scholarly journals Three-dimensional in situ morphometrics of Mycobacterium tuberculosis infection within lesions by optical mesoscopy and novel acid-fast staining

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Robert J. Francis ◽  
Gillian Robb ◽  
Lee McCann ◽  
Bhagwati Khatri ◽  
James Keeble ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Three Dimensional ◽  
Large Field ◽  
Staining Procedure ◽  
3D Analysis ◽  
Mycobacterium Tuberculosis Infection ◽  
In Vivo Models ◽  
Novel Approach

AbstractTuberculosis (TB) preclinical testing relies on in vivo models including the mouse aerosol challenge model. The only method of determining colony morphometrics of TB infection in a tissue in situ is two-dimensional (2D) histopathology. 2D measurements consider heterogeneity within a single observable section but not above and below, which could contain critical information. Here we describe a novel approach, using optical clearing and a novel staining procedure with confocal microscopy and mesoscopy, for three-dimensional (3D) measurement of TB infection within lesions at sub-cellular resolution over a large field of view. We show TB morphometrics can be determined within lesion pathology, and differences in infection with different strains of Mycobacterium tuberculosis. Mesoscopy combined with the novel CUBIC Acid-Fast (CAF) staining procedure enables a quantitative approach to measure TB infection and allows 3D analysis of infection, providing a framework which could be used in the analysis of TB infection in situ.

scholarly journals Artificial Tumor Microenvironments in Neuroblastoma

Cancers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1629
Author(s):  
Colin H. Quinn ◽  
Andee M. Beierle ◽  
Elizabeth A. Beierle
Keyword(s):  
Extracellular Matrix ◽  
Three Dimensional ◽  
Therapeutic Interventions ◽  
3D Bioprinting ◽  
Culture Studies ◽  
In Vivo Models ◽  
Novel Treatments ◽  
Tumor Microenvironments ◽  
Novel Approach

In the quest to advance neuroblastoma therapeutics, there is a need to have a deeper understanding of the tumor microenvironment (TME). From extracellular matrix proteins to tumor associated macrophages, the TME is a robust and diverse network functioning in symbiosis with the solid tumor. Herein, we review the major components of the TME including the extracellular matrix, cytokines, immune cells, and vasculature that support a more aggressive neuroblastoma phenotype and encumber current therapeutic interventions. Contemporary treatments for neuroblastoma are the result of traditional two-dimensional culture studies and in vivo models that have been translated to clinical trials. These pre-clinical studies are costly, time consuming, and neglect the study of cofounding factors such as the contributions of the TME. Three-dimensional (3D) bioprinting has become a novel approach to studying adult cancers and is just now incorporating portions of the TME and advancing to study pediatric solid. We review the methods of 3D bioprinting, how researchers have included TME pieces into the prints, and highlight present studies using neuroblastoma. Ultimately, incorporating the elements of the TME that affect neuroblastoma responses to therapy will improve the development of innovative and novel treatments. The use of 3D bioprinting to achieve this aim will prove useful in developing optimal therapies for children with neuroblastoma.

In vitro and in vivo polysaccharides assembly: ultrastructural and cytochemical study of growing plant cell wall components.

1978 ◽  
Vol 36 (2) ◽  
pp. 434-435
Author(s):  
D. Reis ◽  
B. Vian ◽  
J. C. Roland
Keyword(s):  
Cell Wall ◽  
Self Assembly ◽  
Plant Cell Wall ◽  
Higher Plants ◽  
Three Dimensional ◽  
Cytochemical Study ◽  
Wall Components

Wall morphogenesis in higher plants is a problem still open to controversy. Until now the possibility of a transmembrane control and the involvement of microtubules were mostly envisaged. Self-assembly processes have been observed in the case of walls of Chlamydomonas and bacteria. Spontaneous gelling interactions between xanthan and galactomannan from Ceratonia have been analyzed very recently. The present work provides indications that some processes of spontaneous aggregation could occur in higher plants during the formation and expansion of cell wall.Observations were performed on hypocotyl of mung bean (Phaseolus aureus) for which growth characteristics and wall composition have been previously defined.In situ, the walls of actively growing cells (primary walls) show an ordered three-dimensional organization (fig. 1). The wall is typically polylamellate with multifibrillar layers alternately transverse and longitudinal. Between these layers intermediate strata exist in which the orientation of microfibrils progressively rotates. Thus a progressive change in the morphogenetic activity occurs.

