The‘nasal pool’device applies controlled concentrations of solutes on human nasal airway mucosa and samples its surface exudations/secretions

Abstract

A 'nasal pool' (NP) device, a compressible plastic container with an adapted nozzle, was used to perform a continuous 10-min nasal provocation and lavage. This novel technique brings known concentrations of agents into contact with a large and defined area of the nasal mucosal surface for extended periods of time. Simultaneously, the surface exudations/secretions of the same nasal mucosa are effectively sampled by the NP fluid. A concentration-response study of histamine (80, 400 and 2000 micrograms/ml) was performed in 12 normal subjects on three different occasions. Exudation of plasma albumin into the lavage fluid was measured to quantitate the histamine-induced airway inflammation. The effect of the dwell time on exudation was examined using histamine (400 micrograms/ml) instilled in the nasal cavity for time periods from 10 sec to 10 min. The time course of histamine-induced plasma exudation response was studied by exposing the mucosa to histamine (400 micrograms/ml) for 12 min, with the NP renewed every minute. Allergen-provocations were performed in subjects with hay fever and TAME-esterase activity in the returned lavage fluid was determined to indicate the degree of response. Histamine produced a concentration-dependent increase in albumin levels in the NP fluid; 123.3 +/- 25.6, 213.8 +/- 19.7 and 430.2 +/- 32.0 micrograms/ml (mean +/- s.e.m.), respectively. The time-course study demonstrated that plasma exudation into the lumen occurred promptly and that the exudation response reached a maximum after exposure to histamine for 6-10 min. The dwell-time experiments supported this finding. After 10 min the exudation appeared to decline despite the continued presence of histamine.(ABSTRACT TRUNCATED AT 250 WORDS)

Loss of size-selectivity at histamine-induced exudation of plasma proteins in atopic nasal airways

“…Thus, it is anticipated that practically all circulating plasma proteins, irrespective of size, can readily be made available to combat inflammatory insults on the surface of an intact airway mucosa. The nasal pool method used in this study has been validated previously with regard to gentleness to the airway mucosa, challenge effects, reproducibility and almost quantitative retrieval of instilled fluid into the nasal cavity (Greiff et al, 1990). It has also been used to demonstrate onset, peak and duration of the exudative action of histamine in the human nose (Greiff et al, 1990).…”

Contribution of Plasma‐Derived Molecules to Mucosal Immune Defence, Disease and Repair in the Airways

“…The luminal entry is further a most readily recruited route. It occurs without the prior build up of oedema in the mucosa and it extends down to threshold exudative stimuli [4,17,21] where, in fact, extravasation into the airway tissue may be below detection limits [17]. The lack of oedema at acute airways plasma extravasation responses was once a lead on to the in vivo discovery (not predicted by in vitro or other research paradigms) that extravasated bulk plasma readily traverses the normal epithelial lining [6].…”

Biomarkers in asthma and allergic rhinitis

“…In this method, NaCl 0.9% is instilled into the nose while the subject is closing off the nasopharynx. Another NAL technique is the so-called ''headforward'' method where a nasal pool device is used to instill saline into the nose [183]. When comparing the methods, the first has been shown to yield more reproducible ECP levels, while the latter allows a higher and more reproducible recovery of cell counts [184].…”