Effects of Friend Virus Infection and Regulatory T Cells on the Antigen Presentation Function of B Cells.

Friend virus (FV) is a naturally occurring mouse retrovirus that infects dividing cells of the hematopoietic lineage, including antigen-presenting cells (APCs). The infection of APCs by viruses often induces their dysfunction, and it has been shown that FV infection reduces the ability of dendritic cells (DCs) to prime critical CD8+ T cell responses. Nonetheless, mice mount vigorous CD8+ T cell responses, so we investigated whether B cells might serve as alternative APCs during FV infection. Direct ex vivo analysis of B cells from FV-infected mice revealed that infected but not uninfected B cells upregulated expression of the costimulatory molecules CD80, CD86, and CD40, as well as major histocompatibility complex class II (MHC-II) molecules. Furthermore, in vitro studies showed that, compared to uninfected B cells from the same mice, the FV-infected B cells had significantly enhanced APC function, as measured by their capacity to prime CD8+ T cell activation and proliferation. Thus, in contrast to DCs, infection of B cells with FV enhanced their APC capacity and ability to stimulate the CD8+ T cell responses essential for virus control. FV infections also induce the activation and expansion of regulatory T cells (Tregs), so it was of interest to determine the impact of Tregs on B cell activation. The upregulation of costimulatory molecule expression and APC function of B cells was even more strongly enhanced by in vivo depletion of regulatory T cells than infection. Thus, Tregs exert potent homeostatic suppression of B cell activation that is partially overcome by FV infection.IMPORTANCE The primary role of B cells in immunity is considered the production of pathogen-specific antibodies, but another, less-well-studied, function of B cells is to present foreign antigens to T cells to stimulate their activation and proliferation. Dendritic cells (DCs) are considered the most important antigen-presenting cells (APCs) for CD8+ T cells, but DCs lose APC function when infected with Friend virus (FV), a model retrovirus of mice. Interestingly, B cells were better able to stimulate CD8+ T cell responses when they were infected with FV. We also found that the activation status of B cells under homeostatic conditions was potently modulated by regulatory T cells. This study illustrates an important link between B cell and T cell responses and illustrates an additional mechanism by which regulatory T cells suppress critical T cell responses during viral infections.

Efficacy of different hemodialysis methods on dendritic cell marker CD40 and CD80 and platelet activation marker CD62P and P10 in patients with chronic renal failure.

BACKGROUND: Chronic renal failure (CRF) has become a major public health concern, which increases the risk of stroke and systemic thromboembolism. Therefore, therapeutic strategies are in urgent requirement. This study was conducted for investigating efficacy of hemodialysis (HD), hemodiafiltration (HDF), and hemoperfusion (HP) in patients with CRF and the correlation with the presence of complications following HD therapy. METHODS: The therapeutic effect, living quality, biochemical indicators, and dry weight were detected before and after the treatment regimens. Flow cytometry was conducted to detect expressions of dendritic cell markers (CD40 and CD80) and platelet activation markers (CD62P and P10), and the relationship between their expression and therapeutic effect as well as the association of these expressions with complications was analyzed. RESULTS: After HD therapy, patients presented with decreased serum creatinine, serum phosphorus, triglyceride, parathyroid hormone, and ß2 -MG expression; increased hemoglobin, plasma albumin expressions, and dry weight; and enhanced therapeutic effect and living quality. CD62P and P10 expressions decreased, while CD40 and CD80 expressions increased following HD therapy. The therapeutic effect improved in patients with low expressions of CD40 and CD80 and high expressions of CD62P and P10 following HP treatment and complications were lower after treatment of HDF and HP. CONCLUSION: The aforementioned results indicated that CRF patients treated with HP exhibited higher expression of CD40 and CD80 and lower expression of CD62P and P10, suggesting that HP is conferred to have better efficacy than HDF and HD. Therefore, HP may be a promising clinical regimen for treatment of CRF patients.

Evaluation of monocyte subsets and markers of activation in leprosy reactions.

