexin V staining solution (BioLegend), according to the manufacturer’s instructions. Flow cytometry analyses were performed using a FACS Canto flow cytometer (Becton Dickinson, Franklin Lakes, NJ). The data were analysed using FlowJo software (Tree Star Inc., Ashland, OR). The proliferation rate of T lymphocytes in control and Stat3-deficient mice was measured by in vivo bromodeoxyuridine (BrdU) incorporation assay, as described previously.[21] Briefly, 2 mg BrdU solution (BD Pharmingen, San Diego, CA) in PBS was injected intraperitoneally into control (Stat3fl/fl Lck-CRE−/−) and Stat3-deficient (Stat3fl/fl Lck-CRE+/−) Vemurafenib price mice. Twelve hours after injection, splenocytes were isolated from both groups of mice. Purified splenocytes were stained with the allophycocyanin-anti-mouse CD3 antibody (BioLegend). Next, the cells were fixed and permeabilized using a FoxP3 intracellular staining kit (eBioscience), and then labelled with an FITC-conjugated anti-BrdU antibody using a BrdU Flow Kit (BD Pharmingen), according to the manufacturer’s instructions. Flow cytometry analyses

were conducted on a FACSCanto flow cytometer. The data were analysed using FlowJo software. Splenic T cells were enriched using a Pan T-cell Isolation Kit (Miltenyi Biotech Inc., Auburn, CA) according to the manufacturer’s instructions. Briefly, non-T cells in a cell suspension from the spleen were magnetically labelled. Then, non-T cells were removed by magnetic selection with an autoMACS Separator (Miltenyi Biotech Inc.). Isolated splenic T-cell purity was over 97% (data not shown). Isolated thymocytes or splenic cells were harvested in a lysis solution (Santa Cruz Biotechnology, Santa Cruz, CA) containing a protease

inhibitor cocktail (Roche, Basel, Switzerland) and a phosphatase inhibitor (Santa Cruz Biotechnology). Total protein samples were separated by SDS–PAGE and transferred to nitrocellulose membranes (GE Healthcare, FER Pittsburgh, PA). The membranes were then probed with antibodies against Stat3, Bcl-2, Bcl-xL, cleaved caspase-3, or β-actin (Cell Signalling Technology) and visualized using SuperSignal West Femto Chemiluminescent Substrate (Thermo Fisher Scientific, Fremont, CA). Total RNA was purified from isolated spleen cells using the RNeasy Plus kit (Qiagen GmbH, Hilden, Germany) and cDNA was synthesized using a QuantiTech Reverse Transcription Kit (Qiagen). Then, cDNA was mixed with QuantiFast SYBR Green PCR master mix (Qiagen) and specific primers. Quantitative reverse transcription-PCR was performed with an Applied Biosystems 7300 Real-Time PCR System (Life Technologies, Carlsbad, CA). Raw data were analysed by comparative Ct quantification.

In autoimmunity, altered T lymphocyte responses are observed [3,4]. Enhanced T cell antigen receptor

(TCR) signalling and immune complexes (ICs) contribute to the disease pathogenesis in systemic lupus erythematosus (SLE) [5]. ICs bind to its ligand, the low-affinity FcγRIIIA membrane receptor, which induces phosphorylation of the FcRγ chain, the signalling subunit for FcγRIIIA. The FcRγ chain mediates signalling via immunoreceptor tyrosine-based activation motif (ITAM), which upon phosphorylation recruits Syk in B cells and platelets. Syk-mediated signalling is an important event for B cell activation [6]. Interestingly, FcRγ chain in T cells associates with the ζ-chain, forming heterodimers in the TCR complex, and the FcRγ chain is able to support independently the development of the peripheral T cells in mice lacking endogenous TCR ζ-chain [7]. The FcRγ chain containing TCR complexes Volasertib mw are present in activated γδ+ T cells, natural killer (NK)-like T (NK T) cells, SLE T cells and in certain populations of human T effector cells [8–11]. An association of FcRγ chain with the TCR complex is also observed in TCRαβ+CD4–CD8– double-negative regulatory T cells (Tregs) [12]. In these cells, TCR ligation

