scholarly journals The Development of Integrin Alpha-8 Deficient Lungs Shows Reduced and Altered Branching and a Correction of the Phenotype During Alveolarization

2020 ◽  
Vol 11 ◽  
Author(s):  
Tiziana P. Cremona ◽  
Andrea Hartner ◽  
Johannes C. Schittny
Keyword(s):  
Lung Development ◽  
Therapeutic Benefit ◽  
Beta Subunits ◽  
Wild Type ◽  
Mouse Tissues ◽  
Spontaneous Contractions ◽  
Extracellular Matrix Receptors ◽  
Stereological Investigation ◽  
Potential Therapeutic Benefit

Lung development involves epithelial–mesenchymal interactions and integrins represent one of the key elements. These extracellular matrix receptors form hetero-dimers of alpha and beta subunits. The integrin α8β1 is highly expressed in mouse tissues, including lung. It forms a cellular receptor for fibronectin, vitronectin, osteopontin, nephronectin, and tenascin-C. This study aims to investigate the role of the integrin α8-subunit (α8) during lung development. Wild type and α8-deficient lungs were explanted at embryonic days 11.5/12.5. After 24–73 h in culture α8-deficient lung explants displayed reduced growth, reduced branching, enlarged endbuds, altered branching patterns, and faster spontaneous contractions of the airways as compared to wild type. Postnatally, a stereological investigation revealed that lung volume, alveolar surface area, and the length of the free septal edge were significantly reduced in α8-deficient lungs at postnatal days P4 and P7. An increased formation of new septa in α8-deficient lungs rescued the phenotype. At day P90 α8-deficient lungs were comparable to wild type. We conclude that α8β1 takes not only part in the control of branching, but also possesses a morphogenic effect on the pattern and size of the future airways. Furthermore, we conclude that the phenotype observed at day P4 is caused by reduced branching and is rescued by a pronounced formation of the new septa throughout alveolarization. More studies are needed to understand the mechanism responsible for the formation of new septa in the absence of α8β1 in order to be of potential therapeutic benefit for patients suffering from structural lung diseases.

scholarly journals Loss of Protein Kinase D2 Activity Protects Against Bleomycin-induced Dermal Fibrosis in Mice

2021 ◽  
Author(s):  
Liping Chen ◽  
Jinjun Zhao ◽  
Yapeng Chao ◽  
Adhiraj Roy ◽  
Wenjing Guo ◽  
...  
Keyword(s):  
Protein Kinase ◽  
Myeloid Cells ◽  
Fiber Formation ◽  
Separate Experiment ◽  
Wild Type ◽  
Dermal Fibrosis ◽  
Fibrotic Process ◽  
Mouse Tissues ◽  
Tgf Β1

AbstractBackgroundDermal fibrosis occurs in many human diseases, particularly systemic sclerosis (SSc) where persistent inflammation leads to collagen deposition and fiber formation in skin and multiple organs. The family of protein kinase D (PKD) has been linked to inflammatory responses in various pathological conditions, however, its role in inflammation-induced dermal fibrosis has not been well defined. Here, using a murine fibrosis model that gives rise to dermal lesions similar to those in SSc, we investigated the role of PKD in dermal fibrosis in mice lacking PKD2 activity.MethodsHomozygous kinase-dead PKD2 knock-in mice (PKD2SSAA/SSAA-KI) were obtained through intercrossing mice heterozygous for PKD2S707A/S711A (PKD2SSAA). The wild-type and KI mice were subjected to repeated subcutaneous injection of bleomycin (BLM) to induce dermal inflammation and fibrosis. As controls, mice were injected with PBS. At the end of the experiment, mouse skin at the injection site was dissected, stained, and analyzed for morphological changes and expression of inflammatory and fibrotic markers. PKD-regulated signaling pathways were examined by real-time RT-qPCR and Western blotting. In a separate experiment, BLM-treated mice were administered with or without a PKD inhibitor, CRT0066101 (CRT). The effects of CRT on dermal fibrosis were analyzed similarly. The identity of the PKD expressing cells were probed using myeloid lineage markers CD45, CD68 in BLM-treated mouse tissues.ResultsDermal thickness and collagen fibers of kinase-dead PKD2-KI mice were significantly reduced in response to BLM treatment as compared to the wild-type mice. These mice also exhibited reduced α-smooth muscle actin (α-SMA) and collagen expression. At molecular levels, both transforming growth factor β1 (TGF-β1) and interleukin-6 (IL-6) mRNAs were decreased in the KI mice treated with BLM as compared to those in the wild-type mice. Similarly, CRT significantly blocked BLM-induced dermal fibrosis and inhibited the expression of α-SMA, collagen, and IL-6 expression. Further analysis indicated that PKD2 was mainly expressed in CD45+/CD68+ myeloid cells that could be recruited to the lesional sites to promote the fibrotic process of the skin in response to BLM.ConclusionsKnock-in of the kinase-dead PKD2 or inhibition of PKD activity in mice protected against BLM-induced dermal fibrosis by reducing dermis thickness and expression of fibrotic biomarkers including α-SMA, collagen, and inflammatory/fibrotic mediators including TGF-β1 and IL-6. PKD2 does this potentially through modulating the recruitment and function of myeloid cells in skin of BLM-treated mice. Overall, our study demonstrated a potential critical role of PKD catalytic activity in inflammation-induced dermal fibrosis.

