ortho-Substituted Aryldiazonium Design for the Defect Configuration-Controlled Photoluminescent Functionalization of Chiral Single-Walled Carbon Nanotubes.

Defect functionalization of single-walled carbon nanotubes (SWCNTs) by chemical modification is a promising strategy for near-infrared photoluminescence (NIR PL) generation at >1000 nm, which has advanced telecom and bio/medical applications. The covalent attachment of molecular reagents generates sp3-carbon defects in the sp2-carbon lattice of SWCNTs with bright red-shifted PL generation. Although the positional difference between proximal sp3-carbon defects, labeled as the defect binding configuration, can dominate NIR PL properties, the defect arrangement chemistry remains unexplored. Here, aryldiazonium reagents with π-conjugated ortho-substituents (phenyl and acetylene groups) were developed to introduce molecular interactions with nanotube sidewalls into the defect-formation chemical reaction. The functionalized chiral SWCNTs selectively emitted single defect PL in the wavelength range of ∼1230-1270 nm for (6,5) tubes, indicating the formation of an atypical binding configuration, different from those exhibited by typical aryl- or alkyl-functionalized chiral tubes emitting ∼1150 nm PL. Moreover, the acetylene-based substituent design enabled PL brightening and a subsequent molecular modification of the doped sites using click chemistry.

Enhancing near-infrared photoluminescence from single-walled carbon nanotubes by defect-engineering using benzoyl peroxide.

Single-walled carbon nanotubes (SWCNTs) have been modified with ester groups using typical organic radical chemistry. Consequently, traps for mobile excitons have been created, which enhanced the optical properties of the material. The proposed methodology combines the benefits of mainstream approaches to create luminescent defects in SWCNTs while it simultaneously avoids their limitations. A step change was achieved when the aqueous medium was abandoned. The selection of an appropriate organic solvent enabled much more facile modification of SWCNTs. The presented technique is quick and versatile as it can engage numerous reactants to tune the light emission capabilities of SWCNTs. Importantly, it can also utilize SWCNTs sorted by chirality using conjugated polymers to enhance their light emission capabilities. Such differentiation is conducted in organic solvents, so monochiral SWCNT can be directly functionalized using the demonstrated concept in the same medium without the need to redisperse the material in water.

Acidic environment augments FcεRI-mediated production of IL-6 and IL-13 in mast cells.

Although blood pH is maintained in a narrow range of around pH 7.4 in living organisms, inflammatory loci are characterized by acidic conditions. Mast cells tend to reside close to the surface of the body in areas such as the mucosa and skin where they may be exposed to exogenous acids, and they play an important role in immune responses. However, little is known about the effects of extracellular acidification on the functions of mast cell. Here, we found that extracellular acidification increased the dinitrophenyl-conjugated human serum albumin (DNP-HSA)-induced production of interleukin (IL)-6 and IL-13 in MC/9 cells or bone marrow-derived mouse mast cells sensitized with anti-DNP IgE. Extracellular acidification also inhibited migration of MC/9 cells toward DNP-HSA. In addition, acidic pH stimulated antigen-induced activation of p38 mitogen-activated protein kinase (MAPK) and protein kinase B (Akt). These findings suggest that extracellular acidification augmented antigen/IgE-induced and FcεRI-mediated production of IL-6 and IL-13 in mast cells, and that this was associated with the enhancement of p38 MAPK and Akt activation.

Systemic Cyclosporine Therapy for Scleritis: A Proposal of a Novel System to Assess the Activity of Scleritis.

