scholarly journals ROLE OF SUGARS IN SURFACE MICROBE-HOST INTERACTIONS IN GROUP B STREPTOCOCCUS INVASION

2020 ◽  
pp. 54-58
Author(s):  
MANJU O PAI ◽  
VENKATESH S ◽  
PRATIMA GUPTA ◽  
ANURADHA CHAKRABORTI
Keyword(s):  
Cell Lines ◽  
Group B Streptococcus ◽  
A549 Cells ◽  
Alternative Therapies ◽  
Host Interactions ◽  
Specific Receptors ◽  
Group B ◽  
Sizeable Reduction

Objective: Metabolic sources for food play a very important role in developing a niche for a microbe to invade and cause infection in the host. The influence of various sugars on invasion of Streptococcus agalactiae or Group B streptococcus (GBS) into HeLa and A549 cells in vitro were evaluated. Methods: The cell lines and the bacteria were pretreated separately with different sugars before invasion. These observations were also corroborated with light microscopy. Results: Our results showed that the maximum GBS invasion observed at 2h, decreased significantly (p<0.05) when the cells were pretreated with N-acetyl galactosamine (GlcNAc), D-xylose, sucrose, lactose, D-mannose, and D-glucose. In contrast, mannitol was seen to support the invasion of GBS. In addition, when a combined effect of GlcNAc and xylose was studied, 87.5%–91% inhibition to GBS invasion was observed in HeLa and A549 cell lines, respectively. A sizeable reduction in invasion was observed when the bacteria were pretreated with 10 mM of D-Glucose (79.32%), GlcNAc (69.66%), and mannose (48.28%). In conclusion, GlcNAc, D-xylose, and D-glucose proved to be excellent inhibitors to GBS invasion. Furthermore, bacterial pretreatment results might indicate that these sugar specific receptors might be present on the epithelial cells which possibly gets blocked and thus inhibits the entry of GBS. Conclusion: These findings are the first to suggest the role of these sugars as a way to alternative therapies to GBS infection by altering the host-pathogen environment during invasion.

Group B Streptococcal and Pneumococcal Sepsis in Newborn Infants: The Role of Pneumococcal Antibody

PEDIATRICS ◽  
1978 ◽  
Vol 62 (4) ◽  
pp. 620-621
Author(s):  
Gerald W. Fischer ◽  
James W. Bass ◽  
George H. Lowell ◽  
Martin H. Crumrine
Keyword(s):  
Streptococcus Pneumoniae ◽  
Hydrochloric Acid ◽  
Group B Streptococcus ◽  
Newborn Infants ◽  
Polysaccharide Antigen ◽  
Type Iii ◽  
Pneumococcal Sepsis ◽  
Group B

The article by Bortolussi et al. on pneumococcal septicemia and meningitis in the neonat (Pediatrics 60:352, September 1977) was of great interest to us, since we have been analyzing the effect of antibody directed against Streptococcus pneumoniae on group B Streptococcus type III. We have recently shown (unpublished data) that antibody directed against S. pneumoniae type 14 precipitates the hot hydrochloric acid-extracted polysaccharide antigen of group B Streptococcus type III. Further studies have shown that this antibody is opsonic for group B Streptococcus type III in an in vitro bactericidal assay and protective in a suckling rat model of group B Streptococcus type III sepsis.1

scholarly journals Adherence to, Invasion by, and Cytokine Production in Response to Serotype VIII Group B Streptococci

2004 ◽  
Vol 72 (8) ◽  
pp. 4716-4722 ◽  
Author(s):  
Hiroshige Mikamo ◽  
Atul K. Johri ◽  
Lawrence C. Paoletti ◽  
Lawrence C. Madoff ◽  
Andrew B. Onderdonk
Keyword(s):  
Cytokine Production ◽  
Group B Streptococcus ◽  
A549 Cells ◽  
Interleukin 10 ◽  
Epithelial Cell Line ◽  
Group B Streptococci ◽  
Necrosis Factor Alpha ◽  
Tnf Α ◽  
Group B