scholarly journals Amelioration of DSS-induced Acute Colitis in Mice by Recombinant Monomeric Human Interleukin-22

2021 ◽  
Author(s):  
Suhyun Kim ◽  
Eun-Hye Hong ◽  
Cheol-Ki Lee ◽  
Yiseul Ryu ◽  
Hyunjin Jeong ◽  
...  
Keyword(s):  
Comprehensive Evaluation ◽  
Enzymatic Reaction ◽  
Therapeutic Benefit ◽  
Biologically Active ◽  
Acute Colitis ◽  
Inflammatory Cytokine Production ◽  
Interleukin 22 ◽  
Transcription 3 ◽  
Potential Therapeutic Benefit

Interleukin-22 (IL-22), a pleiotropic cytokine, is known to have a profound effect on the regeneration of damaged intestinal barriers. The potential therapeutic benefit of IL-22 is expected to be exploited in the attenuation and treatment of colitis. However, because of the disease-promoting role of IL-22 in chronic inflammation, a comprehensive evaluation is required to translate IL-22 into the clinical domain. Here, we present the effective production of soluble human IL-22 in bacteria to prove whether recombinant IL-22 has the ability to ameliorate colitis and inflammation. IL-22 was expressed in the form of a biologically active monomer and a non-functional dimer. Monomeric IL-22 (mIL-22) was highly purified through a series of three separate chromatographic methods and an enzymatic reaction. We reveal that the resulting mIL-22 is correctly folded and is able to phosphorylate signal transducer and activator of transcription 3 in HT-29 cells. Subsequently, we demonstrate that mIL-22 enables the attenuation of dextran sodium sulfate-induced acute colitis in mice, as well as the suppression of pro-inflammatory cytokine production. Collectively, our results suggest that the recombinant mIL-22 is suitable to study the biological roles of endogenous IL-22 in immune responses and can be developed as a biological agent associated with inflammatory disorders.

scholarly journals Soluble guanylate cyclase modulates alveolarization in the newborn lung

2013 ◽  
Vol 305 (8) ◽  
pp. L569-L581 ◽  
Author(s):  
Patricia R. Bachiller ◽  
Katherine H. Cornog ◽  
Rina Kato ◽  
Emmanuel S. Buys ◽  
Jesse D. Roberts
Keyword(s):  
Guanylate Cyclase ◽  
Lung Development ◽  
Soluble Guanylate Cyclase ◽  
Somatic Growth ◽  
Wild Type ◽  
Body Weights ◽  
Mean Linear Intercept ◽  
Cellular Markers ◽  
Α1 Subunit

Nitric oxide (NO) regulates lung development through incompletely understood mechanisms. NO controls pulmonary vascular smooth muscle cell (SMC) differentiation largely through stimulating soluble guanylate cyclase (sGC) to produce cGMP and increase cGMP-mediated signaling. To examine the role of sGC in regulating pulmonary development, we tested whether decreased sGC activity reduces alveolarization in the normal and injured newborn lung. For these studies, mouse pups with gene-targeted sGC-α1 subunit truncation were used because we determined that they have decreased pulmonary sGC enzyme activity. sGC-α1 knockout (KO) mouse pups were observed to have decreased numbers of small airway structures and lung volume compared with wild-type (WT) mice although lung septation and body weights were not different. However, following mild lung injury caused by breathing 70% O2, the sGC-α1 KO mouse pups had pronounced inhibition of alveolarization, as evidenced by an increase in airway mean linear intercept, reduction in terminal airway units, and decrease in lung septation and alveolar openings, as well as reduced somatic growth. Because cGMP regulates SMC phenotype, we also tested whether decreased sGC activity reduces lung myofibroblast differentiation. Cellular markers revealed that vascular SMC differentiation decreased, whereas myofibroblast activation increased in the hyperoxic sGC-α1 KO pup lung. These results indicate that lung development, particularly during hyperoxic injury, is impaired in mouse pups with diminished sGC activity. These studies support the investigation of sGC-targeting agents as therapies directed at improving development in the newborn lung exposed to injury.

