Increased serum IL­41 associated with acute exacerbation of chronic obstructive pulmonary disease.

Interleukin (IL)-41 is a novel immunomodulatory cytokine involved in the pathogenesis of several inflammatory and metabolic illnesses. However, it remains unclear how IL-41 contributes to the pathogenesis of chronic obstructive pulmonary disease (COPD). Therefore, the aim of the present study was to explore the correlation between the expression level of IL-41 and acute exacerbation of COPD (AECOPD). In total, 107 patients with COPD and 56 healthy controls were recruited from the First Affiliated Hospital of Ningbo University (Ningbo, China). Serum IL-41, IL-6, and matrix metalloproteinase-2 (MMP-2) levels were evaluated using enzyme-linked immunosorbent assay. Serum amyloid A (SAA) and C-reactive protein (CRP) levels were assessed in the hospital laboratory. The levels of IL-41 were higher in the AECOPD group than in the stable COPD (SCOPD) and control groups (P<0.0001). IL-6, SAA and CRP levels, the percentage of neutrophils, as well as neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios were higher in the AECOPD group than those in the SCOPD and control groups. The smoking index was positively correlated with serum IL-41, CRP and SAA levels. The expression level of IL-41 was correlated with the number of acute exacerbations, severity of the exacerbations, and COPD assessment test scores in the AECOPD group. Examination of the receiver operating characteristic (ROC) curves showed that IL-41, especially when combined with other inflammatory factors, had a specific diagnostic value for AECOPD. According to the ROC curve analysis, the area under the curve (AUC) for IL-41 was 0.742 (P=0.051), and the AUC for IL-41 combined with other inflammatory factors was 0.925 (P=0.030). Increased serum IL-41 levels were associated with AECOPD and may play a role in the monitoring and evaluation of COPD.

Waldenström macroglobulinemia presenting as bilateral bloody pleural effusion: A case report.

RATIONALE: Pleural effusion, especially bilateral bloody pleural effusion, is a rare complication of Waldenström macroglobulinemia (WM). Pleural effusion in patients with WM has many causes, such as infection, tumor invasion of the pleura, and rupture of the thoracic duct or its branches. Patients with WM presenting to the respiratory department with chest tightness and shortness of breath need more differential diagnosis by respiratory physicians, which is helpful for effective treatment. Herein, we present a case of MV diagnosis in a patient with bilateral bloody pleural effusion. PATIENT CONCERN: Our patient is a 59-year-old man with WM presenting as having bilateral bloody pleural effusion. INTERVENTIONS: The patient was treated with pleural effusion drainage. After confirming the diagnosis, the patient was treated with rituximab, cyclophosphamide, and dexamethasone. OUTCOMES: Following these treatments, the patient's symptoms improved, and ultrasound showed a decrease in pleural effusion. LESSONS: Despite its favorable prognosis, the cause of pleural effusion in a patient with WM can be challenging to diagnose. The cause of pleural effusion should be considered a differential diagnosis when diagnosing patients diagnosed with WM.

Interleukin-41 diminishes cigarette smoke-induced lung inflammation in mice.

BACKGROUND: Chronic obstructive pulmonary disease (COPD) and other inflammatory lung illnesses are markedly exacerbated by cigarette smoke (CS). The novel cytokine interleukin (IL)-41 has immunoregulatory effects, but data on its function in lung inflammation caused by CS are limited and inconclusive. Our study aimed to investigate the ability of IL-41 to protect against CS-induced lung inflammation in vivo. METHODS: In this model, mice were exposed to six cigarettes three times daily for 1 h, with 4-hour intervals between exposures, for 5 consecutive days. Mice received an intraperitoneal dose of IL-41 or a negative control 1 day prior to their initial exposure to CS. On day 6, mice were sacrificed to assess the impact of IL-41 on CS-induced lung inflammation. RESULTS: We found that IL-41 pre-treatment alleviated pulmonary inflammatory infiltration and lung tissue lesions. IL-41 pre-treatment also limited CS-induced weight loss, and resulted in lower numbers of macrophages in the bronchoalveolar lavage fluid and lower percentages of neutrophils and monocytes in the blood. Furthermore, it promoted the polarization of M2 macrophages rather than M1 macrophages, as determined by immunohistochemistry. Consistent with its effects on M2 polarization, pre-treatment with IL-41 was associated with higher levels of IL-10 in the bronchoalveolar lavage fluid and lung tissues of CS-exposed animals and lower production of tumor necrosis factor-α, IL-6 and IL-1ß in the serum and lung tissues. CONCLUSIONS: These findings suggest that IL-41 could be used therapeutically to treat CS-induced lung inflammatory disorders as it inhibits CS-induced pulmonary inflammation when administered in vivo in mice.