scholarly journals In Vitro and In Vivo Phagocytic Ability of Mouse B-1 Cells

2010 ◽  
Vol 2 ◽  
pp. III.S6156 ◽  
Author(s):  
RR Novaes E Brito ◽  
BA Cortez ◽  
GM Machado-Santelli ◽  
P Xander ◽  
BH De Lorenzo ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
B Cells ◽  
Peritoneal Cavity ◽  
Mononuclear Phagocyte ◽  
Phagocytic Cells ◽  
Phagocytic Ability ◽  
Escherichia Coli Bacteria ◽  
Pathogen Clearance

B-1 cells are a peculiar subpopulation of B cells found in the peritoneal and pleural cavities in mice. These cells are typically IgM+ and CD11b+. B-1 cells are able to migrate from the peritoneal cavity to non-specific inflammatory sites in mice. In addition, they can differentiate into mononuclear phagocyte-like cells in vitro; however, it is still unknown whether B-1 cells are capable of performing phagocytosis in vivo. Here we further characterized B-1 cells as phagocytes in vitro, and we investigated their ability to phagocytose apoptotic cells and bacteria in vivo. Our results demonstrate that B-1 phagocytes are able to uptake apoptotic thymocytes and Escherichia coli bacteria, both in vitro and in vivo. These findings indicate that along with macrophages, B-1 phagocytic cells might play a role in fundamental processes such as tissue remodeling, resolution of inflammation and pathogen clearance.

Fate of the fish pathogen Aeromonas salmonicida in the peritoneal cavity of rainbow trout

1993 ◽  
Vol 39 (11) ◽  
pp. 1051-1058 ◽  
Author(s):  
Rafael A. Garduño ◽  
Julian C. Thornton ◽  
William W. Kay
Keyword(s):  
Rainbow Trout ◽  
Peritoneal Cavity ◽  
Peritoneal Fluid ◽  
Aeromonas Salmonicida ◽  
Lytic Activity ◽  
Fish Pathogen ◽  
Phagocytic Cells ◽  
Fish Pathogens

A model was developed to study the fate of the fish pathogen Aeromonas salmonicida in vivo, inside a specialized intraperitoneal chamber implanted in rainbow trout, Oncorhynchus mykiss. Although normally recalcitrant to lytic agents in vitro, owing to the presence of its regular surface array (S layer), A. salmonicida was rapidly killed in the peritoneal cavity by a host-derived, soluble lytic activity present in peritoneal fluid. Peritoneal fluid was also found to kill other bacteria and lyse various types of erythrocytes, but was particularly lytic to A. salmonicida. Intraperitoneal survival of injected (free) A. salmonicida cells was several orders of magnitude higher than survival of implanted (restrained) cells. Injected free cells could evade the lytic activity of peritoneal fluid because they readily spread, initiating lethal infections. One evasion strategy was envisioned to be the penetration of peritoneal and (or) tissue macrophages. In spite of the killing mechanisms of these phagocytic cells, A. salmonicida was still able to survive and even replicate inside head kidney macrophages, thereby supporting the notion of A. salmonicida as a facultatively intracellular pathogen. Intraperitoneal chambers in rainbow trout may constitute a valuable experimental tool for studying the in vivo fate of A. salmonicida, and perhaps of other fish pathogens as well.Key words: Aeromonas salmonicida, intraperitoneal chambers, rainbow trout, complement-mediated cell lysis.

Безопасность соединений из группы терпенов ментанового ряда in vitro и in vivo

2020 ◽  
Vol 83 (4) ◽  
pp. 24-30
Author(s):  
Ирина Владимировна Акулина ◽  
Светлана Ивановна Павлова ◽  
Ирина Семеновна Степаненко ◽  
Назира Сунагатовна Карамова ◽  
Александр Владиславович Сергеев ◽  
...  
Keyword(s):  
Escherichia Coli

