Associations of Serum Clara Cell Protein 16 with Severity and Prognosis in Adults with Community-Acquired Pneumonia.

Background: Clara cell protein 16 (CC16) has multiple functions, including antioxidant, anti-inflammatory, and immune regulation properties. Nevertheless, the concrete function of CC16 in adult patients with community-acquired pneumonia (CAP) remained blurred. Methods: A total of 541 adult patients with CAP were recruited on admission. Peripheral blood specimens, clinical parameters, and demographic characteristics were collected. The concentration of serum CC16 was evaluated through ELISA. The relationships between serum CC16 and clinical parameters were appraised by Spearman or Pearson correlative analyses. The correlations of serum CC16 with severity and prognosis were assessed using linear or logistic regression models. Results: The level of CC16 was gradually decreased across with the elevated severity scores system of CAP. After treatment, the level of serum CC16 was upregulated. Correlative analyses found that serum CC16 was negatively related to inflammatory cytokines. Additionally, multivariate linear and logistic regression models revealed that serum CC16 was inversely associated with severity scores system. In addition, reduced serum CC16 on admission elevated the risks of vasoactive agent usage, ICU admission, and death during hospitalization. We observed an almost discriminatory ability for severity and death between serum CC16 and severity scores system, and were all obviously elevated compared to routine inflammatory and infectious markers. Conclusion: There are substantially inverse correlations between serum CC16 level on admission with severity scores and poorly prognostic outcomes, indicating that CC16 is involved in the pathophysiological process of CAP. This study is helpful for establishing the potential application of serum CC16 in risk evaluation and targeted treatment.

Health effects and known pathology associated with the use of E-cigarettes.

In recent years, new nicotine delivery methods have emerged, and many users are choosing electronic cigarettes (e-cigarettes) over traditional tobacco cigarettes. E-cigarette use is very popular among adolescents, with more than 3.5 million currently using these products in the US. Despite the increased prevalence of e-cigarette use, there is limited knowledge regarding the health impact of e-cigarettes on the general population. Based on published findings by others, E-cigarette is associated with lung injury outbreak, which increased health and safety concerns related to consuming this product. Different components of e-cigarettes, including food-safe liquid solvents and flavorings, can cause health issues related to pneumonia, pulmonary injury, and bronchiolitis. In addition, e-cigarettes contain alarmingly high levels of carcinogens and toxicants that may have long-lasting effects on other organ systems, including the development of neurological manifestations, lung cancer, cardiovascular disorders, and tooth decay. Despite the well- documented potential for harm, e-cigarettes do not appear to increase susceptibility to SARS-CoV- 2 infection. Furthermore, some studies have found that e-cigarette users experience improvements in lung health and minimal adverse effects. Therefore, more studies are needed to provide a definitive conclusion on the long-term safety of e-cigarettes. The purpose of this review is to inform the readers about the possible health-risks associated with the use of e-cigarettes, especially among the group of young and young-adults, from a molecular biology point of view.

[Refractory ceramic fibers induced changes in serum Clara cell protein 16 and surfactant protein D levels in rats].

Objective: To explore the effect of refractory ceramic fibers (RCFs) on the serum Clara cell protein 16 (CC16) and surfactant protein D (SP-D) levels in Wistar rats. Methods: In October 2020, 96 healthy adult male Wistar rats were randomly divided into control group (equal volume of normal saline) , low-dose group (5 mg/ml RCFs) , medium-dose group (10 mg/ml RCFs) and high-dose group (20 mg/ml RCFs) , and subjected to non-exposure tracheal instillation. After intraperitoneal anesthesia, the rats were instilled with 200 µl of RCFs suspension or normal saline, once every 3 days for a total of 4 times. At 7, 14, 28, and 90 days after exposure, 6 rats were sacrificed by blood sampling through the abdominal aorta. The organs were separated, histopathological changes of lungs were observed and lung injury scores were performed. The contents of serum CC16 and SP-D were determined by enzyme-linked immunosorbent assay (ELISA) . Results: RCFs could cause inflammatory cells in rat lung tissues, widening of the lung septum and destruction of alveolar structure. 7 days after exposure, the lung injury scores of rats in each dose group were higher than control group, and the lung injury score of the high-dose group was higher than low-dose group (P<0.05) . 14 and 90 days after exposure, the lung injury scores of the medium-dose and high-dose groups were higher than control group (P<0.05) . 28 days after exposure, the lung injury score of the high-dose group was higher than control group (P<0.05) . 7 days after exposure, the serum CC16 and SP-D concentrations of rats in the medium-dose and high-dose groups were significantly higher than control and low-dose groups (P<0.05) . 28 days after exposure, the serum CC16 concentrations of rats in the low-dose and medium-dose groups were significantly lower than those of the control and high-dose groups (P<0.05) . After 90 days of exposure, the serum CC16 concentrations of rats decreased with the increase of the exposure dose (F=28.853, P<0.01) , and the concentrations of SP-D increased with the increase of the exposure dose (F=25.636, P<0.01) . Conclusion: RCFs exposure may cause certain damage to rat Clara cells and alveolar-capillary barrier. The severity of lung injury can be indirectly understood through the dynamic changes of serum CC16 and SP-D.