Understanding host immune pathways associated with tissue damage during reactions are of upmost importance to the development of immune intervention strategies. The participation of monocytes in leprosy reactions was evaluated by determining the frequency of monocyte subsets and the degree of cellular activation through the expression of MHCII and the co-stimulatory molecules CD40, CD80, CD86. Leprosy subjects with or without reactions were included in this cross-sectional study. Peripheral blood mononuclear cell were isolated and stained ex vivo to determine monocyte subsets and the degree of cellular activation by flow cytometry. Intermediate monocytes were increased in leprosy patients with reactions when compared to patients without reactions. Although no difference was detected in the frequency of monocyte subsets between type 1 and 2 reactions, the expression of CD80 was increased in monocytes from patients with type 1 reactions and CD40 was higher in paucibacillary subjects presenting type 1 reactions. Moreover, CD86 and MHC II expression were higher in intermediate monocytes when compared to the other subsets in leprosy reaction types 1 and 2. Intermediate monocyte activation with CD86 and MHCII expression is involved with both type 1 and 2 reactions, whereas CD80 and CD40 expression is related to type 1 reactions.

Antibody Drug-Target Engagement Measurement in Tissue Using Quantitative Affinity Extraction Liquid Chromatography-Mass Spectrometry: Method Development and Qualification.

We demonstrate a novel strategy using affinity extraction (AE) LC-MS to directly measure drug exposure and target engagement, two critical pharmacological questions, with a single assay. The assay measures total drug and target concentration at the site of therapeutic action, as well as the amount of target bound to drug. The case study presented applies the strategy to measure drug engagement of a membrane bound receptor (CD40) that is critical to immune regulation in colon biopsies collected from monkey dosed with an anti-CD40 antibody. Unlike other techniques that measure receptor occupancy, such as flow cytometry, this technique does not rely on viable cells allowing measurement of frozen samples in a remote setting from the clinic.

Staphylococcal ß-Toxin Modulates Human Aortic Endothelial Cell and Platelet Function through Sphingomyelinase and Biofilm Ligase Activities.

Staphylococcus aureus causes many infections, such as skin and soft tissue, pneumonia, osteomyelitis, and infective endocarditis (IE). IE is an endovascular infection of native and prosthetic valves and the lining of the heart; it is characterized by the formation of cauliflower-like "vegetations" composed of fibrin, platelets, other host factors, bacteria, and bacterial products. ß-Toxin is an S. aureus virulence factor that contributes to the microorganism's ability to cause IE. This cytolysin has two enzymatic activities: sphingomyelinase (SMase) and biofilm ligase. Although both activities have functions in a rabbit model of IE, the mechanism(s) by which ß-toxin directly affects human cells and is involved in the infectious process has not been elucidated. Here, we compared the in vitro effects of purified recombinant wild-type ß-toxin, SMase-deficient ß-toxin (H289N), and biofilm ligase-deficient ß-toxin (H162A and/or D163A) on human aortic endothelial cells (HAECs) and platelets. ß-Toxin was cytotoxic to HAECs and inhibited the production of interleukin 8 (IL-8) from these cells by both SMase and biofilm ligase activities. ß-Toxin altered HAEC surface expression of CD40 and vascular cell adhesion molecule 1 (VCAM-1). HAECs treated with ß-toxin displayed granular membrane morphology not seen in treatment with the SMase-deficient mutant. The altered morphology resulted in two possibly separable activities, cell rounding and redistribution of cell membranes into granules, which were not the result of endosome production from the Golgi apparatus or lysosomes. ß-Toxin directly aggregated rabbit platelets via SMase activity.IMPORTANCE Each year there are up to 100,000 cases of infective endocarditis (IE) in the United States. S. aureus is the most common pathogen in patients with health care-associated IE and the leading cause of community-associated IE in the developed world. Multiple clonal group strains as defined by the Centers for Disease Control and Prevention, particularly USA200 and other clones encoding ß-toxin, are highly associated with IE. Considering the strong association and established contribution of ß-toxin in animal models of IE, determining how ß-toxin directly affects human cell types, including endothelial cells and platelets, is important. In this study, we demonstrate that ß-toxin functions to modulate endothelial cells and platelets by both toxin sphingomyelinase and biofilm ligase activities. Our data suggest that these activities modulate inflammation and increase infection severity.

Interaction between tumour-infiltrating B cells and T cells controls the progression of hepatocellular carcinoma.

