To analyse the role of CD4+ T subsets in this protection, we took

To analyse the role of CD4+ T subsets in this protection, we took two approaches. First, we compared CD4+ T-cell activation and TCR Vβ diversity from draining LN at 1 week post-infection

with La alone versus La infection following pre-infection with Lb for 8 weeks (short-term). We focused on IFN-γ production in Vβ8, Vβ4 and Vβ6 (because of their relatively high frequencies) and used Vβ7 as an example of low-frequency types (Figure 1). Compared to La infection HSP assay alone, pre-infection with Lb increased IFN-γ production from total CD4+ T cells, as well as from Vβ6- and Vβ8-bearing CD4+ T cells (Figure 3c). Second, we compared CD4+ T-cell activation and TCR Vβ diversity from draining LN and the spleen at 1 week post-infection with La versus Lb parasites in mice that were pre-infected with Lb for 24 weeks (long-term). As shown in Figure 4(a), the secondary infection with Lb (the Lb/Lb group) consistently showed higher IFN-γ but lower IL-17 production from draining LN CD4+ T cells than did the La counterparts (the Lb/La group). For the tested Vβ-bearing CD4+ T-cell subsets (Vβ4, 6, 7, and 8), the Lb/Lb groups

displayed 2.1- to 9-fold higher frequencies of IFN-γ-producing cells in draining LNs. It was evident in Figure 4(b) that the Lb/Lb groups showed high frequencies of IFN-γ-producing cells in the tested T-cell subsets. Likewise, the similar trends were observed for cells obtained from the spleen (Figure 4c,d). Collectively, our results indicate SAR245409 mouse that repeated exposures to Lb parasites (the Lb/Lb groups) preferentially stimulate the expansion of IFN-γ-producing cells among multiple Vβ-bearing CD4+ T-cell subsets and that such responses contribute to the protection against a secondary infection with La parasites. To further characterize CD4+ T-cell activation during the primary and secondary infections, we collected draining LN cells at 4 weeks post-infection with La or Lb and stimulated cells briefly (6 h) with PMA/ionomycin, The ex vivo production of intracellular cytokines (IFN-γ, IL-10, IL-17, IL-2 and TNF-α) in CD4+ CD44+ T cells was

analysed by FACS. As shown in Figure 5(a), CD4+ CD44+ T cells from Lb-infected Quinapyramine mice contained higher frequencies of IFN-γ-producing cells, but lower frequencies of IL-10- and IL-17-producing cells than did the counterparts from La-infected mice. On average, the ratios of IFN-γ- vs. IL-10-producing cells in Lb-, La- and noninfected mice were 4.7, 2.0 and 1.7, respectively. The frequencies of IL-2- and TNF-α-producing CD4+ CD44+ T cells were comparable in two infection models. Therefore, CD4+ T cells derived from Lb-infected mice were highly activated with a strong Th1 phenotype. Next, we designed a cross-stimulation experiment, in which draining LN cells from La- or Lb-infected mice were restimulated in vitro with La or Lb antigens, and vice versa.

This finding was supported partially in man by showing that DCs i

This finding was supported partially in man by showing that DCs in H. pylori infected human gastric biopsies have a semi-mature phenotype and expressed DC-specific intercellular adhesion molecule-3-grabbing non-integrin (SIGN) [53]. In addition to this, the virulence factor vacuolating cytotoxin has also been shown to regulate DC maturation negatively [54], suggesting that the modulation of DC maturation plays an important role in H. pylori’s subversion of the immune response. The study presented here has focused on the effect of H. pylori-infected DCs on Buparlisib cost naturally occurring Tregs, and whether or not infected DCs are able to produce IL-18 and induce de-novo Tregs has not been investigated.