In the present study, two female patients with unilateral scleritis without systemic complications were examined. Both patients were suffering from ocular pain and received corticosteroid therapy. The first patient, a 45-year-old woman, was diagnosed with scleritis and iritis in her right eye. Topical corticosteroid treatment could eradicate the iritis but not the scleritis. Oral corticosteroid administration and corticosteroid pulse therapy were applied with little effect. The application of systemic cyclosporine had a satisfactory effect in controlling the scleritis. The other patient, a 60-year-old woman, was suffering from scleritis and lid swelling in her right eye. Not only did topical and systemic corticosteroid therapy prove insufficient, they also resulted in the elevation of her intraocular pressure. After termination of corticosteroid therapy, the systemic cyclosporine was applied orally. Subsequently, the patient's scleritis improved without any severe side effects. Scleritis is a painful and destructive inflammatory disease of the sclera that causes congestion of the scleral venous plexus. In this study, we have established a new grading system for assessing activity in scleritis that can score the extent of ocular pain and the area of congestion. This system provides a practical method for following the clinical course and monitoring the outcome of therapy. We report two cases of unilateral scleritis that were resistant to corticosteroid therapy but responsive to systemic administration of cyclosporine. Findings from these cases indicate that cyclosporine is an effective drug for controlling severe scleritis.

Development of a sensitive screening method for selecting monoclonal antibodies to be internalized by cells.

Antibody-drug conjugates (ADCs), drugs developed by conjugation of an anticancer agent to a monoclonal antibody (mAb), have lately attracted attention in cancer therapy because ADCs can directly bind cancer cells and kill them. Although mAbs for ADCs must be internalized by the target cells, few methods are available for screening mAbs for their ability to be internalized by cells. We have developed a recombinant protein, termed DT3C, which consists of diphtheria toxin (DT) lacking the receptor-binding domain but containing the C1, C2, and C3 domains of Streptococcus protein G (3C). When a mAb-DT3C conjugate, which functions in vitro like an ADC, reduces the viability of cancer cells, the mAb being tested must have been internalized by the target cells. DT3C can thus be a tool to identify efficiently and easily mAbs that can be internalized by cells, thereby enhancing the development of promising ADCs.

Ionotropic and metabotropic proton-sensing receptors involved in airway inflammation in allergic asthma.

An acidic microenvironment has been shown to evoke a variety of airway responses, including cough, bronchoconstriction, airway hyperresponsiveness (AHR), infiltration of inflammatory cells in the lung, and stimulation of mucus hyperproduction. Except for the participation of transient receptor potential vanilloid-1 (TRPV1) and acid-sensing ion channels (ASICs) in severe acidic pH (of less than 6.0)-induced cough and bronchoconstriction through sensory neurons, the molecular mechanisms underlying extracellular acidic pH-induced actions in the airways have not been fully understood. Recent studies have revealed that ovarian cancer G protein-coupled receptor 1 (OGR1)-family G protein-coupled receptors, which sense pH of more than 6.0, are expressed in structural cells, such as airway smooth muscle cells and epithelial cells, and in inflammatory and immune cells, such as eosinophils and dendritic cells. They function in a variety of airway responses related to the pathophysiology of inflammatory diseases, including allergic asthma. In the present review, we discuss the roles of ionotropic TRPV1 and ASICs and metabotropic OGR1-family G protein-coupled receptors in the airway inflammation and AHR in asthma and respiratory diseases.

The effects of concomitant GERD, dyspepsia, and rhinosinusitis on asthma symptoms and FeNO in asthmatic patients taking controller medications.