results in the phosphorylation of both FcRγ chain and Syk, and this event is shown to be necessary for their suppressive activity [12]. TCR in CD4+ T effector cells show association of FcRγ chain with Syk [11]. Such events are also observed in antigen-induced arthritis (AIA), a chronic Bcr-Abl inhibitor arthritis regulated by ICs and T cells [13]. In AIA, inflammation and cartilage erosion is dependent on FcRγ chain-mediated signalling [14]. Also, for the full development

of experimental autoimmune encephalomyelitis (EAE), expression of FcRγ chain by γδ T cells in association with the TCR/CD3 complex is required [15]. Both these diseases show elevated levels of ICs. However, the ligand that triggers the Syk phosphorylation is unknown. In this report, we show that a subset of peripheral human CD4+ T cells bind to labelled aggregated human γ-globulin (AHG). SLE patients show a two–fourfold increase in this population when compared to the normal subjects. Thus, we explored whether ICs acts as a ligand for the activation of Syk signalling pathway Thymidine kinase in CD4+ T cells via engagement of low-affinity membrane Fc receptors (FcRs). The terminal complement complex (TCC), also referred to as soluble C5b-9, is a non-cytolytic by-product of the terminal complement activation pathway that triggers proinflammatory responses, cytokine release and vascular leakage [16]. We observed that, in human CD4+ T cells, in the presence of ICs, TCC synergistically enhances the phosphorylation of Syk. In addition, cells treated with TCC or non-lytic C5b-9 demonstrated aggregation of the membrane rafts (MRs) (Fig. 5). MRs are membrane structures that are crucial for lymphocyte signalling, i.e.

, 2008); however,

such an approach relies on the a priori selection of targets, and therefore suffers from the ‘if you didn’t look for it you won’t find it’ syndrome. When the imminent threat of attack with bioterrorism weapons was realized, the Defense Advanced Research Projects Agency of the US Department of Defense initiated an urgent search for new methods for the broad detection and identification of bacteria. find more Clearly, the existing culture methods were not inclusive of all species and were too slow and cumbersome. Thus, the enemy’s selection of a pathogen that was not detected by our well-known cultural paradigms would result in a disastrous failure to diagnose. In response to this call, David Ecker’s team, at Ibis, developed a novel strategy in which the amplicons produced by PCR would be weighted by mass spectroscopy and their precise weight would be NVP-BKM120 used to calculate their base composition. To provide for the identification of all bacteria, both known and unknown, both pathogen and nonpathogen, multiple sets of primers were designed to detect multiple classes of genes, including those that are highly conserved across entire domains (e.g. 16S and 23S rRNA genes)

as well as sequences that are phylum or class specific, and others that are specific to lower taxonomic groupings. Each set of primers are designed to hybridize to a conserved region of a gene that flanks a variable region. Thus, each species that is amplified by each primer pair will produce a different amplicon that is diagnostic or partially diagnostic for that species. By collectively looking at which primers yielded any product, Org 27569 and then characterizing the weight and ultimately the base composition of all the resulting products, it is possible to precisely determine

all those individual species that were present in the specimen. This approach is extremely flexible, allowing the design of different primer sets for a range of applications such as the broad detection of all bacteria, to the much more specific surveillance of influenza strains. No sequencing is required because the base content of the specific variable regions of each amplicon provides the information necessary for making a diagnosis as the system has a look-up database that uses a complex iterative proprietary algorithm (Eckeret al., 2008) that matches the observed amplicon weights against those of all of the known bacterial pathogens (Fig. 5). If a novel bacterium is present, the system will recognize this because one or more of the amplicon weights will not correspond to any species in the database. In such a case, the system notifies the user that a new species has been identified and what its most closely related relative is.

5b): 36% of activated Treg cells expressed SD-4, with more Treg cells (53%) expressing CDK and cancer PD-1. Finally, we assayed the ability of SD-4+/+ versus SD-4−/− Treg cells to suppress T-cell activation (Fig. 6). Varying numbers of CD4+ CD25+ Treg cells purified from spleens of naive WT or KO mice were co-cultured with CFSE-labelled CD4+ CD25neg Tconv cells in the presence of anti-CD3 antibody and irradiated APC. T-cell proliferation was assayed by CFSE dilution. Without Treg cells, 60% of Tconv cells proliferated. As expected, SD-4+/+ Treg cells inhibited

