DAPI (Invitrogen) was used at 300 nM to identify cellular nuclei. Sections were mounted by using Fluorogel (Electron Microscopy Services). selleck chemicals All sections were imaged using either a Nikon Eclipse 80i microscope or an Olympus BX-51

microscope. Three TBI animals were analyzed and at least five sections per animal were analyzed. For gene expression profiling of macrophages from YARG mice, Arg1+ (YFP+ CD45hi CD11b+ Ly6G− SYTOX Blue−) and Arg1− macrophages (YFP− CD45hi CD11b+ Ly6G− SYTOX Blue−) were isolated by flow cytometry from ipsilateral brain hemispheres at day 1 following TBI (n = 4 for each cell sample). Monocytes (CD11b+ F4/80+) from peripheral blood were also collected. Sorted cells were immediately lysed in denaturation buffer and frozen. RNA was isolated by using an RNAqueous Micro kit (Ambion). Further sample preparation, labeling, and array hybridizations were performed according to standard protocols from the UCSF Shared Microarray Core Facilities and Agilent Technologies. RNA quality was assessed using a Pico Chip on an Agilent 2100 Bioanalyzer (Agilent Technologies), and RNA was amplified by use of a whole transcriptome

amplification kit (Sigma-Aldrich). Ceritinib datasheet Subsequent Cy3-CTP labeling was performed by using a NimbleGen one-color labeling kit (Roche-NimbleGen, Inc.). The quality of the amplified products was assessed by using an Agilent 2100 Bioanalyzer and Nanodrop ND-8000 (Nanodrop Technologies, Inc.). Fossariinae The products were hybridized to Agilent whole mouse genome 4×44K microarrays according to the manufacturer’s protocol. Arrays were scanned with an Agilent microarray scanner, and raw signal intensities were extracted with Feature Extraction v10.5 software. Data were normalized by using the quantile normalization method [54]. No background subtraction was performed,

and the median feature pixel intensity was used as the raw signal before normalization. A one-way ANOVA linear model was fitted to the comparison to estimate the false discovery rate for each gene for the comparison of interest, and genes with a false discovery rate < 0.05 were considered significant. Scatter plots compared averaged log2 gene expression from each group. PCA was performed using the top 15% of genes exhibiting the most variance across all samples, using the PopulationDistances module of GenePattern (PMID: 16642009). For heatmaps, data were log2 transformed and median centered across genes. Replicates were hierarchically clustered (PMID: 16939791). Heatmaps of genes selected from the top 15% most variable genes that exhibited interesting pairwise comparisons were visualized using Java Treeview (http://sourceforge.net/projects/jtreeview/files/) (PMID: 15180930). Meta-analysis of transcriptional responses of brain wound macrophages to BMDMs stimulated by either IFN-γ or IL-4 was performed using previously published tables [38].

Clinical scores were analysed using the non-parametric Mann–Whitney U-test. The level of significance was set at P < 0·05. EAE was induced in C57BL/6 mice by immunization with the MOG35–55 peptide in CFA followed by i.v. injection of PT. EAE mice exhibited three disease phases: preclinical, peak and remission phases. BAY 73-4506 research buy Clinical signs (partial limp tail) presented at 7 dpi. Disease

then progressed to limp tail, waddling gait and paralysis during the peak phases (at 16 dpi). Finally, mice recovered but still presented with clinical signs during the remission phases (at 28 dpi). CFA mice showed no clinical signs at all (Fig. 1a). Lymph node MNCs were isolated from 7 dpi EAE and CFA mice and then co-cultured with astrocytes at lymphocyte : astrocyte ratios of 10:1, 1:1, and 1:5. At the lymphocyte : astrocyte ratios tested there were no differences in proliferation among cells isolated from the CFA group, with the exception of CD3/CD28 and concanavalin A (ConA)-stimulated cells (Fig. 1b). Conversely, lymphocytes isolated