However, many reports published in the last few years have confirmed that H. pylori

infection induced DC maturation and the release of IL-23 [10, 13, 55-57]. In conclusion, we have found that H. pylori expands Tregs in vitro and in vivo and subverts their suppressive function through the production of IL-1β from DCs. These findings question the role of Tregs at H. pylori-infected sites and provide mechanistic and therapeutic insights into the mechanisms of H. pylori-associated chronic gastritis and potential targets for the local treatment of inflammation associated with H. pylori in patients who do not respond to standard eradication therapy. The authors acknowledge financial support from the Department of Health via the National Institute for Health Research (NIHR) comprehensive Biomedical Research Centre award to Guy’s & St Thomas’ NHS Foundation Trust in partnership selleck kinase inhibitor with King’s College London and King’s College Hospital Metalloexopeptidase NHS Foundation Trust. The authors acknowledge the support of the MRC Centre for Transplantation. This work

was funded by grants from the Medical Research Council (to B.A., P.M. and R.I.L.), the British Heart Foundation and Guy’s and St Thomas’ Charity Trust (R.I.L. and G.L.). The authors of this manuscript have no conflicts of interest to disclose. “
“Calreticulin (CRT) is a multi-functional endoplasmic reticulum protein implicated in the pathogenesis of rheumatoid arthritis (RA). The present study was undertaken to determine whether CRT was involved in angiogenesis via the activating nitric oxide (NO) signalling pathway. We explored the profile of CRT expression in RA (including serum, synovial fluid and synovial tissue). In order to investigate the role of CRT on angiogenesis, human umbilical vein endothelial cells (HUVECs) were isolated and cultured in this study for in-vitro experiments. Our results showed a significantly higher concentration of CRT in serum (5·4 ± 2·2 ng/ml) of RA patients compared to that of osteoarthritis (OA, 3·6 ± 0·9 ng/ml, P < 0·05) and healthy controls (HC, 3·7 ± 0·6 ng/ml, P < 0·05); and significantly higher CRT in synovial fluid (5·8 ± 1·2 ng/ml) of RA versus OA (3·7 ± 0·3 ng/ml, P < 0·05).

51 To date, however, outcomes of patients treated with the pubova

51 To date, however, outcomes of patients treated with the pubovaginal sling after failed MUS have not been reported. Preclinical studies in animals have suggested that autologous myoblasts and fibroblasts may be effective for regeneration of the rhabdosphincter and for reconstruction of the urethral submucosa.52–54 Intraurethral selleck chemical injection of autologous fibroblasts and myoblasts treatment has been

tested in 12 women with severe SUI due to ISD.55 After 12 months, three of these women remain dry and seven have shown improvements on the pad test, with none of these patients experiencing any adverse events related to the procedure. A comparison of the effectiveness and tolerability of injections of autologous cells with endoscopic injections of collagen for SUI showed that continence improved more

in patients injected with autologous myoblasts and fibroblasts than in those injected with collagen.56 These results indicate that cell therapy may be clinically feasible and safe, showing promising results in the management of SUI caused by ISD in patients with surgical failure. However, long-term follow-up results are needed. Although 5–20% of patients undergoing MUS develop recurrent or persistent SUI, little is known about methods to evaluate and manage these patients. Repeat MUS may be successful in patients who fail prior MUS, although data are limited to small case series with short follow-up duration.

A less invasive EGFR inhibitor procedure, such as tape shortening or periurethral injection, may be indicated for these patients. No conflict of interest have been declared by the authors. “
“Objectives: The aim of the present study was to investigate the risk factors filipin for the development of de novo stress urinary incontinence (SUI) and mixed urinary incontinence (MUI) after surgical removal of a urethral diverticulum (UD). Methods: We identified 35 consecutive women that underwent surgical removal of a UD between November 2002 and December 2009, and we retrospectively reviewed their medical records, including patient demographics, pelvic magnetic resonance imaging (MRI), presenting symptoms related to voiding, and outcomes. Results: Among the 35 patients we identified, 28 were included in the study. After UD removal, five of the 28 patients (17.8%) developed de novo MUI, and four of the 28 patients (14.2%) developed de novo SUI. The incidences of SUI and MUI were significantly higher in patients who had a UD that measured over 3 cm in diameter and in patients in whom the UD was located in the proximal urethra. Of the seven patients with a diverticulum over 3 cm, SUI occurred in three (42.8%) (P = 0.038) and MUI occurred in five (45.4%) (P < 0.001).