Respiratory effects induced by occupational exposure to refractory ceramic fibers.

Refractory ceramic fibers (RCFs) are increasingly used as heating-insulated materials in various industries. However, toxicological and epidemiological studies focusing on the adverse effects of RCFs were still insufficient, particularly in China. We conducted a cross-sectional study to evaluate comprehensively the associations between occupational exposure to RCFs and respiratory health effects among Chinese workers. We measured and calculated cumulative RCFexposure levels of RCFs workers from the biggest RCFs factory in China. In total, 430 RCF-exposed workers and 121 controls were enrolled in this study. Physical examinations of the respiratory system were performed and serum levels of biomarkers including Clara cell protein 16 (CC16), surfactant protein D (SP-D), transforming growth factor ß1 (TGF-ß1), and 8-hydroxy-2'-deoxyguanosine (8-OHdG) were determined among all subjects. RCF exposure workers showed a higher prevalence rate of respiratory symptoms (cough: 11.9%) and lower levels of small airways function indices (V50 %: 82.71 ± 20.01, maximal mid expiratory flow (MMEF)%: 81.08 ± 19.56) compared with the control group (cough: 5.0%, V50 %: 90.64 ± 24.36, MMEF%: 88.83 ± 24.22). RCFs workers showed higher levels of TGF-ß1 (31.04 ng/mL) and 8-OHdG (130.72 ng/mL) and lower levels of CC16 (3.68 ng/mL) compared with the controls (TGF-ß1: 26.63 ng/mL, 8-OHdG: 106.86 ng/mL, CC16: 5.65 ng/mL). After adjusting for covariates, cumulative RCF exposure levels showed significant positive associations with the levels of TGF-ß1 and 8-OHdG and negative association with the level of CC16. Occupational RCF exposure could induce adverse respiratory health effects, including cough and small airways damage, which may correlate to the altered levels of lung damage markers (CC16 and TGF-ß1) and oxidative markers (8-OHdG).

Exogenous Clara cell protein 16 attenuates silica particles-induced inflammation in THP-1 macrophages by down-regulating NF-κB and caspase-1 activation.

Inhalation of silica particles leads to pulmonary inflammatory responses. Clara cell protein 16 (CC16) has been reported to played a protective role in inflammatory lung diseases. However, its role on silica particles-induced inflammation has not been fully clarified. In this study, THP-1 macrophages were exposed to 75 µg/cm2 silica particles with or without 2 µg/mL exogenous CC16 (recombinant CC16, rCC16) for 24 hr. The production of inflammatory cytokines, including interleukin (IL)-1ß, tumor necrosis factor (TNF)-α and IL-6, in the cell supernatants of different groups was detected through ELISA kits and real-time RT-PCR, respectively. The nuclear translocation of nuclear factor (NF)-κB, protein levels of pro-IL-1ß, the nucleotide-binding domain-like receptor protein 3 (NLRP3) and caspase-1 were evaluated via immunofluorescence or western blot. Results showed that, at 75 µg/cm2 silica particle concentration, the treatment of rCC16 significantly decreased IL-1ß, TNF-α and IL-6 protein release and mRNA levels in THP-1 macrophages. Compared to those only exposed to silica particles, THP-1 macrophages exposed to both silica particles and rCC16 showed significantly lower nuclear levels and higher cytosol levels of NF-κB p65, as well as lower co-localization coefficients through immunofluorescence. Additionally, the administration of rCC16 significantly attenuated the increase of pro-IL-1ß, NLRP3 and caspase-1 levels induced by silica particle exposure. Our results suggested that exogenous CC16 could inhibit silica particles-induced inflammation in THP-1 macrophages, mainly through suppressing NF-κB pathway and caspase-1 activation.

Correlation of Nasal Fluid Biomarkers and Symptoms in Patients with Persistent Allergic Rhinitis.

