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Notes: Bagnasco M, Canonica GW. Influence of H1-receptor antagonists on adhesion molecules and cellular traffic.

Notes: The protective effects of deflazacort against the inflammation that follows the conjunctival provocation test (CPT) by specific allergen were assessed in 24 patients with rhinoconjunctivitis caused by Parietaria judaica in a double-blind study. After a screening CPT, patients were randomized into four treatment groups, each being given deflazacort (oral tablets) at 6, 30, and 60 mg once daily, or matching placebo, for 3 d, outside the pollen season. Clinical evaluation (itching, hyperemia, lacrimation, and swelling of eyelids) and cytologic assessment (number of inflammatory cells in conjunctival scraping and evaluation of ICAM (intercellular adhesion molecule)-1/CD54 expression on epithelial cells) were performed at base line, 30 min (early-phase reaction (EPR), 6 h and 24 h (late-phase reaction (LPR)) after specific CPT, and before and after treatment. Neither the EPR clinical reactions nor the EPR total number of inflammatory cells was modified by deflazacort. However, the LPR clinical effects were significantly reduced by deflazacort at 30 or 60mg/d (P〈0.01), as compared with placebo. The total number of inflammatory cells during LPR was significantly reduced by deflazacort at 30 or 60 nig/d ((P〈0.01), as compared with placebo. Furthermore, CD54 expression was significantly reduced by deflazacort at 30 or 60 mg/d both in the EPR ((P〈0.01) and LPR ((P〈0.01), as compared with placebo. None of the studied indicators were modified at the 6 mg/d dose. This study shows that deflazacort has a highly protective action against clinical and cellular LPR effects induced by the specific CPT, In addition, deflazacort markedly reduces CD54 expression on the conjunctival epithelium during both EPR and LPR.

Notes: Background Local nasal immunotherapy is accepted as an alternative to the injection route for allergic rhinitis. Despite this, little is known about the kinetics of the allergen after nasal delivery in allergic subjects.Objective We aimed at assessing the biodistribution of 123I-radiolabelled Par j 1 in Parietaria-allergic subjects, in comparison with healthy volunteers.Methods Purified Par j 1 was radiolabelled with 123I and sprayed into the nostrils of three control subjects and three Parietaria-allergic volunteers. Dynamic and static scintigraphic images of the head were recorded at serial times and blood samples were obtained to measure the plasma radioactivity, and to assess the presence of circulating radiolabelled species by gel chromatography.Results In Parietaria-sensitized subjects, the radiolabelled allergen was rapidly cleared from the nasal cavity and transported to pharynx, and little local persistence was seen. This differed from healthy subjects where nasal clearance of the tracer was slower and nasal radioactivity persisted up to 24 h. The increase in plasma radioactivity paralleled swallowing of the allergen in both groups, and plasma chromatographic profile did not differ between allergic and healthy volunteers.Conclusions Sensitization to the allergen affects its local biodistribution. Gastrointestinal absorption is relevant also for the intranasal route.

Notes: Little is known about the pharmacokinetics of allergens for local immunotherapy. Thus, we studied the pharmacokinetics in allergic volunteers of a commercial allergenic vaccine in orosoluble tablets (LAIS®, Lofarma S.p.A).The carbamylated monomeric allergoid derived from Parietaria judaica major allergen (Par j 1), characterized by maintenance of the original molecular size, and the native allergen, were radiolabelled with 123I, then incorporated into the commercial soluble tablets and administered to allergic subjects. Early sequential and late static scintigraphic acquisitions were performed, and plasma radioactivity was measured at different time intervals.No difference in local pharmacokinetics was observed between the allergen and the allergoid: part of the tracer was retained in the mouth for at least 2 h after swallowing. No direct absorption through the oral mucosa could be detected, as plasma radioactivity increased only after swallowing and peaked at 2 h. However, the plasma peak attained with the allergoid in tablets was significantly higher with respect to the native allergen. Finally, some undegraded allergoid, but not the allergen, could be constantly detected in the bloodstream at plasma peak.The results showed a similar behaviour of the allergoid and the allergen in tablets as far as their local kinetics are concerned, whereas plasma peak was higher with the allergoid than with the allergen. Therefore we conclude that the chemical modification of the allergen may affect its pharmacokinetics, by making it less susceptible to enzymatic degradation.

