scholarly journals Flow cytometric study of the type II pneumocyte cell cycle in vivo and in vitro

Cytometry ◽  
1994 ◽  
Vol 15 (1) ◽  
pp. 46-52 ◽  
Author(s):  
Bruce D. Uhal
1993 ◽  
Vol 264 (2) ◽  
pp. L153-L159 ◽  
Author(s):  
B. D. Uhal ◽  
M. D. Etter

Hypertrophic and normotrophic type II pneumocytes were isolated from pneumonectomized adult rats by unit gravity (1 g) sedimentation or by fluorescence-activated cell sorting (FACS). In vivo or in vitro, hypertrophic cells incorporated significantly more 5-bromo-2'-deoxyuridine or tritiated thymidine into acid-insoluble material than did normotrophic cells. By FACS analysis of cell subpopulations isolated by 1 g, > 97% of normotrophic cells had G0-phase DNA content. In contrast, the cell cycle distribution of hypertrophic cells was 75% G1, 5% S, and 20% G2/M phases. Rates of incorporation of tritiated choline into total cellular phosphatidylcholine (PC) were identical in type II cells isolated from normal or pneumonectomized rats. The intracellular contents of disaturated phosphatidylcholine (DSPC) and total PC, as well as the ratio of these two lipids, were the same in hypertrophic and normotrophic cells from pneumonectomized rats and in cells isolated from normal rats. No significant difference was observed in the rate at which hypertrophic or normotrophic cells incorporated choline into DSPC. These results demonstrate that type II pneumocyte hypertrophy after pneumonectomy reflects balanced cell growth secondary to cell cycle progression in vivo. The data also indicate that epithelial cell hypertrophy after pneumonectomy, in contrast to that which develops after more acute lung injury, occurs without activation of surfactant biosynthesis or storage.


1991 ◽  
Vol 261 (4) ◽  
pp. L110-L117 ◽  
Author(s):  
Bruce D. Uhal ◽  
Kevin M. Flowers ◽  
D. Eugene Rannels

In adult animals, the type II pneumocyte is progenitor of both the type I and type II alveolar epithelium. In primary culture, however, the fate of this cell is uncertain. Type II cells in culture lose their differentiated properties and eventually resemble type I cells, but a lack of specific markers has complicated the characterization of the phenotype acquired in vitro. Furthermore, limited proliferation of these cells in vitro has precluded definition of the relationship between type II cell proliferation and differentiation. Recent work in this laboratory has involved the correlation of flow cytometric cell cycle analysis with phenotype markers. Initial results indicate that isolation of type II cells induces cell cycle block similar to that sustained by other cell types in response to stress. In addition, preliminary evaluation of phenotype suggests that traditional markers become ambiguous beyond the 1st day of primary culture. These results raise concern related to the interpretation of experiments conducted in vitro. This report discusses the implications of these findings and directions for future work. alveolar epithelium; bromodeoxyuridine; cell cycle block; flow cytometry; lung injury


Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 5216-5216
Author(s):  
Laura M Desbourdes ◽  
Adam J Guess ◽  
Suheyla Hasgur ◽  
Kathleen M Overholt ◽  
Minjun Yu ◽  
...  