The collected supernatant was then recentrifuged at 8000 g for 30

The collected supernatant was then recentrifuged at 8000 g for 30 mins at 4°C. The final supernatant fluid was filtered through a 0.4–l µm filter before storage at 20°C until used in infectivity experiments. Copy number of WSSV in the supernatant fluid was calculated by competitive PCR [16, 17]. Fifty microliters of supernatant fluid containing 5.5 × 104 copy number of virus was injected i.m. into the lateral area of the fourth abdominal segment of

shrimp for challenge studies. Challenge tests were conducted in triplicate (20 shrimps per experimental group in a 120 L container for each time sampled, i.e. 20 animals × four salinities × five time intervals in triplicate). F. indicus were injected i.m. with WSSV inoculums (5.5 × 104 copy number) into the ventral sinus of the cephalothorax. After injection,

the shrimp were exposed to check details 5, 15, 25 (control) and 35 g/L salinities and monitored for pathological changes and mortality. The experiment lasted 120 hrs at 28 ± 0.5°C. Shrimp injected with equal volumes of sterile saline solution and exposed to 5, 15, 25 and 35 g/L seawater served as the unchallenged controls. Twenty healthy animals were allocated to each experimental salinity group (in triplicate–20 × 3) and injected i.m. with WSSV inoculums (5.5 × 104 copy number). After injection, the animals were exposed to varying salinities of 5, 15, 25 and 35 g/L for each assay; three WSSV-injected animals were randomly sampled from each tank at 24, 48, 72, 96 and 120 hrs pi. Hemolymph (100 µL) Sinomenine was withdrawn individually from the ventral sinus of each shrimp into a 1 mL sterile PF-01367338 order syringe (25 gauge) pre-filled with 0.9 mL anticoagulant solution (30 mM trisodium citrate, 0.34 M sodium chloride,

10 mM EDTA, 0.115 M glucose, pH 7.55, osmolality 780 mOsm/kg) and stored at −80°C in aliquots (100 µL tubes) until the hematological and immunological assays. For every assay, 100 µL of hemolymph (collected in triplicate) was used. Total protein, carbohydrate, and glucose concentrations were examined in the hemolymph of WSSV-infected shrimp. Total protein was measured spectrophotometrically (O.D. 595 nm) [17], total carbohydrate using the anthrone method [18], glucose by the glucose oxidase method [19] and total lipids using the procedure described by Folch et al. [20]. Hemolymph samples collected from each experimental and control group (three random shrimps per group × triplicate), were separated into aliquots and processed for assessment of selected immunological indices. THC (cells/mL) were performed using a Burker hemocytometer [21]. The hemocytes were analyzed by phase contrast microscopy and counted manually in all 25 squares (=0.1 mm3). PO activity was measured spectrophotometrically by recording the formation of dopachrome produced from L-DOPA [22]. The optical density of the shrimp’s phenoloxidase activity for all test conditions was expressed as dopachrome formation in 50 µL of hemolymph.

Furthermore, the iTreg cell induction protocol was modified and t

Furthermore, the iTreg cell induction protocol was modified and the cell line Colo699 was used instead of PCI-13. In all conditions, iTreg cells significantly enhanced NK cell degranulation (Fig. 3C). We also added the supernatant of anti-CD3-activated iTreg cells to NK cells to evaluate an iTreg cells derived soluble factor responsible for iTreg cell–NK cell interaction but could not detect significant effects on NK cell degranulation. Further, iTreg cells were tested negative for surface expression of potentially NK