OBJECTIVES: This study investigated whether the biomarkers present in nasal fluid reflect the severity of symptoms in patients with persistent allergic rhinitis (PAR). METHODS: We enrolled 29 PAR patients complaining of nasal symptoms and testing positive to skin prick test. Patients' total nasal symptom score (TNSS) was measured and their nasal lavage fluid (NALF) was collected. The levels of biomarkers including Clara cell protein 16 (CC16), tryptase, and interleukin 5 (IL-5) in NALF were determined via enzyme-linked immunosorbent assay (ELISA). RESULTS: PAR patients were classified into persistent mild and persistent moderate-to-severe groups according to the Allergic Rhinitis and its Impact on Asthma (ARIA) guidelines. The CC16 alone was significantly negatively correlated with TNSS (P < .05). Further, the CC16 level was significantly lower in persistent moderate-to-severe group than persistent mild group of patients (P < .05). CONCLUSIONS: The levels of CC16 alone among several NALF biomarkers showed an inverse correlation with symptoms of PAR patients.

The clinical value of combined detection of serum angiopoietin 2 and Clara cell protein 16 in the early diagnosis of acute respiratory distress syndrome / 中华急诊医学杂志

Objective To investigate the clinical value of combined detection of serum angiopoietin 2 (Ang-2) and Clara cell protein 16 (CC16) in the early diagnosis of acute respiratory distress syndrome (ARDS).Methods Two hundred critical patients, treated at the Department of Critical Care Medicine, Bao'an District People's Hospital, Shenzhen during March 2015 and September 2016,were included in the study. According to the Berlin standard, patients were divided into two groups (n=100 each group): the ARDS group and non-ARDS group.The serum levels of Ang-2 and CC16 were measured by enzyme-linked immunosorbent assay (ELISA) on the first and second day of admission for each patient, in addition to completing APACHEⅡ score, medical history, vital signs collection and other biochemical indicators detection. Finally, paired-samplest test was used to analyze the data. The multiple ROC curve was used to calculate the area under the curve of the reference index of the serum levels of Ang-2 and CC16 on the first and second day.Results On the first and second day, the serum levels of Ang-2 and CC16 were significantly higher in ARDS patients than those in non-ARDS patients, and there was a correlation between the serum levels of Ang-2 and CC16 in ARDS patients. The ROC curve showed that the combined detection of Ang-2 and CC16 on the first day achieved a highest sensitivity of 75.9％ and detection of CC16 on the first day achieved a highest specificity of 70.2％. Conclusion Single-detection of serum levels of Ang-2 and CC16 could be used for early diagnosis of ARDS, and the combined detection of both has a higher sensitivity than single detection.

The clinical value of combined detection of serum angiopoietin 2 and Clara cell protein 16 in the early diagnosis of acute respiratory distress syndrome / 中华急诊医学杂志

Objective@#To investigate the clinical value of combined detection of serum angiopoietin 2 (Ang-2) and Clara cell protein 16 (CC16) in the early diagnosis of acute respiratory distress syndrome (ARDS).@*Methods@#Two hundred critical patients, treated at the Department of Critical Care Medicine, Bao'an District People's Hospital, Shenzhen during March 2015 and September 2016,were included in the study. According to the Berlin standard, patients were divided into two groups (n=100 each group): the ARDS group and non-ARDS group.The serum levels of Ang-2 and CC16 were measured by enzyme-linked immunosorbent assay (ELISA) on the first and second day of admission for each patient, in addition to completing APACHEⅡ score, medical history, vital signs collection and other biochemical indicators detection. Finally, paired-samples t test was used to analyze the data. The multiple ROC curve was used to calculate the area under the curve of the reference index of the serum levels of Ang-2 and CC16 on the first and second day.@*Results@#On the first and second day, the serum levels of Ang-2 and CC16 were significantly higher in ARDS patients than those in non-ARDS patients, and there was a correlation between the serum levels of Ang-2 and CC16 in ARDS patients. The ROC curve showed that the combined detection of Ang-2 and CC16 on the first day achieved a highest sensitivity of 75.9% and detection of CC16 on the first day achieved a highest specificity of 70.2%.@*Conclusion@#Single-detection of serum levels of Ang-2 and CC16 could be used for early diagnosis of ARDS, and the combined detection of both has a higher sensitivity than single detection.

Prognostic significance of surfactant protein A, surfactant protein D, Clara cell protein 16, S100 protein, trefoil factor 3, and prostatic secretory protein 94 in idiopathic pulmonary fibrosis, sarcoidosis, and chronic pulmonary obstructive disease.

