Diagnostic tools in Rhinology EAACI position paper

This EAACI Task Force document aims at providing the readers with a comprehensive and complete overview of the currently available tools for diagnosis of nasal and sino-nasal disease. We have tried to logically order the different important issues related to history taking, clinical examination and additional investigative tools for evaluation of the severity of sinonasal disease into a consensus document. A panel of European experts in the field of Rhinology has contributed to this consensus document on Diagnostic Tools in Rhinology

Intravenous versus subcutaneous injections of apomorphine in rabbits: a pharmacokinetic paradox

The objective of this investigation was an attempt to conclusively prove the accidental observation that the AUC of apomorphine in rabbits was repeatedly lower after intravenous injection compared to subcutaneous injection. Apomorphine was administered to rabbits by intravenous and subcutaneous routes at 2 different doses (0.31 mg/kg, n=10; and 0.25 mg/kg, n=6). Plasma drug concentrations were measured by HPLC-ECD and pharmacokinetic parameters were estimated by compartmental and non-compartmental approaches. The AUC of apomorphine in rabbits were: for subcutaneous injection, 14138 +/- 502 ng/ml/min and 12680 +/- 855 ng/ml/min, n=10 and 6, respectively; for intravenous injection, 11850 +/- 718 ng/ml/min and 9147 +/- 671 ng/ml/min, n=10 and 6, respectively. These AUC values were statistically significantly lower when given as intravenous injection compared to subcutaneous injection (p=0.0011 and 0.0117, n=10 and 6, respectively). The T1/2,elim values were: for subcutaneous injection, 17.1 +/- 1.70 min and 18.7 +/- 1.68 min, n=10 and 6, respectively; for intravenous injection, 15.3 +/- 1.20 min and 15.0 +/- 2.24 min, n=10 and 6, respectively. There were no significant differences between the T1/2,elim from both administration routes (p=0.3984 and 0.2158, n=10 and 6, respectively). Given the reproducibility of the results, it was concluded that the AUC of apomorphine after intravenous injection in rabbits is anomalously lower than that of subcutaneous injection.status: publishe

The lung as a route for systemic delivery of therapeutic proteins and peptides

The large surface area, good vascularization, immense capacity for solute exchange and ultra-thinness of the alveolar epithelium are unique features of the lung that can facilitate systemic delivery via pulmonary administration of peptides and proteins. Physical and biochemical barriers, lack of optimal dosage forms and delivery devices limit the systemic delivery of biotherapeutic agents by inhalation. Current efforts to overcome these difficulties in order to deliver metabolic hormones (insulin, calcitonin, thyroid-stimulating hormone [TSH], follicle-stimulating hormone [FSH] and growth hormones) systemically, to induce systemic responses (immunoglobulins, cyclosporin A [CsA], recombinant-methionyl human granulocyte colony-stimulating factor [r-huG-CSF], pancreatic islet autoantigen) and to modulate other biological processes via the lung are reviewed. Safety aspects of pulmonary peptide and protein administration are also discussed.status: publishe

In-vitro nasal drug delivery studies: comparison of derivatised, fibrillar and polymerised collagen matrix-based human nasal primary culture systems for nasal drug delivery studies

The aim of this study was to establish a collagen matrix-based nasal primary culture system for drug delivery studies. Nasal epithelial cells were cultured on derivatised (Cellagen membrane CD-24), polymerised (Vitrogen gel) and fibrillar (Vitrogen film) collagen substrata. Cell morphology was assessed by microscopy. The cells were further characterised by measurement of ciliary beat frequency (CBF), transepithelial resistance (TER), permeation of sodium fluorescein, mitochondrial dehydrogenase (MDH) activity and lactate dehydrogenase (LDH) release upon cell exposure to sodium tauro-24, 25 dihydrofusidate (STDHF). Among the three collagen substrata investigated, the best epithelial differentiated phenotype (monolayer with columnar/cuboidal morphology) occurred in cells grown on Cellagen membrane CD-24 between day 4 and day 11. Cell culture reproducibility was better with Cellagen membrane CD-24 (90%) in comparison with Vitrogen gel (70%) and Vitrogen film (< 10%). TER was higher in cells grown on Vitrogen gel than on Cellagen membrane CD-24 and Vitrogen film. The apparent permeability coefficient (Papp x 10(-7)cm s(-1)) of sodium fluorescein in these conditions was 0.45+/-0.08 (Vitrogen gel) and 1.91+/-0.00 (Cellagen membrane CD-24). Except for LDH release, CBF and cell viability were comparable for all the substrata. Based on MDH activity, LDH release, CBF, TER and permeation studies, Cellagen membrane CD-24- and Vitrogen gel-based cells were concluded to be functionally suitable for in-vitro nasal drug studies. Vitrogen film-based cultures may be limited to metabolism and cilio-toxicity studies.status: publishe

Nasal toxicological investigations of Carbopol 971P formulation of apomorphine: effects on ciliary beat frequency of human nasal primary cell culture and in vivo on rabbit nasal mucosa