Проведено токсикологическое исследование соединений с антибактериальными свойствами из группы терпенов ментанового ряда в условиях in vitro и in vivo: лимонена (B34), его производного (+)-1,2-оксида лимонена (B60) и серосодержащего монотерпенового соединения 2-(1’-гидрокси-4’-изопренил-1’-метилциклогексил-2’-тио)метилэтаноата (B65). В условиях in vitro (культура опухолевых клеток HeLa) изучаемые монотерпены в диапазоне концентраций 2 – 200 мкг/мл обладали цитотоксичностью. Ингибирующая концентрация (ИК50) для B34 составила 231 (167 – 295) мкг/мл, для B60 – 181 (105 – 257) мкг/мл, ИК50 B65 – 229 (150 – 308) мкг/мл. Исследование генотоксичности показало, что B34 и B65 в диапазоне концентраций 50 – 1000 мкг/мл не индуцируют SOS мутагенез в клетках Escherichia coli PQ37, тогда как B60 в концентрациях 500 и 1000 мкг/мл проявляет генотоксичность. In vivo в остром эксперименте на беспородных мышах установлена низкая токсичность B34 и его производных при различных путях введения. Наименьший показатель острой токсичности имеет B65, в связи с чем дополнительно на крысах проведено изучение его хронической токсичности. Ежедневное внутрижелудочное введение B65 в разовых дозах, составляющих 1/10 и 1/20 ЛД50 (1000 мг/кг и 500 мг/кг), в течение 1 мес не вызывало гибели животных, значимых нарушений общего состояния, изменения динамики массы тела, морфопатологических изменений. Внутрижелудочное введение B65 крысам в высокой токсической дозе 2000 мг/кг (1/5 ЛД50) в течение месяца вызывает патоморфологические изменения структуры печени.

Ginkgolic acid induces apoptosis and autophagy of endometrial carcinoma cells via inhibiting PI3K/Akt/mTOR pathway in vivo and in vitro

2021 ◽  
pp. 096032712110237
Author(s):  
L Zhou ◽  
S Li ◽  
J Sun
Keyword(s):  
Endometrial Cancer ◽  
B Cells ◽  
Western Blot ◽  
Signal Pathway ◽  
Mtor Pathway ◽  
Related Protein ◽  
Western Blot Assay ◽  
Ginkgolic Acid

Endometrial cancer (EC) is the fourth most common malignancy in women in developed countries. The prognosis of EC is extremely poor, and it is an important factor that contributes to the death of patients. Therefore, studying EC pathogenesis and therapeutic targets, and exploring effective drugs are the primary tasks to improve the prognosis of EC. In the present study, we aimed to explore the function of ginkgolic acid (GA) in EC cell apoptosis and autophagy through PI3K/Akt/mTOR signal pathway in vitro and in vivo. Firstly, MTT assay and clone formation assay were employed to analyze the Ishikawa and HEC-1-B cell viabilities and proliferation after treatment with GA. The results showed that GA inhibited endometrial cancer cell survival. Flow cytometry assay and western blot assay were applied to examine the apoptosis and apoptosis related protein Bcl-2, Bax, Cleaved caspase-3 expression levels of Ishikawa and HEC-1-B cells after treatment with GA. Next, we applied western blot assay to analyze the autophagy associated proteins LC3I, LC3II, p62 and Beclin-1 in GA treated Ishikawa and HEC-1-B cells. We found that GA promoted apoptosis and induced autophagy of endometrial cancer cells. Meanwhile, western blot assay was also used to determine the expression levels of the PI3K/Akt/mTOR signal pathway related protein and the results revealed that GA inhibited the activity of PI3K/Akt/mTOR pathway. Finally, we found that GA inhibited tumor growth in vivo through immunohistochemistry assay. In conclusion, GA induces apoptosis and autophagy of EC cells via inhibiting PI3K/Akt/mTOR pathway in vivo and vitro.

scholarly journals Antagonism of Ultraviolet-Light Mutagenesis by the Methyl-Directed Mismatch-Repair System of Escherichia coli