Notes: Background The intercellular adhesion molecule ICAM-1 has been detected by immunohistochemical methods on epithelial cells of the conjunctiva and nose during allergic inflammation.Objective The aim of the present study was to evaluate whether ICAM-1 expression on conjunctival epithelium derives from endogenous synthesis or is merely due to passive uptake of soluble ICAM-1 released from inflammatory cells.Methods In situ hybridization was performed using a 3’end dygoxygenin-labelled specific DNA oligonucleotide probe on fixed conjunctival smears from allergic subjects challenged with, or naturally exposed to the allergen, and from healthy subjects. Immunocytochemistry for ICAM-1 was performed by alkaline phosphatase antialkaline phosphatase.Results Results In allergic patients, both naturally exposed to the allergen and after specific challenge, a clear hybridization pattern on epithelial cells was apparent. Out of allergen exposure, some symptomfree pollinosic subjects, as well as a few healthy volunteers showed mild ICAM-1 mRNA cytoplasmic staining in the absence of immunohistochemically detectable ICAM-1. This finding may explain the very early appearance of ICAM-1 on conjunctival epithelium following specific challenge in allergic individuals.Conclusions These results indicate that the presence of ICAM-1 on conjunctival epithelium during allergic inflammation derives from endogenous synthesis and not from uptake of soluble ICAM-l.

Notes: Background Cetirizine is an antihistamine, largely used in the treatment of allergic rhinoconjunctivitis, which also exerts anti-allergic activity.Objectives To evaluate cetirizine as treatment for children with rhinitis due to pollen allergy, and to evaluate its anti-allergic activity in such a clinical condition.Methods The study was designed as parallel groups, double-blind, placebo-controlled, randomized. Twenty allergic children were enroled and subdivided in two groups, receiving a 4 week treatment during the pollen season. The following parameters were monitored: clinical symptoms evaluated by the allergist before and after treatment and by the patients through a daily diary card, inflammatory cells count, expression of ICAM-1 on nasal epithelial cells, inflammatory mediator levels in nasal Iavage and peripheral blood before and after treatment, and pollen counts.Results This study shows that cetirizine treatment is able to reduce: clinical symptoms (P 〈 0.01), inflammatory cell infiltrate (P 〈 0.03), ICAM-1 expression on epithelial cells (P 〈 0.05), and soluble ICAM-1 (P 〈 0.05) and ECP (P 〈 0.05) in nasal lavage.Conclusion Cetirizine is able to clinically improve nasal symptoms due to pollen allergy and to reduce allergic inflammation, which is related to allergen exposure.

Notes: Background Azelastine is a selective H1-receptor antagonist, which has previously been demonstrated to be effective in the treatment of allergic rhinitis. We have recently demonstrated that nasal azelastine inhibits the clinical and intlammatory events following nasal allergen challenge. Particularly, we focused our attention on ICAM-1 expression on epithelial cells, since it is the natural ligand of LFA-1, an adhesion molecule expressed by leucocytes, including eosinophils.Objective Since azelastine ocular drops are now available, the aim of the present study was the evaluation of the anti-allergic activity in the model of allergen specific conjunctival challenge (ASCC).Methods Twenty outpatients with allergic rhinoconjunctivitis due to Parietaria Judaica (Wall Parietary) were included outside the pollen season. The study was designed as randomized, placebo-controlled, double-blind and parallel group, developed in two parts. The fonner investigated the onset of effect of a single dose of azelastine eye drops administered 20min after clinical response due to ASCC. The latter evaluated the clinical and inflammatory parameters following ASCC after 7-days treatment with azelastine. Clinical parameters (hyperaemia, itching, lacrimation and eyelid swelling) were evaluated at baseline, 5, 10, 20 and 30 min (i.e. early phase reaction-EPR) and 6h (i.e. late phase reaction-LPR) after ASCC. Cytological assessment (number of neutrophils, eosinophils. monocytes and lymphocytes) and ICAM-1 expression on conjunctival epithelial cells were evaluated at baseline, 30 min (i.e. early phase reaction-EPR) and 6h (i.e. late phase reaction-LPR) after ASCC.Results When administered 30 min after ASCC, azetastine produced a clinical effect ranging between 10 and 20 min after eye drops administration (P 〈 0.01). After 7 days of treatment, 30 min after ASCC, azelastine induced a reduction of symptom scores during EPR and LPR (P〈0.01), a reduction of inflammatory cell infiltration during both EPR (P 0.01) and LPR (P 0.01), and a reduction of ICAM-1 expression during EPR and LPR (both P 0.01). Placebo did not modify any of the studied parameters.Conclusion Azelastine eye drops exert anti-allergic activity, inducing a rapid improvement of clinical events when administered after ASCC, and reducing both sytiiptoms and cellular infiltration when administered before ASCC. Finally, azelastine down-regulates ICAM-1 expression on epithelial conjunctival cells, confirming the results obtained at nasal level.