BACKGROUND: Losing the sense of smell, which suggests eosinophilic rhinosinusitis, is a subjective symptom, sometimes reported in asthmatic patients taking controller medication. Upper abdominal symptoms, suggesting gastroesophageal reflux disease (GERD) or functional dyspepsia, occur also in these patients. However, the relationship between these symptoms, concomitant with asthma, and the intensity of eosinophilic airway inflammation remains obscure. OBJECTIVE: To assess the symptoms of asthma and rhinosinusitis, and to examine the relationship between the symptoms and bronchial inflammation, a new questionnaire, the G scale, was developed. To investigate the effects of GERD, dyspepsia, and rhinosinusitis on asthma symptoms and bronchial inflammation, the symptoms of asthma and rhinosinusitis obtained by the G scale, upper abdominal symptoms obtained by the modified F scale, a questionnaire for GERD and dyspepsia, and fractional exhaled nitric oxide (FeNO) were analyzed. METHODS: A prospective, observational study was performed in four hospitals in Gunma prefecture, and a retrospective analysis was done using data obtained from five hospitals in Gunma prefecture and Fukui prefecture, Japan. A total of 252 patients diagnosed as having asthma participated in the prospective study. RESULTS: The frequency of daytime phlegm or losing the sense of smell had a positive correlation with FeNO levels in asthmatic patients taking controller medication. Upper abdominal symptoms, as well as symptoms suggesting rhinitis, were well correlated with asthma symptoms. However, neither upper abdominal symptoms nor rhinitis symptoms increased FeNO levels, which reflect eosinophilic airway inflammation during treatment for asthma. On the other hand, the degree of upper abdominal symptoms or dyspepsia symptoms had a weak but significant negative correlation with FeNO levels. CONCLUSION: Daytime phlegm and losing the sense of smell suggest that eosinophilic airway inflammation persists, despite anti-inflammatory therapy, in patients with asthma. Although rhinitis and GERD made the subjective symptoms of asthma worse, they did not seem to enhance eosinophilic airway inflammation.

Acidic pH increases cGMP accumulation through the OGR1/phospholipase C/Ca(2+)/neuronal NOS pathway in N1E-115 neuronal cells.

Neuronal NO synthase (nNOS)-mediated cGMP accumulation has been shown to affect a variety of neuronal cell activities, regardless of whether they are detrimental or beneficial, depending on the amount of their levels, under the physiological and pathological situations. In the present study, we examined the role of proton-sensing G protein-coupled receptors (GPCRs), which have been identified as new pH sensors, in the acidic pH-induced nNOS/cGMP activity in N1E-115 neuronal cells. In this cell line, ovarian cancer G protein-coupled receptor 1 (OGR1) and G protein-coupled receptor 4 (GPR4) mRNAs are expressed. An extracellular acidic pH increased cGMP accumulation, which was inhibited by nNOS-specific inhibitors. Acidic pH also activated phospholipase C/Ca(2+) pathways and Akt-induced phosphorylation of nNOS at S1412, both of which have been shown to be critical regulatory mechanisms for nNOS activation. The acidic pH-induced activation of the phospholipase C/Ca(2+) pathway, but not Akt/nNOS phosphorylation, was inhibited by small interfering RNA specific to OGR1 and YM-254890, an inhibitor of Gq/11 proteins, in association with the inhibition of cGMP accumulation. Moreover cGMP accumulation was inhibited by 2-aminoethoxydiphenyl borate, an inhibitor of inositol 1,4,5-trisphosphate channel; however, it was not by wortmannin, a phosphatidylinositol 3-kinase inhibitor, which inhibited Akt/nNOS phosphorylation. In conclusion, acidic pH stimulates cGMP accumulation preferentially through the OGR1/Gq/11 proteins/phospholipase C/Ca(2+)/nNOS in N1E-115 neuronal cells. Akt-mediated phosphorylation of nNOS, however, does not appreciably contribute to the acidification-induced accumulation of cGMP.

Safety and efficacy of high-dose leukocytapheresis in patients with refractory asthma.

OBJECTIVE AND DESIGN: An open-label, non-randomized, single-arm study was performed to investigate the safety and efficacy of high-dose leukocytapheresis (pulse LCAP) for refractory asthma. SUBJECTS: Six patients who fulfilled the ATS workshop criteria for refractory asthma were enrolled and completed this clinical study. TREATMENT: After 4 weeks of observation, pulse LCAP using a large LCAP filter, Cellsorba(®) CS-180S, was performed twice with a 1-week interval at a target dose of 5 L per treatment session. METHODS: The clinical response was assessed by monitoring the peak expiratory flow rate (PEFR) twice a day. The asthma control test (ACT) was used to evaluate the condition of asthma symptoms. The fraction of exhaled nitric oxide (FeNO) as a biomarker for eosinophilic airway inflammation was measured using a chemiluminescence analyzer. RESULTS: PEFR in the morning or the evening and the sum total of the score on the ACT were increased after two consecutive sessions of pulse LCAP. FeNO decreased after pulse LCAP. CONCLUSIONS: The results suggest the efficacy of pulse LCAP for refractory asthma.