Abstract Introduction The 5-year survival for patients with acute myeloid leukemia (AML) has stagnated for over two decades at about 60% for children, 40% for young adults, and <15% for elderly patients. While most patients achieve remission, approximately 50% will relapse which is generally attributed to the persistence of leukemic stem cells. Interferon α (IFNα) is an effective therapy for patients with AML due to multiple mechanisms of action. However, high serum levels are associated with many adverse effects. In this proof-of-concept study, we used engineered mesenchymal stem/stromal cells (MSC) to deliver high concentrations of IFNα locally to an AML chloroma, potentially diminishing the poorly tolerated systemic side-effects. Methods Bone marrow MSCs from C57BL/6 mouse were isolated and transduced with a lentiviral vector expressing murine IFNα (IFNα-MSCs) and/or GFP (GFP MSCs). After measuring IFNα secretion by ELISA and confirming activity by the induction of the MHC I expression on the transduced cells, the anti-AML activity of these transduced MSCs was assessed by co-culture with the C57BL/6 AML cell line c1498 which expresses DsRed and firefly luciferase (FFluc). Apoptotic cell frequencies and cell cycle phase distributions of leukemia cells with or without MSCs were assessed by flow cytometry. The in vivo validation has been performed by subcutaneous injection of c1498 cells (chloroma) with or without GFP MSCs or IFNα MSCs in C57BL/6 mice. Tumor growth was monitored by bioluminescence imaging every 3 or 4 days. Results Flow cytometric analysis and ELISA confirmed the secretion of bio-active of IFNα by transduced MSCs (41.5 ng/1E06 MSCs/24h). In co-cultures, the presence of IFNα MSCs at the ratio 100:1 (c1498: MSC) significantly decreased the population of c1498 cells mainly by inducing apoptosis compared to MSC-free or GFP MSC co-cultures while no effect was observed on cell cycle distribution. The pro-apoptotic effect of IFNα MSCs was then investigated in vivo by subcutaneous injection of c1498 cells with or without MSCs (ratio 10:1) in C57BL/6 mice.The presence of IFNα MSCs significantly decreased leukemic cell mass as shown by the bioluminescence of the DsRed+ FFLuc+ c1498 cells. This result was confirmed by flow cytometric analysis of the percentage of DsRed + cells in the chloroma. Conclusions This study shows that IFNα MSCs present a strong anti-leukemic effect in vitro and in vivo promoting apoptosis and thus decreasing the leukemic burden. Further experiments will focus on a potential synergetic effect with Cytarabine treatment and a preclinical study using human IFNα MSCs in a xenograft murine model. Disclosures No relevant conflicts of interest to declare.


1991 ◽  
Vol 261 (4) ◽  
pp. 110-117 ◽  
Author(s):  
Bruce D. Uhal ◽  
Kevin M. Flowers ◽  
D. Eugene Rannels

In adult animals, the type II pneumocyte is progenitor of both the type I and type II alveolar epithelium. In primary culture, however, the fate of this cell is uncertain. Type II cells in culture lose their differentiated properties and eventually resemble type I cells, but a lack of specific markers has complicated the characterization of the phenotype acquired in vitro. Furthermore, limited proliferation of these cells in vitro has precluded definition of the relationship between type II cell proliferation and differentiation. Recent work in this laboratory has involved the correlation of flow cytometric cell cycle analysis with phenotype markers. Initial results indicate that isolation of type II cells induces cell cycle block similar to that sustained by other cell types in response to stress. In addition, preliminary evaluation of phenotype suggests that traditional markers become ambiguous beyond the 1st day of primary culture. These results raise concern related to the interpretation of experiments conducted in vitro. This report discusses the implications of these findings and directions for future work. alveolar epithelium; bromodeoxyuridine; cell cycle block; flow cytometry; lung injury


Cytometry ◽  
1991 ◽  
Vol 12 (1) ◽  
pp. 33-41 ◽  
Author(s):  
Franz Fogt ◽  
Jennifer Wan ◽  
Carl O'Hara ◽  
Bruce R. Bistrian ◽  
George L. Blackburn ◽  
...  

2019 ◽  
Vol 19 (3) ◽  
pp. 365-374 ◽  
Author(s):  
Yang Liu ◽  
Jingyin Zhang ◽  
Shuyun Feng ◽  
Tingli Zhao ◽  
Zhengzheng Li ◽  
...  

