Plasmodium falciparum biology: analysis of in vitro versus in vivo growth conditions

Acyl-lipids are vital components for all life functions of plants. They are widely studied using often in vitro conditions to determine inter alia the impact of genetic modifications and the description of biochemical and physiological functions of enzymes responsible for acyl-lipid metabolism. What is currently lacking is knowledge of if these results also hold in real environments—in in vivo conditions. Our study focused on the comparative analysis of both in vitro and in vivo growth conditions and their impact on the acyl-lipid metabolism of Camelina sativa leaves. The results indicate that in vitro conditions significantly decreased the lipid contents and influenced their composition. In in vitro conditions, galactolipid and trienoic acid (16:3 and 18:3) contents significantly declined, indicating the impairment of the prokaryotic pathway. Discrepancies also exist in the case of acyl-CoA:lysophospholipid acyltransferases (LPLATs). Their activity increased about 2–7 times in in vitro conditions compared to in vivo. In vitro conditions also substantially changed LPLATs’ preferences towards acyl-CoA. Additionally, the acyl editing process was three times more efficient in in vitro leaves. The provided evidence suggests that the results of acyl-lipid research from in vitro conditions may not completely reflect and be directly applicable in real growth environments.

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Structural studies of the capsular polysaccharide and lipopolysaccharide O-antigen of Aeromonas salmonicida strain 80204-1 produced under in vitro and in vivo growth conditions

European Journal of Biochemistry ◽

10.1111/j.1432-1033.2004.04410.x ◽

2004 ◽

Vol 271 (22) ◽

pp. 4507-4516 ◽

Cited By ~ 20

Author(s):

Zhan Wang ◽

Suzon Larocque ◽

Evgeny Vinogradov ◽

Jean-Robert Brisson ◽

Andrew Dacanay ◽

...

Keyword(s):

Capsular Polysaccharide ◽

Growth Conditions ◽

Aeromonas Salmonicida ◽

Structural Studies ◽

O Antigen ◽

In Vivo Growth

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Gene Expression of Commensal Lactobacillus johnsonii Strain NCC533 during In Vitro Growth and in the Murine Gut

Journal of Bacteriology ◽

10.1128/jb.00991-07 ◽

2007 ◽

Vol 189 (22) ◽

pp. 8109-8119 ◽

Cited By ~ 45

Author(s):

Emmanuel Denou ◽

Bernard Berger ◽

Caroline Barretto ◽

Jean-Michel Panoff ◽

Fabrizio Arigoni ◽

...

Keyword(s):

Stationary Phase ◽

Viable Cell ◽

Growth Conditions ◽

In Vitro Growth ◽

Lactobacillus Johnsonii ◽

Cell Counts ◽

Expression Of Genes ◽

In Vivo Growth

ABSTRACT Work with pathogens like Vibrio cholerae has shown major differences between genes expressed in bacteria grown in vitro and in vivo. To explore this subject for commensals, we investigated the transcription of the Lactobacillus johnsonii NCC533 genome during in vitro and in vivo growth using the microarray technology. During broth growth, 537, 626, and 277 of the 1,756 tested genes were expressed during exponential phase, “adaptation” (early stationary phase), and stationary phase, respectively. One hundred one, 150, and 33 genes, respectively, were specifically transcribed in these three phases. To explore the in vivo transcription program, we fed L. johnsonii containing a resistance plasmid to antibiotic-treated mice. After a 2-day washout phase, we determined the viable-cell counts of lactobacilli that were in the lumina and associated with the mucosae of different gut segments. While the cell counts showed a rather uniform distribution along the gut, we observed marked differences with respect to the expression of the Lactobacillus genome. The largest number of transcribed genes was in the stomach (n = 786); the next-largest numbers occurred in the cecum (n = 391) and the jejunum (n = 296), while only 26 Lactobacillus genes were transcribed in the colon. In vitro and in vivo transcription programs overlapped only partially. One hundred ninety-one of the transcripts from the lactobacilli in the stomach were not detected during in vitro growth; 202 and 213 genes, respectively, were transcribed under all in vitro and in vivo conditions; but the core transcriptome for all growth conditions comprised only 103 genes. Forty-four percent of the NCC533 genes were not detectably transcribed under any of the investigated conditions. Nontranscribed genes were clustered on the genome and enriched in the variable-genome part. Our data revealed not only major differences between in vitro- and in vivo-expressed genes in a Lactobacillus gut commensal organism but also marked changes in the expression of genes along the digestive tract.