BACKGROUND: Identification of serum and bronchoalveolar lavage fluid (BALF) biomarkers may facilitate diagnosis and prognostication in various lung disorders. OBJECTIVE: Serum and BALF levels of surfactant protein A (SP-A), surfactant protein D (SP-D), Clara cell protein 16 (CC16), S100 protein, trefoil factor 3 (TFF3), and prostatic secretory protein 94 (PSP94) were evaluated in 94 consecutive patients (idiopathic pulmonary fibrosis (IPF; n=18), sarcoidosis (n=25), chronic obstructive pulmonary disease (COPD; n=51)), and in 155 healthy controls. METHODS: Biomarkers were measured at diagnosis and compared with disease characteristics. Both uniparametric and multiparametric analyses were used. RESULTS: Seven significant correlations were found: 1) BALF PSP94 level correlated with prognosis of sarcoidosis (P=0.035); 2) BALF SP-D level with pulmonary functions in IPF (P=0.032); 3) BALF SP-D and TFF3 with IPF mortality (P=0.049 and 0.017, respectively); 4) serum TFF3 level with COPD mortality (P=0.006,); 5) serum SP-A with pulmonary functions impairment in IPF (P=0.011); 6) serum SP-D level was associated with HRCT interstitial score in IPF (P=0.0346); and 7) serum SP-A was associated with staging of COPD according to spirometry (P<0.001). Moreover, our analysis showed that some biomarker levels differed significantly among the diseases: 1) BALF SP-D level differed between sarcoidosis and IPF; 2) serum SP-A level differed among IPF, sarcoidosis, COPD and was also different from healthy controls; 3) serum S100A6, S100A11 levels differed among IPF, sarcoidosis, COPD from healthy controls 4) serum SP-D, CC16, TFF-3 levels distinguished IPF patients from healthy controls; and 5) serum CC16, TFF3, PSP94 distinguished COPD patients from healthy controls. Our study shows that some of selected biomarkers should have prognostic value in the analysed lung disorders. On the other hand, these biomarkers do not appear to be unequivocally suitable for differential diagnosis of these disorders.

Clara cell protein 16 and eosinophil cationic protein production in chronically inflamed sinonasal mucosa.

BACKGROUND: Clara cell protein 16 (CC16) is an anti-inflammatory protein mainly expressed in the epithelial cells in the upper and lower airways. Eosinophil cationic protein (ECP) is an important marker of eosinophil activity in chronic inflammatory sinonasal diseases. The aim of this study was to evaluate mucosal production of CC16 and ECP in patients with perennial allergic rhinitis (PAR), nonallergic and allergic patients with chronic rhinosinusitis with nasal polyposis (CRSwNP), before and after nasal corticosteroid administration. METHODS: Twenty patients with PAR, 20 nonallergic CRSwNP patients, 20 allergic CRSwNP patients, and 20 healthy controls were included. Mucosal cytology samples were taken from all participants for quantification of eosinophils. CC16 and ECP levels were measured in the nasal secretion samples. The patients with chronic sinonasal inflammation were treated with fluticasone nasal spray for 14 days. Nasal symptoms assessment, cytological examination, and CC16 and ECP nasal fluid measurements were performed before and after the corticosteroid treatment. RESULTS: Mean CC16 concentrations in nasal secretions were significantly lower in patients with PAR (p < 0.05) and allergic CRSwNP patients (p < 0.01) compared to controls. Mean ECP levels were significantly higher in patients with PAR, nonallergic CRSwNP patients, and allergic CRSwNP patients compared to the control group (p < 0.001, p < 0.01, p < 0.001, respectively). After nasal corticosteroid therapy, we found a highly significant increase of CC16 (p < 0.001) and reduction of ECP (p < 0.001) in nasal secretions in all 3 groups of patients. CONCLUSION: CC16 and ECP measured in nasal secretions could be reliable markers for assessment of the recovery function of sinonasal mucosa during corticosteroid treatment.

Damage-associated molecular pattern and innate cytokine release in the airways of competitive swimmers.

BACKGROUND: Daily intensive exercise by elite athletes can result in exercise-induced asthma especially in elite swimmers and this may be linked to epithelial damage. OBJECTIVE: To study airway epithelial damage and release of damage-associated molecular patterns (DAMPs) after intensive exercise in elite athletes and controls. METHODS: We recruited competitive swimmers (n = 26), competitive indoor athletes (n = 13) and controls (n = 15) without any history of asthma. Lung function was measured before, immediately after and 24 h after a 90-min intensive exercise protocol. Sputum induction was performed at baseline and 24 h after exercise. Exercise-induced bronchoconstriction (EIB) was assessed by the eucapnic voluntary hyperventilation test. RESULTS: Baseline sputum uric acid, high mobility group box-1, CXCL8 mRNA, sputum neutrophils and serum Clara cell protein-16 (CC-16) were significantly higher in competitive swimmers compared with controls. Intensive swimming for 90 min resulted in an increase of sputum IL-1ß, IL-6 and TNF mRNA in competitive swimmers, and of sputum IL-6 mRNA and sputum neutrophils in controls. Although all participants were asymptomatic, seven competitive swimmers, one indoor athlete and one control met the criteria for EIB. CONCLUSION: Our findings show that the intensive training combined with exposure to by-products of chlorination induces airway epithelial damage in competitive swimmers. This is associated with increased damage-associated molecular patterns, innate cytokine release and neutrophilic airway inflammation.

