Quantification of cytokines and inflammatory mediators in samples of nasopharyngeal secretions with unknown dilution

Role of Nasopharyngeal lactate dehydrogenase as a possible economical mass screening test for the detection and segregation of SARS-CoV-2 (COVID-19) cases in India

COVID-19 pandemic is affecting almost every country in the world. Every country must test all the individuals with suspected clinical presentation of COVID-19. Unfortunately, the symptoms are mild and often the incubation period is 5–7 days. Hence, the detection of COVID-19 takes time and is costly even, many resource-constrained nations are not testing their citizens due to cost incurred. That is why we need an economical mass screening test to detect and help the health-care system to segregate cases needing their attention. Nasopharyngeal lactate dehydrogenase (LDH) is raised in viral upper respiratory infections, it can be easily tested and raised serum LDH in addition to nasopharyngeal LDH can predict stormy outcome of disease. Such prediction will help health-care system for effective resource allocation.

Increased epidermal growth factor in nasopharyngeal aspirates from infants with recurrent wheeze

Airway remodeling is known to be a consequence of repeated injury and thought to be involved in early stage of asthma. We aimed to investigate the mediators associated with airway remodeling in recurrent early wheezers. Thirty-three infants, aged 2 years or less, admitted with exacerbation of wheezing were enrolled. All of them had experienced three or more episodes of wheezing before admission. They were categorized into two groups: those who had been hospitalized two or more times for severe wheezing (N = 19) and those who had only once or never been hospitalized (N = 14). Epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), and transforming growth factor (TGF)-β1 levels in nasopharyngeal aspirates (NPA) collected on admission were measured. The difference between two patients groups divided based on their hospitalization history was assessed. We also examined these mediators in older asthmatic children (N = 15) admitted with exacerbation and their relationship with lung function parameters measured after stabilization. NPA EGF levels were significantly increased in recurrent early wheezers compared to controls. EGF, VEGF, and TGF-β1 levels were significantly higher in those with a previous history of multiple hospitalizations than in those without. In older asthmatic children, EGF levels were related with age and duration of asthma, but showed an inverse correlation with forced expiratory volume in 1 sec and forced expiratory flow between 25% and 75% of vital capacity. Our study shows that there might be significant damage during exacerbation in wheezy infants as levels of the mediators, EGF, VEGF, and TGF-β1 were higher in those who had been frequently hospitalized. It seems to suggest that those infants with severe recurrent wheezing might have chronic airway obstruction.

Sampling variability between two mid-turbinate swabs of the same patient has implications for influenza viral load monitoring

Background

With the clinical development of several antiviral intervention strategies for influenza, it becomes crucial to explore viral load shedding in the nasal cavity as a biomarker for treatment success, but also to explore sampling strategies for sensible and reliable virus collection.

Findings

In this study, 244 patients suffering from Influenza like Illness and/or acute respiratory tract infection were enrolled. Sampling was done using mid-turbinate flocked swabs and two swabs per patient were collected (one swab per nostril). The influenza A viral loads of two mid-turbinate flocked swabs (one for each nostril) per patient were compared and we have also assessed whether normalization for human cellular DNA in the swabs could be useful. The Influenza mid-turbinate nasal swab testing resulted in considerable sampling variability that could not be normalized against co-isolated human cellular DNA.

Conclusions

Influenza viral load monitoring in nasal swabs could be very valuable as virological endpoints in clinical trials to monitor treatment efficacy, in analogy to HIV, HBV & HCV viral load monitoring. However, the differences between left and right nostrils, as observed in this study, highlight the importance of proper sampling and the need for standardized sampling procedures.

Intersession repeatability of a novel nasal lavage technique

This study describes a novel nasal lavage method using a pediatric tracheostomy tube and examines intersession repeatability for several clinically and technically relevant parameters. Fourteen healthy subjects were included in this study. Both nasal cavities were washed using a standard amount of saline solution (7 mL) via a pediatric tracheostomy tube, and the 2 samples were pooled for measurement of cytokine concentrations and cell count. Recovery volume was also recorded. For each subject, measurements were repeated on 5 consecutive days. Intersession repeatability of recovery volume, cell count, and cytokine concentrations interleukin (IL)-6 and IL-8 were expressed in terms of mean coefficient of variation, intraclass correlation coefficient, and interitem correlations. Intraclass correlation coefficients and interitem correlation coefficients indicated almost perfect agreement for cell count and IL-8 concentrations. Recovery volume and IL-6 concentrations were more variable. The mean coefficient of variation was low for cell count (2%), IL-8 concentration (3%), and recovery volume (3%), whereas the mean percentage recovery was high (87%). This newly developed nasal lavage technique is repeatable over successive sessions for cytokine concentrations and cell counts in nasal secretions of healthy subjects. This method might be valuable in the study of inflammatory conditions involving the upper respiratory tract.