OBJECTIVE: The nature of the tumour-infiltrating leucocytes (TILs) is known to impact clinical outcome in carcinomas, including hepatocellular carcinoma (HCC). However, the role of tumour-infiltrating B cells (TIBs) remains controversial. Here, we investigate the impact of TIBs and their interaction with T cells on HCC patient prognosis. DESIGN: Tissue samples were obtained from 112 patients with HCC from Singapore, Hong Kong and Zurich and analysed using immunohistochemistry and immunofluorescence. RNA expression of CD19, CD8A, IFNG was analysed using quantitative PCR. The phenotype of freshly isolated TILs was analysed using flow cytometry. A mouse model depleted of mature B cells was used for functional study. RESULTS: Tumour-infiltrating T cells and B cells were observed in close contact with each other and their densities are correlated with superior survival in patients with HCC. Furthermore, the density of TIBs was correlated with an enhanced expression of granzyme B and IFN-γ, as well as with reduced tumour viability defined by low expression of Ki-67, and an enhanced expression of activated caspase-3 on tumour cells. CD27 and CD40 costimulatory molecules and TILs expressing activation marker CD38 in the tumour were also correlated with patient survival. Mice depleted of mature B cells and transplanted with murine hepatoma cells showed reduced tumour control and decreased local T cell activation, further indicating the important role of B cells. CONCLUSIONS: The close proximity of tumour-infiltrating T cells and B cells indicates a functional interaction between them that is linked to an enhanced local immune activation and contributes to better prognosis for patients with HCC.

Tumor Necrosis Factor Receptor Associated Factors (TRAFs) 2 and 3 Form a Transcriptional Complex with Phosho-RNA Polymerase II and p65 in CD40 Ligand Activated Neuro2a Cells.

The tumor necrosis factor receptor-associated factors (TRAFs) have been classically described as adaptor proteins that function as solely cytosolic signaling intermediates for the TNF receptor superfamily, Toll-like receptors (TLRs), NOD, like receptors (NLRs), cytokine receptors, and others. In this study, we show for the first time that TRAFs are present within the cytoplasm and nucleus of Neuro2a cells and primary cortical neurons, and that TRAF2 and TRAF3 translocate into the nucleus within minutes of CD40L stimulation. Analysis of the transcriptional regulatory potential of TRAFs by luciferase assay revealed that each of the TRAFs differentially functions as a transcriptional activator or repressor in a cell-specific manner. Interestingly, ChIP-qPCR data demonstrate that TRAFs 2/3, p65, and pRNAPol II form part of a transcriptional complex on the Icam-1 gene promoter upon CD40L stimulation. We further determined that TRAF2 recruitment to the nucleus is critical for the ubiquitination of H2b, a transcription permissive epigenetic modification. Our findings demonstrate for the first time that TRAFs 2/3 participate in the formation of a CD40L-induced transcriptional complex in neuronal cells.

B cells from African American lupus patients exhibit an activated phenotype.

Systemic lupus erythematosus (SLE) is a complex systemic autoimmune disease driven by both innate and adaptive immune cells. African Americans tend to present with more severe disease at an earlier age compared with patients of European ancestry. In order to better understand the immunological differences between African American and European American patients, we analyzed the frequencies of B cell subsets and the expression of B cell activation markers from a total of 68 SLE patients and 69 normal healthy volunteers. We found that B cells expressing the activation markers CD86, CD80, PD1, and CD40L, as well as CD19+CD27-IgD- double-negative B cells, were enriched in African American patients vs. patients of European ancestry. In addition to increased expression of CD40L, surface levels of CD40 on B cells were lower, suggesting the engagement of the CD40 pathway. In vitro experiments confirmed that CD40L expressed by B cells could lead to CD40 activation and internalization on adjacent B cells. To conclude, these results indicate that, compared with European American patients, African American SLE patients present with a particularly active B cell component, possibly via the activation of the CD40/CD40L pathway. These data may help guide the development of novel therapies.

Density and Polarization States of Tumor-Associated Macrophages in Human Cutaneous Squamous Cell Carcinomas Arising in Solid Organ Transplant Recipients.

