Leukotriene D4 induces chemotaxis in human eosinophilc cell line, EoL-1 cells via CysLT1 receptor activation

Numerous reports have shown that cysteinyl leukotrienes (CysLTs) contribute to tissue accumulation of eosinophils in allergic airway inflammation. To date, only a few studies have reported that CysLTs promote chemotactic activity of human eosinophils in vitro. The purpose of this study was to investigate whether CysLTs promote chemotaxis in the human eosinophilic cell line, EoL-1. EoL-1 cells were induced to differentiate into mature eosinophil-like cells via incubation with butyric acid and cytokines (IL-3, IL-5 and GM-CSF). The chemotactic activity of the differentiated EoL-1 cells was assessed using the commercial cell migration assay kit. LTD₄ elicited dose-related chemotactic activity in the differntiated EoL-1 cells in the range of 1–100 nM. A typical bell-shaped dose-response curve was observed with optimal activity at 10 nM. The chemotactic activity elicited by LTD₄ (10 nM) was significantly inhibited by montelukast (control, 345 ± 19.2 × 10³ RFU; LTD₄ 10 nM alone, 511 ± 39.2 × 10³ RFU; LTD₄ 10 nM plus montelukast 100 nM, 387 ± 28.2 × 10³ RFU). LTD₄ induces migration in eosinophilic cells via activation of CysLT1 receptor. The present in vitro model may be useful for elucidation of the mechanism underlying CysLT-induced tissue eosinophilia.

Effects of Cetirizine on Substance P Release in Patients with Perennial Allergic Rhinitis

To evaluate the effect of cetirizine hydrochloride on substance P release in allergic rhinitis, we performed a single-blind placebo-controlled study of 14 patients with perennial allergic rhinitis (7 treated with cetirizine and 7 with placebo). After an initial nasal allergen challenge with lavages, the subjects received treatment with placebo or cetirizine hydrochloride (10 mg by mouth daily) for 1 week, followed by the second nasal allergen challenge with lavages. The levels of albumin, histamine, and substance P in nasal lavages before and after allergen challenge were quantified by enzyme-linked immunosorbent assay. Pretreatment of subjects with cetirizine reduced the level of substance P induced by antigen challenge, but did not significantly reduce levels of histamine. These results suggest that cetirizine may reduce nasal neurogenic inflammation by modulating the release of substance P in allergic rhinitis.

Expression and localization of GPR99 in human nasal mucosa

OBJECTIVE

The cysteinyl leukotrienes (CysLTs) are lipid mediators that have been implicated in the pathogenesis of allergic rhinitis. Pharmacological studies of CysLTs indicate that two classes of receptors, CysLT₁R and CysLT₂R exist. CysLT₁R is a high affinity LTD₄ receptor with lower affinity for LTC₄, and a CysLT₁R antagonist is currently used to treat asthma and allergic rhinitis. CysLT₂R binds to LTC₄ and LTD₄ with equal affinity. GPR99 (also called GPR80), previously described as an oxoglutarate receptor (OXGR1), has recently emerged as a potential novel receptor with LTE₄. The purpose of this study was to determine the expression and localization of GPR99 protein in the human nasal mucosa.

METHODS

Human turbinates were obtained after turbinectomy from 12 patients with nasal obstruction refractory to medical therapy. GPR99 protein expression was evaluated by western blotting, and the specific cells expressing GPR99 protein identified by immunostaining using a commercial anti-GPR99 (OXGR1) monoclonal antibody.

RESULTS

A 38-kDa band was detected in the western blots of human nasal samples by using the anti-GPR99 monoclonal antibody. We did not find any differences in GPR99 protein levels between allergic and non-allergic nasal mucosa. The immunohistochemical studies revealed that the anti-GPR99 monoclonal antibody mainly labeled vascular smooth muscle cells in the nasal mucosa.

CONCLUSION

These immunohistochemical results suggest that GPR99 may play some roles in the vascular response. Further functional studies will be necessary to clarify the biological significance of the GPR99 receptor in nasal vasculature.

A Clinical Study of Maxillary Sinus Squamous Cell Carcinoma

We report a retrospective study of 26 patients with maxillary sinus squamous cell carcinoma who were treated at the Sapporo Medical University between January 2002 and December 2008. The 5-year local control rate was 85.7% in patients with stage T2-3 disease and 61.0% in patients with stage T4a disease. The overall 5-year survival rate was 71.3% and the 5-year disease-specific survival rate was 79.9%. The 5-year disease-specific survival rate was 100% in patients with T2-3 disease and 44.4% in patients with T4 disease. The 5-year disease-specific survival rate was 76.3% in patients with N0 disease and 87.5% in patients with N+ disease. Five patients died of stage T4a disease. Two died of uncontrolled tumors at the primary site and 3 patients died of lung metastasis. We should consider another approach for the treatment of patients with advanced maxillary sinus carcinoma in the future.

Nasal Mucosal Expression of the Receptors for Inflammatory Chemical Mediators

The nasal allergic response is a complex process involving interactions between many chemical mediators such as histamine, bradykinin, cysteinyl leukotrienes, platelet-activating factor, prostaglandin D2 and thromboxane A2. The actions of these chemical mediators are facilitated by specific cell surface receptors that are coupled to G-proteins. Current therapeutic strategies against nasal allergic responses are mainly based on drugs that target these chemical mediators. To understand the role of these chemical mediators in allergic rhinitis, determining the identity and distribution of their receptors is of considerable interest. We have examined the expression and localization of the receptors for these chemical mediators in human nasal mucosa. Here, we review our data on the expression and localization of these receptors in allergic rhinitis, and we discuss the roles of chemical mediators in allergic rhinitis.