from EAE mice proliferated significantly in response to stimulation with MOG35–55 peptide (P < 0·001). In the EAE lymphocyte : astrocyte co-cultured group, lymphocyte proliferation was inhibited by half at a ratio of 10:1 (P < 0·01) and inhibited completely at ratios of 1:1 and 1:5 (P < 0·001) compared to proliferation observed for MOG35–55 peptide-stimulated EAE lymphocytes alone. These data indicate that the inhibitory effect of astrocytes on MOG35–55-specific lymphocytes is correlated with lymphocyte : astrocyte ratios. Lymphocytes were then co-cultured with astrocytes selleck compound at a lymphocyte : astrocyte Bcl-w ratio of 10 : 1. Supernatants were obtained 72 h later and cytokine levels were detected by ELISA. In the supernatants collected from EAE lymphocyte : astrocyte cultures, IFN-γ (P < 0·001) and IL-17 (P < 0·001) levels were decreased significantly; IL-4 and TGF-β levels were also decreased compared to levels observed for EAE lymphocytes. There were no significant differences in cytokine production by cells harvested from mice

in the CFA groups. Levels of the above cytokines were lower in the supernatants of astrocytes cultured alone (Fig. 1c). The suppressing effect of astrocyte on MOG35–55-specific lymphocytes might be mediated by soluble factors as well as cell contact. We cultured astrocyte and MOG35–55-specific lymphocytes without contact between both cells using Transwell plates. Supernatants were taken out to test cytokine levels after 72 h. Results are shown in Fig. 1d. Significant reductions of IFN-γ (P < 0·001) and IL-17 (P < 0·001) levels were also observed at the co-culture group without contact between both cells. These results suggest that cell contact is not required in astrocyte-mediated suppression of lymphocyte secreting, and might be mediated by soluble factors. Astrocytes were incubated in the presence or absence of IFN-γ and then co-cultured with lymphocytes for 72 h.

Therefore, it was possible that PL2-3 IC elicited a strong TLR9 signal not easily regulated by FcγRIIB. Although TLR9-expressing AM14 cells respond more robustly to DNA fragments enriched for CG dinucleotides than to CG-poor DNA fragments 14, 25, CG-poor DNA fragments can still be bound by TLR9 26. To extend our analysis

to weak TLR9 ligands, normally incapable of promoting AM14 MK-8669 datasheet cell cycle entry, we decided to use IC that contained defined dsDNA fragments derived from CG-poor portions of the genome. CG-poor dsDNA is the prevalent class of DNA found in the mammalian genome, and representative sequences such as sentrin-specific peptidase 1 (SenP1), a 557 fragment containing only four CG dinucleotides routinely induce minimal activation of AM14 B cells 14. CGneg, a sequence completely devoid of CG dinucleotides, was constructed to examine TLR9 specificity, and also fails to promote AM14 B-cell proliferation 11. By contrast, Clone 11 is a 573 bp long dsDNA fragment corresponding to a CG-rich unmethylated sequence found in the promoter region of the murine preribosomal RNA gene complex. Such CG-rich regions, denoted CpG islands, comprise about 2% of the mammalian genome 27. IgG2a IC incorporating Clone 11 are potent activators of AM14 B cells 14. To determine whether IC containing CG-poor

dsDNA fragments could SB203580 activate R2− AM14 B cells, we used IC consisting of 1D4 bound to Bio-SenP1 or Bio-CGneg. As a control for CG-rich DNA, we used 1D4 bound to Bio-Clone 11 IC. Similar to the results obtained with PL2-3, Clone 11 IC-activated R2+ and R2− AM14 B cells had almost identical dose–response curves. However, the R2− AM14 B cells proliferated significantly better than the R2+ AM14 B cells when stimulated with SenP1 or CGneg IC (Fig. 3A). These results indicate that FcRIIB does indeed regulate B-cell responses to endogenous TLR9 ligands; however, its regulatory capacity is only revealed with weak TLR9 ligands. To verify that the enhanced R2− AM14 B-cell response to SenP1 IC was still TLR9-dependent,