OBJECTIVE: The objective of this study was to investigate the nasal toxicity of a mucoadhesive Carbopol 971P formulation of apomorphine. MATERIALS AND METHODS: The effects of different concentrations of Carbopol 971P and apomorphine on ciliary beat frequency (CBF) were studied in suspension cultures of human nasal epithelial cells. The rabbit nasal mucosal tolerance of the formulation and its components were investigated using light microscopy. Different groups of the rabbits received twice daily, air puffs, glucose, glucose/apomorphine, Carbopol 971P or Carbopol 971P/apomorphine for 1 week (glucose-treated rabbits) or 1, 2 and 4 weeks (other treatments). RESULTS: Both Carbopol 971P and apomorphine showed both concentration- and time-dependent inhibitory effects on the CBF. The effects on CBF were: apomorphine, 1.0% w/v, irreversible ciliostasis; 0.1 and 0.5% w/v, reversible cilio-inhibition; 0.01%w/v, irreversible cilio-stimulation; and Carbopol 971P, 0.1 and 0.25% w/v, partially-reversible cilio-inhibition. Glucose and glucose/apomorphine physical mixture caused mild inflammation. Carbopol 971P (both with and without apomorphine) caused severe inflammation, which increased with duration of treatment. Necrosis, squamous metaplasia or ciliary degeneration was not observed. CONCLUSIONS: Due to the severe inflammation caused by Carbopol 971P with and without apomorphine, we conclude that this polymer is not a suitable carrier for intranasal administration of apomorphine. This is in spite of the reversible effects of Carbopol 971P (0.1 and 0. 25% w/v) and apomorphine (0.1 and 0.5% w/v) on CBF.status: publishe

Effects of pharmaceutical compounds on ciliary beating in human nasal epithelial cells: a comparative study of cell culture models

PURPOSE: To test two in vitro human nasal epithelial cell culture systems for their ability to screen the effects of pharmaceutical compounds on ciliary beating. METHODS: Human nasal epithelial cells were cultured as monolayer and in a sequential monolayer-suspension culture with in vitro ciliogenesis. The influence of reference cilio-stimulatory compounds (glycocholate, isoprenaline), reference cilio-inhibitory compounds (chlorocresol, diphenhydramine) and pH on ciliary beating was investigated using computerized microscope photometry. RESULTS: Sodium glycocholate (0.5% w/v) maximally and reversibly increased CBF of the cells in both culture systems by 26 +/- 4% (monolayer) and 18 +/- 6% (suspension). Similarly, isoprenaline (10(-3) M) maximally, but irreversibly increased CBF of the cells by 14 +/-3% (monolayer) and 17 +/- 4% (suspension). Chlorocresol (0.005% w/ v) reversibly reduced the CBF of the cells by 50 +/- 6% (monolayer) and 34 +/- 4% (suspension); at a higher concentration (0.1% w/v) it resulted in instantaneous and irreversible ciliostasis. Diphenhydramine (0.1% w/v) reversibly reduced CBF in both culture systems by 45 +/- 13% (monolayer) and 69 +/- 5% (suspension); irreversible cilio-stasis occurred in less than 2 minutes in both culture systems upon cell exposure to diphenhydramine (1.0% w/v). In the monolayer culture system, CBF was stable only within the physiological pH range of 6.5-8.0; ciliary beating in the suspension culture remained stable within a pH range of 4.0-10.0. CONCLUSIONS: Both cell culture systems are suitable for screening the effects of pharmaceutical compounds on ciliary beating. Especially the sequential monolayer-suspension culture appears to be very promising as ciliary activity can be preserved for as long as 6 months.status: publishe

Safety assessment of selected cyclodextrins - effect on ciliary activity using a human cell suspension culture model exhibiting in vitro ciliogenesis

The objective of this study was to assess the cilio-inhibitory effect of a series of cyclodextrins using a human cell suspension culture system exhibiting in vitro ciliogenesis. Enzymatically released human nasal epithelial cells were cultured as sequential monolayer-suspension culture showing in vitro ciliogenesis. Ciliary beat frequency (CBF) was determined by computerized microscope photometry. Among the cyclodextrins investigated (gamma-cyclodextrin, hydroxypropyl-beta-cyclodextrin, anionic-beta-cyclodextrin polymer, dimethyl-beta-cyclodextrin and alpha-cyclodextrin), it was shown that after 30 min of exposure, gamma-cyclodextrin (10% w/v), hydroxypropyl-beta-cyclodextrin (10.0% w/v) and anionic-beta-CD polymer (8.0% w/v) were not significantly cilio-inhibitory (P > 0.05). Similarly, CBF remained stable upon cell exposure to alpha-cyclodextrin (2.0% w/v) and dimethyl-P-cyclodextrin (1.0% w/v). However, higher concentrations of alpha-cyclodextrin and dimethyl-beta-cyclodextrin resulted in mild to severe cilio-inhibition after 45 min of exposure. The effect of alpha-cyclodextrin (5.0% w/v; 54 +/- 4% cilio-inhibition) was partially reversible while dimethyl-beta-cyclodextrin (10% w/v; 36 +/- 4% cilio-inhibition) was irreversible. The cilio-inhibition observed in this model was lower than reported for chicken trachea model. Given the fact that (1) irreversible cilio-inhibition observed in this study occurred only at concentrations exceeding those used in pharmaceutical formulations and/or at an unusual exposure time (45 min) and that (2) in an in vivo situation, dilution and mucociliary clearance contribute to further decrease in local concentrations of the applied compound, the results of this study confirm the safety of the cyclodextrins investigated as nasal absorption enhancers. (C) 2000 Published by Elsevier Science B.V. All rights reserved.status: publishe