Notes: Background Levocabastine is a selective topical H1 antagonist, effective in the treatment of seasonal allergic rhinitis and conjunctivitis.Objective We evaluated the possible effects of levocabastine eye drops on early (EPR) and late phase (LPR) inflammatory changes induced by allergen-specific conjunctival challenge (ASCC). We focused our attention on the possible effect of levocubastine on expression of the intracellular adhesion molecule-1 (ICAM-1) on epithelial cells. Such a phenomenon is likely to play an important role in allergic inflammation.Methods The study was a double-blind, placebo-controlled, randomized trial, performed in cross-over, outside the pollen season. Ten out-patients suffcring from allergic rhinoconjunctivitis due to Parietaria Judaica (wall parietary) were enrolled. Patients randomly received levocabastine eye drops (0.5 mg/mL) or placebo eyedrops, one drop in the left eye (right eye as control), 30 min before ASCC. Clinical evaluation (hyperaemia, burning-itching, lacrimation and eyelid swelling) and cytological assessment (number of neutrophils, eosinophils and lymphocytes, and ICAM-1 expression on conjunctival epithelium) were evaluated at baseline, 30min and 6h after ASCC. In parallel, we evaluated the in vitro effect of levocabastine at concentrations ranging from 2 × 10−9 M to 2 × 10−5M on ICAM-l expression and shedding by a continuously cultured differentiated epithelial cell line (WK).Results Levocabastine reduced symptom scores during EPR (15min and 30min, P 〈 0.002), inflammatory cell infiltration duritig FPR (P 〈 0.002 for neutrophils, eosinophils and lymphocytes) and ICAM-1 expression on epithelium both during EPR (P 〈 0.002) and LPR (P 〈 0.02). LPR symptom scores and inflammatory cell infiltration were only slightly modified by levocabastine treatment. In vitro levocabastine at 2 ± 10−5 M concentration was able to down-regulate basal ICAM-1 expression, although it exerted no effect on ICAM-1 expression by interferon-γ (IFNγ)-stimulated WK cells and on soluble ICAM-1 release by epithelium.Conclusion Levocabastine exerts anti-allcrgJc activity, in that it reduces in vivo inflammatory cell infiltration due to ASCC, and also adhesion molecule expression on conjunctival epithelium. The latter phenomenon may be due, at least in part, to a direct effect of levocabastine on epithelial cells.

Notes: Canonica GW, Ciprandi G, Buscaglia S, Pesce G, Bagnasco M. Adhesion molecules of allergic inflammation: recent insights into their functional roles.

Notes: Paolieri F, Battifora M, Riccio AM, Pesce G, Canonica GW, Bagnasco M. Intercellular adhesion molecule-1 on cultured human epithelial cell lines: influence of proinflammatory cytokines.The expression of intercellular adhesion molecule-1 ‘CD54 or ICAM-1’ on epithelial cells during acute or chronic inflammation may favor the interaction between epithelial cells and leukocytes expressing the natural ligands of ICAM-1, LFA-1 ‘CD11a/CD18’, and Mac-1 ‘CD11b/CD18’. We have evaluated in vitro the expression of ICAM-1 by a conjunctival ‘WK’ and an intestinal ‘1407’ human continuous epithelial cell line. Cells were cultured for 24 h in the presence or absence of IFN-γ, TNF-α, IL-1β, IL-4, IL-6, IL-8, IL-10, and TGF-Jβ1. Both epithelial cell lines showed a constitutive expression of ICAM-1. IFN-γ at 500 U/ml and TNF-α at 200 ng/ml upregulated ICAM-1 expression; IL-1β at 100 pg/ml upregulated ICAM-1 on WK cells only. Cells cultured in the presence of both IFN-γ and TNF-α exhibited a mean fluorescence intensity far greater than those cultured with IFN-γ or TNF-α alone. 1407 and WK cells were able to release soluble ICAM-1. IFN-γ and TNF-α enhanced the release of sICAM-1. IL-4, IL-6, IL-8, IL-10, and TGF-β1 did not affect either ICAM-1 expression or sICAM-1 release. In conclusion, continuously cultured human epithelial cells may express ICAM-1 on their surface and release it in culture medium. These phenomena are upregulated by proinflammatory cytokines.