Three-Dimensional Subcellular Organization of Hepatocytes in Intact Liver: Simultaneous Visualization of Cytoskeletal and Membrane Markers by Confocal Microscopy

1996 ◽  
Vol 54 ◽  
pp. 288-289
Author(s):  
Greg V. Martin ◽  
Ann L. Hubbard
Keyword(s):  
Three Dimensional ◽  
Integral Membrane Proteins ◽  
Polarized Secretion ◽  
Microscope Images ◽  
Computer Aided ◽  
Intracellular Organelles ◽  
Cytoskeletal Elements ◽  
Simultaneous Visualization

The microtubule (MT) cytoskeleton is necessary for many of the polarized functions of hepatocytes. Among the functions dependent on the MT-based cytoskeleton are polarized secretion of proteins, delivery of endocytosed material to lysosomes, and transcytosis of integral plasma membrane (PM) proteins. Although microtubules have been shown to be crucial to the establishment and maintenance of functional and structural polarization in the hepatocyte, little is known about the architecture of the hepatocyte MT cytoskeleton in vivo, particularly with regard to its relationship to PM domains and membranous organelles. Using an in situ extraction technique that preserves both microtubules and cellular membranes, we have developed a protocol for immunofluorescent co-localization of cytoskeletal elements and integral membrane proteins within 20 µm cryosections of fixed rat liver. Computer-aided 3D reconstruction of multi-spectral confocal microscope images was used to visualize the spatial relationships among the MT cytoskeleton, PM domains and intracellular organelles.

scholarly journals Gran1: A Granulysin-Derived Peptide with Potent Activity against Intracellular Mycobacterium tuberculosis

2021 ◽  
Vol 22 (16) ◽  
pp. 8392
Author(s):  
Reiner Noschka ◽  
Fanny Wondany ◽  
Gönül Kizilsavas ◽  
Tanja Weil ◽  
Gilbert Weidinger ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Mycobacterium Tuberculosis ◽  
Developmental Toxicity ◽  
Super Resolution ◽  
In Vivo Models ◽  
Large Size ◽  
Acid Fragment ◽  
Powerful Approach ◽  
Target Effects

Granulysin is an antimicrobial peptide (AMP) expressed by human T-lymphocytes and natural killer cells. Despite a remarkably broad antimicrobial spectrum, its implementation into clinical practice has been hampered by its large size and off-target effects. To circumvent these limitations, we synthesized a 29 amino acid fragment within the putative cytolytic site of Granulysin (termed “Gran1”). We evaluated the antimicrobial activity of Gran1 against the major human pathogen Mycobacterium tuberculosis (Mtb) and a panel of clinically relevant non-tuberculous mycobacteria which are notoriously difficult to treat. Gran1 efficiently inhibited the mycobacterial proliferation in the low micro molar range. Super-resolution fluorescence microscopy and scanning electron microscopy indicated that Gran1 interacts with the surface of Mtb, causing lethal distortions of the cell wall. Importantly, Gran1 showed no off-target effects (cytokine release, chemotaxis, cell death) in primary human cells or zebrafish embryos (cytotoxicity, developmental toxicity, neurotoxicity, cardiotoxicity). Gran1 was selectively internalized by macrophages, the major host cell of Mtb, and restricted the proliferation of the pathogen. Our results demonstrate that the hypothesis-driven design of AMPs is a powerful approach for the identification of small bioactive compounds with specific antimicrobial activity. Gran1 is a promising component for the design of AMP-containing nanoparticles with selective activity and favorable pharmacokinetics to be pushed forward into experimental in vivo models of infectious diseases, most notably tuberculosis.

