Nasal cytology: Methodology with application to clinical practice and research.

Nasal cytology is an easy, cheap, non-invasive and point-of-care method to assess nasal inflammation and disease-specific cellular features. By means of nasal cytology, it is possible to distinguish between different inflammatory patterns that are typically associated with specific diseases (ie, allergic and non-allergic rhinitis). Its use is particularly relevant when other clinical information, such as signs, symptoms, time-course and allergic sensitizations, is not enough to recognize which of the different rhinitis phenotypes is involved; for example, it is only by means of nasal cytology that it is possible to distinguish, among the non-allergic rhinitis, those characterized by eosinophilic (NARES), mast cellular (NARMA), mixed eosinophilic-mast cellular (NARESMA) or neutrophilic (NARNE) inflammation. Despite its clinical usefulness, cheapness, non-invasiveness and easiness, nasal cytology is still underused and this is at least partially due to the fact that, as far as now, there is not a consensus or an official recommendation on its methodological issues. We here review the scientific literature about nasal cytology, giving recommendations on how to perform and interpret nasal cytology.

Monitoring of seasonal variability in bronchial hyper-responsiveness and sputum cell counts in non-asthmatic subjects with rhinitis and effect of specific immunotherapy.

Bronchial hyper-responsiveness (BHR) is documented in a proportion of non-asthmatic individuals with allergic rhinitis (NAAR) and reflects inflammatory events in the lower airways. Natural exposure to allergens is known to modulate BHR and the level of airway inflammation in asthma, but less consistently in NAAR. Specific immunotherapy (SIT) attenuates symptoms possibly by reducing BHR and airway inflammation. The influence of natural exposure to Parietaria pollen on BHR and sputum cell counts of NAAR was investigated and the effect of Parietaria SIT examined. Thirty NAAR, monosensitized to Parietaria judaica, participated in a randomized, double-blind, placebo-controlled, parallel group study of the effects of a Parietaria pollen vaccine on symptoms/medication score, BHR to inhaled methacholine and adenosine 5'-monophosphate (AMP), and cell counts in the sputum collected out of and during the pollen seasons for 36 months. Seasonal variation in BHR to inhaled methacholine and AMP and changes in sputum cell counts were documented. Changes were consistent for AMP, but not methacholine, and invariably associated with modifications in sputum eosinophils and epithelial cells. The clinical efficacy of Parietaria SIT was associated with a decline in the seasonal deterioration of BHR to AMP, whereas no significant effect was observed on BHR to methacholine or sputum cell differentials. Between-groups comparison of the seasonal changes in PC15 methacholine values and sputum cell differentials calculated as the AUC were not statistically significant, whereas a significant difference in PC15 AMP was demonstrated throughout the study (P=0.029), the median (inter-quartile range) AUC values being 2478.5 (1153.3-3600.0) and 1545.5 (755.3-1797.9) for the SIT- and placebo-treated group, respectively. Bronchial airways of NAAR exhibit features of active inflammation that deteriorate during natural allergen exposure, particularly with regard to BHR to AMP. The clinical efficacy of Parietaria SIT was exclusively associated with attenuation in seasonal worsening of PC15 AMP, suggesting that AMP may be useful in monitoring changes in allergic inflammation of the airways.

Intranasal heparin reduces eosinophil recruitment after nasal allergen challenge in patients with allergic rhinitis.

BACKGROUND: Recently, several studies have shown that heparin possesses various anti-inflammatory and antiallergic properties. It has been proposed that heparin might play an important role in limiting the inflammatory events associated with asthma and allergic rhinitis by neutralizing inflammatory mediators, such as eosinophil cationic protein and major basic protein, and by limiting eosinophil recruitment. OBJECTIVE: To test the hypothesis that heparin can limit the extent and magnitude of eosinophilic inflammation, we examined the effect of inhaled intranasal heparin on nasal response to allergen challenge in 10 patients with allergic rhinitis. METHODS: The capacity of heparin to reduce nasal response was studied by evaluating symptom score, eosinophil cationic protein concentration, and eosinophil counts in nasal lavage fluids 10, 60, and 360 minutes after allergen challenge. RESULTS: Pretreatment with intranasal heparin produced a significant reduction in symptom score 10 minutes after allergen challenge and reduced the eosinophil influx at each time point after antigen challenge, statistical significance being reached 60 and 360 minutes after allergen challenge. Similarly, the amount of eosinophil cationic protein in the nasal wash was reduced at each time point; this reached statistical significance 360 minutes after allergic challenge. CONCLUSION: Heparin was shown to provide protection with respect to nasal allergen challenge. The mechanism by which heparin produces its protective activity seems to be related to the neutralization of eosinophil cationic protein as well as to the reduction of eosinophil recruitment.

