Characterization of Inflammatory Responses During Intranasal Colonization with Streptococcus pneumoniae

Nasopharyngeal colonization by Streptococcus pneumoniae is a prerequisite to invasion to the lungs or bloodstream¹. This organism is capable of colonizing the mucosal surface of the nasopharynx, where it can reside, multiply and eventually overcome host defences to invade to other tissues of the host. Establishment of an infection in the normally lower respiratory tract results in pneumonia. Alternatively, the bacteria can disseminate into the bloodstream causing bacteraemia, which is associated with high mortality rates², or else lead directly to the development of pneumococcal meningitis. Understanding the kinetics of, and immune responses to, nasopharyngeal colonization is an important aspect of S. pneumoniae infection models.Our mouse model of intranasal colonization is adapted from human models³ and has been used by multiple research groups in the study of host-pathogen responses in the nasopharynx^4-7. In the first part of the model, we use a clinical isolate of S. pneumoniae to establish a self-limiting bacterial colonization that is similar to carriage events in human adults. The procedure detailed herein involves preparation of a bacterial inoculum, followed by the establishment of a colonization event through delivery of the inoculum via an intranasal route of administration. Resident macrophages are the predominant cell type in the nasopharynx during the steady state. Typically, there are few lymphocytes present in uninfected mice⁸, however mucosal colonization will lead to low- to high-grade inflammation (depending on the virulence of the bacterial species and strain) that will result in an immune response and the subsequent recruitment of host immune cells. These cells can be isolated by a lavage of the tracheal contents through the nares, and correlated to the density of colonization bacteria to better understand the kinetics of the infection.     

蛋白多肽类药物制剂的研究进展

相对于其他的给药途径,蛋白质多肽类药物的口服、经鼻、肺部给药途径更具可行性和商业价值。利用制剂学方法可提高蛋白质多肽类药物生物利用度。通过蛋白多肽类给药系统的评价,对近年来国内外此类药物在剂型、体内外稳定性及生物利用度等方面的研究进展予以综述。     

Phase I study of α-galactosylceramide-pulsed antigen presenting cells administration to the nasal submucosa in unresectable or recurrent head and neck cancer

Background Human Vα24 natural killer T (NKT) cells are activated by the specific ligand, α-galactosylceramide (α-GalCer), in a CD1d-dependent manner. Potent anti-tumor activity of activated NKT cells has been previously demonstrated. Methods We conducted a phase I study with α-GalCer-pulsed antigen presenting cells (APCs) administered in the nasal submucosa of patients with head and neck cancer, and evaluated the safety and feasibility of such a treatment. Nine patients with unresectable or recurrent head and neck cancer received two treatments 1 week apart, of 1 × 10⁸ of α-GalCer-pulsed autologous APCs into the nasal submucosa. Results During the clinical study period, no serious adverse events (Common Terminology Criteria for Adverse Events version 3.0 greater than grade 3) were observed. After the first and the second administration of α-GalCer-pulsed APCs, an increased number of NKT cells was observed in four patients and enhanced natural killer activity was detected in the peripheral blood of eight patients. Conclusion The administration of α-GalCer-pulsed APCs into the nasal submucosa was found to be safe and induce anti-tumor activity in some patients.     

功能性鼻内窥镜手术治疗鼻窦炎与鼻息肉的疗效分析

目的:探讨功能性鼻内窥镜手术治疗鼻窦炎与鼻息肉的疗效。方法:选取350例鼻窦炎与鼻息肉患者,按随机数字表法分为两组,对照组(164例)给予综合疗法,观察组(186例)给予功能性鼻内窥镜手术联合综合疗法。通过观察并记录疗效,治疗前,治疗后3个月患者体内IL-1,IL-8水平,SF-36量表评分,评价功能性鼻内窥镜手术治疗鼻窦炎与鼻息肉的疗效。结果:经手术和药物治疗,观察组有效率明显高于对照组(P0.05),治疗前,两组IL-1和IL-8水平无统计学差异(P0.05),治疗后3个月,两组IL-1和IL-8水平均明显下降,且观察组IL-1和IL-8水平低于对照组(P0.05),治疗前,两组SF-36各项评分无统计学差异,治疗后3个月,两组SF-36评分均明显增加(P0.05)。观察组在躯体疼痛和总体健康2项评分明显高于对照组(P0.05),其余6项评分相比无统计学差异(P0.05)。结论:功能性鼻内窥镜手术对鼻窦炎与鼻息肉具有较好的疗效,能显著减轻炎症反应,改善患者生活质量,值得临床推广使用。     

Targeted brain delivery of 17β-estradiol via nasally administered water soluble prodrugs

The utility of the nasal route for the systemic delivery of 17β-estradiol was studied using watersoluble prodrugs of 17β-estradiol. This delivery method was examined to determine if it will result in preferential delivery to the brain. Several alkyl prodrugs of 17β-estradiol were prepared and their physicochemical properties were determined. In vitro hydrolysis rate constants in buffer, rat plasma, and rat brain homogenate were determined by high-performance liquid chromatography. In vivo nasal experiments were carried out on rats. Levels of 17β-estradiol in plasma and cerebral spinal fluid (CSF) were determined with radioimunoassay using a gamma counter. The study revealed that the aqueous solubilities of the prodrugs were several orders of magnitude greater than 17β-estradiol with relatively fast in vitro conversion in rat plasma. Absorption was fast following nasal delivery of the prodrugs with high bioavailability. CSF 17β-estradiol concentration was higher following nasal delivery of the prodrugs compared to an equivalent intravenous dose. It was determined that water-soluble prodrugs of 17β-estradiol can be administered nasally. These prodrugs are capable of producing high levels of estradiol in the CSF and as a result may have a significant value in the treatment of Alzheimer's disease. Published: March 25, 2002.     