Proton-sensing ovarian cancer G protein-coupled receptor 1 on dendritic cells is required for airway responses in a murine asthma model.

Ovarian cancer G protein-coupled receptor 1 (OGR1) stimulation by extracellular protons causes the activation of G proteins and subsequent cellular functions. However, the physiological and pathophysiological roles of OGR1 in airway responses remain largely unknown. In the present study, we show that OGR1-deficient mice are resistant to the cardinal features of asthma, including airway eosinophilia, airway hyperresponsiveness (AHR), and goblet cell metaplasia, in association with a remarkable inhibition of Th2 cytokine and IgE production, in an ovalbumin (OVA)-induced asthma model. Intratracheal transfer to wild-type mice of OVA-primed bone marrow-derived dendritic cells (DCs) from OGR1-deficient mice developed lower AHR and eosinophilia after OVA inhalation compared with the transfer of those from wild-type mice. Migration of OVA-pulsed DCs to peribronchial lymph nodes was also inhibited by OGR1 deficiency in the adoption experiments. The presence of functional OGR1 in DCs was confirmed by the expression of OGR1 mRNA and the OGR1-sensitive Ca(2+) response. OVA-induced expression of CCR7, a mature DC chemokine receptor, and migration response to CCR7 ligands in an in vitro Transwell assay were attenuated by OGR1 deficiency. We conclude that OGR1 on DCs is critical for migration to draining lymph nodes, which, in turn, stimulates Th2 phenotype change and subsequent induction of airway inflammation and AHR.

Prevalence of asthma symptoms based on the European Community Respiratory Health Survey questionnaire and FENO in university students: gender differences in symptoms and FENO.

BACKGROUND: The fractional concentration of nitric oxide in exhaled air (FENO) is used as a biomarker of eosinophilic airway inflammation. FENO is increased in patients with asthma. The relationship between subjective asthma symptoms and airway inflammation is an important issue. We expected that the subjective asthma symptoms in women might be different from those in men. Therefore, we investigated the gender differences of asthma symptoms and FENO in a survey of asthma prevalence in university students. METHODS: The information about asthma symptoms was obtained from answers to the European Community Respiratory Health Survey (ECRHS) questionnaire, and FENO was measured by an offline method in 640 students who were informed of this study and consented to participate. RESULTS: The prevalence of asthma symptoms on the basis of data obtained from 584 students (266 men and 318 women), ranging in age from 18 to 24 years, was analyzed. Wheeze, chest tightness, an attack of shortness of breath, or an attack of cough within the last year was observed in 13.2% of 584 students. When 38.0 ppb was used as the cut-off value of FENO to make the diagnosis of asthma, the sensitivity was 86.8% and the specificity was 74.0%. FENO was ≥ 38.0 ppb in 32.7% of students. FENO was higher in men than in women. The prevalence of asthma symptoms estimated by considering FENO was 7.2%; the prevalence was greater in men (9.4%) than women (5.3%). A FENO ≥ 38.0 ppb was common in students who reported wheeze, but not in students, especially women, who reported cough attacks. CONCLUSIONS: The prevalence of asthma symptoms in university students age 18 to 24 years in Japan was estimated to be 7.2% on the basis of FENO levels as well as subjective symptoms. Gender differences were observed in both FENO levels and asthma symptoms reflecting the presence of eosinophilic airway inflammation. TRIAL REGISTRATION NUMBER: UMIN000003244.