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Altered expression of a metformin-mediated radiation response in SA-NH and FSa tumor cells treated under in vitro and in vivo growth conditions

International Journal of Radiation Biology ◽

10.1080/09553002.2017.1304592 ◽

2017 ◽

Vol 93 (7) ◽

pp. 665-675 ◽

Cited By ~ 1

Author(s):

Jeffrey S. Murley ◽

Richard C. Miller ◽

Raziye Rana Senlik ◽

Alfred W. Rademaker ◽

David J. Grdina

Keyword(s):

Tumor Cells ◽

Growth Conditions ◽

Radiation Response ◽

Altered Expression ◽

In Vivo Growth

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Ultrastructural observations on the in vitro cytoadherence of Plasmodium falciparum infected red blood cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100162132 ◽

1990 ◽

Vol 48 (3) ◽

pp. 914-915

Author(s):

D.J.P. Ferguson ◽

A.R. Berendt ◽

J. Tansey ◽

K. Marsh ◽

C.I. Newbold

Keyword(s):

Plasmodium Falciparum ◽

Red Blood Cells ◽

Blood Cells ◽

Umbilical Vein ◽

Cell Types ◽

Amelanotic Melanoma ◽

Cytoplasmic Process ◽

Umbilical Vein Endothelial Cells

In human malaria, the most serious clinical manifestation is cerebral malaria (CM) due to infection with Plasmodium falciparum. The pathology of CM is thought to relate to the fact that red blood cells containing mature forms of the parasite (PRBC) cytoadhere or sequester to post capillary venules of various tissues including the brain. This in vivo phenomenon has been studied in vitro by examining the cytoadherence of PRBCs to various cell types and purified proteins. To date, three Ijiost receptor molecules have been identified; CD36, ICAM-1 and thrombospondin. The specific changes in the PRBC membrane which mediate cytoadherence are less well understood, but they include the sub-membranous deposition of electron-dense material resulting in surface deformations called knobs. Knobs were thought to be essential for cytoadherence, lput recent work has shown that certain knob-negative (K-) lines can cytoadhere. In the present study, we have used electron microscopy to re-examine the interactions between K+ PRBCs and both C32 amelanotic melanoma cells and human umbilical vein endothelial cells (HUVEC).We confirm previous data demonstrating that C32 cells possess numerous microvilli which adhere to the PRBC, mainly via the knobs (Fig. 1). In contrast, the HUVEC were relatively smooth and the PRBCs appeared partially flattened onto the cell surface (Fig. 2). Furthermore, many of the PRBCs exhibited an invagination of the limiting membrane in the attachment zone, often containing a cytoplasmic process from the endothelial cell (Fig. 2).

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Stage-dependent effect of deferoxamine on growth of Plasmodium falciparum in vitro

Blood ◽

10.1182/blood.v76.6.1250.1250 ◽

1990 ◽

Vol 76 (6) ◽

pp. 1250-1255 ◽

Cited By ~ 36

Author(s):

S Whitehead ◽

TE Peto

Keyword(s):

Plasmodium Falciparum ◽

Growth Inhibition ◽

Antimalarial Activity ◽

Clinical Malaria ◽

Inhibitory Effect ◽

Parasite Development ◽

And Control ◽

Speed Of Onset

Abstract Deferoxamine (DF) has antimalarial activity that can be demonstrated in vitro and in vivo. This study is designed to examine the speed of onset and stage dependency of growth inhibition by DF and to determine whether its antimalarial activity is cytostatic or cytocidal. Growth inhibition was assessed by suppression of hypoxanthine incorporation and differences in morphologic appearance between treated and control parasites. Using synchronized in vitro cultures of Plasmodium falciparum, growth inhibition by DF was detected within a single parasite cycle. Ring and nonpigmented trophozoite stages were sensitive to the inhibitory effect of DF but cytostatic antimalarial activity was suggested by evidence of parasite recovery in later cycles. However, profound growth inhibition, with no evidence of subsequent recovery, occurred when pigmented trophozoites and early schizonts were exposed to DF. At this stage in parasite development, the activity of DF was cytocidal and furthermore, the critical period of exposure may be as short as 6 hours. These observations suggest that iron chelators may have a role in the treatment of clinical malaria.