Normal human lung fibroblasts differently modulate interleukin-10 and interleukin-12 production by monocytes: implications for an altered immune response in pulmonary chronic inflammation.

The ability of lung fibroblasts to modulate the immune response has been evaluated by analyzing the synthesis and release of interleukin (IL)-10 and IL-12 by lipopolysaccharide (LPS)-stimulated peripheral blood monocytes exposed to pulmonary fibroblast conditioned medium (FCM). IL-10 and IL-12 contents and gene expression were markedly modified by treatment with FCM as measured by ELISA (+97.5 +/- 12.8% and -68 +/- 7.3% for IL-10 and IL-12, respectively), immunocytochemistry, and reverse transcriptase-polymerase chain reaction (RT-PCR). These effects appeared to be mediated by prostaglandin E(2) (PGE(2)) as the modified release of both cytokines was reduced by treatment with indomethacin and mimicked by addition of exogenous PGE(2.) As a result of the enhanced production of IL-10, exposure of LPS/interferon (IFN)-gamma-activated monocytes to FCM was also able to reduce the expression of the class II major histocompatibility complex (MHC) molecule, human leukocyte-associated antigen-DR (HLA-DR) (-51.8 +/- 8.7%) and of the costimulatory molecule, CD40 (-53.9 +/- 11.7%). The expression of both molecules was completely restored when monocytes were pretreated with a neutralizing anti-IL-10 monoclonal antibody. The FCM obtained from fibrotic lung fibroblasts was instead less efficacious in potentiating LPS-stimulated IL-10 release and, consequently, in reducing HLA-DR and CD40 expression, suggesting that an impairment of the immune regulation operated by fibroblasts may be involved in the maintenance of chronic pulmonary inflammation.

Different expression of TNF-alpha receptors and prostaglandin E(2 )Production in normal and fibrotic lung fibroblasts: potential implications for the evolution of the inflammatory process.

Normal human lung fibroblasts downregulate the production of tumor necrosis factor (TNF)-alpha by activated monocytes through the production of prostaglandin E(2) (PGE(2)), contributing to the local control of the inflammatory process. In this study, we provide evidence that fibroblasts derived from diseased tissue, such as fibrotic lung fibroblasts, exhibit different functional features compared with normal cells, with particular regard to their modulatory role. Indeed, fibrotic fibroblasts (FF) spontaneously produced less PGE(2) (3,300 +/- 410 pg/ml) compared with normal fibroblasts (NF) (7,500 +/- 270 pg/ml) and, as a consequence, they showed a reduced ability to downregulate the production of TNF-alpha by lipopolysaccharide (LPS)- activated monocytes. The percentage of inhibition induced by normal cells on the production of TNF-alpha by LPS-activated monocytes was 61 +/- 5.9%, whereas the inhibitory effect exerted by fibrotic cells was reduced to 32 +/- 4% (P < 0.01). We have also observed that the ability of TNF-alpha to induce PGE(2) was impaired in FF and was related to a reduced expression of cyclooxygenase 2. This was possibly due to the reduction of the expression of TNF receptors (TNFRs) in fibrotic cell lines compared with normal cell lines. Flow cytometry revealed that the mean fluorescence intensity (MFI) of both isoforms of TNFR was significantly lower in FF compared with NF. The MFI of TNFR1 was 3. 55 +/- 0.12 for NF and 1.78 +/- 0.35 for FF (P < 0.001). The MFI of TNFR2 was 1.95 +/- 0.27 for NF and 0.99 +/- 0.16 for FF (P < 0.01). The analysis of the effect of TNF-alpha on some functions associated with collagen metabolism in NF and FF showed an increase of the expression of the receptor for collagen type I (alpha(2)beta(1) integrin) in NF (42 +/- 10%) and an even larger increase in FF (102 +/- 23%) (P < 0.05). Interestingly, unlike NF, TNF-alpha failed to increase matrix metalloproteinase 1 levels in FF and did not cause any growth inhibition in these cells. The reduced capability of fibrotic cells to produce PGE(2) either spontaneously or after TNF-alpha treatment may lead to an unrestrained release of TNF-alpha from activated monocytes and, as a result of the reduced expression of TNFRs, to a different response of these cells to TNF-alpha. These changes may be important in the evolution of the inflammatory process, potentially contributing to its transformation into a chronic and self-perpetuating process.