The clinical investigation of clara cell protein 16 for the early diagnosis of acute respiratory distress syndrome / 中华急诊医学杂志

Objective To explore the clinical value of clara cell protein 16 (Cc 16) in the early diagnosis of ARDS in critically ill patients.Methods A total of 55 critically ill patients admitted between March 2013 and December 2013 in the Intensive Care Unit were enrolled for study.The inclusion criteria were as follows:sepsis,pneumonia,multiple injuries,patients after emergency or elective operation and non-cardiogenic diseases,whereas the exclusion criteria were cardiogenic pulmonary edema,age ≤ 18 years or≥80 years and disease course prolonged over one week.The level of serum Cc16 was detected with enzyme linked immunosorbent assay (ELISA).In addition,data of other biochemical examinations,the Acute Physiology and Chronic Health Evaluation (APACHE]Ⅱ) score and the relevant medical data were documented.The patients were divided into ARDS groups and non-ARDS groups based on clinical data met Berlin definition.Results The sensitivity and specificity of serum Cc16 for diagnosis of ARDS were 92％ and 80％,respectively with the area under the curve being 0.92,which were better than those of APACHE Ⅱ score,D-dimer,C-reactive protein,N-terminal pro-brain natriuretic peptide and serum albumin detected by the means of receiver operating characteristic curve,and cut off value was 20.62 ng/L.The bivariate analysis showed there was negative correlation between Cc16 and oxagenation index in ARDS patients and the Pearson correlation coefficient of serum Cc16 with oxygenation index was r =-0.342 (P =0.04).The results of one-way analysis of variance showed difference in level of Cc16 between subgroups (F =15.76,P =0.005 17).The level of Ccl6 in severe ARDS group was (64.18 ± 12.95) ng/L which was higher than that in mild ARDS group (35.87 ± 11.28) ng/L (P =0.001 14),and in moderate ARDS group (38.66 ± 20.14) ng/L (P =0.004 9),and in non-ARDS group (16.72 ± 8.74) ng/L (P =0.000 32).There was no statistically significant difference in Cc16 level between mild ARDS group and moderate ARDS group (P =0.682).The level of serum Ccl6 did not correlate with type or days of respiratory ventilation support,28-day survival rate or 120-hour survival rate and days of ICU stay and hospital stay.Conclusions The diagnostic value of serum Cc16 is very high in determining the presence and severity of ARDS in addition to the Berlin criteria in critically ill patients accurately assessing degree of lung injury.

Effect of therapeutic arsenic exposure on pulmonary function.

AIM: Arsenic-contaminated drinking water has been associated with respiratory diseases and lung function impairment. Oral arsenic trioxide (ATO) is a standard treatment for acute promyelocytic leukaemia. This study aimed to explore the effect of therapeutic exposure to arsenic on lung function. PATIENTS AND METHOD: This was a case-control cross-sectional study on patients with haematological malignancies with or without exposure to ATO. Full lung function tests and serum Clara cell protein 16 (CC16) were measured. RESULTS: There were 57 cases (arsenic exposed) and 57 matched controls (arsenic non-exposed) recruited. Among cases, the median duration of ATO exposure was 519 (194-1259) days. The mean FEV(1)/FVC ratio, FEV(1) (% predicted), and RV/TLC (%), as well as % subjects with FEV(1)/FVC below lower limits of normal (LLN), were similar in the two groups with or without arsenic exposure. However the mean TLC (% predicted) and DLCO/VA were significantly higher in arsenic-exposed versus non-exposed group (p = 0.01 and p = 0.008 respectively). There were mildly reduced FEV(1)/FVC ratio and FEF(25-75) (% predicted), largely within normal limits, among high level arsenic exposure compared with non-exposure (p = 0.01 and p = 0.05 respectively). Serum CC16 was comparable among both arsenic exposed and non-exposed groups. CONCLUSION: Therapeutic use of oral ATO for a median of around 1.5 years was not associated with clinically significant lung function impairment.