we tested the effect of the TLR9 inhibitor, oligodeoxynucleotide (ODN) INH-18, and the control (non-inhibitory) ODN, INH-48 28. The R2− AM14 B-cell responses to SenP1 IC were blocked by INH-18 but not by INH-48 (Fig. 3B). These Clomifene results demonstrate that in the absence of FcγRIIB-mediated inhibition, AM14 B cells respond to otherwise nonstimulatory DNA through a TLR9-dependent mechanism. AM14 B cells respond to RNA-containing IC through coengagement of the BCR and TLR7. TLR7-dependent AM14 B-cell responses to RNA IC are modest when compared with TLR9-dependent responses to CG-rich DNA IC, but can be significantly enhanced by addition of IFNα 18. To determine whether the absence of FcγRIIB promoted AM14 B-cell responses to RNA IC, we stimulated R2+ and R2− AM14 cells with increasing concentrations of the RNA-specific IgG2a mAb BWR4 29.

Briefly, for the last 18 h of culture, 20 μl 3H-thymidine (NEN selleck chemicals llc Life Science Products, Amsterdam, The Netherlands) at a concentration of 5μCI/ml was added. 3H-thymidine incorporation was determined by liquid scintillation counting, expressed as counts per minute (CPM) according to standard procedures. For data storage and management, Microsoft Excel (Microsoft, Redmond, WA, USA) was used. Graphic presentation was performed with GraphPad Prism version 5.00 (GraphPad Software, San Diego, CA, USA), and statistical analysis was performed

with SPSS version 15.0 (IBM, SPSS, Armonk, NY, USA). Data are shown as median with range unless stated otherwise. Data were analysed by Wilcoxon signed ranks test. Statistical significance was denoted at P < 0.05. We first investigated the expression of the four PARs at mRNA levels on freshly isolated naïve monocytes. Primers specific for PAR-1, PAR-2 and PAR-3 yielded bands of Ferroptosis inhibitor the expected respective size (Fig. 1). Only a faint band of PAR-4 amplification product was observed. Analysis of monocyte RNA without reverse transcriptase did not lead to amplification of any product, indicating that the PCR products obtained

were not due to genomic DNA contamination (data not shown). In all cases, positive control expression of β-actin at mRNA level was found. We next investigated expression of the four PARs and TF at the protein level on freshly isolated naïve CD14+ monocytes. As an example, freshly isolated naïve CD14+ monocytes showed clear expression of PAR-1, PAR-3 and PAR-4, but not of PAR-2 and TF (Fig. 2). The expression profile is representative for the other individual donors. These results support that PAR-1, PAR-3 and PAR-4 mediated cell signalling in naïve monocytes are possible. To test whether PAR- and TF expression on naïve CD14+ monocytes changed upon stimulation with possible PAR signalling molecules changed, PAR and TF expressions were evaluated in naïve CD14+ monocytes

cultured for 24 h in the presence of FVIIa, the binary TF-FVIIa complex, the binary TF-FVIIa complex with FX, FX, FXa, thrombin and as a positive control LPS. As shown in Figs. 3 and 4, both the percentage positive PAR-1, PAR-3 and PAR-4 expressing naïve monocytes and the mean fluorescence for PAR-1, PAR-3, and Oxalosuccinic acid PAR-4 were not altered. Percentage positive monocytes for medium conditions were 97% (range 4), 5.84% (range 1.1), and 99.9% (range 0.1), and 3.2% (range 2.86) for PAR-1, PAR-3 and PAR-4, respectively. The median mean fluorescence for medium conditions was 73.5 (range 1), 286.5 (range 97), 183 (range 131) and 38.2 (range 13.4) for PAR-1, PAR-3 and PAR-4, respectively. Also, TF expression was evaluated on freshly isolated monocytes, and the change in expression upon the different coagulation proteases tested. TF (3.2%; range 2.86) was hardly detectable on the freshly isolated naïve monocytes (Fig. 2E).