scholarly journals In Situ Vitrification of Lung Cancer Organoids on a Microwell Array

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 624
Author(s):  
Qiang Liu ◽  
Tian Zhao ◽  
Xianning Wang ◽  
Zhongyao Chen ◽  
Yawei Hu ◽  
...  
Keyword(s):  
Lung Cancer ◽  
Drug Sensitivity ◽  
Simple Procedure ◽  
Three Dimensional ◽  
Cancer Drug ◽  
Microwell Array ◽  
Sensitivity Tests ◽  
Anti Cancer

Three-dimensional cultured patient-derived cancer organoids (PDOs) represent a powerful tool for anti-cancer drug development due to their similarity to the in vivo tumor tissues. However, the culture and manipulation of PDOs is more difficult than 2D cultured cell lines due to the presence of the culture matrix and the 3D feature of the organoids. In our other study, we established a method for lung cancer organoid (LCO)-based drug sensitivity tests on the superhydrophobic microwell array chip (SMAR-chip). Here, we describe a novel in situ cryopreservation technology on the SMAR-chip to preserve the viability of the organoids for future drug sensitivity tests. We compared two cryopreservation approaches (slow freezing and vitrification) and demonstrated that vitrification performed better at preserving the viability of LCOs. Next, we developed a simple procedure for in situ cryopreservation and thawing of the LCOs on the SMAR-chip. We proved that the on-chip cryopreserved organoids can be recovered successfully and, more importantly, showing similar responses to anti-cancer drugs as the unfrozen controls. This in situ vitrification technology eliminated the harvesting and centrifugation steps in conventional cryopreservation, making the whole freeze–thaw process easier to perform and the preserved LCOs ready to be used for the subsequent drug sensitivity test.

scholarly journals Targeting redox heterogeneity to counteract drug tolerance in replicating Mycobacterium tuberculosis

2019 ◽  
Vol 11 (518) ◽  
pp. eaaw6635 ◽  
Author(s):  
Richa Mishra ◽  
Sakshi Kohli ◽  
Nitish Malhotra ◽  
Parijat Bandyopadhyay ◽  
Mansi Mehta ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
Drug Tolerance ◽  
Antibiotic Tolerance ◽  
Lung Pathology ◽  
In Vivo Models ◽  
Drug Efflux Pumps ◽  
Major Drug ◽  
Hiv 1 ◽  
Multiple Antibiotics

The capacity of Mycobacterium tuberculosis (Mtb) to tolerate multiple antibiotics represents a major problem in tuberculosis (TB) management. Heterogeneity in Mtb populations is one of the factors that drives antibiotic tolerance during infection. However, the mechanisms underpinning this variation in bacterial population remain poorly understood. Here, we show that phagosomal acidification alters the redox physiology of Mtb to generate a population of replicating bacteria that display drug tolerance during infection. RNA sequencing of this redox-altered population revealed the involvement of iron-sulfur (Fe-S) cluster biogenesis, hydrogen sulfide (H2S) gas, and drug efflux pumps in antibiotic tolerance. The fraction of the pH- and redox-dependent tolerant population increased when Mtb infected macrophages with actively replicating HIV-1, suggesting that redox heterogeneity could contribute to high rates of TB therapy failure during HIV-TB coinfection. Pharmacological inhibition of phagosomal acidification by the antimalarial drug chloroquine (CQ) eradicated drug-tolerant Mtb, ameliorated lung pathology, and reduced postchemotherapeutic relapse in in vivo models. The pharmacological profile of CQ (Cmax and AUClast) exhibited no major drug-drug interaction when coadministered with first line anti-TB drugs in mice. Our data establish a link between phagosomal pH, redox metabolism, and drug tolerance in replicating Mtb and suggest repositioning of CQ to shorten TB therapy and achieve a relapse-free cure.