scholarly journals Connexin43 Is Required for the Effective Activation of Spleen Cells and Immunoglobulin Production

2019 ◽  
Vol 20 (22) ◽  
pp. 5789 ◽  
Author(s):  
Yanru Huang ◽  
Zhimin Mao ◽  
Xiling Zhang ◽  
Xiawen Yang ◽  
Norifumi Sawada ◽  
...  
Keyword(s):  
Cell Activation ◽  
Lymphocyte Activation ◽  
Specific Protein ◽  
Wild Type ◽  
Spleen Cells ◽  
Cx43 Expression ◽  
Cellular Processes ◽  
Mouse Tissues ◽  
Oxidative State

Gap junctions (Gjs), formed by specific protein termed connexins (Cxs), regulate many important cellular processes in cellular immunity. However, little is known about their effects on humoral immunity. Here we tested whether and how Gj protein connexin43 (Cx43) affected antibody production in spleen cells. Detection of IgG in mouse tissues and serum revealed that wild-type (Cx43+/+) mouse had a significantly higher level of IgG than Cx43 heterozygous (Cx43+/−) mouse. Consistently, spleen cells from Cx43+/+ mouse produced more IgG under both basal and lipopolysaccharide (LPS)-stimulated conditions. Further analysis showed that LPS induced a more dramatic activation of ERK and cell proliferation in Cx43+/+ spleen cells, which was associated with a higher pro-oxidative state, as indicated by the increased NADPH oxidase 2 (NOX2), TXNIP, p38 activation and protein carbonylation. In support of a role of the oxidative state in the control of lymphocyte activation, exposure of spleen cells to exogenous superoxide induced Cx43 expression, p38 activation and IgG production. On the contrary, inhibition of NOX attenuated the effects of LPS. Collectively, our study characterized Cx43 as a novel molecule involved in the control of spleen cell activation and IgG production. Targeting Cx43 could be developed to treat certain antibody-related immune diseases.

Prognosticating role of serum eosinophils on immunotherapy efficacy in patients with advanced melanoma

Immunotherapy ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 217-225 ◽  
Author(s):  
Adi Kartolo ◽  
Ryan Holstead ◽  
Wilma Hopman ◽  
Tara Baetz
Keyword(s):  
Retrospective Study ◽  
Therapeutic Benefit ◽  
Advanced Melanoma ◽  
Interval Time ◽  
Start Date ◽  
Peripheral Eosinophil ◽  
Potential Therapeutic Benefit ◽  
Eosinophil Counts

Aim: To evaluate serum eosinophilia (≥500 peripheral eosinophil counts/microliter) in prognosticating immunotherapy (IO) efficacy. Methodology: A retrospective study of 86 patients with advanced melanoma on PD-1 inhibitors. Results: Eosinophilia-on-IO was an independent prognosticating factor for median OS (HR :0.223; 95% CI: 0.088–0.567; p = 0.002). ‘Late eosinophilia’ (≥1 year from IO start date) group had better median OS (31.9 vs 24.1 vs 13.0 months; p = 0.002) when compared with ‘early eosinophilia’ (<1 year from IO start date) and ‘no eosinophilia’ groups, respectively. Conclusion: Eosinophilia-on-IO and its timing were associated with better IO efficacy in patients with advanced melanoma. Our findings provided insights on potential therapeutic benefit of inducing eosinophilia at certain interval time to obtain a longer durable immunotherapy response.

scholarly journals Dictyostelium mutants lacking the cytoskeletal protein coronin are defective in cytokinesis and cell motility.