ABSTRACT The adherence to and invasion of the human epithelial cell line A549 by group B streptococcus (GBS) serotype VIII strains were compared with those of serotype III strains by a conventional method and the dynamic in vitro attachment and invasion system. Twenty GBS strains, including nine vaginal isolates and one invasive isolate each of serotypes III and VIII, were used in the conventional attachment and invasion assay. Adherence to and invasion of A549 cells by serotype VIII GBS strains were significantly greater (P < 0.0001) than those by serotype III strains for both the invasive strain and vaginal isolates. Cytokine production by A549 cells following stimulation with GBS serotypes III and VIII or their purified capsular polysaccharides (CPS) was measured. Serotype III strains stimulated significantly greater tumor necrosis factor alpha (TNF-α) (P < 0.0001) and interleukin-10 (IL-10) (P < 0.05) production than did serotype VIII strains. IL-8 production in response to serotype VIII was significantly higher (P < 0.001) than that in response to serotype III. TNF-α, IL-8, and IL-10 production was greater in A549 cells infected with GBS than in the untreated control cells. TNF-α production was significantly greater (P < 0.005) after stimulation with purified GBS serotype III CPS than after stimulation with serotype VIII CPS, a result similar to that after stimulation with whole GBS. IL-12 production by A549 cells was observed only in response to infection with GBS serotype III, resulting in the possibility of a greater TH1 response in serotype III GBS. These results suggest differences in immune responses to infection with GBS serotypes III and VIII.

Synthesis and Cytotoxicity Assessment of Novel 7-O- and 14-O-Derivatives of Glaucocalyxin A

2020 ◽  
Vol 20 (10) ◽  
pp. 1241-1249
Author(s):  
Hong-Chuan Liu ◽  
Li-Ming Qiao ◽  
Wei Zheng ◽  
Zhao-Bao Xiang ◽  
Hai-Sheng Chen ◽  
...  
Keyword(s):  
Acute Toxicity ◽  
Cell Lines ◽  
Cancer Cell ◽  
Human Cancer ◽  
Folk Medicine ◽  
A549 Cells ◽  
Cancer Cell Lines ◽  
Human Cancer Cell Lines ◽  
Derivatives Of

Background: Rabdosia japonica has been historically used in China as a popular folk medicine for the treatment of cancer, hepatitis, and gastricism. Glaucocalyxin A (GLA), an ent-kaurene diterpene isolated from Rabdosia japonica, is one of the main active ingredients showing potent inhibitory effects against several types of tumor cells. To the best of our knowledge, studies regarding the structural modification and Structure- Activity Relations (SAR) of this compound have not yet been reported. Objective: The aim of this study was to discover more potent derivatives of GLA and investigate their SAR and cytotoxicity mechanisms. Methods: Novel 7-O- and 14-O-derivatives of GLA were synthesized by condensation of acids or acyl chloride. The anti-tumor activities of these derivatives against various human cancer cell lines were evaluated in vitro by MTT assays. Apoptosis assays of compound 17 (7,14-diacylation product) were performed on A549 and HL-60 cells by flow cytometry and TUNNEL. The acute toxicity of this compound was tested on mice, at the dose of 300mg per kg body weight. Results: Seventeen novel 7-O- and 14-O-derivatives of GLA (1-17) were synthesized. These compounds showed potent cytotoxicity against the tested cancer cell lines, and almost all of them were found to be more cytotoxic than GLA and oridonin. Of the synthesized derivatives, compound 17 presented the greatest cytotoxicity, with IC50 values of 0.26μM and 1.10μM in HL-60 and CCRF-CEM cells, respectively. Furthermore, this compound induced weak apoptosis of A549 cells but showed great potential in stimulating the apoptosis of HL- 60 cells. Acute toxicity assays indicated that compound 17 is relatively safer. Conclusion: The results reported herein indicate that the synthesized GLA derivatives exhibited greater cytotoxicity against leukemia cells than against other types of tumors. In particular, 7,14-diacylation product of GLA was found to be an effective anti-tumor agent. However, the cytotoxicity mechanism of this product in A549 cells is expected to be different than that in other tumor cell lines. Further research is needed to confirm this hypothesis.

scholarly journals Hsa_circ_0005273 facilitates breast cancer tumorigenesis by regulating YAP1-hippo signaling pathway