Ureia como marcador de diluição em amostras de lavado traqueobrônquico de potros com rodococose

No estudo das infecções e dos mecanismos inflamatórios do trato respiratório posterior, a diluição desconhecida de amostras de lavados traqueobrônquicos leva a um grave problema na interpretação das concentrações de várias substâncias. Foi investigada a amplitude da diluição em uma situação clínica verdadeira, com o objetivo de determinar a validez do uso da dosagem da ureia em lavados traqueobrônquicos para correção da diluição. As amostras do estudo consistiram em lavados traqueobrônquicos obtidos de sete potros com infecção por Rhodococcus equi. Foi realizada a contagem celular total e diferencial e comprado com o quadro clínico e a recuperação bacteriana de todas as amostras. Os fatores de diluição dos lavados variaram entre 14,3 e 130 (média 59,7). O uso da ureia como marcador de diluição melhorou a exatidão na determinação da concentração total de células nos lavados. Estes resultados sugerem que a prática de mensurar substâncias em lavado traqueobrônquico sem correção da diluição possa induzir a falsas conclusões.

The effect of topical amphotericin B on inflammatory markers in patients with chronic rhinosinusitis: a multicenter randomized controlled study

BACKGROUND

It has been suggested that an exaggerated immune response to fungi is crucial in the pathogenesis of chronic rhinosinusitis (CRS). Based on this rationale, the use of topical antifungals (amphotericin B) has been advocated. Studies on its clinical effectiveness are, however, contradictory.

OBJECTIVES

To examine the effect of nasal antifungal treatment on secreted mediators in samples of nasal lavage fluid from patients with CRS with or without nasal polyps (NP).

METHODS

Part two of a prospective double-blind, placebo-controlled multicenter clinical trial investigating the effect of 13 weeks of treatment with amphotericin B or placebo on the levels of pro-inflammatory cytokines, chemokines and growth factors (i.e., IL-1beta, IL-1RA, IL-2, IL-2R, IL-3, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 (p40/p70 subunits), IL-13, IL-15, IL-17, TNF-alpha, IFN-alpha, IFN-gamma, G-CSF, GM-CSF, MIP-1alpha, MIP-1beta, IP-10, MIG, eotaxin, RANTES, MCP-1, MCP-2, MCP-3, VEGF, EGF, FGF-basic, HGF, Gro-alpha) and albumin via a fluorescent enzyme immunoassay in nasal lavage specimens of CRS patients with or without NP.

RESULTS

Topical amphotericin B had no significant effect on the level of any of the tested pro-inflammatory cytokines, chemokines, and growth factors in CRS nasal lavage samples. Treatment with placebo, however, increased the level of MIP-1alpha and MIP-1beta, which are mediators involved in wound healing.

CONCLUSIONS

Topical amphotericin B has no significant effect on activation markers of nasal inflammatory cells in chronic rhinosinusitis with or without nasal polyps.

Evaluation of nasal IgA secretion in normal subjects by nasal spray and aspiration

OBJECTIVE

Nasal washing (NW) is a popular method for collecting human nasal lavage fluid. However, for NW the subject must be trained, and the method is unsuitable for field studies on untrained subjects. To overcome this problem, we have developed an easy and painless method, a nasal spray and aspiration (NSA) method.

METHODS

This method is different from NW in that the nasal cavity is misted over with saline, and the nasal lavage fluid is aspirated from the nostrils through a silicon tube. First, nasal lavage fluid was obtained twice by NSA with an interval of a week between lavages to evaluate intraindividual variability, and the IgA and protein levels in the nasal lavage fluid were measured by enzyme-linked immunosorbent assay and bicinchoninic acid assay, respectively. Next, the IgA value determined by NSA was compared with that by NW in another 12 normal subjects 2 days after NSA.

RESULTS

In 10 normal subjects, mean volume of saline sprayed into the nose was 0.46+/-0.15 ml (mean+/-S.D.). Mean volume of aspirated nasal lavage fluid containing both sprayed saline and nasal secretion was 0.44+/-0.37 ml. The mean IgA level/mg protein in the nasal lavage fluid determined by NSA was 112+/-18 microg/mg protein at the first and 99+/-20 at the second times of measurement, being highly reproducible. The mean value by NSA was 114+/-19 microg/mg protein, being almost the same as that by NW of 99+/-27.

