The spike glycoprotein attached to the envelope of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) binds to and exploits angiotensin-converting enzyme 2 (ACE2) as an entry receptor to infect pulmonary epithelial cells. A subset of integrins that recognize the arginyl–glycyl–aspartic acid (RGD) sequence in the cognate ligands has been predicted in silico to bind the spike glycoprotein and, thereby, to be exploited for viral infection. Here, we show experimental evidence that the β1 integrins predominantly expressed on human pulmonary epithelial cell lines and primary mouse alveolar epithelial cells bind to this spike protein. The cellular β1 integrins support adhesive interactions with the spike protein independently of ACE2, suggesting the possibility that the β1 integrins may function as an alternative receptor for SARS-CoV-2, which could be targeted for the prevention of viral infections.
Septic shock/severe sepsis is a deregulated host immune system response to infection that leads to life-threatening organ dysfunction. Lung inflammation as a form of acute lung injury (ALI) is often induced in septic shock. Whereas macrophages and neutrophils have been implicated as the principal immune cells regulating lung inflammation, group two innate lymphoid cells (ILC2s) have recently been identified as a new player regulating immune homeostasis. ILC2 is one of the three major ILC subsets (ILC1s, ILC2s, and ILC3s) comprised of newly identified innate immune cells. These cells are characterized by their ability to rapidly produce type 2 cytokines. ILC2s are predominant resident ILCs and, thereby, have the ability to respond to signals from damaged tissues. ILC2s regulate the immune response, and ILC2-derived type 2 cytokines may exert protective roles against sepsis-induced lung injury. This focused review not only provides readers with new insights into the signaling mechanisms by which ILC2s modulate sepsis-induced lung inflammation, but also proposes ILC2 as a novel therapeutic target for sepsis-induced ALI.
17 July 2017 in European Journal of Cardio-Thoracic Surgery
The real-time endoscopic colour and fluorescence-merged imaging system, using intravenous injection of indocyanine green (ICG), allows a clear surgical view, which facilitates identification of the pulmonary inter-segmental plane in thoracoscopic surgery. However, the staining time is too short to mark and cut the intersegmental plane, because the mean washout time of ICG is only a few minutes in the clinical setting. To overcome this limitation, we have developed a new technique for prolongation of ICG staining time. The technique consists of 2 simple steps. First, we cut the targeted segmental artery, vein and bronchus. Second, ICG is injected intravenously, followed by temporary clamping of the pulmonary vein of entire lobe, including the segments. Our technique may not only offer prolonged washout time for marking the surface of the lung but also facilitate identification of precise intersegmental plane to be cut.
Background: Although complete video-assisted thoracic surgery (C-VATS) has been demonstrated to have several advantages compared with conventional thoracotomy, there are few reports on the clinical feasibility of C-VATS for CPAM in infants. Methods: We retrospectively evaluated 13 consecutive patients (neonates 4; infants 9) surgically treated for congenital pulmonary airway malformation (CPAM) from 1 January 2008 to 31 March 2017. Results: In the group of neonates, all 4 cases were prenatally diagnosed and they underwent semi-emergent surgery after birth due to respiratory failure. In the group of 9 infants, 5 cases were prenatally diagnosed and 4 cases were diagnosed at age >2.5 years due to symptoms associated with pulmonary cystic infection. Pulmonary resection consisted of the following: 8 lobectomies, 1 segmentectomy, 2 wedge resection, 1 fractionated lung resection and 1 lobectomy with segmentectomy. Overall, there were 9 thoracotomy and 4 thoracoscopic surgeries. Mean operation time was 162 min (range, 67–290 min) and blood loss was 21 mL (range, 0–74 mL) on average. There were no complications such as thoracic deformity or respiratory failure, however in 2 of those who underwent segmentectomy the cystic remnant remained. No statistically significant differences were observed between the thoracotomy Group and C-VATS group in terms of age and height at intervention, operation time, blood loss, postoperative day of drain removal, and length of hospital stay after surgery. However, only the average body weight was heavier in C-VATS group (P=0.03). Conclusions: Since early surgical resection of asymptomatic CPAM is often recommended for the prevention of infections and the development of lung malignancy, we recommend performing surgery after the age of 1 year if the patient’s condition is stable. Furthermore, C-VATS lobectomy may be feasible if they are older than 18 months or weigh more than 10 kg.
Breast cancer is the most common cancer in women worldwide, and lung metastasis is one of the most frequent distant metastases. When breast cancer metastasizes to the lung, group 2 innate lymphoid cells (ILC2s) are thought to promote tumor growth via the activation of myeloid-derived suppressor cells (MDSCs), which are known to negatively regulate anticancer immune responses. However, it remains to be elucidated exactly how this ILC2–MDSC interaction is involved in tumor growth during metastases formation. Using a 4T1/LM4 breast cancer mouse model, we found that ILC2s were activated in both the micro- and macrometastatic regions, suggesting sustained activation throughout the metastatic cascades via IL-33/ST2 signaling. Consistent with IL-13 secretion from activated ILC2s, the frequencies of polymorphonuclear (PMN)- and monocytic (M)-MDSCs were also significantly elevated during the progression from micro- to macrometastatic cancer. However, the effects of ILC2-induced MDSC functionality on the microenvironment differed in a metastatic-stage-specific manner. Our findings indicate that ILC2s may induce the immunosuppressive functions of MDSCs during the later stages of metastasis. Concomitantly, ILC2 may instigate extracellular matrix remodeling by PMN-MDSC activation during the early stages of metastasis. These metastatic-stage-specific changes may contribute to metastatic tumor growth in the microenvironment of breast cancer lung metastasis.