2021 ◽  
Vol 40 (1) ◽  
Author(s):  
Xuehui Wang ◽  
Changle Ji ◽  
Jiashu Hu ◽  
Xiaochong Deng ◽  
Wenfang Zheng ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Signaling Pathway ◽  
Cell Lines ◽  
Luciferase Reporter ◽  
Circular Rnas ◽  
Hippo Signaling ◽  
Hippo Signaling Pathway ◽  
Potential Biomarker

Abstract Background Circular RNAs (circRNAs), a novel class of endogenous RNAs, have shown to participate in the development of breast cancer (BC). Hsa_circ_0005273 is a circRNA generated from several exons of PTK2. However, the potential functional role of hsa_circ_0005273 in BC remains largely unknown. Here we aim to evaluate the role of hsa_circ_0005273 in BC. Methods The expression level of hsa_circ_0005273 and miR-200a-3p were examined by RT-qPCR in BC tissues and cell lines. The effect of knocking down hsa_circ_0005273 in BC cell lines were evaluated by examinations of cell proliferation, migration and cell cycle. In addition, xenografts experiment in nude mice were performed to evaluate the effect of hsa_circ_0005273 in BC. RNA immunoprecipitation assay, RNA probe pull-down assay, luciferase reporter assay and fluorescence in situ hybridization were conducted to confirm the relationship between hsa_circ_0005273, miR-200a-3p and YAP1. Results Hsa_circ_0005273 is over-expressed in BC tissues and cell lines, whereas miR-200a-3p expression is repressed. Depletion of hsa_circ_0005273 inhibited the progression of BC cells in vitro and in vivo, while overexpression of hsa_circ_0005273 exhibited the opposite effect. Importantly, hsa_circ_0005273 upregulated YAP1 expression and inactivated Hippo pathway via sponging miR-200a-3p to promote BC progression. Conclusions Hsa_circ_0005273 regulates the miR-200a-3p/YAP1 axis and inactivates Hippo signaling pathway to promote BC progression, which may become a potential biomarker and therapeutic target.

scholarly journals Progression and Differentiation of Alveolar Rhabdomyosarcoma Is Regulated by PAX7 Transcription Factor—Significance of Tumor Subclones

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1870
Author(s):  
Klaudia Skrzypek ◽  
Grażyna Adamek ◽  
Marta Kot ◽  
Bogna Badyra ◽  
Marcin Majka
Keyword(s):  
Transcription Factor ◽  
Cell Lines ◽  
Migration Activity ◽  
Id Proteins ◽  
Rh30 Cell ◽  
Str Profile ◽  
And Migration

Rhabdomyosarcoma (RMS), is the most frequent soft tissue tumor in children that originates from disturbances in differentiation process. Mechanisms leading to the development of RMS are still poorly understood. Therefore, by analysis of two RMS RH30 cell line subclones, one subclone PAX7 negative, while the second one PAX7 positive, and comparison with other RMS cell lines we aimed at identifying new mechanisms crucial for RMS progression. RH30 subclones were characterized by the same STR profile, but different morphology, rate of proliferation, migration activity and chemotactic abilities in vitro, as well as differences in tumor morphology and growth in vivo. Our analysis indicated a different level of expression of adhesion molecules (e.g., from VLA and ICAM families), myogenic microRNAs, such as miR-206 and transcription factors, such as MYOD, MYOG, SIX1, and ID. Silencing of PAX7 transcription factor with siRNA confirmed the crucial role of PAX7 transcription factor in proliferation, differentiation and migration of RMS cells. To conclude, our results suggest that tumor cell lines with the same STR profile can produce subclones that differ in many features and indicate crucial roles of PAX7 and ID proteins in the development of RMS.

Steroid Formation in Osteoblast-Like Cells

1998 ◽  
Vol 26 (1) ◽  
pp. 1-12 ◽  
Author(s):  
H Saito ◽  
T Yanaihara
Keyword(s):  
Cell Lines ◽  
Messenger Ribonucleic Acid ◽  
Steroid Sulphatase ◽  
Menopausal Women ◽  
Hormonal Action ◽  
Polymerase Chain ◽  
Post Menopausal ◽  
Receptor Mrnas