Role of Cysteinyl Leukotrienes in Allergic Rhinitis

Cysteinyl leukotrienes (CysLTs) are lipid mediators that have been implicated in the pathogenesis of allergic rhinitis. Pharmacological studies using CysLTs indicate that two classes of receptor exist: CysLT1 receptor (CysLT1R) and CysLT2 receptor (CysLT2R). The CysLT1R is a high-affinity leukotriene D4 receptor with lower affinity for leukotriene C4 that is sensitive to the CysLT1R antagonist currently used to treat asthma and allergic rhinitis. Our previous immunohistochemical and autoradiographic studies have demonstrated the presence of anti-CysLT1R antibodies labeled in eosinophils, mast cells, macrophages, neutrophils and vascular endothelial cells in human nasal mucosa. Furthermore, we have revealed that the novel radioactive CysLT1R antagonist [3H]-pranlukast bound specifically to CysLT1R in human inferior turbinates and its binding sites were localized to vascular endothelium and the interstitial cells. These data suggest that the major targets of CysLT1R antagonists in allergic rhinitis are the vascular bed and infiltrated leukocytes such as mast cells, eosinophils and macrophages. Clinical trials have demonstrated that CysLT1R antagonists are as effective as antihistamines for the treatment of allergic rhinitis; however, they are less effective than intranasal steroids. The use of CysLT1R antagonists in combination with antihistamines has generally resulted in greater efficacy than when these agents were used alone.

Immunohistochemical localization of alpha and beta adrenergic receptors in the human nasal turbinate

OBJECTIVE

Adrenergic receptors (ARs) include four general types (α1, α2, β1 and β2), which are found in different target tissues. α-AR agonists are commonly used for decongestant therapy of upper airway diseases. In order to clarify the roles of AR subtypes in the upper airways, we investigated the localization of these receptors by immunohistochemistry.

METHODS

Human turbinates were obtained after turbinectomy from 12 patients with nasal obstruction refractory to medical therapy. The specific cells expressing α- and β-AR proteins were identified by immunostaining using an anti-human AR subtype-specific antibodies (α1A-, α1D-, α2C- and β2-ARs) antibody.

RESULTS

Immunohistochemical analysis revealed that immunoreactivities for α1D- and β2-ARs were densely distributed in submucosal glands. In contrast, immunoreactivities for α1A- and 2C-ARs were densely distributed in vascular smooth muscle.

CONCLUSION

Our results suggested that adrenergic receptor (AR) subtypes had different roles in upper airway diseases, such as allergic rhinitis and nonallergic rhinitis.

[A relationship between birch pollen counts and meteorological factors in Sapporo]

Occurrence of airborne pollen in Sapporo has been studied for 19 years during the period between 1995 and 2013. There are wide year-to-year variations in the quantities of birch pollens. A simple linear regression with the least squares method was used for studying correlations between the annual quantities of birch pollens and the meteorological factors. A significant positive correlation was found between the hours of sunlight in June of the preceding year and the annual birch pollen concentrations with the correlation coefficient, R = 0.667. Also, we found the significant positive correlation between the hours of sunlight in March and the annual birch pollen concentrations with the correlation coefficient, R = 0.684. These results suggest that the atmospheric birch pollen counts can be predicted from meteorological factors.

[Questionnaire about the intake of and hypersensitivity to fruits, vegetables and nuts including birch pollen related foods]

BACKGROUND

In Hokkaido and Scandinavia, birch pollen allergic persons are common and they often report oral and pharyngeal hypersensitivity to fruits and vegetables (oral allergy syndrome, OAS), because of immunological cross-reactivity. In Scandinavia, nuts as well as Rosaceae fruits such as apples were the foods most often reported to elicit symptoms. On the other hand, nuts are minor foods causing hypersensitivity in Japan. Even in Japan, regional differences of foods causing hypersensitivity have been reported, which may be related to the regional differences of elementary habit and pollen dispersion. In the present study, we evaluated the intake history of the foods and the frequency of food hypersensitivity in adults from the general population.

METHODS

Three hundreds and thirty nine subjects (20-67 years old) took part in the study. With a questionnaire survey, we asked them about their intake history and hypersensitive symptoms for 33 kinds of fruit, vegetables, and nuts.

RESULTS

30% of subjects had eaten Brazil nuts, 80% had eaten pomegranates, and 81% had eaten hazelnuts. And over 95% of subjects had eaten the other 30 foods. Those who had lived in Hokkaido for more than 20 years had a higher frequency of plum consumption than the others. Those who had lived in Hokkaido for more than 20 years had a lower frequency of loquat, fig and pomegranate consumption than the others. Food hypersensitivity was found in 52 subjects (15.3%). The most common symptom was OAS (46 subjects, 13.6%), and foods most frequently causing OAS were peach (21 subjects, 6.2%), cherry (19 subjects, 5.6%) and apple (17 subjects, 5.0%). 26 subjects (7.7%) reported OAS to Rosaceae fruits. The ratio of having OAS to consuming Rosaceae fruits was 11.0% in the group who had lived in Hokkaido for more than 20 years, which was higher than the group who has lived in Hokkaido for less than 20 years. The intake history of hazelnuts and Brazil nuts was very low, with a correspondingly low frequency of food hypersensitivity associated with these nuts.

CONCLUSION

The frequency of intake and hypersensitivity of some foods differ among different regions.