Objective: The aim of this study is to investigate the inhibitory effect of camptothecin derivative 3j on Non-Small Cell Lung Cancer (NSCLCs) cells and the potential anti-tumor mechanisms. Background: Camptothecin compounds are considered as the third largest natural drugs which are widely investigated in the world and they suffered restriction because of serious toxicity, such as hemorrhagic cystitis and bone marrow suppression. Methods: Using cell proliferation assay and S180 tumor mice model, a series of 20(S)-O-substituted benzoyl 7- ethylcamptothecin compounds were screened and evaluated the antitumor activities in vitro and in vivo. Camptothecin derivative 3j was selected for further study using flow cytometry in NSCLCs cells. Cell cycle related protein cyclin A2, CDK2, cyclin D and cyclin E were detected by Western Blot. Then, computer molecular docking was used to confirm the interaction between 3j and Topo I. Also, DNA relaxation assay and alkaline comet assay were used to investigate the mechanism of 3j on DNA damage. Results: Our results demonstrated that camptothecin derivative 3j showed a greater antitumor effect in eleven 20(S)-O-substituted benzoyl 7-ethylcamptothecin compounds in vitro and in vivo. The IC50 of 3j was 1.54± 0.41 µM lower than irinotecan with an IC50 of 13.86±0.80 µM in NCI-H460 cell, which was reduced by 8 fold. In NCI-H1975 cell, the IC50 of 3j was 1.87±0.23 µM lower than irinotecan (IC50±SD, 5.35±0.38 µM), dropped by 1.8 fold. Flow cytometry analysis revealed that 3j induced significant accumulation in a dose-dependent manner. After 24h of 3j (10 µM) treatment, the percentage of NCI-H460 cell in S-phase significantly increased (to 93.54 ± 4.4%) compared with control cells (31.67 ± 3.4%). Similarly, the percentage of NCI-H1975 cell in Sphase significantly increased (to 83.99 ± 2.4%) compared with control cells (34.45 ± 3.9%) after treatment with 10µM of 3j. Moreover, increased levels of cyclin A2, CDK2, and decreased levels of cyclin D, cyclin E further confirmed that cell cycle arrest was induced by 3j. Furthermore, molecular docking studies suggested that 3j interacted with Topo I-DNA and DNA-relaxation assay simultaneously confirmed that 3j suppressed the activity of Topo I. Research on the mechanism showed that 3j exhibited anti-tumour activity via activating the DNA damage response pathway and suppressing the repair pathway in NSCLC cells. Conclusion: Novel camptothecin derivative 3j has been demonstrated as a promising antitumor agent and remains to be assessed in further studies.


2006 ◽  
Vol 26 (3) ◽  
pp. 965-975 ◽  
Author(s):  
Tom S. Kim ◽  
Cynthia Heinlein ◽  
Robert C. Hackman ◽  
Peter S. Nelson

ABSTRACT Tmprss2 encodes an androgen-regulated type II transmembrane serine protease (TTSP) expressed highly in normal prostate epithelium and has been implicated in prostate carcinogenesis. Although in vitro studies suggest protease-activated receptor 2 may be a substrate for TMPRSS2, the in vivo biological activities of TMPRSS2 remain unknown. We generated Tmprss2 −/− mice by disrupting the serine protease domain through homologous recombination. Compared to wild-type littermates, Tmprss2 −/− mice developed normally, survived to adulthood with no differences in protein levels of prostatic secretions, and exhibited no discernible abnormalities in organ histology or function. Loss of TMPRSS2 serine protease activity did not influence fertility, reduce survival, result in prostate hyperplasia or carcinoma, or alter prostatic luminal epithelial cell regrowth following castration and androgen replacement. Lack of an observable phenotype in Tmprss2 −/− mice was not due to transcriptional compensation by closely related Tmprss2 homologs. We conclude that the lack of a discernible phenotype in Tmprss2 −/− mice suggests functional redundancy involving one or more of the type II transmembrane serine protease family members or other serine proteases. Alternatively, TMPRSS2 may contribute a specialized but nonvital function that is apparent only in the context of stress, disease, or other systemic perturbation.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Shuiyan Wu ◽  
You Jiang ◽  
Yi Hong ◽  
Xinran Chu ◽  
Zimu Zhang ◽  
...  