For preventing the reduction of bone mass in post-menopausal women, oestrogen replacement is known to be useful and the importance of sex steroids in bone metabolism in both sexes is well established. The presence of steroid-converting-enzyme activities in various osteoblast and osteoblast-like cells has been demonstrated using in vitro culture systems. In the present study, we assessed the expression of messenger ribonucleic acid (mRNA) for aromatase, steroid sulphatase, 5α-reductase, 17β-hydroxysteroid dehydrogenase (17β-HSD) and 3β-HSD by reverse transcription-polymerase chain reaction in the human osteoblast-like cell lines, MG 63 and HOS. Oestrogen, androgen and progesterone receptor mRNAs were also measured. Expression of mRNA for these enzymes and receptors was found in both cell lines without induction. From these and previous findings, we conclude that osteoblast-like cells have the capacity to form biologically potent oestrogens and androgens from peripheral circulating steroids. This may indicate an important role of bone in facilitating hormonal action.

Synthesis and Biological Evaluation of Novel 4-Phenylaminobenzofuro[2,3-d]pyrimidine Derivatives

2020 ◽  
Vol 42 (4) ◽  
pp. 564-564
Author(s):  
Ju liu Ju liu ◽  
Jun Li Jun Li ◽  
Jian tao Shi Jian tao Shi ◽  
Jie Li Jie Li ◽  
Xue chen Hao Xue chen Hao ◽  
...  
Keyword(s):  
Cell Lines ◽  
A549 Cells ◽  
Positive Control ◽  
Biological Evaluation ◽  
Dependent Manner ◽  
Pyrimidine Derivatives ◽  
Concentration Dependent Manner ◽  
Ic50 Value ◽  
Synthesis And Biological Evaluation

A series of novel 4-phenylaminobenzofuro[2,3-d]pyrimidine derivatives had been prepared and assessed for their in vitro antiproliferative activities against three lung cancer cell lines (A549, H460 and H1975). The bioassay results showed most of the designed compounds exhibited potential antiproliferation activities. Among them, compound 8f exhibited remarkable inhibitory activity against A549 and H460 cell lines with IC50 value of 2.54 μM and 2.68 μM, respectively, which was comparable to that of the positive control sorafenib (IC50 = 2.69 μM for A549 and 3.71 μM for H460). AO/EB staining suggests that compound 8f could induce apoptosis in A549 cells. Furthermore, cell cycle analyses show that compound 8f increased G0/G1 A549 cells arrest in a concentration-dependent manner. The preliminary structure-activity relationships (SARs) studies indicated that mono-electron-withdrawing groups (mono-EWGs) on the phenyl ring are positive on the antitumor activity.

Human Immunoglobulins for Intravenous Use: Comparison of Available Preparations for Group B Streptococcal Antibody Levels, Opsonic Activity, and Efficacy in Animal Models

PEDIATRICS ◽  
1990 ◽  
Vol 86 (6) ◽  
pp. 955-962
Author(s):  
Laurence B. Givner
Keyword(s):  
Animal Models ◽  
Neonatal Sepsis ◽  
Protective Efficacy ◽  
Group B Streptococcus ◽  
Igg Antibody ◽  
Opsonic Activity ◽  
Immunoglobulin Preparations ◽  
Group B ◽  
Antibody Levels

Currently available human immunoglobulin preparations for intravenous use (IVIGs) are being used (with antibiotics) by some physicians for therapy of sepsis in newborns. Most neonatal sepsis and/or meningitis in this country is caused by group B Streptococcus (GBS), and most of these cases are due to type III GBS (III-GBS). The killing of III-GBS in vitro is dependent on specific IgG antibody. Adequate serum levels of specific III-GBS antibody protect the exposed newborn from the development of invasive disease. Therefore, III-GBS was used as a model to evaluate the activity of three IVIG preparations available for clinical use. Specific antibody levels, in vitro opsonophagocytic killing, and protective efficacy in animal models revealed differences in activity for III-GBS between the three IVIG preparations as well as between IVIG lots from the same manufacturer. Furthermore, it was found that the effect of IVIG using one of the assay methods may not reliably predict activity obtained using the other assays. These data document the inability to predict functional activity against a specific pathogen such as GBS on the part of a lot of IVIG chosen at random. In view of these findings and of the limited data evaluating clinical efficacy, IVIG cannot be recommended at this time for use in the therapy of infectious diseases such as neonatal sepsis.

Sign in / Sign up

Export Citation Format

Share Document