BACKGROUND: Solid organ transplant recipients (SOTRs) are 100 times more likely to develop cutaneous squamous cell carcinoma (SCC) with greater metastatic propensity compared with the general population, likely due to chronic immunosuppression and adverse drug effects on keratinocytes. Tumor-associated macrophages (TAMs) play critical roles in malignancies, either aiding in eradication of malignant cells or promoting tumor growth. OBJECTIVE: The authors examined whether TAM density and polarization states differ between SOTRs and nontransplant individuals. MATERIALS AND METHODS: The authors obtained normal skin, SCC in situ (SCCis), and SCC from SOTRs and nontransplant patients (N = 45) and stained with macrophage marker CD68, M1 marker CD40, and M2 marker arginase-1. RESULTS: The authors report a significantly higher density of TAMs in both SCCis and SCC. The intratumoral macrophage infiltration in SCCis from SOTR was significantly decreased compared with nontransplant patients. Tumor-associated macrophages in SCCis and SCC displayed both M1 and M2 polarization, and M2 activation levels were significantly lower in SCC from SOTR. CONCLUSION: Tumor-associated macrophages are present in early carcinogenesis and may play a critical role in the transition from SCCis to SCC, before invasion of the basement membrane by tumor cells. The intratumoral macrophage density in early stages of tumor development is significantly affected in SOTR.

Impact of cardiac surgery on the expression of CD40, CD80, CD86 and HLA-DR on B cells and monocytes.

OBJECTIVE: We measured and compared changes in the percentage of cells expressing CD80, CD86, CD40, HLA-DR and the expression of these molecules on B cells and monocytes of patients who underwent either on-pump, mini on-pump or off-pump cardiac surgery. METHODS: Blood samples from patients who underwent either on-pump, mini on-pump or off-pump cardiac surgery were collected before surgery, instantly after surgery and on the 1(st), 3(rd) and 7(th) days after surgery. Surface expression of CD80, CD86, CD40 and HLA-DR molecules was determined by flow cytometry. RESULTS: Our results show that all three surgical techniques altered the expression of these molecules, as well as the percentage relative number of specific cell populations. We identified statistically significant differences when comparing different surgical techniques. On-pump surgery revealed a more pronounced impact on the phenotype of immune system cells than the other techniques. Therefore, it is likely that the function of immune cells is changed the most by on-pump surgery. We found a lower decrease in the number of CD80(+) monocytes and a lower drop in the CD40 expression on monocytes in off-pump patients in comparison with on-pump patients. CONCLUSION: All the types of cardiac surgical techniques, off-pump, on-pump and modified mini-invasive on-pump, are associated with changes in CD80, CD86, CD40 and HLA-DR expression. We found several significant differences in the expression of the selected molecules when we compared all three groups of patients.

[Effect of ICOS signaling on CD154/CD40 expressions in mice infected with Schistosoma japonicum].

OBJECTIVE: To explore the effect of ICOS signaling on the CD154/CD40 expressions and immunopathology in mice infected with Schistosoma japonicum. METHODS: ICOS transgenic (ICOS-Tg) mice and wildtype FVB/NJ mice were used as experimental schistosomiasis models. The expressions of CD154 and CD40 on splenocytes and on inflammatory cells around granulomatous infiltration of the liver in the mice infected with S. japonicuin were detected by flow cytometry and im- munohistochemical staining. HE staining was applied to observe the changes on the granulomatous of the mice liver. RESULTS: Compared with the wildtype FVB/NJ mice, the expressions of CD154 on CD4 T splenocytes and of CD40 on CD19' B splenocytes in the ICOS-Tg mice significantly increased in 12 and 16 weeks post-infection (all P < 0.05). Moreover, the expressions of CD40 and CD154 on inflammatory cells around granulomatous infiltration in the liver of the ICOS-Tg mice were significantly higher than those of the wildtype FVB/NJ mice in 7, 12, 16 and 20 weeks post-infection (all P < 0.05). The volumes of liver egg granulomas of the ICOS-Tg mice were significantly bigger than those of the wildtype mice (P < 0.05 or P < 0.01). CONCLUSIONS: In ICOS-Tg mice infected with S. japonicum, the ICOS signaling has a regulatory effect on CD154/CD40 expressions, and may play an important role in the hepatic egg granuloma formation of schistosomiasis.

Saliva suppresses osteoclastogenesis in murine bone marrow cultures.