Occurrence,distribution and possible role of the regulatory peptide endothelin in the nasal mucosa

Nasal blood flow is finely regulated by local release of neurotransmitters, neuropeptides and other bioactive molecules acting via paracrine mechanisms. We have investigated the occurrence and distribution in human nasal mucosa of endothelin, a potent vasoconstrictor peptide, by immunocytochemistry and the effect of systemic administration of endothelin-1 on vascular perfusion of rabbit nasal mucosa by laser Doppler flowmetry. Endothelin-like immunoreactivity was demonstrated within vascular endothelial cells in both developing and mature human mucosa. Nasal epithelial cells and some connective tissue cells, presumed to be macrophages, also displayed specific immunostaining. In rabbits injected with endothelin-1, a potent and prolonged nasal vasoconstriction was observed. It is suggested that endothelin released locally may participate in the regulation of nasal blood flow via paracrine mechanisms. Since endothelin has growth-promoting actions on several cell types, it is also tentatively proposed that this regulatory peptide may play a role during development of the nose.     

Metabolic capacity of nasal tissue: interspecies comparisons of xenobiotic-metabolizing enzymes

High levels of xenobiotic-metabolizing enzymes occur in the nasal mucosa of all species studied. In certain species, including rats and rabbits, unique enzymes are present in the nasal mucosa. The function of these enzymes is not well understood, but it is thought that they play a role in protecting the lungs from toxicity of inhalants. The observation that several nasal xenobiotic-metabolizing enzymes accept odorants as substrates may indicate that these enzymes also play a role in the olfactory process. Xenobiotic-metabolizing enzymes were found in the nasal cavity around 15 years ago. Since that time, much has been learned about the nature of the enzymes and the substrates they accept. In the present review, this information is summarized with special attention to species differences in xenobiotic-metabolizing enzymes of the nasal cavity. Such differences may be important in interpreting the results of toxicity assays in animals because rodents are apparently more susceptible to nasal toxicity after exposure to inhalants than are humans.     

Depletion of urate in human nasal lavage following in vitro ozone exposure

Ozone, a strong oxidant present in summer smog, is thought to primarily react with antioxidant molecules found in the epithelial lining fluid of the respiratory tract. In humans, as much as 40% of inhaled ozone can be removed in the nasal cavity where the major extracellular antioxidant has been identified as uric acid. The present study was undertaken to examine urate/oxidant interactions in human nasal lavage fluid following in vitro exposure to ozone at concentrations relevant to the U.K. Lavage fluid was collected from 8 volunteers using a modified Foley catheter which permits prolonged contact of isotonic saline with the anterior nasal cavity. Nasal lavage samples in multiwell plates were exposed to ozone at concentrations of 50, 100 and 250 ppb. Samples were removed at intervals from 15 to 240 min following exposure and assayed for uric acid depletion. Uric acid concentrations in the nasal lavage were found to fall from 8.52 (time zero) to 3.99 μM, 0.05 and 0.07 μM after 240 min at 50, 100 and 250 ppb ozone respectively. At a non-environmentally relevant ozone concentration of 1000 ppb, uric acid was completely depleted after 60 min. Regression analysis showed a linear correlation between rate of loss of urate and ozone concentration (R² = 0.97). A novel, non-invasive technique is described to investigate antioxidant compromise and its importance in individual subjects. We conclude that uric acid in nasal lavage samples is scavenged by ozone in a dose and time dependant manner.     

Electrophysiological evaluation of Cystic Fibrosis Conductance Transmembrane Regulator (CFTR) expression in human monocytes

Background

Cystic fibrosis is caused by mutations of CFTR gene, a protein kinase A-activated anion channel, and is associated to a persistent and excessive chronic lung inflammation, suggesting functional alterations of immune cells. Leukocytes express detectable levels of CFTR but the molecule has not been fully characterized in these cells.

Methods

Freshly isolated monocytes from healthy individuals and CF patients were assessed by protein expression, single cell electrophysiological and membrane depolarization assays.

Results

We recorded chloride currents by patch clamp in healthy monocytes, after the administration of a CFTR stimulus. Currents were sensitive to a specific blocker of the CFTR channel, CFTR_inh-172 and were absent in CF monocytes. Next, we evaluated the effects of ex vivo exposure of monocytes from cystic fibrosis patients carrying the F508del mutation to a chemical corrector, Vertex-325. We found an increase in CFTR expression by confocal microscopy and a recovery of CFTR function by both patch clamp and single cell fluorescence analysis.

Conclusions

We confirm the expression of functional CFTR in human monocytes and demonstrate that blood monocytes can represent an adequate source of primary cells to assess new therapies and define diagnosis of CF.

General significance

Tests to evaluate CFTR functional abnormalities in CF disease might greatly benefit from the availability of a convenient source of primary cells. This electrophysiological study promotes the use of monocytes as a minimally invasive tool to study and monitor CFTR function in individual patients.