Localization and up-regulation of cysteinyl leukotriene-2 receptor in human allergic nasal mucosa

BACKGROUND

Cysteinyl leukotrienes (CysLTs) are lipid mediators that have been implicated in the pathogenesis of allergic rhinitis. Pharmacological studies using CysLTs indicate that 2 classes of receptors exist, namely, CysLT1 and CysLT2 receptors. The former class of receptors is sensitive to the CysLT1 antagonists currently used to treat asthma and allergic rhinitis, and its localization has been previously examined by our group using immunohistochemistry and in situ hybridization techniques. We investigated the expression and localization of the CysLT2 receptor in human nasal mucosa by western blot and immunohistochemical analyses.

METHODS

Human turbinates were obtained after turbinectomy from 16 patients with nasal obstruction refractory to medical therapy. To identify the cells expressing the CysLT2 receptor, double immunostaining was performed by using anti-CysLT2 receptor antibody and anti-CD31 (endothelial cell) antibody or anti-smooth muscle actin antibody.

RESULTS

A 39 kDa band was detected on the western blots of human turbinates samples by using the anti-CysLT2 receptor antibody. The expression level of the CysLT2 receptor in patients with nasal allergy was higher than that in patients with non-allergic rhinitis. The immunohistochemical study also showed an intense immunoreactivity for CysLT2 receptor in both vascular endothelial cells and vascular smooth muscles.

CONCLUSIONS

The results indicated that the CysLT2 receptor plays a primary role in the vascular responses in the upper respiratory tract.

Expression and localization of purinergic P2Y(12) receptor in human nasal mucosa

BACKGROUND

Extracellular nucleotides such as ATP and UTP are released from essentially all cells, and they interact with cell surface P2 receptors to produce a broad range of physiological responses. P2Y12 receptor is the major platelet receptor that mediates ADP-induced aggregation, P2Y12 receptor inhibitors such as clopidogrel and prasugrel inhibit platelet aggregation, and thus, they are used in the treatment and prevention of coronary artery disease. Recently, studies have focused on the P2Y12 receptor as a receptor for leukotriene E4 (LTE4), because this receptor is required for LTE4-mediated pulmonary inflammation. To establish the presence of P2Y12 receptor in human nasal mucosa, we investigated the expression and the localization of the P2Y12 receptor in human nasal mucosa.

METHODS

Human turbinates were obtained by turbinectomy from 12 patients with nasal obstruction refractory to medical therapy. The expression of P2Y12 receptor was evaluated by RT-PCR, western blotting, and immunohistochemical analysis.

RESULTS

RT-PCR analysis of total RNA extracted from human nasal turbinate, primary cultured human nasal epithelial cells and nasal vascular endothelial cells demonstrated the expression of P2Y12 receptor mRNA. A band of approximately 55 kDa was detected in human turbinates by western blot analysis using anti-P2Y12 receptor antibody. We could not find any differences between P2Y12 receptor levels in allergic and non-allergic nasal mucosa. An immunohistochemical study revealed that epithelial cells, submucosal glands and vascular endothelial cells showed intense immunoreactivity for the P2Y12 receptor.

CONCLUSIONS

The results may have important clinical implications for understanding the role of P2Y12 receptor in upper airway diseases such as allergic rhinitis and non-allergic rhinitis.

Cytotoxicity of a novel indoloquinone eo9 in hypoxic non-small-cell lung-cancer cell-lines

3-Hydroxymethyl-5-aziridinyl-1-methyl-[1H-indole-4,7-dione]-prop-beta-en -alpha-ol (EO9) is a bioreductive anticancer agent active for non-small cell lung cancer (NSCLC) and structurally related to mitomycin C (MMC). DT-diaphorase (DTD) is regarded as a two electron reductase that plays an important role in the biotransformation of MMC to antitumor metabolites. To evaluate the role of DTD as a bioactivator of EO9 in NSCLC cell lines under oxic and hypoxic conditions, we examined the inhibitory effect of dicumarol which was regarded as a selective inhibitor of DTD on the sensitivity to EO9 in vitro. In this study, we used an MMC-resistant NSCLC cell line (PC-9/MC4) which was established from a PC-9 cell line as a parent cell line by continuous exposure to MMC in our laboratory. We reported previously that the subline PC-9/MC4 was 6.7-fold more resistant to MMC than PC-9 with decreased DTD activity. The IC50 value of PC-9 against EO9 was significantly increased by co-incubation with dicumarol under oxic conditions. EO9 was more cytotoxic against PC-9/MC4 than against PC-9 cells and the enhancement was impaired by tempol under hypoxic conditions. These findings suggest a suppressive role of DTD against one-electron reduction pathway in the bioactivation of EO9 under hypoxic conditions and EO9 may be more active against oxygen-deficient solid tumors especially in MMC-resistant NSCLC cells with low levels of DTD activity.

Stimulation of beta-adrenoceptor enhances sensitivity to cisplatin in non-small cell lung cancer cell lines

Cisplatin is a key drug in chemotherapy for lung cancer. It has been reported that intracellular accumulation of cisplatin is an important step as a determinant for resistance to cisplatin, which may be modulated by Na+, K+-ATPase activity. And it has been reported that beta-adrenoceptor agonists modulate the Na+, K+-ATPase in some organs. In this study, the effects of a beta-adrenoceptor agonist and an antagonist on membrane Na+, K+-ATPase activity were evaluated using human non-small cell (NSCLC) lung cancer cell lines. In the NSCLC cell lines, sensitivity to cisplatin was improved by treatment with isoproterenol. Na+, K+-ATPase was activated and intracellular accumulation of cisplatin increased with the treatment. But the antagonist, propranolol, did not modulate sensitivity to cisplatin or Na+, K+-ATPase activity. These results suggest that beta-adrenoceptors may be one of the determinant for sensitivity to cisplatin in NSCLC, but endogenous catecholamine dose not play a role in the intracellular accumulation of cisplatin in these cell lines. Exogenous beta-adrenoceptor agonists may improve the antitumor effect of chemotherapy involving cisplatin.