this proliferation in a dose-dependent manner (down to 13% proliferation), and SD-4−/− Treg cells exhibited similar inhibitory capacity at every dose tested. These results show that SD-4 deficiency has little or no influence on Treg-cell function, thereby supporting the idea that exacerbation of GVHD by infusion of SD-4−/− T cells is primarily the result of augmented reactivity of Tconv cells to APC co-stimulation. SD-4 belongs to the SD family of transmembrane receptors heavily laden with heparan sulphate chains consisting of alternating disaccharide residues.[25] Because these heparan sulphate chains bind to a variety of proteins, including growth factors, cytokines, chemokines and extracellular matrices,[26] SD-4 can participate in a wide range of physiological and pathological

conditions. Indeed, SD-4 is known to play important roles in cell matrix-mediated and growth factor-mediated signalling

Selleck Ivacaftor events.[27] SD-4-deficient mice may appear normal, but respond to intentional wounding with delayed repair, impaired angiogenesis, and poor focal adhesion of cells to matrix.[28] SD-4 also regulates immune responses: when given endotoxin, SD-4 KO mice succumb more readily to shock than WT controls;[29] SD-4 on B cells triggers formation of dendritic processes, which facilitate these cells’ interaction with other immune cells.[30] Our studies constitute the first evidence showing SD-4 on T cells to regulate the activation of allo-reactive T cells in GVHD. All the results using SD-4 KO mice unambiguously indicate SD-4 on T cells to be the sole DC-HIL ligand responsible for mediating its T-cell-inhibitory function (SD-4−/− T cells did not Unoprostone bind DC-HIL nor did they react to DC-HIL’s inhibitory function), with one exception: DC-HIL-Fc treatment up-regulated cytokine production by SD-4−/− CD4+ T cells (compared with SD-4+/+ CD4+ T cells) following in vitro anti-CD3 stimulation (Fig. 2e). Because DC-HIL binds not only to a peptide sequence of SD-4 but also to saccharide (probably heparan sulphate or other structurally related saccharides),[6, 12] we speculate that absence of SD-4 and APC may restrict DC-HIL interaction exclusively to saccharides on T cells, thereby producing effects independent of SD-4.

This illustrates further that PID are not diseases affecting children only and that the Poziotinib nmr awareness for adult presentations of these diseases is increasing. In

some of our contributing centres, adults are treated in paediatrics departments because there is no expertise in internal medicine departments. This is an issue that certainly still needs to be given more attention from policy makers, and our observations should help to bring this issue on the agenda. The genetic basis of their disease remains undefined for a large number of patients, especially for those with antibody deficiencies. The gender distribution shows that males were affected much more frequently by PID than females. Interestingly, in patients younger than 30 years, boys are

affected more frequently even if X-linked diseases selleck chemicals are excluded. A specific example for this was recently given in autoimmune lymphoproliferative syndrome (ALPS) [20]. The reason for this is unknown, but may reflect additional genetic susceptibility factors encoded on the Y-chromosome. We further observed that among patients older than 30 years, more women than men are affected by a PID. We have no explanation for this. Another important issue is the diagnostic delay which is a marker for the improvement of awareness of PID. This is especially true in PID that present less severely and may go undiagnosed for many years, such as CVID. We were able to identify positive overall trends towards a shorter diagnosis for agammaglobulinaemias and IgG subclass deficiency. Conversely, CVID in particular continues to present with a very high median diagnostic delay of 3 years in many patients who receive Fossariinae their diagnosis more than 10 or even 20 years after disease onset. The documentation progress of the ESID database has made it the largest single collection of PID patient data to date. The more countries manage to organize a complete coverage

of PID documentation on the national level, the better we can judge the meaning of numbers produced by the ESID database. In a survey among the database users conducted from July to September 2010, we tried to determine how the system could be made more user-friendly in order to increase reporting. Major issues we identified were slow loading of the web pages and the complicated structure of the system, with more than 210 disease entities. We addressed these issues by upgrading to new hardware and restructuring the data entry system, which led to a reduction to 138 entities. Conversely, we also realized that our current core data set is obviously too complex and unfocused, because for many patients large parts remain undocumented. Therefore, we decided to define a new, more focused core data set which will be discussed by representatives of all national registries in Freiburg in December 2011.