Genetics ◽  
2000 ◽  
Vol 154 (2) ◽  
pp. 503-512 ◽  
Author(s):  
Hongbo Liu ◽  
Stephen R Hewitt ◽  
John B Hays
Keyword(s):  
Escherichia Coli ◽  
Mismatch Repair ◽  
Excision Repair ◽  
Spontaneous Mutation ◽  
Repair System ◽  
Uv Mutagenesis ◽  
Repair Protein ◽  
Mismatch Repair System

Abstract Previous studies have demonstrated that the Escherichia coli MutHLS mismatch-repair system can process UV-irradiated DNA in vivo and that the human MSH2·MSH6 mismatch-repair protein binds more strongly in vitro to photoproduct/base mismatches than to “matched” photoproducts in DNA. We tested the hypothesis that mismatch repair directed against incorrect bases opposite photoproducts might reduce UV mutagenesis, using two alleles at E. coli lacZ codon 461, which revert, respectively, via CCC → CTC and CTT → CTC transitions. F′ lacZ targets were mated from mut+ donors into mutH, mutL, or mutS recipients, once cells were at substantial densities, to minimize spontaneous mutation prior to irradiation. In umu+ mut+ recipients, a range of UV fluences induced lac+ revertant frequencies of 4–25 × 10−8; these frequencies were consistently 2-fold higher in mutH, mutL, or mutS recipients. Since this effect on mutation frequency was unaltered by an Mfd− defect, it appears not to involve transcription-coupled excision repair. In mut+ umuC122::Tn5 bacteria, UV mutagenesis (at 60 J/m2) was very low, but mutH or mutL or mutS mutations increased reversion of both lacZ alleles roughly 25-fold, to 5–10 × 10−8. Thus, at UV doses too low to induce SOS functions, such as Umu2′D, most incorrect bases opposite occasional photoproducts may be removed by mismatch repair, whereas in heavily irradiated (SOS-induced) cells, mismatch repair may only correct some photoproduct/base mismatches, so UV mutagenesis remains substantial.

Exploring Galleria mellonella larval model to evaluate antibacterial efficacy of Cecropin A (1-7)- Melittin against multi-drug resistant enteroaggregative Escherichia coli

2021 ◽  
Author(s):  
Jess Vergis ◽  
S V S Malik ◽  
Richa Pathak ◽  
Manesh Kumar ◽  
Nitin V Kurkure ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Galleria Mellonella ◽  
In Vivo Model ◽  
Drug Resistant ◽  
Physiological Concentration ◽  
Microbial Drug Resistance ◽  
Cecropin A ◽  
Screening And Identification

Abstract High throughput in vivo laboratory models is need for screening and identification of effective therapeutic agents to overcome microbial drug-resistance. This study was undertaken to evaluate in vivo antimicrobial efficacy of short-chain antimicrobial peptide- Cecropin A (1–7)-Melittin (CAMA) against three multi- drug resistant enteroaggregative Escherichia coli (MDR-EAEC) field isolates in a Galleria mellonella larval model. The minimum inhibitory concentration (MIC; 2.0 mg/L) and minimum bactericidal concentration (MBC; 4.0 mg/L) of CAMA were determined by microdilution assay. CAMA was found to be stable at high temperatures, physiological concentration of cationic salts and proteases; safe with sheep erythrocytes, secondary cell lines and commensal lactobacilli at lower MICs; and exhibited membrane permeabilisation. In vitro time-kill assay revealed concentration- and time-dependent clearance of MDR-EAEC in CAMA-treated groups at 30 min. CAMA- treated G. mellonella larvae exhibited an increased survival rate, reduced MDR-EAEC counts, immunomodulatory effect and proved non-toxic which concurred with histopathological findings. CAMA exhibited either an equal or better efficacy than the tested antibiotic control, meropenem. This study highlights the possibility of G. mellonella larvae as an excellent in vivo model for investigating the host-pathogen interaction, including the efficacy of antimicrobials against MDR-EAEC strains.

scholarly journals Immunocompatibility of a new dual modality contrast agent based on radiolabeled iron-oxide nanoparticles