POU2AF1(+) follicular helper T (Tfh) cells in obstructive sleep apnea syndrome (OSAS) (69.3)

OSAS is attributable to periodic collapse of the upper airway due to adenotonsillar hypertrophy, featuring prominent germinal centers and wide interfollicular zones. However, the mechanism is still unclear. Here we present the possible involvement of Tfh cells in the pathogenesis of OSAS as indicated by comprehensive analysis of tonsillar lymphocytes of OSAS patients. The results revealed that tonsillar Tfh cells were plentiful in OSAS compared to recurrent tonsillitis (RT) without any discrepancy of T-cell components between the tonsils of OSAS and RT patients, indicating a ‘Tfh shift’ in OSAS tonsils. In addition, in vitro experiments delineated a unique function of the Tfh cells of OSAS, which could help expand the number of naive B cells and, more extensively, memory B cells, which allowed the Tfh cells to produce larger amounts of IL-4 and IFN-γ. Microarray studies newly identified transcripts characterizing the Tfh cells, including TIGIT and POU2AF1 regulating CXCR5 of B cells. Indeed, B-cell expansion was under the control of TIGIT, and large numbers of POU2AF1(+) Tfh cells were observed in and outside of germinal centers of OSAS tonsils. Overall these findings indicate that POU2AF1(+) Tfh cells cooperate with regional B-cell subsets to induce lymphoid hyperplasia.Focusing on the TIGIT-selective regulation of POU2AF1(+) Tfh cells, further investigations may provide a new modality for a noninvasive approach to treatment of this condition.

Arachidonate 5-lipoxygenase establishes adaptive humoral immunity by controlling primary B cells and their cognate T-cell help

In this study, we report the unique role of arachidonate 5-lipoxygenase (Alox5) in the regulation of specific humoral immune responses. We previously reported an L22 monoclonal antibody with which human primary resting B cells in the mantle zones of lymphoid follicles are well-defined. Proteomics analyses enabled identification of an L22 antigen as Alox5, which was highly expressed by naive and memory B cells surrounding germinal centers. Cellular growth of mantle cell lymphoma cells also seemed to depend on Alox5. Alox5(-/-) mice exhibited weak antibody responses specific to foreign antigens at the initial and recall phases. This was probably attributable to the low number of follicular and memory B cells and the functional loss of interleukin-21-mediated responses of follicular B cells. Moreover, Alox5(-/-) mice could not fully foster the development of follicular B helper T (Tfh) cells even after immunization with foreign antigens. Further experiments indicated that Alox5 affected mortality in experimentally induced enterocolitis in germ-prone circumstances, indicating that Alox5 would endow immunologic milieu. Our results illustrate the novel role of Alox5 in adaptive humoral immunity by managing primary B cells and Tfh cells in vivo.

[Relationship between IgE antibodies to recombinant allergens rBet v 1 and rBet v 2 and food causing oral allergy syndrome in cases of birch-pollen allergy]

BACKGROUND

Persons allergic to birch pollen often report oral and pharyngeal hypersensitivity to fruit and vegetables, such as apples and peaches due to immunological cross-reactivity, or oral allergy syndrome (OAS) sometimes accompanied by systemic reaction. Such cross-reactive antigen reactions involve Bet v 1, the main birch-pollen allergen, and Bet v 2, birch-pollen profilin. We evaluated the food/antigen relationship.

METHODS

Subjects interviewed numbered 60-40 women and 20 men aged 12 to 70 (mean age: 35 years)-suffering OAS episodes and having IgE birch-pollen antibodies. Using CAP scoring we examined IgE antibodies to recombinant Bet v 1 (rBet v 1), recombinant Bet v 2 (rBet v 2), and recombinant Pru p 3 (rPru p 3) a peach lipid transfer protein (LTP). A CAP score of 0.35 or more was considered positive. We evaluated the relationship between recombinant allergens and 9 fruit often involving OAS--apple, peach, cherry, kiwi, pear, melon, plum, strawberry, and watermelon-based on subjects' reports.

RESULTS

Of the 60, all (100%) were rBet v 1-positive, 9 (15%) rBet v 2-positive, and none (0%) rPru p 3-positive. Rose-family fruit-apples, peaches, cherries, pears, plums, and strawberries-often caused OAS regardless of positive or negative rBet v 2 CAP and were associated with rBet v 1. In contrast, more of those who were rBet v 2 CAP-positive had OAS to non-rose-family fruit-melon and watermelon-than those rBet v 2-negative. In rose-family and non-rose-family classification of the 9 fruit, cluster analysis and kappa statistics showed non-rose-family melon, watermelon, and kiwi to be associated with rBet v 2, as were grass and mugwort pollen allergies.

CONCLUSION

Bet v 1 is associated with OAS due to rose-family fruit and Bet v 2 with OAS due to non-rose-family fruit.

Accumulation of CRTH2-positive leukocytes in human allergic nasal mucosa

BACKGROUND

Prostaglandin D2 (PGD2) has been thought to be a potent mediator involved in allergic rhinitis because PGD2 has been recovered from the nasal lavage fluid of patients with allergic rhinitis after allergen provocation and because PGD2 receptor antagonists relieved nasal allergic symptoms in an animal model of allergic rhinitis. The inflammatory effects of PGD2 are exerted through high-affinity interactions with 2 G protein-coupled receptors: D-prostanoid receptor 1 and chemoattractant-homologous receptor expressed on TH2 cells (CRTH2). CRTH2 may mediate the recruitment of leukocytes during a nasal allergic response.

