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Objective: Phosphorylcholine (PC) is a structural component of Streptococcus pneumoniae (Spn) and nontypeable Haemophilus influenzae (NTHi), and is known to be associated with adherence through the platelet activating factor receptor (PAF-R). Furthermore, high PC expression is considered to be involved in Spn and NTHi virulence. In this study, we examined the influence of PC expression on the adherence of Spn and NTHi to epithelial cells in order to clarify the potential effectiveness of a vaccine targeting PC., Methods: Twenty-seven strains of Spn and twenty-two strains of NTHi were used, cultured overnight, and PC expression was evaluated by fluorescence activated cell sorting; the strains were divided into two groups: PC low expression (PC-low) and PC high expression (PC-high) groups. Bacterial adherence was then examined using Detroit 562 cells and BALB/c mice. Bacterial invasion was then examined in Detroit 562 cells., Results: The adherence of Spn and NTHi and invasion of NTHi in the PC-high group was significantly reduced by pretreatment with a monoclonal anti-PC antibody (TEPC-15), PAF-R antagonist (ABT-491), and PC-keyhole limpet hemocyanin (PC-KLH). However, such findings were not observed in the PC-low group., Conclusion: The present study suggests that PC is involved in the mucosal adhesion of Spn and NTHi, and the mucosal invasion of NTHi with PC-high strains, but not PC-low strains. These results suggest that a PC-targeting mucosal vaccine only affects PC-high Spn and NTHi strains and does not disturb commensal bacterial flora in the upper respiratory tract, which comprises nonpathogenic PC-low bacteria., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: To better understand the causes of the exacerbation of rhinitis medicamentosa (RM) induced by oxymetazoline (OMZ) or benzalkonium chloride (BKC), we examined the impact of pretreatment with OMZ or BKC on cultured human nasal epithelial cells. We also examined the effect of mometasone furoate (MF) on the cultured human nasal epithelial cells treated with OMZ or BKC., Methods: Cells of the human nasal epithelial cell line HNEpC were treated with OMZ or BKC, and the OMZ- and BKC-induced expression of histamine H1 receptor (H1R) mRNA was assayed using real-time polymerase chain reaction. In some experiments, 1.0×10(-5)M MF was added to the HNEpC cells for 24h before treatment with OMZ or BKC., Results: Treatment with OMZ slightly increased the expression level of H1R mRNA in HNEpC cells. This enhanced expression was not significantly reduced by pretreatment with MF. In contrast, treatment with BKC remarkably increased the expression level of H1R mRNA in HNEpC cells. In addition, this enhanced expression was significantly reduced by pretreatment with MF., Conclusion: These results suggest that the increased expression of H1R mRNA due to treatment with OMZ or BKC might be one of the factors underlying the exacerbation of symptoms in patients with RM and those complicated with allergic rhinitis. The concomitant use of a nasal steroid might reduce the exacerbation of symptoms caused by BKC, although there remains a risk of developing histamine hypersensitivity from the long-term use of a topical steroid-containing BKC., (Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.)

Objectives/hypothesis: One of the major functions of vascular endothelial growth factor (VEGF) is increasing vascular permeability. We previously reported that VEGF is present in nasal secretions in rhinosinusitis, particularly in allergic rhinitis, and is hyperproduced immediately after antigen provocation. However, its function in nasal mucosa has not yet been investigated. This study was designed to estimate the increased vascular permeability by VEGF in nasal mucosa and to discuss its possible role in allergic rhinitis., Study Design: Prospective animal experiment., Methods: Hartley guinea pigs were used. Ethyl carbamate was injected into the abdomen for anesthesia, followed by intravenous injection of Evans blue into the femoral vein. Phosphate buffered saline, histamine, or VEGF was then applied to nasal cavities. Nasal mucosa was harvested after saline reflux from heart with phlebotomy by amputating the abdominal aorta. Tissue samples were soaked in formamide for 12 hours at 63 degrees C to extract dye exudates from nasal mucosa. To analyze vascular permeability, dye was quantified by colorimetry., Results: VEGF increased vascular permeability in nasal mucosa, and was more than 1 x 10(6) times more potent than histamine on the basis of molar units. Although increased vascular permeability by VEGF was not inhibited by histamine 1 receptor antagonist, it was markedly inhibited by anti-VEGF receptor antibodies., Conclusions: VEGF increased vascular permeability to a greater degree than histamine in nasal mucosa via a different pathway. Regulating VEGF may be a new therapeutic option for persistent nasal symptoms in allergic rhinitis.