Saliva can reach mineralized surfaces in the oral cavity; however, the relationship between saliva and bone resorption is unclear. Herein, we examined whether saliva affects the process of osteoclastogenesis in vitro. We used murine bone marrow cultures to study osteoclast formation. The addition of fresh sterile saliva eliminated the formation of multinucleated cells that stained positive for tartrate-resistant acid phosphatase (TRAP). In line with the histochemical staining, saliva substantially reduced gene expression of cathepsin K, calcitonin receptor, and TRAP. Addition of saliva led to considerably decreased gene expression of receptor activator of nuclear factor kappa-B (RANK) and, to a lesser extent, that of c-fms. The respective master regulators of osteoclastogenesis (c-fos and NFATc1) and the downstream cell fusion genes (DC-STAMP and Atp6v0d2) showed decreased expression after the addition of saliva. Among the costimulatory molecules for osteoclastogenesis, only OSCAR showed decreased expression. In contrast, CD40, CD80, and CD86-all costimulatory molecules of phagocytic cells-were increasingly expressed with saliva. The phagocytic capacity of the cells was confirmed by latex bead ingestion. Based on these in vitro results, it can be concluded that saliva suppresses osteoclastogenesis and leads to the development of a phagocytic cell phenotype.

Differential partial activation phenotype and production of tumour necrosis factor-α by conventional dendritic cells in response to lipopolysaccharide in HIV+ viraemic subjects and HIV+ controllers.

HIV(+) subjects are reported to have increased soluble CD14 (sCD14) in plasma, an indicator of microbial translocation. We evaluated if microbial translocation has a differential impact on the activation and function of conventional dendritic cells (cDC) from viraemic HIV(+) subjects and HIV(+) controllers (CTs). The HIV(+) subjects were classified into two groups according to their plasma viral load (pVL): CT and viraemic. Subjects without HIV were included as controls (HIV(-) ). The frequencies and phenotypes of cDC from these subjects were evaluated by multi-parameter flow cytometry. In addition, peripheral blood mononuclear cells (PBMCs) were stimulated with lipopolysaccharide (LPS) or single-stranded RNA40 (ssRNA40), the phenotype of the cDC and the intracellular production of tumour necrosis factor (TNF)-α by the cDC were evaluated by flow cytometry. We observed a partial activation phenotype for the cDC in the viraemic subjects and CTs ex vivo and after LPS activation, which showed differences in the expression of CD40 and CD86. Furthermore, in response to LPS the cDC from the viraemic subjects produced more TNF-α compared to the cDC from CTs. Interestingly, the percentage of TNF-α(+) cDC was found to be correlated positively with the pVL. The partial activation of cDC and the over-production of TNF-α in response to LPS in viraemic HIV(+) subjects might be related to the increased chronic activation observed in these subjects. In contrast, cDC from CTs seem to have a regulated response to LPS, indicating that they respond differently to chronic immune activation. These results may have implications in the development of HIV therapies and vaccines using DC.

Porphyromonas gingivalis lipopolysaccharide weakly activates M1 and M2 polarized mouse macrophages but induces inflammatory cytokines.

Porphyromonas gingivalis is associated with chronic periodontitis, an inflammatory disease of the tooth's supporting tissues. Macrophages are important in chronic inflammatory conditions, infiltrating tissue and becoming polarized to an M1 or M2 phenotype. As responses to stimuli differ between these phenotypes, we investigated the effect of P. gingivalis lipopolysaccharide (LPS) on M1 and M2 macrophages. M1 and M2 polarized macrophages were produced from murine bone marrow macrophages (BMMϕ) primed with gamma interferon (IFN-γ) or interleukin-4 (IL-4), respectively, and incubated with a low or high dose of P. gingivalis LPS or control TLR2 and TLR4 ligands. In M1-Mϕ, the high dose of P. gingivalis LPS (10 µg/ml) significantly increased the expression of CD40, CD86, inducible nitric oxide synthase, and nitric oxide secretion. The low dose of P. gingivalis LPS (10 ng/ml) did not induce costimulatory or antibacterial molecules but did increase the secretion of IL-1α, IL-6, IL-12p40, IL-12p70, and tumor necrosis factor alpha (TNF-α). P. gingivalis LPS marginally increased the expression of CD206 and YM-1, but it did enhance arginase expression by M2-Mϕ. Furthermore, the secretion of the chemokines KC, RANTES, eotaxin, and MCP-1 from M1, M2, and nonpolarized Mϕ was enhanced by P. gingivalis LPS. TLR2/4 knockout macrophages combined with the TLR activation assays indicated that TLR2 is the main activating receptor for P. gingivalis LPS and whole cells. In conclusion, although P. gingivalis LPS weakly activated M1-Mϕ or M2-Mϕ compared to control TLR ligands, it induced the secretion of inflammatory cytokines, particularly TNF-α from M1-Mϕ and IL-10 from M2-Mϕ, as well as chemotactic chemokines from polarized macrophages.