Extracellular acidification induces connective tissue growth factor production through proton-sensing receptor OGR1 in human airway smooth muscle cells.

Asthma is characterized by airway inflammation, hyper-responsiveness and remodeling. Extracellular acidification is known to be associated with severe asthma; however, the role of extracellular acidification in airway remodeling remains elusive. In the present study, the effects of acidification on the expression of connective tissue growth factor (CTGF), a critical factor involved in the formation of extracellular matrix proteins and hence airway remodeling, were examined in human airway smooth muscle cells (ASMCs). Acidic pH alone induced a substantial production of CTGF, and enhanced transforming growth factor (TGF)-ß-induced CTGF mRNA and protein expression. The extracellular acidic pH-induced effects were inhibited by knockdown of a proton-sensing ovarian cancer G-protein-coupled receptor (OGR1) with its specific small interfering RNA and by addition of the G(q/11) protein-specific inhibitor, YM-254890, or the inositol-1,4,5-trisphosphate (IP(3)) receptor antagonist, 2-APB. In conclusion, extracellular acidification induces CTGF production through the OGR1/G(q/11) protein and inositol-1,4,5-trisphosphate-induced Ca(2+) mobilization in human ASMCs.

Lysophosphatidic acid inhibits CC chemokine ligand 5/RANTES production by blocking IRF-1-mediated gene transcription in human bronchial epithelial cells.

Lysophosphatidic acid (LPA) is a phospholipid mediator that exerts a variety of biological responses through specific G-protein-coupled receptors (LPA(1)-LPA(5) and P2Y5). LPA is thought to be involved in airway inflammation by regulating the expression of anti-inflammatory and proinflammatory genes. Chemokines such as CCL5/RANTES are secreted from airway epithelium and play a key role in allergic airway inflammation. CCL5/RANTES is a chemoattractant for eosinophils, T lymphocytes, and monocytes and seems to exacerbate asthma. We stimulated CCL5/RANTES production in a human bronchial epithelial cell line, BEAS-2B, with IFN-γ and TNF-α. When LPA was added, CCL5/RANTES mRNA expression and protein secretion were inhibited, despite the presence of IFN-γ and TNF-α. The LPA effect was attenuated by Ki16425, a LPA(1)/LPA(3) antagonist, but not by dioctylglycerol pyrophosphate 8:0, an LPA(3) antagonist. Pertussis toxin, the inhibitors for PI3K and Akt also attenuated the inhibitory effect of LPA on CCL5/RANTES secretion. We also identify the transcription factor IFN regulatory factor-1 (IRF-1) as being essential for CCL5/RANTES production. Interestingly, LPA inhibited IFN-γ and TNF-α-induced IRF-1 activation by blocking the binding of IRF-1 to its DNA consensus sequence without changing IRF-1 induction and its nuclear translocation. Ki16425, pertussis toxin, and PI3K inhibitors attenuated the inhibitory effect of LPA on IRF-1 activation. Our results suggest that LPA inhibits IFN-γ- and TNF-α-induced CCL5/RANTES production in BEAS-2B cells by blocking the binding of IRF-1 to the CCL5/RANTES promoter. LPA(1) coupled to G(i) and activation of PI3K is required for this unique effect.

Protective effect of resolvin E1 on the development of asthmatic airway inflammation.

Resolvin E1 (RvE1) is an anti-inflammatory lipid mediator derived from the omega-3 fatty acid eicosapentaenoic acid (EPA), and strongly acts in the resolution of inflammation. We previously reported that RvE1 dampens airway inflammation and hyperresponsiveness in a murine model of asthma. In the present study, to elucidate the effects of RvE1 on the development of asthmatic airway inflammation, we investigated whether RvE1 acts on different phases of an OVA-sensitized and -challenged mouse model of asthma. RvE1 treatments at the time of either OVA sensitization or at the time of OVA challenge were investigated and compared with RvE1 treatments at the time of both OVA sensitization and challenge. After RvE1 was administered to mice intraperitoneally at the time of both OVA sensitization and challenge, there were decreases in airway eosinophil and lymphocyte recruitment, as well as a reduction in Th2 cytokine and airway hyperresponsiveness. RvE1 treatment at the time of either OVA sensitization or challenge also improved AHR and airway inflammation. Our results suggest that RvE1 acts on several phases of asthmatic inflammation and may have anti-inflammatory effects on various cell types.