We explore cellular and molecular mechanisms of nasal adjuvant of a combination of a plasmid encoding the Flt3 ligand cDNA (pFL) and CpG oligodeoxynucleotides (CpG ODN). The double DNA adjuvant given with OVA maintained prolonged OVA-specific secretory IgA (S-IgA) Ab responses in external secretions for more than 25 weeks after the final immunization. Further, both Th1- and Th2-type cytokine responses were induced by this combined adjuvant regimen. The frequencies of plasmacytoid DCs (pDCs) and CD8(+) DCs were significantly increased in nasopharyngeal-associated lymphoreticular tissue (NALT) of mice given the combined adjuvant. Importantly, when we examined adjuvanticity of pFL plus CpG ODN in 2-year-old mice, significant levels of mucosal IgA Ab responses were also induced. These results demonstrate that nasal delivery of a combined DNA adjuvant offers an attractive possibility for the development of an effective mucosal vaccine for the elderly.

Background: Vascular endothelial growth factor (VEGF), a pleiotropic polypeptide that mediates endothelial cell-specific responses such as induction of angiogenesis and vascular leakage, is hyperproduced in a variety of inflammatory disorders. In asthma, VEGF hyperproduction promotes mucosal edema by enhancing vascular leakage. However, in allergic rhinitis, details of the pathophysiological importance remain unclear. This study was designed to investigate and discuss the pathophysiological significance of VEGF in nasal secretions from perennial allergic rhinitis sufferers., Methods: Seven allergic rhinitis patients sensitized with house-dust mites and 12 chronic rhinosinusitis patients were enrolled. Nasal secretion VEGF was quantified and compared between groups. In allergic rhinitis cases, nasal lavage VEGF was estimated before and after the antigen provocation. Nasal gland VEGF was immunohistochemically investigated. VEGF messenger RNA (mRNA) levels in serous and mucous acini were analyzed by laser microdissection and light cycler-polymerase chain reaction., Results: VEGF levels in nasal secretions and nasal lavage from allergic rhinitis were higher than in nonallergic rhinosinusitis, after rather than before antigen provocation. VEGF mRNA expression was higher in serous versus mucous acini. These results are consistent with the immunohistochemistry results., Conclusion: In allergic rhinitis, there was significant VEGF production in serous acini, which was hypersecreted after antigen provocation. VEGF may play an important role in pathophysiology of allergic rhinitis.