CONCLUSION

These findings suggest that the IgA level/mg protein in nasal lavage fluid determined by NSA instead of NW might be useful for assessing the variability of nasal IgA secretion.

Ascorbic acid in nasal and tracheobronchial airway lining fluids

Ascorbic acid (AA) is thought to be an important antioxidant in the respiratory tract, whose regulation is yet to be fully characterized. We investigated whether AA in respiratory tract lining fluids (RTLFs) can be augmented by oral supplementation with AA. Plasma, nasal lavage fluids (NLFs), induced sputum (IS), and saliva were analyzed for AA immediately before and 2 h after ingestion of 2 g of AA in 13 healthy subjects. Concentrations of AA (median and range) were 52.5 (16.0-88.5), 2.4 (0.18-4.66), 2.4 (0.18-6.00), and 0.55 (0.18-18.90) micromol/l, respectively. Two hours after ingestion of AA, plasma AA increased 2-fold (p = .004), NLF AA increased 3-fold (p = .039), but IS and saliva AA did not increase. As AA concentrations in saliva and tracheobronchial secretions were low compared with other common extracellular components (such as urate), we evaluated the fate of AA in these fluids. Addition of AA to freshly obtained saliva or IS resulted in rapid depletion, which could be largely prevented or reversed by sodium azide or dithiothreitol. These findings suggest that oxidant-producing systems in saliva and airway secretions, such as heme peroxidases and other oxidizing substances, rapidly consume AA. Whereas oral supplementation resulted in detectable increases of AA in NLFs, its levels in tracheobronchial lining fluid, as measured by IS, were unaffected and remained relatively low, suggesting that AA may play a less significant antioxidant role in this compartment as compared with most other extracellular compartments.

Exhaled NO and eosinophil markers in blood, nasal lavage and sputum in children with asthma after withdrawal of budesonide

BACKGROUND

There is a need for controlled trials among children with asthma to evaluate and compare different markers of inflammation.

OBJECTIVE

Our goal was to investigate the effect of withdrawal of inhaled budesonide on repeated measurements of exhaled NO (ENO), peripheral blood eosinophils (PBE), sputum/NAL/serum-eosinophil cationic protein (ECP), bronchial hyperresponsiveness (BHR) and forced expiratory volume in 1 s (FEV(1)) in children with allergic asthma.

METHODS

Eighteen asthmatic children were randomly allocated to continue or discontinue use of inhaled budesonide. They were followed up, at six visits for 4 months with regular blood, serum, sputum, and NAL samples. Sixteen age-matched healthy children served as controls.

RESULTS

ENO, PBE, and S-ECP increased significantly in the withdrawal group (p < 0.05) but not in the continuous treatment group. No trend could be observed during the study for markers in sputum or in NAL in either group.

CONCLUSION

The present data provide evidence for the clinical usefulness of measuring ENO, PBE, and S-ECP and when combined they could help to avoid over- and undertreatment with corticosteroids in the growing child.

Eosinophil cationic protein and eosinophil protein X in the nasal lavage of children during the first 4 weeks of life. SPACE Collaborative Study Team

Eosinophil cationic protein (ECP) and eosinophil protein X (EPX) are well established as markers of eosinophil activation. We analyzed ECP and EPX concentrations in nasal lavage fluids (NALF) of 378 neonates during their first 4 weeks of life. Inclusion criteria were a positive history of parental allergy and a positive skin prick test or specific IgE (RAST class > or = 2) against at least one out of a panel of common aeroallergens in one or both parents. Twenty-four infants with no history of parental allergy were used as controls. A volume of 2 ml of 0.9% saline was instilled into each nostril and immediately recovered by a suction device. ECP and EPX were analyzed by radioimmunoassay. In 65 samples of three consecutive lavages, EPX was detected in nine samples (13.8%) in the control group, whereas it was detected in 197/360 samples (54.7%) in the study population. The corresponding figures for ECP were 17/65 (26.2%) in the control group and 173/365 (47.4%) in the study group. Both proteins showed a skewed distribution (median/5-95th percentiles for ECP: 0 microg/l [0-69.4] and EPX: 6.6 microg/l [0-73.2]). The differences between the control group and the study group were statistically significant, regardless of the allergic disease of the parents. In children of allergic parents, activation proteins of the eosinophil granulocyte are released on the nasal mucosal surface in about 50% of the studied population at the age of 4 weeks. This early onset of eosinophil activation in the nasal respiratory epithelium may reflect a genetic predisposition to allergy or early exposure to allergens.