Extracellular acidification stimulates IL-6 production and Ca(2+) mobilization through proton-sensing OGR1 receptors in human airway smooth muscle cells.

The asthmatic airway has been shown to be an acidic environment that may be involved in the pathophysiological features of asthma. However, the mechanism by which an acidic pH modulates the cellular activities involved in the asthmatic airway remains elusive. Here, we characterized acidic pH-induced actions in human airway smooth muscle cells (ASMCs). Extracellular acidification stimulates the mRNA expression and protein production of IL-6, a proinflammatory cytokine, in association with the phosphorylation of extracellular signal-regulated kinase (ERK) and p38MAPK, reflecting the activation of the enzymes. Acidification-induced cytokine production was inhibited by inhibitors of ERK and p38MAPK. Acidification also increased intracellular Ca(2+) concentration, which was accompanied by cell rounding, most likely reflecting contraction. In ASMCs, OGR1 is expressed at by far the highest levels among proton-sensing G protein-coupled receptors. The knockdown of OGR1 and G(q/11) protein with their specific small interfering RNAs and an inhibition of G(q/11) protein with YM-254890 attenuated the acidification-induced actions. We conclude that extracellular acidification stimulates IL-6 production and Ca(2+) mobilization through proton-sensing OGR1 receptors/G(q/11) proteins in human ASMCs.

JNK1 and JNK2 differently regulate IL-12 production in THP-1 macrophage cells.

Macrophages play a key role in initiating the innate responses to infection by secreting cytokines such as interleukin-12 (IL-12). This study defined the distinct regulation of lipopolysaccharide (LPS)-mediated IL-12 production by c-jun NH(2)-terminal kinase (JNK)1 and JNK2 isoforms in human macrophages. Knockdown of JNK1 and JNK2 by small interference RNA (siRNA) reduced and enhanced LPS-induced IL-12 p40 production in THP-1 macrophage cells, respectively. The simultaneous knockdown of JNK1 and JNK2 augmented LPS-induced IL-12 production as well as a specific JNK inhibitor. In addition, transfection of siRNA against phosphoinositide 3-kinase (PI3K) p110beta attenuated LPS-induced IL-12 production and JNK1 phosphorylation, while not affecting JNK2 phosphorylation. These findings indicate that JNK1- and JNK2-mediated signaling plays a positive and a negative role, respectively, in LPS-induced IL-12 production and PI3K p110beta controls LPS-induced JNK1 activation, not JNK2 activation, resulting in the positive regulation of IL-12 production in THP-1 macrophage cells.

Chelation of extracellular calcium-induced cell death was prevented by glycogen synthase kinase-3 inhibitors in PC12 cells.

Calcium ion is a secondary messenger that mediates a variety of physiological responses of neurons, including cell survival responses. To determine the role of calcium in regulating neuronal survival and death, we examined whether chelation of extracellular calcium with EGTA induces caspase-dependent apoptotic cell death and whether glycogen synthase kinase-3 is involved in EGTA-induced cell death in PC12 cells. EGTA increased apoptotic cell death with morphological changes characterized by cell shrinkage and nuclear condensation and fragmentation accompanied by caspase activation. EGTA increased GRP78 protein expression, suggesting that EGTA induces ER stress. Glycogen synthase kinase-3 inhibitors prevented EGTA-induced apoptosis. In addition, nerve growth factor and insulin growth factor-I completely blocked EGTA-induced cell death. Moreover, caspase-3 activation was inhibited by glycogen synthase kinase-3 inhibitors. These results suggest that chelation of extracellular calcium with EGTA induces caspase-dependent apoptosis, and the activation of glycogen synthase kinase-3 is involved in the death of PC12 cells.