To assess the efficacy, safety, and tissue penetration of solithromycin for the treatment of otorhinolaryngological infections, we conducted three studies: a tissue penetration study with patients scheduled to undergo otorhinolaryngological tissue removal, an open-label study comprising patients with otitis media, pharyngitis, laryngitis, and tonsillitis, and a non-inferiority study compared with high-dose cefcapene-pivoxil (CFPN-PI). Tissue penetration study; 17 patients with chronic rhinosinusitis, chronic otitis media, chronic tonsillitis, or palatine tonsillar hypertrophy, who required resection or removal of their tissue, were enrolled. Solithromycin was administered orally, and otorhinolaryngological tissues were collected 3.5–6 h after drug administration; blood was collected within 15 min before and after drug administration. The collected tissues and blood concentrations were measured at a central laboratory. Open-label study; 55 patients who were diagnosed with acute otitis media, laryngopharyngitis, or tonsillitis were enrolled. Solithromycin was administered orally 800 mg on Day 1, while on days 2–7, 400 mg of the drug was administered once daily. The primary endpoint is the clinical response at Test-of-Cure (TOC: 5–10 days after completion) Non-inferiority study; 283 patients with acute rhinosinusitis or acute exacerbation of chronic rhinosinusitis were randomized into either the solithromycin group or CFPN-PI group. Solithromycin was administered 800 mg once daily on Day 1 and 400 mg once daily while on Days 2–7 in solithromycin group, and CFPN-PI was administered 150 mg three times a day while on Days 1–7 in CFPN-PI group. The primary endpoint is the clinical response at TOC. In the tissue penetration study, the tissue concentration ratios (tissue concentration/plasma concentration) of solithromycin were 4.19 in the sinonasal mucosa, 1.33 in the middle ear mucosa, and 6.12 in the palatine tonsil tissue. In the open-label study, the efficacy rates at the TOC were 97.0 % for acute otitis media, 100 % for laryngopharyngitis, and 81.8 % for tonsillitis. In the non-inferiority study comprising patients with rhinosinusitis, the efficacy rate at the TOC was 87.7 % for solithromycin and 89.7 % for CFPN-PI. The difference in the efficacy rate (95 % confidence interval) was -2.0 % (-9.4 % to 5.4 %), verifying the non-inferiority of solithromycin to CFPN-PI. The most common adverse events in patients administered solithromycin were diarrhea (20.7 %), nausea and nasopharyngitis (3.6 %,), pharyngitis and elevated hepatic function test results (3.1 %), and abnormal hepatic function (2.1 %). Based on the findings, it is suggested that solithromycin is useful for the treatment of otorhinolaryngological infections. [ABSTRACT FROM AUTHOR]

Recent studies have demonstrated that antigen-specific IgA immune responses in nasal cavity are induced by intranasal immunization with several antigens. However, the precise mechanisms regulating such immune responses are unclear. In the present study, mice were immunized intranasally with horseradish peroxidase (HRP) plus cholera toxin into the right nostril, and HRP-specific IgA immune responses were investigated. After the immunization, an enzyme-linked im munospot assay showed an increased number of anti-HRP IgA cells in the nasal mucosa. Histochemical staining demonstrated the presence of anti-HRP antibody-secreting cells, mainly in the nasal subepithelial layer. Interestingly, these cells were induced predominantly on the right nostril, where intranasal immunization was performed. These findings suggest that antigen-specific IgA antibodies in the nasal secretions were produced locally from antibody-secreting cells in the nasal mucosa and that IgA immune responses in the nose were compartmentalized. Furthermore, lectin histochemistry showed an accumulation of peanut agglutinin-positive cells in the nasal-associated lymphoreticular tissue, suggesting the development of germinal centers in the immunized animals. [ABSTRACT FROM AUTHOR]

• Effects of PCV13 vaccination and intranasal (IN) immunization were assessed in mice. • PCV13 followed by phosphorylcholine boosted immune response against S. pneumoniae. • IN can achieve protection against S. pneumoniae serotypes not contained in PCV13. This study aimed to investigate whether systemic immunization with a 13-valent pneumococcal conjugate vaccine (PCV13) followed by intranasal (IN) immunization with phosphorylcholine (PC) can boost immune response against Streptococcus pneumoniae. Two weeks after the intraperitoneal (IP) injection of PCV13, mice were divided into two groups (mice requiring another IP injection of PCV13 and mice requiring PC-keyhole limpet hemocyanin IN immunization in combination with cholera toxin as a mucosal adjuvant) to compare the magnitude of systemic and mucosal immune responses against S. pneumoniae and PC. Serum immunoglobulin (Ig) G antibody titer against the vaccine strains of S. pneumoniae was similar between the PCV13 systemic immunization group and PC IN immunization group, while the serum IgG antibody titer against PC was significantly higher in the PC IN immunization group. PC-specific IgA antibody titer in the nasal lavage and PC-specific IgA-producing cell number in the nasal mucosa were also significantly higher in the PC IN immunization group. Induction of PC-specific IgA in the PC IN immunization group enhanced the clearance of bacteria from the middle ear. Additional IN immunization with PC after PCV13 immunization, which is currently conducted under a periodic vaccination program, can produce a booster effect comparable to that achieved by additional systemic immunization as well as PC-specific mucosal immune response, thereby providing protection against S. pneumoniae serotypes not contained in PCV13. [ABSTRACT FROM AUTHOR]