Intra-oral Models: Comparison of in situ Substrates

1992 ◽  
Vol 71 (3_suppl) ◽  
pp. 920-923 ◽  
Author(s):  
B. øgaard ◽  
G. Rølla
Keyword(s):  
Clinical Effects ◽  
Hard Tissue ◽  
In Vivo Models ◽  
Caries Model ◽  
Models Comparison ◽  
Risk Patients ◽  
Oral Conditions ◽  
Bovine Enamel

Numerous intra-oral caries models have been designed for clinical and mechanistic purposes. Several factors—such as human vs. bovine enamel, sound vs. demineralized tissues, lesion type, dentin vs. enamel, the severity of the cariogenic challenge, and the microflora—may influence the reactivity of the hard tissue and hence lesion development and progression. Some models use unextracted teeth and are true in vivo models, whereas in situ models are based on hard-tissue substrates in the form of slabs or sections. Models producing a moderate cariogenic challenge usually show a fluoride dose response. However, caries is increasingly becoming a problem limited to some high-risk patients and to lesions located to areas where severe challenges exist (e.g., fissures and pits). There is thus need for models that could mimic such situations. One of the requirements for intra-oral models producing severe cariogenic challenge conditions should probably be that it should be able to demineralize fluorapatite. A challenge for future caries research is to develop agents that have a better clinical effect in fissures and pits than those presently available. Because, in the past, much emphasis has been placed on remineralization of artificial lesions, more research on the demineralization process should be performed in the future, since this may give improved clinical effects. Ideally, an intra-oral caries model should take into account as many of the natural oral conditions as possible and minimize the degree of artificiality.

scholarly journals In vivo γδ T Cell Priming to Mycobacterial Antigens by Primary Mycobacterium tuberculosis Infection and Exposure to Nonpeptidic Ligands

1999 ◽  
Vol 5 (7) ◽  
pp. 471-476 ◽  
Author(s):  
Fabrizio Poccia ◽  
Miroslav Malkovsky ◽  
Aaron Pollak ◽  
Vittorio Colizzi ◽  
Guido Sireci ◽  
...  
Keyword(s):  
Mycobacterium Tuberculosis ◽  
T Cell ◽  
Tuberculosis Infection ◽  
Γδ T Cell ◽  
Mycobacterium Tuberculosis Infection ◽  
T Cell Priming ◽  
Mycobacterial Antigens

scholarly journals Gut organoids: mini-tissues in culture to study intestinal physiology and disease

2019 ◽  
Vol 317 (3) ◽  
pp. C405-C419 ◽  
Author(s):  
Mohammad Almeqdadi ◽  
Miyeko D. Mana ◽  
Jatin Roper ◽  
Ömer H. Yilmaz
Keyword(s):  
Cell Lines ◽  
Three Dimensional ◽  
Gastrointestinal Diseases ◽  
In Vivo Models ◽  
Intestinal Physiology ◽  
Microbe Interactions ◽  
Immortalized Cell ◽  
In Vitro Cell Cultures

In vitro, cell cultures are essential tools in the study of intestinal function and disease. For the past few decades, monolayer cellular cultures, such as cancer cell lines or immortalized cell lines, have been widely applied in gastrointestinal research. Recently, the development of three-dimensional cultures known as organoids has permitted the growth of normal crypt-villus units that recapitulate many aspects of intestinal physiology. Organoid culturing has also been applied to study gastrointestinal diseases, intestinal-microbe interactions, and colorectal cancer. These models are amenable to CRISPR gene editing and drug treatments, including high-throughput small-molecule testing. Three-dimensional intestinal cultures have been transplanted into mice to develop versatile in vivo models of intestinal disease, particularly cancer. Limitations of currently available organoid models include cost and challenges in modeling nonepithelial intestinal cells, such as immune cells and the microbiota. Here, we describe the development of organoid models of intestinal biology and the applications of organoids for study of the pathophysiology of intestinal diseases and cancer.

Sign in / Sign up

Export Citation Format

Share Document