OBJECTIVE

To evaluate the number of CRTH2-expressing cells in allergic and nonallergic human nasal mucosa by means of immunohistochemical analysis.

METHODS

Human turbinates were obtained after turbinectomy from 14 patients with nasal obstruction refractory to medical therapy. To identify cells expressing the CRTH2 protein, double immunostaining was performed using anti-CRTH2 antibody and monoclonal anti-leukocyte antibodies.

RESULTS

The immunohistochemical study revealed that anti-CRTH2 antibody labeled eosinophils, macrophages, mast cells, T lymphocytes, epithelial cells, and submucosal glands in the nasal mucosa. CRTH2 expressions of these leukocytes in allergic nasal mucosa are significantly up-regulated compared with those in nonallergic nasal mucosa.

CONCLUSION

These results suggest that CRTH2 may play an important role in the recruitment of leukocytes into allergic nasal mucosa.

[evaluation of relationships between foods and pollen antigens in peach oral allergy patients -serous specific IgE levels of peach recombinant Antigen-]

PURPOSE

Evaluation of the relationships between foods and pollen allergens in oral allergy syndrome (OAS).

METHODS

Serous level of specific IgE against recombinant peach allergens (rPru p 1, rPru p 3 and rPru p 4) in 17 peach OAS patients were examined by Pharmacia CAP RASTsystem.

RESULTS

In 17 pollinosis patients, the number of patients positive to peach, rPru p 1, rPru p 4 and rPru p 3 RAST were 13 (76%), 14 (82%), 6 (35%) and 0 (0%), respectively. The RAST value of rPru p 1 was significantly correlated with that of natural birch pollen extract (r=0.745, p=0.0003), but not with that of mugwort pollen extract. The RAST value of rPru p 4 was significantly correlated with that of mugwort pollen extract (r=0.602, p=0.0092), but not with that of natural birch pollen extract.

CONCLUSION

Concerning to peach OAS, the most important cross-reactive antigen is Pru p 1 in birch pollinosis, and is Pru p 4 in mugwort pollinosis.

Cysteinyl leukotriene receptor CysLT1 as a novel therapeutic target for allergic rhinitis treatment

BACKGROUND

Cysteinyl leukotrienes (cys-LTs) play an important role in allergic rhinitis because CysLT(1) receptor antagonists relieve the symptoms of allergic rhinitis.

OBJECTIVE

I overview the clinical pharmacology of CysLT(1) receptor antagonists and their potential role in patients with allergic rhinitis.

METHODS

I review the evidence regarding the release of cys-LTs and localization of CysLT(1) receptor on nasal mucosa, and evaluate the clinical efficacy of CysLT(1) receptor antagonist in allergic rhinitis.

RESULTS/CONCLUSION

Immunohistochemical studies show that in allergic rhinitis, the major target of CysLT(1) receptor antagonists are the vascular bed and infiltrated leukocytes such as mast cells, eosinophils and macrophages. CysLT(1) receptor antagonists provide a new opportunity for simultaneous management of allergic diseases of the upper and lower respiratory tract.

Platelet-activating factor (PAF) increases NO production in human endothelial cells-real-time monitoring by DAR-4M AM

BACKGROUND

Platelet-activating factor (PAF) is a potent inflammatory lipid mediator that increases vascular permeability and vasodilation. Several studies have addressed the effect of PAF on nitric oxide (NO) production from microvessels in vivo.

OBJECTIVE

The aim of present study was to evaluate the effect of PAF on NO production in primary cultured human vascular endothelial cells.

METHODS

Human umbilical vein endothelial cells (HUVECs) were loaded with diaminorhodamine-4M acetoxymethyl ester (DAR-4MAM), and the cells were stimulated with PAF. Intracellular NO production was monitored as increase in fluorescence intensity. Also, NO production was visualized at cellular levels using DAR-4M AM and fluorescence imaging.

RESULTS

Significant increases in NO production in HUVECs were soon after the PAF stimulation, reaching a plateau after 10 min of the stimulation. The increase of NO production at 10 min after the stimulation was statistically significant (p<0.05) for 0.01-10 microM PAF. PAF-induced NO production was abolished by pretreatment of HUVECs with a NOS inhibitor N(G)-monomethyl-L-arginine (L-NMMA) or PAF receptor antagonist BN 52021. LysoPAF, the inactive metabolite of PAF, did not exert a significant effect on intracellular NO levels.

CONCLUSIONS

These results provide direct evidence that PAF cause intracellular NO production via activation of PAF receptors in human vascular endothelial cells.

Detection of specific IgE antibodies in sera of Japanese birch-allergic patients using recombinant allergens Bet v 1, Bet v 2 and Bet v 4

BACKGROUND

Birch pollen is the major allergen in pollinosis in northern Japan. IgE reactivity to individual birch pollen allergens has been shown to differ between populations of birch pollen-allergic patients living in different countries. In this study, we examined the IgE profiles to recombinant birch pollen allergens in birch-sensitive patients living in Sapporo.

METHODS

This study used the sera of 40 patients with specific IgE toward birch pollen extract. Their sera were analyzed for specific IgE reactivity to individual birch pollen allergens (recombinant Bet v 1, Bet v 2 and Bet v 4) and natural birch pollen extract using Pharmacia CAP SystemTM.