Unconventional maturation of dendritic cells induced by particles from the laminated layer of larval Echinococcus granulosus.

The larval stage of the cestode parasite Echinococcus granulosus causes hydatid disease in humans and livestock. This infection is characterized by the growth in internal organ parenchymae of fluid-filled structures (hydatids) that elicit surprisingly little inflammation in spite of their massive size and persistence. Hydatids are protected by a millimeter-thick layer of mucin-based extracellular matrix, termed the laminated layer (LL), which is thought to be a major factor determining the host response to the infection. Host cells can interact both with the LL surface and with materials that are shed from it to allow parasite growth. In this work, we analyzed the response of dendritic cells (DCs) to microscopic pieces of the native mucin-based gel of the LL (pLL). In vitro, this material induced an unusual activation state characterized by upregulation of CD86 without concomitant upregulation of CD40 or secretion of cytokines (interleukin 12 [IL-12], IL-10, tumor necrosis factor alpha [TNF-α], and IL-6). When added to Toll-like receptor (TLR) agonists, pLL-potentiated CD86 upregulation and IL-10 secretion while inhibiting CD40 upregulation and IL-12 secretion. In vivo, pLL also caused upregulation of CD86 and inhibited CD40 upregulation in DCs. Contrary to expectations, oxidation of the mucin glycans in pLL with periodate did not abrogate the effects on cells. Reduction of disulfide bonds, which are known to be important for LL structure, strongly diminished the impact of pLL on DCs without altering the particulate nature of the material. In summary, DCs respond to the LL mucin meshwork with a "semimature" activation phenotype, both in vitro and in vivo.

Removal of biological response modifiers associated with platelet transfusion reactions by columns containing adsorption beads.

BACKGROUND: Biological response modifiers (BRMs), such as soluble CD40 ligand (sCD40L); regulated upon activation, normal T-cell expressed, and secreted (RANTES); and transforming growth factor-ß1 (TGF-ß1), are released from platelets (PLTs) during storage and may trigger adverse effects after PLT transfusion. Although washing PLTs is effective at reducing the level of BRMs and the incidence of transfusion reactions, the washing procedure is time-consuming and may induce PLT activation. Furthermore, some BRMs continue to accumulate during the storage of washed PLTs. A method to remove BRMs using adsorbent columns has not yet been developed. STUDY DESIGN AND METHODS: We evaluated the ability of columns packed with Selesorb and Liposorber beads, which are both clinically used, to remove BRMs from PLT concentrates (PCs) stored for 5 days. The levels of these BRMs were determined before and after adsorption. RESULTS: The adsorption columns significantly reduced the levels of RANTES and sCD40L and partially reduced TGF-ß1. There were no significant effects on PLT activation, aggregation, morphology, and plasma lactate dehydrogenase (an indicator of PLT lysis) levels, or hypotonic shock response. Adsorption, however, reduced the PLT recovery to approximately 60% of the untreated value. CONCLUSIONS: This study showed that the levels of BRMs were substantially reduced using columns of clinically available adsorption beads. PLT functions and the quality of PCs were maintained after adsorption. The use of adsorption columns may be useful in reducing the incidence of nonhemolytic transfusion reactions.

Neuroprotective effect of AG490 in experimental traumatic brain injury of rats.

BACKGROUND: Traumatic brain injury (TBI) is a major cause of death and disability in children and young adults worldwide. Therefore, we investigated the role of AG490 in regulating brain oedema, expression of CD40 and neurological function after TBI. METHODS: Sprague Dawley rats (n = 240) were randomly divided into a sham operation group, TBI+saline group and TBI+AG490 (JAK/STAT inhibitor) group. Members of each group were euthanized at 6, 12, 24 or 72 hours after injury. Neurological severity score (NSS) was used to evaluate the severity of neurological damage. Brain water was quantitated by wet/dry weight method. The expression of CD40 was assessed by flow cytometry. RESULTS: In both the TBI+saline group and the TBI+AG490 group, the brain water content was elevated after TBI, reached a peak at 24-hour and remained high for the rest of the period investigated; the expression of CD40 reached a peak 24 hours after TBI; the NSS was elevated after TBI and then decreased after 6 hours. Elevations in the level of CD40, degree of brain edema and NSS after TBI were significantly reduced in TBI+AG490 group. CONCLUSION: Inhibition of the JAK/STAT signalling pathway reduces brain oedema, decreases the expression of CD40 and exerts neuroprotective effects after TBI.