activating NKG2D ligands, ULBP1, ULBP2, ULBP3, MICA, and MICB (data not shown). Next, we sought to identify the cytolytic Selleck 5-Fluoracil effector mechanism responsible for the increased cytotoxicity of NK cells when co-cultured with iTreg cells. To exclude that iTreg cells themselves exhibit cytotoxicity Bortezomib on tumor cells, we tested iTreg cells for the expression of perforin and FasL as well as their capacity to lyse tumor cells. iTreg cells

neither expressed perforin nor FasL nor induced tumor cell lysis when co-cultured with tumor cells (data not shown). To investigate if the observed enhanced cytotoxicity of NK cells is mediated by soluble factors, we added the supernatant of iTreg cells/NK cells co-cultures to the tumor cells but could not detect any tumor cell lysis (data not shown). These observations suggested that tumor cell lysis is mediated by a direct cell–cell interaction between NK cells and target cells; thus, we used concanamycin A (CMA) and inhibitory antibodies to block perforin-, FasL-, and TRAIL-mediated

cytotoxicity, respectively. As depicted in Fig. 4, tumoricidal activity of non-stimulated heptaminol NK cells in the absence of iTreg cells was predominantly mediated by perforin. This is illustrated by the reduction of tumor cell lysis by CMA (Fig. 4A), while inhibitory antibodies, which blocked FasL and TRAIL had no effect (Fig. 4B and C). Consistent with our data in Fig. 3, NK cells showed a significantly higher cytotoxicity towards tumor cells when they were co-cultured with iTreg cells overnight prior to the addition of 51-Cr-labeled target cells (triangles in Fig. 4A–C). This effect was significantly reduced if NK cells were pretreated with CMA or inhibitory antibodies to FasL, while anti-TRAIL antibodies had a minor or no effect (Fig. 4A–C). In summary, natural cytolytic activity of NK cells is mainly mediated by perforin, while death receptor pathways like FasL and TRAIL play a minor role. In contrast, iTreg cell-induced cytotoxicity of NK cells is mediated by perforin and FasL-associated pathways. In the next series of experiments, we wanted to further characterize the phenotype of NK cells after co-culture with iTreg cells to potentially explain increased NK cell activity.

Some of the most frequently studied HDPs are the cathelicidins, i

Some of the most frequently studied HDPs are the cathelicidins, including human LL-37 and its rodent ortholog mouse cathelin-related antimicrobial peptide (mCRAMP). Cathelicidins are characterized by a conserved cathelin pro-domain located near the N-terminus that is removed as the peptide is secreted, leaving the active HDP 1, 5. It is well known that cathelicidins and other HDPs influence adaptive immunity by acting on APCs (Fig. 1). Cathelicidins are secreted and taken up by macrophages, B cells, and DCs and their effects on these cells lead to selective

immune activation 1, 2, 6. Immature monocyte-derived DCs (MDDCs) transport LL-37 into the cytoplasm and nucleus, Pim inhibitor where LL-37 acts to upregulate CD86 and HLA-DR expression 7. MDDCs derived in the presence of LL-37 also show various changes in surface expression including increased CD86 and CD11b in immature MDDCs 8. These markers are associated with activation of the adaptive response; however, in response to Toll-like receptor (TLR) ligands, including lipopolysaccharide (LPS), cathelicidins can limit DC activation. For example, a model of allergic contact dermatitis found that wild-type mice had significantly decreased DC maturation and inflammation

in response to LPS sensitization as compared with mice lacking mCRAMP 9. Kandler et al. 10 found that LPS and other TLR ligands selleck screening library in combination with LL-37 led to a decrease in expression of HLA-DR, CD86, and other markers when applied to DCs. Loperamide When such DCs were co-cultured with CD4+ T cells, this reduced T-cell proliferation and their production of the T-cell activators IL-2 and IFN-γ 10. Conversely, MDDCs derived with LL-37 in the culture medium showed normal maturation and increased CD11b