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Maria-Argyro Karageorgou ◽  
Dimosthenis Stamopoulos
Keyword(s):  
Complete Blood Count ◽  
Morphological Characteristics ◽  
Mononuclear Phagocyte ◽  
Dual Modality ◽  
Immunodeficient Mice ◽  
Force Microscopy ◽  
Magnetic Resonance Imaging Mri ◽  
Diagnostic Applications

AbstractRadiolabeled magnetic nanoparticles are promising candidates as dual-modality-contrast-agents (DMCA) for diagnostic applications. The immunocompatibility of a new DMCA is a prerequisite for subsequent in vivo applications. Here, a new DMCA, namely Fe3O4 nanoparticles radiolabeled with 68Ga, is subjected to immunocompatibility tests both in vitro and in vivo. The in vitro immunocompatibility of the DMCA relied on incubation with donated human WBCs and PLTs (five healthy individuals). Optical microscopy (OM) and atomic force microscopy (AFM) were employed for the investigation of the morphological characteristics of WBCs and PLTs. A standard hematology analyzer (HA) provided information on complete blood count. The in vivo immunocompatibility of the DMCA was assessed through its biodistribution among the basic organs of the mononuclear phagocyte system in normal and immunodeficient mice (nine in each group). In addition, Magnetic Resonance Imaging (MRI) data were acquired in normal mice (three). The combined OM, AFM and HA in vitro data showed that although the DMCA promoted noticeable activation of WBCs and PLTs, neither degradation nor clustering were observed. The in vivo data showed no difference of the DMCA biodistribution between the normal and immunodeficient mice, while the MRI data prove the efficacy of the particular DMCA when compared to the non-radiolabeled, parent CA. The combined in vitro and in vivo data prove that the particular DMCA is a promising candidate for future in vivo applications.

scholarly journals Stronger In Vitro Phagocytosis by Monocytes-Macrophages Is Indicative of Greater Pathogen Clearance and Antibody Levels In Vivo

2008 ◽  
Vol 87 (9) ◽  
pp. 1725-1733 ◽  
Author(s):  
S.F. Sun ◽  
Q.Z. Pan ◽  
X. Hui ◽  
B.L. Zhang ◽  
H.M. Wu ◽  
...  
Keyword(s):  
Antibody Levels ◽  
Pathogen Clearance

scholarly journals Lysyl-tRNA synthetase from Escherichia coli K12. Chromatographic heterogeneity and the lysU-gene product

1987 ◽  
Vol 248 (1) ◽  
pp. 43-51 ◽  
Author(s):  
J Charlier ◽  
R Sanchez
Keyword(s):  
Escherichia Coli ◽  
Gene Product ◽  
Activity Ratio ◽  
Deae Cellulose ◽  
Trna Synthetase ◽  
Trna Synthetases ◽  
E Coli ◽  
Aminoacyl Trna Synthetases

In contrast with most aminoacyl-tRNA synthetases, the lysyl-tRNA synthetase of Escherichia coli is coded for by two genes, the normal lysS gene and the inducible lysU gene. During its purification from E. coli K12, lysyl-tRNA synthetase was monitored by its aminoacylation and adenosine(5′)tetraphospho(5′)adenosine (Ap4A) synthesis activities. Ap4A synthesis was measured by a new assay using DEAE-cellulose filters. The heterogeneity of lysyl-tRNA synthetase (LysRS) was revealed on hydroxyapatite; we focused on the first peak, LysRS1, because of its higher Ap4A/lysyl-tRNA activity ratio at that stage. Additional differences between LysRS1 and LysRS2 (major peak on hydroxyapatite) were collected. LysRS1 was eluted from phosphocellulose in the presence of the substrates, whereas LysRS2 was not. Phosphocellulose chromatography was used to show the increase of LysRS1 in cells submitted to heat shock. Also, the Mg2+ optimum in the Ap4A-synthesis reaction is much higher for LysRS1. LysRS1 showed a higher thermostability, which was specifically enhanced by Zn2+. These results in vivo and in vitro strongly suggest that LysRS1 is the heat-inducible lysU-gene product.

Sign in / Sign up

Export Citation Format

Share Document