In contrast, circulating IgA levels in control wool lambs remained low and stable following initial larval exposure, and breed differences in circulating IgA were thus larger in control lambs. Greater responses in circulating IgA in response to transient exposure to parasite larvae in control hair lambs suggests a more robust response to this ‘natural’ vaccination protocol. IgA concentrations in hair sheep were somewhat higher than those reported for wool sheep in previous studies. Larval antigen-specific IgA production has been reported to peak between 1 and 2 weeks p.i. (42,44). However, total IgA in serum in our infected lambs continued to increase through 3 weeks

p.i. in both breeds. Previous studies have not observed higher serum IgA concentrations in resistant breeds including the Gulf BMS-777607 order coast native (40), Santa Ines (17) and Barbados Blackbelly (34) compared with susceptible wool breeds, which may indicate that St. Croix hair sheep have a novel resistance mechanism that is absent in other resistant breeds. Globule leucocytes are described as partially

de-granulated intraepithelial mast cells (45) and have been suggested to be responsible for larvae damage and expulsion within the first few days of infection. Unlike eosinophils (46,47), mast cells bind IgE (41), leading to similar co-dependency to that suggested for eosinophils buy Paclitaxel and IgA. Breed differences in abomasal globule leucocytes were not significant in this study, but levels tended to be greater in hair sheep at 27 days p.i. This result is less striking than the 15- to 40-fold increase in globule leucocytes of younger infected hair compared with wool lambs reported by Gamble and Zajac (18). However, breed differences in concentration these of globule leucocytes have been reported to be minimal by 1 year of age (3) and hence age differences probably contribute to apparent inconsistencies among studies. Associations of increased globule leucocytes with lower FEC, lower worm numbers and decreased female worm length are present in young animals (11,15,48), suggesting a role for these cells in resistance and are consistent with our favourable association of globule

leucocyte numbers with IgE in the lymph nodes and PCV at 21 days p.i. Measurement of sheep IgE was first reported by Shaw et al. (49) and Kooyman et al. (8) and several studies have shown that sheep infected with GIN have increased total and worm-antigen-specific IgE (8,12,13,50,51). Mean serum IgE levels in our lambs exceeded 60 ng/mL through 16 days p.i. in infected lambs of both hair and wool types. IgE levels were similarly elevated through the first 16 days following exposure and subsequent de-worming in control hair lambs, but were only transiently elevated in control wool lambs over the same period. These patterns suggest a similar change in circulating IgE following infection in the two breeds with a potentially more robust vaccination response in hair lambs, similar to that observed for circulating IgA.

Appropriate regulation of gut immunity thus depends upon a complex three-way interplay between host cells, commensals and pathogens, and can exert a major impact on systemic responses including allergy and autoimmunity. In the gastrointestinal (GI) tract, the immune Selleckchem ONO-4538 system is faced with the most demanding of all decision-making, with little room for error. It is imperative at all times to discriminate between, and respond correctly to, beneficial symbionts, harmless food antigens and potential pathogens [1]. There is increasing appreciation that regulatory T cells (Tregs)

play a prominent and essential role in maintaining appropriate responsiveness in the gut [2,3], actively enforcing homeostasis and preventing untoward immune responses occurring. While stimulated by specific antigens, of both self and non-self origin, Tregs can transcend antigen specificity, mediating bystander suppression in a manner likely to modify systemic immune status as suggested by the ‘hygiene hypothesis’. Recent studies have changed our perspective of commensal microbes from benign but inert passengers to active participants in both the postnatal development of mucosal immunity and in its long-term steady-state function. Germ-free mice show extensive deficiencies