and CD86 expression in response to LPS, and co-cultured T cells exposed to LPS and LL-37 had increased IFN-γ production but no significant change in cell proliferation 8, consistent with the concept that HDPs modulate rather than suppress or stimulate immune responses. Other APCs include the M1 and M2 macrophages, polarized to a pro- and anti-inflammatory response, respectively. M1 macrophages promote the maturation of naïve CD4+ T cells into Th1 cells, leading to activation of cell-mediated immunity, whereas M2 macrophages promote the development of Th2 cells and the humoral response. Both M1 and M2 macrophages show decreased TNF-α production in response to LL-37 11, but LL-37 has also been demonstrated to make M2 macrophages more pro-inflammatory 12. Together, these studies show that immune responses to cathelicidins depend on when the cathelicidin is applied and the presence of other signaling molecules such as TLR ligands. While cathelicidins clearly influence APCs and their interactions with adaptive immune cells, evidence is emerging that cathelicidins have a more direct influence on the adaptive response.

The analyser was run and maintained according to the manufacturer

The analyser was run and maintained according to the manufacturer’s instructions. RF was measured by nephelometry on the BNII analyser reading at a wavelength of 840 nm. The analyser was serviced and operated as directed by the manufacturer.

All assay results were validated using third-party internal controls in conjunction with the Biorad QC Oncall package. Appropriate Westgard rules were determined by Westgards’ QC Validator software package version 2·0 (Westgard QC, Madison, WI, USA) to monitor assay performance. Human anti-mouse antibodies (HAMA) were measured using the Alpha Diagnostic International (ADI) enzyme-linked immunosorbent assay (ELISA) kit (Autogen Bioclear, Calne, UK). HAMA in the patients’ serum is detected by a sandwich ELISA Selleck PF-2341066 technique using immobilized mouse IgG and horseradish peroxidase-conjugated anti-human IgG. The concentrations of HAMA were determined against standards

supplied with the kit. Patient samples with a mean absorbance of 0·088 at 450 nm are negative, and patients treated with mouse monoclonal antibodies have a mean absorbance of around 0·559. The manufacturers claim intra-assay coefficient of variations of between 4·2 and 8·3% (mean 6·0%), suggesting Napabucasin research buy that the maximum upper limit of negativity has an A450 of 0·095. A positive serum control from the manufacturer was run with each batch of patient samples. The manufacturers state that RF does not interfere with the measurement of HAMA, although clearly any RF may bind potentially to mouse IgG Fc and therefore behave as a form of HAMA. Heterophilic antibody blocking tubes (HBT) tubes (Scantibodies® Endonuclease Laboratories

Inc., Laboratoire Scantibodies, Villebon/Yvette, France) have been reported to block heterophile antibodies (HAMA and RF) in serum [8]. Five hundred µl of serum is added to the HBT tube, mixed gently by inversion and incubated for 1 h, before re-analysis. The Scantibodies HBT (http://www.scantibodies.com/scanhbr.html) contains a blocking reagent composed of specific binders which inactivate heterophilic interference from HAMA, human anti-goat antibodies, human anti-sheep antibodies, human anti-rabbit antibodies and RF by stearic hinderance effect. Each of the 83 samples was separated into two aliquots. One aliquot was treated with HBT blocking tubes to remove heterophile antibodies. Both treated and untreated aliquots were assayed for MCT and RF on a single run. Five samples containing tryptase with values of less than 1·0 µg/l and RF with values of less than 9·8 IU/ml were assayed in the same way to act as negative controls. The presence of HAMA was determined on pre- and post-blocked sera and used to validate the blocking performance of the HBT tubes. Throughout the study we have used the clinically accepted cut-off for MCT in the UK of 14 µg/l as the ‘upper limit’ of normal, and have designated a RF of less than 14 IU/ml as negative.