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Regeneration linked miRNA modify tumor phenotype and can enforce multi-lineage growth arrest in vivo

Scientific Reports ◽

10.1038/s41598-021-90009-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Siamak Salehi ◽

Oliver D. Tavabie ◽

Augusto Villanueva ◽

Julie Watson ◽

David Darling ◽

...

Keyword(s):

Cell Proliferation ◽

Growth Inhibition ◽

Tumor Aggressiveness ◽

Novel Treatment ◽

Tumor Phenotype ◽

Aggressive Tumor ◽

In Vivo Growth ◽

Regulation Of Regeneration

AbstractRegulated cell proliferation is an effector mechanism of regeneration, whilst dysregulated cell proliferation is a feature of cancer. We have previously identified microRNA (miRNA) that regulate successful and failed human liver regeneration. We hypothesized that these regulators may directly modify tumor behavior. Here we show that inhibition of miRNAs -503 and -23a, alone or in combination, enhances tumor proliferation in hepatocyte and non-hepatocyte derived cancers in vitro, driving more aggressive tumor behavior in vivo. Inhibition of miRNA-152 caused induction of DNMT1, site-specific methylation with associated changes in gene expression and in vitro and in vivo growth inhibition. Enforced changes in expression of two miRNA recapitulating changes observed in failed regeneration led to complete growth inhibition of multi-lineage cancers in vivo. Our results indicate that regulation of regeneration and tumor aggressiveness are concordant and that miRNA-based inhibitors of regeneration may constitute a novel treatment strategy for human cancers.

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In vitro and in vivo inhibition of malaria parasite infection by monoclonal antibodies against Plasmodium falciparum circumsporozoite protein (CSP)

Scientific Reports ◽

10.1038/s41598-021-84622-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Merricka C. Livingstone ◽

Alexis A. Bitzer ◽

Alish Giri ◽

Kun Luo ◽

Rajeshwer S. Sankhala ◽

...

Keyword(s):

Plasmodium Falciparum ◽

Monoclonal Antibodies ◽

Disease Burden ◽

Vaccine Candidate ◽

Specific Binding ◽

Circumsporozoite Protein ◽

Target Epitope ◽

Selection Of

AbstractPlasmodium falciparum malaria contributes to a significant global disease burden. Circumsporozoite protein (CSP), the most abundant sporozoite stage antigen, is a prime vaccine candidate. Inhibitory monoclonal antibodies (mAbs) against CSP map to either a short junctional sequence or the central (NPNA)n repeat region. We compared in vitro and in vivo activities of six CSP-specific mAbs derived from human recipients of a recombinant CSP vaccine RTS,S/AS01 (mAbs 317 and 311); an irradiated whole sporozoite vaccine PfSPZ (mAbs CIS43 and MGG4); or individuals exposed to malaria (mAbs 580 and 663). RTS,S mAb 317 that specifically binds the (NPNA)n epitope, had the highest affinity and it elicited the best sterile protection in mice. The most potent inhibitor of sporozoite invasion in vitro was mAb CIS43 which shows dual-specific binding to the junctional sequence and (NPNA)n. In vivo mouse protection was associated with the mAb reactivity to the NANPx6 peptide, the in vitro inhibition of sporozoite invasion activity, and kinetic parameters measured using intact mAbs or their Fab fragments. Buried surface area between mAb and its target epitope was also associated with in vivo protection. Association and disconnects between in vitro and in vivo readouts has important implications for the design and down-selection of the next generation of CSP based interventions.

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