in intestinal immune system development, with reduced lymphoid tissue and fewer https://www.selleckchem.com/products/Erlotinib-Hydrochloride.html lymphocytes [4]. The CD4+ T cell population is diminished, affecting T helper type 1 (Th1) cells disproportionately although, remarkably, Treg frequencies are maintained or increased in germ-free mice. These and other data have established that defined components of the gut flora can play a major role in intestinal homeostasis, including protection against gut injury and mediating oral tolerance against dietary

antigens. L-gulonolactone oxidase In mice which acquire a conventional microbiome, the immune system develops normally while maintaining a continuing dialogue with the commensal population. Here, one of the dominant roles of Tregs is to prevent exuberant responses against gut flora, with which the intestinal tract is in intimate contact. Nevertheless, how commensals communicate with cells to ensure immune homeostasis is still unclear. One critical factor in this interaction at the molecular level is the host Toll-like receptor (TLR) system, as demonstrated by spontaneous colitis in TLR-5-deficient mice [5]. Where colitis is induced experimentally (e.g. by dextran sulphate administration), the absence of TLR signalling then results in greatly aggravated pathology, again indicating that TLR-mediated recognition of commensal molecules contributes to dampening immune reactivity [6]. The requirement for TLR signalling in induction of oral tolerance to dietary antigens [7] also speaks to the bimodal participation of the TLR system in both stimulatory and regulatory arms of the immune response. Recent evidence suggests that TLR signalling can impact Treg homeostasis and that Tregs themselves express TLRs selectively.

[13, 17-19] The spermicide Nonoxynol-9, which was investigated as a potential microbicide to prevent HIV infection, was found to contribute to the development of epithelial lesions.[20] This may explain why women who used Nonoxynol-9 with increased frequency were at higher risk of HIV acquisition.[21]

However, diaphragms or cervical caps have been studied as a means of HIV prevention in women and have failed to demonstrate a protective effect.[22] In this issue of the Journal, Kaushic et al. and Hope et al. describe in further detail the role of the female genital tract epithelial lining in HIV transmission. Animal data using the rhesus macaque model suggest that the cervical mucosa is the first site of HIV infection after vaginal exposure to Simian immunodeficiency virus (SIV), LGK 974 and HIV-infected cells are not present in the vaginal mucosa until infection has become systemic. Zhang et al.[23] showed that cervical cells were detectably infected with SIV by day 3, whereas the vaginal mucosa was not infected until day 12, coinciding with systemic dissemination. However, there are data from animal models that

do not support the importance of the cervix in acquiring HIV.[24] Unlike the study conducted by Zhang et al. described above, Miller et al.[25] found SIV-infected cells soon after infection both in the cervix and in the stratified squamous epithelium of the vagina. Dendritic cells in the vaginal epithelium are thought to have been important in early HIV uptake in this model. We first INK 128 order Obatoclax Mesylate (GX15-070) review studies that found

cervical ectopy to be a significant risk factor for HIV acquisition, and then studies that did not find such an association (see Table 1). Moss and colleagues studying 70 HIV-infected men and their female spouses in Nairobi, Kenya found that cervical ectopy was a major predictor of HIV seropositivity (adjusted odds ratio, AOR: 5.0, P = 0.007).[26] Another study conducted among 97 female spouses of HIV-infected men in Nairobi, Kenya found that cervical ectopy was associated with cervical HIV shedding (AOR: 5.0, 95% CI: 1.5–16.9), suggesting its importance in the secondary transmission of HIV.[27] Of note, these women also had concurrently high rates of other STIs, namely N. gonorrhoeae and syphilis. In one of the few analyses to assess HIV incidence, Plourde and colleagues found that among a cohort of 81 Kenyan women with genital ulcers, cervical ectopy increased the risk of acquiring HIV (relative risk, RR: 4.9, 95% CI: 1.5–15.6).[28] However, no women without ulcers were examined so these results could suggest that cervical ectopy is a risk for ulcerative infections or that ulcerative infections of the columnar epithelium make the tissue more vulnerable to HIV.