Bronchial hyperresponsiveness and airway inflammation markers in nonasthmatics with allergic rhinitis.

Bronchial hyperresponsiveness (BHR) is a characteristic feature of asthma which is often associated with airways inflammation. However, some patients with allergic rhinitis and no clinical evidence of asthma also exhibit BHR. This study therefore investigated whether inflammatory cell infiltrate is present in the induced sputum of nonasthmatic subjects with allergic rhinitis during the pollen season and examined its relationship with airway hyperresponsiveness to inhaled methacholine and adenosine 5'-monophosphate (AMP). Twenty subjects (12 allergic rhinitis, eight nonallergic controls) underwent methacholine and AMP challenge and sputum induction with hypertonic saline on separate days. Cell differentials were calculated from whole sputum samples. A significantly greater number of eosinophils was found in the sputum of nonasthmatic subjects with allergic rhinitis compared to that of nonallergic controls, their median (range) percentages being 17.5 (4-47) and 1.5 (0-5) (p<0.001) respectively. Although sputum eosinophilia failed to be significantly associated with methacholine responsiveness (r(s)=-0.50; p=0.095), the provocative concentration of AMP causing a 20% fall in forced expiratory volume in one second correlated strongly and significantly with the absolute number of eosinophils (r(s)= -0.73; p=0.007). Eosinophil cationic protein levels in the sputum of rhinitic subjects were significantly elevated compared to controls and correlated with eosinophil number (r(s)=0.67; p=0.017). These findings support the view that bronchial eosinophilia alone is insufficient to cause asthmatic symptoms. Diverse agonists for assessing bronchial hyperresponsiveness are selectively associated with airway inflammation in allergic rhinitis.

Human lung fibroblasts inhibit tumor necrosis factor-alpha production by LPS-activated monocytes.

Mononuclear phagocytes are important regulators of normal immune, inflammatory, and fibrotic responses. These functions are mediated through the production of several cytokines, including tumor necrosis factor-alpha (TNF-alpha), which regulate the activity of inflammatory and tissue structural cells such as fibroblasts. It is increasingly evident that fibroblasts are also capable of releasing a number of cytokines and soluble factors that can, in turn, interact with monocytes and thereby modulate the inflammatory process. In this study we provide evidence that human lung fibroblasts, through the release of soluble factors such as prostaglandin E2 (PGE2), inhibit both TNF messenger ribonucleic acid (mRNA) accumulation and TNF-alpha protein release by lipopolysaccharide (LPS)-activated human peripheral blood monocytes (PBM). Reverse transcriptase-polymerase chain reaction (RT-PCR) results showed that fibroblast-conditioned medium (FCM) caused a 50% reduction of the TNF-alpha transcript accumulation in LPS-stimulated monocytes. Furthermore, FCM induced a significant decrease in the release of TNF-alpha by LPS-activated PBM. This effect was dependent on the concentration of the FCM and the number of fibroblasts producing it. The maximal effect was seen with monocytes cultured in 100% FCM produced by 2 x 10(6) fibroblasts. This indicated that one or possibly more soluble factors released by fibroblasts were responsible for the effect. Considering that exogenous PGE2 can inhibit TNF-alpha production by PBM, and that fibroblasts are a good source of PGE2, we determined the content of PGE2 in the FCM used in our experiments. We found a good correlation (r = 0.949) between the amount of PGE2 produced by fibroblasts and the degree of TNF-alpha inhibition exerted. In addition, the inhibitory effect of FCM was mimicked by the addition to PBM cultures of exogenous PGE2 in amounts similar to those spontaneously released by fibroblasts in FCM. All of these data suggest a molecular and cellular interaction between PBM and fibroblasts that could contribute to those modulatory mechanisms involved in the self-limitation of the fibrotic process.

On the pollen morphology and frequency of allergic sensitization in Sicily of the genus Salsola L. (Chenopodiaceae).

The pollen morphology of the genus Salsola L. (Chenopodiaceae) and the distribution of the plant in Italy was described and the frequency of sensitization in a population of allergic patients was studied. Sensitization to Salsola was present in 13.7% of 343 allergic patients. This sensitization has always been observed in association with other pollens except for one case. The importance of this sensitization in the Mediterranean areas was emphasized considering the common frequency of Chenopodiaceae sensitization and the very frequent cross-reactivity within the same family and between Chenopodiaceae and Amaranthaceae.