Multiple lung metastases presenting as ground-glass opacities in a pulmonary adenocarcinoma: a case report.

INTRODUCTION: Focal ground-glass opacity on computed tomography suggests several disorders including inflammatory disease, fibrosis, or a primary lung neoplastic lesion, metastatic lung tumor. CASE PRESENTATION: The case of a 55-year-old female presenting with adenocarcinoma of the lung is herein reported. Computed tomography of the chest revealed a primary mass lesion in the upper lobe of the right lung and multiple metastases presenting as ground-glass opacities. Macroscopic metastases were observed in the bone, the hilar and mediastinal lymph nodes, and another lobe. This case was advanced lung cancer. We assumed that the multiple ground-glass opacity lesions were metastasis in the lungs. Chest CT revealed a partial response of the primary site and the multiple ground-glass opacities after systemic chemotherapy. CONCLUSION: A metastatic lung tumor showing ground-glass opacity is uncommon. It is quite difficult to distinguish between multiple primary lung cancers and intrapulmonary metastasis when patients present with multiple lung nodules. A lot of clinical information is therefore required to make an accurate diagnosis in such cases.

Resolvin E1 as a novel agent for the treatment of asthma.

BACKGROUND: Asthma is characterized by airway hyperresponsiveness and chronic airway inflammation. Inflammatory cells, including eosinophils and lymphocytes, infiltrate peribronchial tissue in patients with asthma. Resolvin E1 (RvE1) is an anti-inflammatory lipid mediator derived from the omega-3 fatty acid, eicosapentaenoic acid, and has been shown to be involved in resolving inflammation. Although little is known about the actions of RvE1 in the resolution of inflammation due to asthma, recent studies in a mouse model have shown the possibilities of RvE1 in asthma. OBJECTIVE/METHODS: We review the current understanding of the mechanism of RvE1 action in connection with asthma pathogenesis and treatment. RESULTS/CONCLUSION: Findings provide evidence for the use of RvE1 as a pivotal counter-regulatory signal in allergic inflammation and offer the possibility of novel multi-pronged therapeutic approaches for human asthma.

PI3K p110beta positively regulates lipopolysaccharide-induced IL-12 production in human macrophages and dendritic cells and JNK1 plays a novel role.

The PI3K family is thought to participate in TLR signaling, and it has been reported to be a negative regulator of TLR-mediated production of IL-12, a key inducer of Th1 responses. However, the role of individual PI3K subtypes in IL-12 production remains obscure. We defined the distinct regulation of LPS-mediated IL-12 production by p110alpha and p110beta catalytic subunits of PI3K in human APCs. We observed that knockdown of PI3K p110beta by small interfering RNA (siRNA) suppressed both LPS-induced IL-12 protein production and mRNA expression in monocyte-derived macrophages and dendritic cells (DCs). Knockdown of PI3K p110alpha by siRNA reduced LPS-induced IL-12 protein production in both cell types. Conversely, knockdown of PI3K p110alpha suppressed LPS-induced IL-12 mRNA expression in monocyte-derived macrophages but minimally affected monocyte-derived DCs. PI3K p110beta siRNA inhibited JNK activation, but not p38 MAPK or ERK activation, stimulated by LPS, while PI3K p110alpha siRNA did not affect LPS-induced JNK, p38 MAPK, or ERK activation in both cell types. Transfection of siRNA against JNK1, JNK2, and both decreased LPS-induced IL-12 production. Furthermore, PI3K p110beta siRNA attenuated LPS-induced JNK1 phosphorylation, while not affecting JNK2 phosphorylation. Our findings indicate that PI3K p110beta positively controls LPS-induced IL-12 production through the JNK1-dependent pathway in human macrophages and DCs.