RESULTS

Of 40 sera with positive CAP results for natural birch pollen extract, 39 (97.5%) had specific IgE towards Bet v 1; 6 (15%) contained specific IgE against Bet v 2. Bet v 4 reactivity was documented in only one subject (2.5%).

CONCLUSIONS

The present data suggest that the specific IgE reactivity profiles to birch pollen allergen in birch-sensitive patients in Sapporo correspond to those in Scandinavia, possibly due to the heavy birch pollen exposure in this area. This observation provides useful information for future birch allergen-specific immunotherapy in Japan.

Agonist- and T(H)2 cytokine-induced up-regulation of cysteinyl leukotriene receptor messenger RNA in human monocytes

BACKGROUND

The cysteinyl leukotrienes (CysLTs) are lipid mediators that have been implicated in the pathogenesis of allergic diseases, and their actions are mediated via specific receptors named CysLT1 receptor (CysLT1R) and CysLT2 receptor (CysLT2R). Little information is known about the role of T(H)2 cytokines in the regulation of both CysLT1R and CysLT2R expression.

OBJECTIVE

To investigate the possible modulation of both CysLT1R and CysLT2R messenger RNA (mRNA) expression, we have developed a real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) assay based on the TaqMan fluorescence method to quantify CysLT1R and CysLT2R mRNA in human monocytes.

METHODS

Human monocytes were stimulated with leukotriene D4 or interleukin (IL) 4 or IL-13, and the levels of CysLT1R and CysLT2R mRNA were measured by the quantitative RT-PCR.

RESULTS

CysLT1R and CysLT2R mRNA was increased after stimulation with leukotriene D4. CysLT1R mRNA was augmented 150-fold after treatment with IL-4; however, no significant increase was observed in CysLT2R mRNA level. IL-13 could induce a biphasic augmentation of CysLT1R mRNA level. In contrast to IL-4, IL-13 enhanced CysLT2R mRNA level, with a maximal effect at 2 hours of incubation.

CONCLUSIONS

CysLT1R and CysLT2R expression can be regulated by CysLT itself and T(H)2 cytokines at the transcriptional level.

Expression and localization of the thromboxane A2 receptor in human nasal mucosa

Thromboxane A2 (TXA2) has been thought a potent mediator involved in allergic rhinitis, because TXA2 was recovered from the nasal lavage fluid of allergic rhinitis patients after allergen provocation and TXA2 receptor antagonists relief nasal allergic symptoms. In order to clarify the expression of TXA2 receptor in human nasal mucosa, we investigated TXA2 receptor mRNA expression and its protein localization by polymerase chain reaction (PCR) and immunohistochemistry, respectively. Human turbinates were obtained after turbinectomy from 10 patients with nasal obstruction refractory to medical therapy. RT-PCR analysis of total RNA from nasal mucosa demonstrated the expression of TXA2 receptor alpha mRNA. The immunohistochemical studies revealed that anti-TXA2 receptor alpha antibody labeled vascular smooth muscle cells, vascular endothelial cells, epithelial cells and submucosal glands in the nasal mucosa. The results may have an important clinical implication for understanding the role of TXA2 receptor on upper airway diseases such as allergic rhinitis and non-allergic rhinitis.

Capsaicin induces the production of IL-6 in human upper respiratory epithelial cells

Capsaicin, a type of alkaloid and the pungent component of chili peppers, is used as a therapeutic drug against allergic rhinitis and also as an index of bronchial hypersensitivity. Capsaicin receptor (TRPV1) expression has been identified in non-neuronal cells as well as neuronal cells. In our previous study, both TRPV1 protein and its gene expression on nasal epithelial cells were confirmed by immunohistochemistry and RT-PCR, respectively. In order to clarify whether or not TRPV1 acts as a functional receptor, we examined the effects of capsaicin on the production of IL-6 from primary cultured human airway epithelial cells at both protein and mRNA levels. Human nasal epithelial cells (HNECs) and normal human bronchial/tracheal epithelial cells (NHBE cells) were stimulated with increasing concentrations of capsaicin and/or pretreatment with capsazepine (TRPV1 antagonist) at 37 degrees C. The supernatant and total RNA were collected at 0, 4, 12, 24 and 48 h after treatment. IL-6 concentration and the IL-6 mRNA level were evaluated by ELISA and real-time PCR, respectively. Capsaicin (10 nM-10 muM) induced production of IL-6 from HNECs and NHBE cells and this effect was inhibited by pretreatment with capsazepine. Our findings suggest that topical application of capsaicin to the airway induces IL-6 production from respiratory epithelial cells via activation of TRPV1.

The MM2-cortical form of sporadic Creutzfeldt-Jakob disease presenting with visual disturbance

A subclass of sporadic Creutzfeldt-Jakob disease (sCJD) characterized by onset with visual symptoms (Heidenhain variant) has been reported to belong to the MM1 or MV1 type according to Parchi's classification. The authors report a 65-year-old woman with MM2-cortical sCJD with slowly progressive visual disturbance as the initial symptom. Diffusion-weighted MRIs revealed hyperintensity in both occipital cortices at an early stage.

Distribution of specific binding sites for cysteinyl leukotriene 1 receptor antagonist in human nasal mucosa

CONCLUSION

The high density of [3H]-pranlukast binding sites on the local leukocytes in human nasal mucosa suggests that CysLT1 receptor antagonists may directly modulate cellular function of the local leukocytes through binding to CysLT1 receptor on allergic nasal mucosa.