Abstract Background T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive disease with a high risk of induction failure and poor outcomes, with relapse due to drug resistance. Recent studies show that bromodomains and extra-terminal (BET) protein inhibitors are promising anti-cancer agents. ARV-825, comprising a BET inhibitor conjugated with cereblon ligand, was recently developed to attenuate the growth of multiple tumors in vitro and in vivo. However, the functional and molecular mechanisms of ARV-825 in T-ALL remain unclear. This study aimed to investigate the therapeutic efficacy and potential mechanism of ARV-825 in T-ALL. Methods Expression of the BRD4 were determined in pediatric T-ALL samples and differential gene expression after ARV-825 treatment was explored by RNA-seq and quantitative reverse transcription-polymerase chain reaction. T-ALL cell viability was measured by CCK8 assay after ARV-825 administration. Cell cycle was analyzed by propidium iodide (PI) staining and apoptosis was assessed by Annexin V/PI staining. BRD4, BRD3 and BRD2 proteins were detected by western blot in cells treated with ARV-825. The effect of ARV-825 on T-ALL cells was analyzed in vivo. The functional and molecular pathways involved in ARV-825 treatment of T-ALL were verified by western blot and chromatin immunoprecipitation (ChIP). Results BRD4 expression was higher in pediatric T-ALL samples compared with T-cells from healthy donors. High BRD4 expression indicated a poor outcome. ARV-825 suppressed cell proliferation in vitro by arresting the cell cycle and inducing apoptosis, with elevated poly-ADP ribose polymerase and cleaved caspase 3. BRD4, BRD3, and BRD2 were degraded in line with reduced cereblon expression in T-ALL cells. ARV-825 had a lower IC50 in T-ALL cells compared with JQ1, dBET1 and OTX015. ARV-825 perturbed the H3K27Ac-Myc pathway and reduced c-Myc protein levels in T-ALL cells according to RNA-seq and ChIP. In the T-ALL xenograft model, ARV-825 significantly reduced tumor growth and led to the dysregulation of Ki67 and cleaved caspase 3. Moreover, ARV-825 inhibited cell proliferation by depleting BET and c-Myc proteins in vitro and in vivo. Conclusions BRD4 indicates a poor prognosis in T-ALL. The BRD4 degrader ARV-825 can effectively suppress the proliferation and promote apoptosis of T-ALL cells via BET protein depletion and c-Myc inhibition, thus providing a new strategy for the treatment of T-ALL.


2021 ◽  
Vol 26 (1) ◽  
Author(s):  
Guoying Zhang ◽  
Cheng Xue ◽  
Yiming Zeng

Abstract Background We have previously found that β-elemene could inhibit the viability of airway granulation fibroblasts and prevent airway hyperplastic stenosis. This study aimed to elucidate the underlying mechanism and protective efficacy of β-elemene in vitro and in vivo. Methods Microarray and bioinformatic analysis were used to identify altered pathways related to cell viability in a β-elemene-treated primary cell model and to construct a β-elemene-altered ceRNA network modulating the target pathway. Loss of function and gain of function approaches were performed to examine the role of the ceRNA axis in β-elemene's regulation of the target pathway and cell viability. Additionally, in a β-elemene-treated rabbit model of airway stenosis, endoscopic and histological examinations were used to evaluate its therapeutic efficacy and further verify its mechanism of action. Results The hyperactive ILK/Akt pathway and dysregulated LncRNA-MIR143HG, which acted as a miR-1275 ceRNA to modulate ILK expression, were suppressed in β-elemene-treated airway granulation fibroblasts; β-elemene suppressed the ILK/Akt pathway via the MIR143HG/miR-1275/ILK axis. Additionally, the cell cycle and apoptotic phenotypes of granulation fibroblasts were altered, consistent with ILK/Akt pathway activity. In vivo application of β-elemene attenuated airway granulation hyperplasia and alleviated scar stricture, and histological detections suggested that β-elemene's effects on the MIR143HG/miR-1275/ILK axis and ILK/Akt pathway were in line with in vitro findings. Conclusions MIR143HG and ILK may act as ceRNA to sponge miR-1275. The MIR143HG/miR-1275/ILK axis mediates β-elemene-induced cell cycle arrest and apoptosis of airway granulation fibroblasts by modulating the ILK/Akt pathway, thereby inhibiting airway granulation proliferation and ultimately alleviating airway stenosis.


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