1993 ◽  
Vol 120 (1) ◽  
pp. 163-173 ◽  
Author(s):  
E L de Hostos ◽  
C Rehfuess ◽  
B Bradtke ◽  
D R Waddell ◽  
R Albrecht ◽  
...  
Keyword(s):  
Leading Edge ◽  
Gene Replacement ◽  
Actin Binding ◽  
Beta Subunits ◽  
Wild Type ◽  
Daughter Cells ◽  
Immunofluorescence Labeling ◽  
Mutant Cells

Coronin is an actin-binding protein in Dictyostelium discoideum that is enriched at the leading edge of the cells and in projections of the cell surface called crowns. The polypeptide sequence of coronin is distinguished by its similarities to the beta-subunits of trimeric G proteins (E. L. de Hostos, B. Bradtke, F. Lottspeich, R. Guggenheim, and G. Gerisch, 1991. EMBO (Eur. Mol. Biol. Organ.) J. 10:4097-4104). To elucidate the in vivo function of coronin, null mutants have been generated by gene replacement. The mutant cells lacking coronin grow and migrate more slowly than wild-type cells. When these cor- cells grow in liquid medium they become multinucleate, indicating a role of coronin in cytokinesis. To explore this role, coronin has been localized in mitotic wild-type cells by immunofluorescence labeling. During separation of the daughter cells, coronin is strongly accumulated at their distal portions including the leading edges. This contrasts with the localization of myosin II in the cleavage furrow and suggests that coronin functions independently of the conventional myosin in facilitating cytokinesis.

The role of WNT/b-catenin signaling in smooth muscle cells during lung development and repair

Pneumologie ◽  
2014 ◽  
Vol 68 (06) ◽  
Author(s):  
A Moiseenko ◽  
E El Agha ◽  
B MacKenzie ◽  
S De Langhe ◽  
S Bellusci
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Lung Development ◽  
Muscle Cells

Differential Role of Components of the Fibrinolytic System in the Formation and Removal of Thrombus Induced by Endothelial Injury

1999 ◽  
Vol 81 (04) ◽  
pp. 601-604 ◽  
Author(s):  
Hiroyuki Matsuno ◽  
Osamu Kozawa ◽  
Masayuki Niwa ◽  
Shigeru Ueshima ◽  
Osamu Matsuo ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
Thrombus Formation ◽  
Endothelial Injury ◽  
Fibrinolytic System ◽  
Tissue Type ◽  
Clot Lysis ◽  
Wild Type ◽  
Type Plasminogen Activator ◽  
Pai 1

SummaryThe role of fibrinolytic system components in thrombus formation and removal in vivo was investigated in groups of six mice deficient in urokinase-type plasminogen activator (u-PA), tissue-type plasminogen activator (t-PA), or plasminogen activator inhibitor-1 (PAI-1) (u-PA-/-, t-PA-/- or PAI-1-/-, respectively) or of their wild type controls (u-PA+/+, t-PA+/+ or PAI-1+/+). Thrombus was induced in the murine carotid artery by endothelial injury using the photochemical reaction between rose bengal and green light (540 nm). Blood flow was continuously monitored for 90 min on day 0 and for 20 min on days 1, 2 and 3. The times to occlusion after the initiation of endothelial injury in u-PA+/+, t-PA+/+ or PAI-1+/+ mice were 9.4 ± 1.3, 9.8 ± 1.1 or 9.7 ± 1.6 min, respectively. u-PA-/- and t-PA-/- mice were indistinguishable from controls, whereas that of PAI-1-/- mice were significantly prolonged (18.4 ± 3.7 min). Occlusion persisted for the initial 90 min observation period in 10 of 18 wild type mice and was followed by cyclic reflow and reocclusion in the remaining 8 mice. At day 1, persistent occlusion was observed in 1 wild type mouse, 8 mice had cyclic reflow and reocclusion and 9 mice had persistent reflow. At day 2, all injured arteries had persistent reflow. Persistent occlusion for 90 min on day 0 was observed in 3 u-PA-/-, in all t-PA-/- mice at day 1 and in 2 of the t-PA-/-mice at day 2 (p <0.01 versus wild type mice). Persistent patency was observed in all PAI-1-/- mice at day 1 and in 5 of the 6 u-PA-/- mice at day 2 (both p <0.05 versus wild type mice). In conclusion, t-PA increases the rate of clot lysis after endothelial injury, PAI-1 reduces the time to occlusion and delays clot lysis, whereas u-PA has little effect on thrombus formation and spontaneous lysis.

Sign in / Sign up

Export Citation Format

Share Document