[12] Strains of R. arrhizus have received much attention in connection RAD001 with the decomposition of biodegradable plastics.[13] Since the description of Rhizopus arrhizus by Fischer [14] in 1892 numerous species have been described in Rhizopus differing slightly in morphology, intensity of sporulation, temperature tolerance, or substrate choice.[15] After a comprehensive study of morphological features, temperature tolerance and mating, Schipper [15] synonymized 29 species with Rhizopus arrhizus (as R. oryzae). Nearly at the same time Ellis [16] concluded conspecifity of R. arrhizus, Amylomyces rouxii

and R. delemar based on DNA renaturation experiments and proposed to accommodate them in three varieties. In their monograph on the genus Rhizopus Zheng et al. [17] Selleckchem 5-Fluoracil maintained the varieties arrhizus and delemar

and introduced the new variety tonkinensis. In a molecular phylogenetic study linked to this monograph, Liu et al. [18] used internal transcribed spacer (ITS) and the pyrG gene encoding the orotidine 5′-monophosphate decarboxylase. Their data supported only the var. arrhizus and var. delemar, while strains of the var. tonkinensis were not included in the trees. In the same year Abe et al. [19] showed by multi-locus studies of four different markers that the varieties arrhizus and delemar represent two phylogenetic species differing in their production the of organic acids. As consequence the authors treated

the fumaric-malic acid producing R. delemar as a separate species from the lactic acid producing R. arrhizus (as R. oryzae). Var. tonkinensis was individualized in the molecular phylogenetic analyses of Abe et al. [19] and as a consequence it was synonymized with R. arrhizus (as R. oryzae). Gryganskyi et al. [20] analyzed the two species distinguished by Abe et al. [19] by molecular phylogeny based on additional markers including mating type genes. It was noted that ITS distances between R. arrhizus and R. delemar were very small compared to the remaining Rhizopus species, and there were no compensatory base changes (CBC) in the ITS region as indication of separate species.[20] In addition, zygospore formation between strains of R. arrhizus and R. delemar as observed by Schipper [15] was confirmed. There are no significant morphological, ecological, clinical and epidemiological differences known between the two species. Therefore the aim of the present study was to evaluate phylogenetic and biological species boundaries in R. arrhizus and close relatives, based on an extended set of strains. For that purpose mating tests, multi-locus studies, amplified fragment length polymorphism (AFLP) profiling and analyses of physiological parameters such as cardinal growth temperatures and enzyme spectra were performed. The results of Abe et al. [19] and Gryganskyi et al. [20] show clearly that R.

This concept is of fundamental importance for understanding immunological tolerance, since it implies that the distinct shape of selleck kinase inhibitor MHC-II complexes formed by truncated two-domain structures may provide a natural tolerogen for regulating inflammatory T cells selected

originally on four-domain structures. We have characterized specific interactions of both RTL1000 and four-domain DR2–MOG-35-55 with the cognate TCR present on the H2-1 T-cell hybridoma. The ability of defined TCR to bind these two TCRL-distinguished conformational MHC-II complexes highlights the permissive nature of the TCR as compared with our TCRL Fabs. The basis for the distinct specificity can be explained by major feature differences between cell surface TCRs and soluble Abs. Monomeric TCR affinities (in the range of 1–50 μM 40) are in orders of magnitude lower than our isolated TCRLs. However, in the cellular context, TCR functional avidity is defined by multiple factors such as receptor and co-receptor densities and affinities. Replacement of TCR with high-affinity TCRL-Ab results in loss of specificity of the engineered Selleckchem MAPK inhibitor T lymphocytes (Oren, R et al., manuscript in preparation), supporting the theory of maximal TCR affinity threshold for improved T-cell

function 41 and emphasizing the limitations of TCR mimics in an Ab form. An alternative explanation for these distinct specificities is that TCRL-Fab