CD40 signal regulates CXCR4 mediating ovarian carcinoma cell migration: implications for extrapelvic metastastic factors.

Ovarian carcinomas are highly invasive, especially in the peritoneal cavity. SDF-1α and its receptor, CXCR4, play a crucial role in migration of cancer cells. Here, SDF-1α directed HO8910 cell migration, but not SKOV3 cells. After being educated to express CXCR4 in vivo or by treating with sCD40L, SDF-1α reexhibited the ability of directing SKOV3 cell migration, which could be antagonized by CXCR4-neutralizing antibody. Furthermore, concomitant expression of CXCR4/CD40 in ovarian carcinoma tissues had stronger correlation with pelvic metastasis than did each alone. It is suggest that SDF-1α acts through CXCR4 to induce ovarian cancer cell migration, which could be facilitated by CD40 activation. Simultaneously examining the expression of CXCR4 and CD40 will provide valuable diagnosis of pelvic metastasis for ovarian carcinomas.

Clinical disease upregulates expression of CD40 and CD40 ligand on peripheral blood mononuclear cells from cattle naturally infected with Mycobacterium avium subsp. paratuberculosis.

CD40 and CD40 ligand (CD40L) have costimulatory effects as part of a complex series of events in host immunity. In this study, the expression of CD40 and CD40L on peripheral blood mononuclear cells (PBMCs) isolated from cattle with Johne's disease were measured on freshly isolated PBMCs and on cells cultured for 8, 24, and 72 h in the presence or absence of live Mycobacterium avium subsp. paratuberculosis and exogenous gamma interferon, interleukin 10, and transforming growth factor ß. Results demonstrated greater CD40 and CD40L expression on fresh PBMCs obtained from animals in the clinical stage of disease (symptomatic) than those from healthy control animals or cows in the subclinical stage of disease (asymptomatic). A similar expression profile with greater magnitude was noted for cultured PBMCs, with increased CD40 expression after 8 and 24 h of culture and increased CD40L expression between 24 and 72 h on PBMCs obtained from clinically infected animals. The addition of live M. avium subsp. paratuberculosis to cell cultures resulted in downregulation of CD40L expression in naturally infected cows, regardless of the disease stage. In contrast, the addition of live M. avium subsp. paratuberculosis to cultures resulted in upregulation of CD40 expression on cells obtained from clinically infected animals, while a decrease in expression was noted for healthy and subclinically infected cows. No effects of exogenous cytokines on CD40 or CD40L expression were observed. These results clearly point for the first time to a disparity in the expression of these costimulatory molecules on immune cells from cattle in different stages of Johne's disease and suggest further investigation into their roles in paratuberculosis pathogenesis.

Pathogenic CCR6+ dendritic cells in the skin lesions of discoid lupus patients: a role for damage-associated molecular patterns.

BACKGROUND: Discoid lupus erythematosus (DLE) is a cutaneous autoimmune inflammatory disease in which the role of conventional dendritic cells (cDCs) in skin damage has not been evaluated. OBJECTIVE: To evaluate the involvement of cDCs in DLE pathogenesis. MATERIAL & METHODS: Skin biopsies from 42 patients with DLE were embedded in paraffin or placed in culture. The dermis was separated and cell suspensions were characterized by flow cytometry. RESULTS: We found an increase in cDCs with inflammatory characteristics in the skin of DLE patients, compared with control skins. Interestingly, cDCs from the DLE patients expressed low levels of the inhibitory molecule PD-L1 and showed a high expression of CCR6, which correlated with disease activity. Increased cellular death was observed in the skin of DLE patients compared with control skin and remarkably we found that damage-associated molecular patterns could be responsible for CCR6 expression on cDCs in the skin. CONCLUSIONS: Our results indicate the presence of pathogenic CCR6+ cDCs in the skin lesions of DLE patients, which could result from in situ phenotypic changes.