OBJECTIVES

The cysteinyl leukotrienes (CysLTs) are lipid mediators that have been implicated in the pathogenesis of allergic diseases. Pharmacological studies using CysLTs indicate that two classes of receptors named CysLT1 and CysLT2 receptor exist. The former is sensitive to the CysLT1 receptor antagonist currently used to treat asthma and allergic rhinitis. To confirm the binding sites of CysLT1 receptor antagonist in human nasal mucosa, the autoradiographic distribution of CysLT1 receptor was studied in human nasal inferior turbinates.

MATERIALS AND METHODS

Cryostat sections were incubated with [3H]-pranlukast for autoradiography. Nonspecific binding was determined by adding unlabelled pranlukast.

RESULTS

Autoradiograms indicated [3H]-pranlukast densely labeled on the interstitial cells. Blood vessels were sparsely labeled. There was no specific labeling in the submucosal glands or epithelium. These results support our previous report from in situ hybridization and immunohistochemistry of CysLT1 receptor.

Expression and localization of TRPV1 in human nasal mucosa

Capsaicin is the pungent principle in chili peppers and previous studies reported that topical application of capsaicin to patients with allergic and non-allergic rhinitis produced significant and long-lasting relief of symptoms. The capsaicin receptor (TRPV1, VR1) is a nociceptive transducer and the existence of TRPV1 in non-neuronal cells as well as neuronal cells has been reported. In order to clarify the role of TRPV1 on the upper airway, we examined the localization and the expression of TRPV1 in human nasal mucosa. Surgically obtained human nasal specimens were processed for immunohistochemistry with commercial anti-TRPV1 antibody. We also performed immunofluorescence with anti-TRPV1 antibody and anti-neurofilament antibody or anti-CD31 antibody. Epithelial cells and vascular endothelial cells were cultured from nasal turbinates, respectively. For RT-PCR analysis, total RNA was isolated, and then RT-PCR was performed. Immunohistochemical studies revealed that TRPV1 positive cells were found on epithelial cells, vascular endothelial cells, submucosal glands and nerves in human nasal mucosa. By RT-PCR analysis, the mRNA expression of TRPV1 was confirmed in human nasal mucosa. These results suggest that capsaicin can directly influence the epithelial secretory and various functions via TRPV1 as well as the activation of the sensory neurons.

[Relationship between pollen allergy and oral allergy syndrome]

We recently evaluated the relationship between pollen allergy and oral and pharyngeal hypersensitivity to fruits and vegetables (oral allergy syndrome) over 8 years (1995 approximately 2002) in Sapporo. 1. Of 843 patients with birch pollen (BP) allergy (CAP score 2 or more), 378 patients (37%) had episodes of oral allergy syndrome (OAS), and the rate in BP allergy was higher than in other allergies. 2. In patients with BP allergy, the most frequent foods causing OAS were apple, peach and cherry, followed by kiwi, pear, plum and melon. BP allergy patients demonstrated much more OAS with these foods than the patients without BP allergy. The higher the CAP score of BP, the higher the incidence of OAS to these foods was found to be. In patients with OAS and BP allergy, the higher the CAP score of BP, the higher the number of foods causing OAS was found to be. 3. In patients with BP allergy, a multiple logistic regression analysis was performed to identify factors affecting the rate of OAS. Positive factors were a high BP CAP score and being female. A negative factor was mite CAP positive. Furthermore, mugwort pollen (MP) CAP positive patients had much more OAS to kiwi and tomato than MP CAP negative patients.

Expression and localization of platelet-activating factor receptor in human nasal mucosa

BACKGROUND

Platelet-activating factor (PAF) has been thought to be a potent mediator of allergic rhinitis because PAF was recovered from the nasal lavage fluid of patients with allergic rhinitis after allergen provocation. Furthermore, PAF receptor antagonist attenuates the antigen-induced increase in nasal airway resistance and nasal vascular permeability in sensitized guinea pigs.

OBJECTIVE

To clarify the expression of PAF receptor in human nasal mucosa by investigating PAF receptor messenger RNA (mRNA) expression and its protein localization using polymerase chain reaction (PCR) and immunohistochemical analyses, respectively.

METHODS

Human turbinates were obtained after turbinectomy from 6 patients with nasal obstruction refractory to medical therapy. Total RNA was isolated from human nasal mucosa, and PAF receptor mRNA was detected in these tissues by using reverse transcriptase-PCR analysis. To identify the cells expressing PAF receptor protein, double immunostaining was performed using anti-PAF receptor antibody and monoclonal antileukocyte antibodies.

RESULTS

Reverse transcriptase-PCR analysis of total nasal RNA demonstrated the expression of PAF receptor mRNA. The immunohistochemical studies revealed that anti-PAF receptor antibody-labeled eosinophils, macrophages, neutrophils, mast cells, lymphocytes, vascular endothelial cells, epithelial cells, and submucosal glands in nasal mucosa.

CONCLUSIONS

These results may have important clinical implications for understanding the role of PAF receptor on upper airway diseases such as allergic and nonallergic rhinitis.

Culture of cells harvested with nasal brushing: a method for evaluating ciliary function

OBJECTIVES

Usefulness and reliability of nasal brush samples in a monolayer cell culture was studied for evaluation of ciliary movement.

METHODS

Cells for cultures were harvested under the middle turbinate from patients with chronic sinusitis and from controls. Ciliary function was analysed using a microscope equipped with a high-speed video camera. Ciliary beat frequency (CBF), ciliary amplitude, waveform and coordination were analysed from the cultures 4-6 h after the harvest of brush samples and 3 days after the culture.