In marked contrast, lactic acid had no effect on

In marked contrast, lactic acid had no effect on PD0325901 clinical trial lipopolysaccharide-induced TNF-α, IL-6, IL-10 or IL-12 cytokine release by PBMCs. These results are summarized in Table 1. Evaluating the individual results from each of the 10 subjects revealed that inclusion of lactic acid resulted in a mean 246% increase in IL-23 release over that of lipopolysaccharide

alone. In contrast, IL-23 production in the presence of neutralized lactic acid was a mean of 98% of that observed with lipopolysaccharide alone (Fig. 1). In the absence of lipopolysaccharide, lactic acid did not stimulate the production of IL-23 or any of the other cytokines above background levels. Similarly, the substitution of HCl for lactic acid did not result in the stimulation of cytokine release (data not shown). Preincubation Romidepsin cost in lactic acid had no observable effect on cell viability. The gender of the PBMC donor did not influence the results. The effect of lactic acid concentration on lipopolysaccharide-induced

IL-23 production is shown in Fig. 2. IL-23 levels increased in direct proportion to the lactic acid concentration from 15 to 60 mM and then markedly decreased at 120 mM lactic acid. The pH of the culture medium (8.0 in the absence of lactic acid) decreased to 7.5, 7.2, 7.0, 6.8 and 6.4 with the addition of 15, 30, 45, 60 and 120 mM lactic acid, respectively. Lactic acid, in a dose-dependent manner, selectively promoted the release of IL-23 by PBMCs in response to lipopolysaccharide. IL-23 maintains T helper cell development along the Th17 pathway. Th17 cells release IL-17, which induces the mobilization, recruitment and activation of neutrophils to mucosal surfaces (Kolls & Linden, 2004). In addition, proinflammatory cytokines and chemokines are induced from epithelial cells, endothelial cells and macrophages (Weaver et al., 2007). Thus, at body

sites characterized by the production and release of lactic acid, contact of gram-negative bacteria with antigen-presenting cells would result in the selective activation of the Th17 T lymphocyte pathway and enhanced protection against extracellular pathogens. Lactic acid, at a concentration as low as 5 mM, has also been reported to inhibit Immune system the release of TNF-α by lipopolysaccharide-stimulated human monocytes without affecting viability (Dietl et al., 2010). However, in the present study, lactic acid did not influence TNF-α production by PBMCs. Possibly, the additional presence of lymphocytes attenuated this inhibitory activity. The uptake of the lactate anion into cells is facilitated by a low extracellular pH, due to the formation of a pH gradient between the extracellular and the internal cellular milieu (Loike et al., 1993). Thus, the acidic environment of the human lower genital tract would be a preferred site for this activity.

For these reasons, useful

For these reasons, useful Roxadustat in vivo classification tree models and diagnostic models have been promptly built up by this technique in several medical realms such as cancer, autoimmune disease, haematological disease and mental diseases [16–19]. In our study, we used the data of a training set to construct a classification tree model that help accurately discriminate patients with active TB from patients with other respiratory diseases and healthy people, and then we applied this model to a test set to verify its performance of classification. Patients.  According to the case definitions described elsewhere, 75 patients

with active TB (active TB group) and 103 individuals (non-TB group) including 43 patients with common respiratory diseases (CRD subgroup) and 60 healthy controls (HC subgroup) were recruited from 309th hospital of Chinese PLA. These patients were randomly divided into two sets: a training set and a test set. Our study was approved by the ethics committee of Peking Union Medical College Hospital, and informed consent was obtained from each patient and volunteer. Case definitions.  Diagnosis JQ1 clinical trial of active TB was based on several criteria as follows: (1) sputum smear positive of

acid-fast bacilli or culture positive of M.tb, (2) positive TST, (3) specific symptoms such as persistent cough, weight loss, and night sweats and (4) characteristic changes of chest X-ray (CXR) like lung with cavities in upper lobes. Sputum smear-positive TB (SPP-TB) and smear-negative TB (SNP-TB) patients were classified according to widely accepted criteria [20], and all patients with SNP-TB were ultimately confirmed if their symptoms and CXR turned better after 3 months of anti-TB treatment. TST was performed on active TB group in their first visit according to standard intradermal