recognition of RTLs may require a structural motif that is exposed to the solvent only when the Ig-fold domains of the four-domain MHC molecule are removed. In this scenario, TCRs originally selected on four-domain MHC complexes are not educated to recognize this unexposed motif in the four-domain molecule. Unlike TCRs, B-cell-secreted Abs potentially can discern two- versus four-domain MHC-II–peptide complexes similar to our phage-display Abs. We detected serum non-neutralizing Abs to RTLs in RTL immunized mice 22 and in MS patients (Arthur Vandenbark, personal communication). We predict that such Abs will not cross-react with native four-domain MHC-II complexes due to self-tolerance mechanisms and Flavopiridol (Alvocidib) their diverse conformation. The naïve human phage display library origin of our isolated TCRL Fabs implies their possible existence in the native Ab sequence repertoire. However, to the best of our knowledge there is no evidence for the B-cell expression of TCRL-Abs. The need to break self-tolerance and the predicted immunomodulation effect of circulating Abs specific for self-MHC–peptide complexes are possible explanations for our prediction that such Abs are not produced. While the genetic information for such Abs exists in the germ line they are not produced or are negatively selected.

This study was supported by the Medical Society of Göteborg, FoU Västra Götaland, Gunnar Nilsson

Cancer Foundation, the Swedish Cancer Society and the Swedish Medical Society. The authors declare no conflict of interest. “
“Farnesyl pyrophosphate synthase (FPPS)-catalysed isoprenoid intermediates are important for the activation of Ras homologue gene family, member A (RhoA) in angiotensin (Ang) II-induced cardiac fibrosis. This study was designed to investigate the specific role of FPPS in the development of cardiac fibrosis. We demonstrated that FPPS expression was elevated in both in-vivo and in-vitro models of Ang II-mediated cardiac fibrosis. FPPS inhibition by zolendronate and FPPS knock-down by a silencing Galunisertib price lentivirus decreased the expression of cardiac fibrosis marker genes, including collagen I, collagen III and transforming growth factor (TGF)-β1. FPPS inhibition was reversed by geranylgeraniol Lapatinib in vivo (GGOH) and mimicked by RhoA knock-down with siRhoA. The antagonistic effect of GGOH on the zolendronate-mediated modulation of RhoA activation in Ang II-stimulated cardiac fibroblasts was demonstrated by a pull-down assay. Furthermore, FPPS knock-down also prevented RhoA activation by Ang II in vitro. In conclusion, FPPS and RhoA may be part of a signalling pathway that plays an important role in Ang II-induced cardiac fibrosis in vitro. “
“Post-transplantation

lymphoproliferative disorders (PTLD) are life-threatening complications of organ transplantation caused by EBV infection and the use of chronic immunosuppression. While T-cell impairment is known

to play a critical role in the immunopathogenesis of EBV complications post-transplantation, the role of NK cells is still under investigation. Here, we have characterized NK-cell phenotype and function in peripheral HSP90 blood from asymptomatic pediatric thoracic transplant patients, patients with PTLD, and healthy controls. Overall, asymptomatic pediatric solid organ transplant (Tx) patients presented significant expansion of the CD56brightCD16± subset and displayed effective NK-cell function, while PTLD patients accumulated CD56dimCD16− and CD56−CD16+ NK-cell subsets. In addition, NK cells from PTLD patients down-regulated NKp46 and NKG2D, and significantly up-regulated PD-1. These phenotypic changes were associated with NK functional impairment, resembling cellular exhaustion. Disrupting PD-1 inhibitory pathway improved IFN-γ release, but did not enhance cytotoxicity in PTLD patients, suggesting that these defects were partially PD-1 independent. Our results indicate the important role of NK cells during EBV surveillance post-transplantation, with implications for the immunopathogenesis of EBV complications, and suggest that monitoring NK cells in transplant patients may hold clinical value.