RESULTS

The average success rate of cell cultures was 82.5%. There were not statistically significant differences in CBF between patients and controls but there was significant difference between brush biopsy and cultured brush biopsy in controls. The ciliary beat amplitude and the waveform were normal in all samples in both groups.

CONCLUSIONS

Miniculture method for culturing nasal cells from brush biopsies proved reliable and non-invasive for detailed analysing of ciliary function and for excluding possible secondary ciliary dyskinesia. Compared to conventional mucosal cell cultures where thick and invasive specimens are needed for successful cultures, it is easier and quicker to perform and well tolerated by patients. Thin monolayer cultures enable the evaluation of frequency, amplitude and the waveform of the cilia beat under the microscope whereas floating cells and cell clusters do not give this opportunity.

Expression and localization of steroid receptors in human nasal mucosa

OBJECTIVE

To investigate the expression of glucocorticoid receptor (GR), oestrogen receptor (ER), progesterone receptor (PR) and androgen receptor (AR) in nasal mucosa.

MATERIAL AND METHODS

Human turbinates were obtained after turbinectomy from seven patients. The expression and localization of steroid receptors were examined using reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry.

RESULTS

Using RT-PCR, GR and ER alpha mRNA were detected in all cases. In contrast, ER beta, PR and AR mRNA were found in five, four and six cases, respectively. Using immunohistochemistry, antibodies to GR showed the presence of GR within all cells of nasal mucosa, with the highest quantities of GR being localized in epithelial cells, submucosal glands and inflammatory leukocytes. Immunohistochemical analysis of sex steroid receptor revealed that anti-ER alpha antibody labelled mainly mast cells and anti-ER beta antibody labelled submucosal glands, and that no PR or AR expression was detected in any of the samples tested.

CONCLUSIONS

The role of ER in mast cells and submucosal glands has not been well clarified. However, precise knowledge of the identity and distribution of sex steroid receptor should be of considerable interest in understanding the role of sex hormones in upper airway diseases such as allergic and non-allergic rhinitis.

Expression of neurokinin a receptor mRNA in human nasal mucosa

In airway tissues, it has been suggested that tachykinins act as the transmitter for afferent sensory nerves which respond to various irritants and may be involved in airway allergic reactions. Three classes of tachykinin receptor have been recognized, denoted NK1, NK2 and NK3, which exhibit preferential affinity for substance P, neurokinin A and neurokinin B, respectively. We used molecular probes to study the gene expression and distribution of NK2 receptor in human nasal mucosa. Total RNA was isolated from human nasal mucosa and NK2 receptor mRNA was detected in these tissues using reverse transcriptase polymerase chain reaction (RT-PCR). For an in situ hybridization study of human nasal mucosa, we utilized the PCR directly to incorporate a T7 RNA polymerase promoter sequence onto the NK2 receptor cDNA, and these PCR products were used as the DNA template for producing digoxigenin-labeled antisense and sense RNA probes. These studies revealed that NK2 receptor mRNA was expressed in blood vessels. The results suggest a primary role for neurokinin A in the form of vascular responses in the upper respiratory tract.

Effects of glucocorticoids on infiltrating cells and epithelial cells of nasal polyps

Glucocorticoids are known to be effective in the treatment of nasal polyps (NPs). To examine the mechanisms of their effect, we evaluated 1) the ability of glucocorticoids to induce the apoptosis of eosinophils and T lymphocytes in NPs, and 2) the ability of dexamethasone to down-regulate epithelial cell functions that relate to eosinophilic inflammation. In vitro and in vivo, glucocorticoids increased the apoptosis of both eosinophils and T lymphocytes in NPs. Dexamethasone inhibited the production of granulocyte-macrophage colony-stimulating factor (GM-CSF) from both NP epithelial cells that were unstimulated and NP epithelial cells that were stimulated with interleukin-4 or tumor necrosis factor alpha. These results suggest that the clinical efficacy of glucocorticoids on NPs may be due to 1) induction of apoptosis in both eosinophils and T lymphocytes that infiltrate NPs, and 2) down-regulation of epithelial GM-CSF production, which prolongs eosinophil survival.

[Study of thromboxane A2 antagonist reduction in the treatment of patients with perennial allergic rhinitis]

We investigated whether or not we could reduce the medication for patients with perennial allergic rhinitis after improvement of the nasal symptoms. We administered the thromboxane A2 receptor antagonist Ramatroban, which also improves non-specific hypersensitivity, for 4 weeks and then reduced the dose to half for 4 weeks and investigated the severity of general symptoms and each nasal symptom (sneeze, rhinorrhea, and congestion). There was a significant improvement in the severity of general symptoms and each nasal symptom for the first 4 weeks (p<0.01), which was maintained for 4 weeks after reduction of the dose (n=14). There was no difference in the severity of symptoms between the reduced dosage (n=14) and the maintained dosage (n=15) groups. We also investigated the level of eosinophilia in nasal smears before and after the treatment (n=14) and showed that the level was significantly (p<0.01) reduced after the start of treatment. In conclusion, it was noted that we could reduce the dose of Ramatroban after the improvement of nasal symptoms on patients with perennial allergic rhinitis.

Melanin pigmented oncocytic metaplasia of the nasopharynx

A case of melanin pigmented oncocytic metaplasia is reported. A 62-year-old man presented with a history of discomfort of the ear of a 2 weeks' duration. Nasoscopic examination revealed a black nodule of about 5mm at the left Eustachian opening, and several black spots were discovered around the bilateral torus tubarius. The nodule was biopsied to determine the histology. Microscopically, there were oncocytic cells with abundant pigmented granules showing glandular pattern. Such a pigmented variant of benign oncocytic lesion is very rare.