Beyond anti-microbial properties: The role of cathelicidin in allergic rhinitis

BACKGROUND

Cathelicidin, an anti-microbial peptide, is a component of the innate immune system. Cathelicidin has anti-microbial, anti-inflammatory and immunoregulatory functions. Knowledge about the role of the innate immune system in the pathogenesis of allergic diseases has expanded in recent years. We measured levels of the LL-37 peptide in the nasal fluids of children with allergic rhinitis (AR) and investigated the possible role of this peptide in the pathogenesis of AR.

METHODS

The study population included 46 children who were newly diagnosed with AR and not taking any medication. Thirty-three healthy control subjects were also enrolled. Nasal secretions were collected from the study and control groups using a polyurethane sponge nasal secretion collector, and nasal fluid LL-37 levels were determined using the ELISA method.

RESULTS

The levels of LL-37 in the nasal fluid of the AR patients were lower than those of the control group (median of 2.3ng/ml [minimum-maximum, 2.1-3.2] vs. 2.6ng/ml [2.1-5.4], respectively; p<0.001), and they were significantly reduced in patients with moderate/severe AR compared with those of patients with mild AR (2.2ng/ml [2.1-2.4] vs. 2.5ng/ml [2.1-3.1], respectively; p<0.001).

CONCLUSION

Our results show that children with AR have reduced nasal fluid LL-37 levels compared with healthy controls. Additionally, children with moderate/severe AR have decreased nasal fluid LL-37 levels compared with children with mild AR. These findings highlight the role of cathelicidin in the pathogenesis of AR.

Nasal fluid secretory immunoglobulin A levels in children with allergic rhinitis

OBJECTIVES

There is growing knowledge about the immunoregulatory and possibly preventative roles of immunoglobulin A (IgA) in allergic diseases. This study aimed to investigate secretory immunoglobulin A (SIgA) levels in the nasal fluid of children who were either being treated for their allergic rhinitis (AR) with intranasal mometasone furoate or were not receiving treatment.

METHODS

The study population contained 55 children with persistent AR. Group I included 27 newly diagnosed AR patients not taking any medication and group II included 28 patients treated with intranasal steroids for at least 6 months. 27 healthy control subjects were also enrolled in the study. Total symptom scores (TSS) were calculated for each patient. Nasal secretions were obtained using a new modified polyurethane sponge absorption method, and samples were analysed by ELISA.

RESULTS

The median value for nasal fluid SIgA level in each group was 127.2μg/ml (interquartile range; 67.3-149.6) in group I, 133.9μg/ml (102.1-177.8) in group II and 299.8μg/ml (144.5-414.0) in the control group. Groups I and II both had statistically significant reductions in nasal fluid SIgA levels compared to the control group (p<0.001). However, there was no statistically significant difference between groups I and II (p=0.35). A statistically significant and negative correlation also existed between TSS and nasal fluid SIgA levels in both groups I and II (p=0.006, rho=-0.512 and p=0.01, rho=-0.481, respectively).

CONCLUSIONS

SIgA levels in the nasal fluid are significantly reduced in children with AR independent of treatment and are negatively correlated with the TSS.

Analysis of street cocaine samples in nasal fluid by Raman spectroscopy

The principal objective of this work was to demonstrate the capability of Raman spectroscopy to detect small amounts of cocaine in nasal fluid, and to identify the main drug and the most widely used cutting agents. Initially, standard samples were analysed and sampling conditions were studied by comparing different swabs used for the sample collection. Once the most appropriate swab was selected, which permitted a relatively simple detection of the standard cocaine hydrochloride, qualitative analyses of real samples were carried out. Three street cocaine samples were analysed, and the presence of cutting substances was highlighted by the appearance of different bands not corresponding to the ones of the standard cocaine. To identify the substances present in each sample, the spectra of the street cocaine samples were collected and compared with a digital library created on purpose with the spectra of the most common cutting agents. In this case, correlation coefficients permitted to recognize the most important substances presumably present in the samples, and gave an estimation of the purity of the cocaine. However, when nasal fluid was present, its strong signal could overlap or interfere with the smaller signal of the cutting substances, hindering their identification.

Determination of 3,4-methylenedioxypyrovalerone (MDPV) in oral and nasal fluids by ion mobility spectrometry

A fast and sensitive methodology has been developed for the evaluation of the 3,4-methylenedioxypyrovalerone (MDPV) consumed. Based on ion mobility spectrometry (IMS), MDPV was directly determined in nasal fluids with a limit of detection (LOD) in the order of 22 ng mL(-1), which corresponds to an absolute amount of 33 ng of MDPV per swab. MDPV was also determined after liquid-liquid microextraction (LLME) in oral fluids to avoid matrix effects, obtaining a LOD value of 4.4 ng mL(-1) in oral fluid samples. The IMS spectrum for MDPV exhibited a peak with K0 = 1.210 ± 0.005 cm(2)V(-1) s(-1) at a drift time of 14.62 ms, the total analysis time being 4.5 min per oral fluid and 1.5 min per nasal fluid sample. Samples must be analyzed within 24 h following collection and dissolution in 2-propanol, based on the complementary stability studies.