Mantoux test with 5 IU purified protein derivative of Bacillus Calmette-Guerin (BCG) (Chengdu institute of biological product, Sichuan, China) and read after 72 h. An induration of ≥5 mm is considered a positive test [21]. Anyone who met the criteria above or had a history of contact with active TB patients was excluded from the non-TB Resminostat group. To rule out latent patients with TB from this group, individuals that have received BCG vaccination before should be negative in IGRA (QuantiFERON®-TB Gold in Tube; Cellestis, Carnegie, Vic., Australia), which was performed according to the manufacturer’s instructions (cut-off value ≥ 0.35 IU/ml), and other individuals in the non-TB group should be negative of TST. In CRD subgroup, patients with lung cancer and sarcoidosis were diagnosed according to their biopsy evaluation, while patients with pneumonia, COPD, and bronchiectasia were diagnosed based on their clinical manifestations, radiographic features and prompt clinical response to regular therapy.

5 It is involved in regulating a range of functions including pha

5 It is involved in regulating a range of functions including phagocytosis, cell adhesion and migration.6–8 CD47 was also found to be a receptor for the extracellular matrix protein thrombospondin,6 and to function as the ligand for signal regulatory protein α (SIRPα/CD172a).7,9 CD172a

is a cell surface immunoglobulin superfamily member expressed by most myeloid cells, but also by non-haematopoietic cells such as vascular endothelial cells selleck products and smooth muscle cells.10,11 The cytoplasmic tail of CD172a contains immunoreceptor tyrosine-based inhibitory motifs that, upon phosphorylation, are able to recruit the tyrosine phosphatases SHP-1 or SHP-2. These phosphatases in turn modulate phagocytosis, cell migration and cellular responses to growth factors and other soluble signalling molecules.12 Not only interaction between CD47 and CD172a, but also integrin-mediated cell adhesion,10,11 leads to phosphorylation of the CD172a immunoreceptor tyrosine-based inhibitory motifs and regulation of these cellular functions. Blood monocytes, macrophages, granulocytes and MG-132 research buy CD11b+ (CD4+) DC express CD172a.13,14 The expression of both CD47 and CD172a has recently been shown to be required for the homeostasis of CD11b+ DC in lymphoid organs,15 and also to regulate migration of this DC subset from skin to the draining

lymph nodes (LN).13,14,16 In intestinal tissues, CD172a–CD47 interactions are also required for the regulation of eosinophil degranulation and homeostasis.17 CD47 is crucial for cellular recruitment to sites of intestinal inflammation, as mice lacking CD47 (CD47−/−) fail to recruit CD172a+ CD11c+ cells to the gut and are therefore protected from trinitrobenzenesulphonic acid-induced colitis.18 Moreover, CD47 has been demonstrated to negatively regulate inducible Foxp3+ T regulatory cells expressing CD103, resulting in increased proliferation and accumulation of the T regulatory cells with age in CD47−/− mice.19 However, the role of CD47 in both the induction of immune responses following oral immunization with adjuvants and the maintenance of oral tolerance has not been investigated. In this study we use CD47−/− mice to

explore the role of CD47 and gut-associated lymphoid tissue (GALT) -resident CD172a+ antigen-presenting cells in the induction of oral tolerance and Bcl-w following immunization with the adjuvant CT. We observe that CD47−/− mice exhibit reduced total cell numbers selectively in the GALT. In addition, we show that the frequency of CD11b+ CD172a+ DC is reduced by 50% in the small intestine and draining mesenteric lymph nodes (MLN) but not in the Peyer’s patches (PP). Although MLN are required for oral tolerance induction, CD47−/− mice maintain this capacity despite their diminished cell numbers. In contrast, production of antigen-specific intestinal IgA following oral immunization is significantly reduced in CD47−/− mice, although normal antigen-specific systemic IgG and total IgA levels are maintained.