Plant cell culture systems have become an attractive and sustainable approach to produce high‐value and commercially significant metabolites under controlled conditions. Strategies involving elicitor supplementation into plant cell culture media are employed to mimic natural conditions for increasing the metabolite yield. Studies on nanoparticles (NPs) that have investigated elicitation of specialized metabolism have shown the potential of NPs to be a substitute for biotic elicitors such as phytohormones and microbial extracts. Customizable physicochemical characteristics allow the design (...) of monodispersed‐, stimulus‐responsive‐, and hormone‐carrying‐NPs of precise geometries to enhance their elicitation capabilities based on target metabolite/plant cell culture type. We contextualize advances in NP‐mediated elicitation, especially stimulation of specialized metabolic pathways, the underlying mechanisms, impacts on gene regulation, and NP‐associated cytotoxicity. The novelty of the concept lies in unleashing the potential of designer NPs to enhance yield, harness metabolites, and transform nanoelicitation from exploratory investigations to a commercially viable strategy. (shrink)

Work with plant cell cultures has developed rapidly in recent years, progress being manifested particularly by the development of commercial process technology for the synthesis of selected natural products. The economics of operating a plant‐cell culture process are, however, still questionable, and a great deal still needs to be done to strengthen the underlying science before the technology can be regarded as industrially commonplace. Nonetheless, the great versatility of plants as centres of chemical synthesis suggests that, with (...) appropriate developments in cell culture technology, this area may have a significant role to play in the fine chemicals industry of the future. (shrink)

Endothelial cells in culture have, in the past, been a valuable but capricious tool to test hypotheses on the role of components of the blood vessel wall in such functions as blood pressure homeostasis, hemostasis, permeability, transport of macromolecules and the processing of circulating biologically active substances. Now techniques are becoming available for raising long‐term, large‐scale cultures that can be maintained reproducibly and without loss of phenotypic characteristics. The outlook for establishing endothelial cell factories invites speculation on some (...) far‐reaching possibilities, such as endothelial cell banks that could be used for seeding autogenous cells on vascular prostheses, artificial kidney tubing, heart valves, or corneas, or for virus production, or for synthesis by endothelial cells of products at present beyond the reach of bacterial cells. (shrink)

A cell contains many copies of mitochondrial DNA. The distribution of a mitochondrial gene mutation in a cell culture is governed by the way in which the mtDNA molecules of a cell are replicated and partitioned between the two daughter cells during mitosis. Assuming that this partition process is random, we describe the evolution of the mitochondrial genetic state of a cell culture. The mutated mtDNA is ultimately segregated and the rate of the trend (...) to segregation is relatively slow. It is nevertheless greatly accelerated if the model takes into account the spatial mtDNA partition by the mitochondrial compartments. (shrink)

Despite claims from prominent scientists that SARS‐CoV‐2 indubitably emerged naturally, the etiology of this novel coronavirus remains a pressing and open question: Without knowing the true nature of a disease, it is impossible for clinicians to appropriately shape their care, for policy‐makers to correctly gauge the nature and extent of the threat, and for the public to appropriately modify their behavior. Unless the intermediate host necessary for completing a natural zoonotic jump is identified, the dual‐use gain‐of‐function research practice of viral (...) serial passage should be considered a viable route by which the novel coronavirus arose. The practice of serial passage mimics a natural zoonotic jump, and offers explanations for SARS‐CoV‐2's distinctive spike‐protein region and its unexpectedly high affinity for angiotensin converting enzyme (ACE2), as well as the notable polybasic furin cleavage site within it. Additional molecular clues raise further questions, all of which warrant full investigation into the novel coronavirus's origins and a re‐examination of the risks and rewards of dual‐use gain‐of‐function research. (shrink)

Within the biotech era, art that addresses life issues and brings biological life into the artistic context cannot avoid using biotechnology as the technology that facilitates interventions into living matter. Art not only intervenes in the living matter in laboratories but aims to show and cultivate tissues and various living cultures in the gallery space. Galleries have turned from spaces for showing artifacts into event spaces, performances and workshops. In this context, the idea of growing living entities within the artistic (...) milieu testifies to a performative turn, a shift from representational to performative modes of art. Due to the imperative to perform, art which addresses biotechnology requires the presence of living tissues and other living substances in gallery spaces or spaces meant to show art to the public. The author identifies three sorts of microperformativity carried out by biotechnological art in the sense of managing life at the micro level. The most original of these and specific to art that works with living organisms involves the real-time action of living microorganisms or bioengineered tissues within the artistic context in full public view. For this sort of performativity, the artist induces microorganisms or engineered tissues to perform by themselves for the audience. Tratnik examines the project CellF by Guy Ben Ary as an example of such microperformativity. (shrink)

The emergence of a new tissue economy raises issues for the governance of risk and concepts of the body and self. This article explores the development of autologous cell therapies as a form of tissue engineering and considers how and why autologous applications are seen as less risky and more socially and politically acceptable. In a careful analysis of contemporary debates around the need for new international policies to regulate these technologies, we critically assess the discursive strategies employed to (...) support ideas of the body as a natural entity. Central to these debates are assumptions that autologous applications do not threaten the moral or corporeal integrity of the individual and that they are ‘an ethics-free zone’. Analysis reveals that concepts such as intercorporeality need to be refined if they are to assist our understanding of these cell-based therapies. We consider the biopolitics of Autologous Chondrocyte Implantation (ACI) in order to show the linkages between the culturing of cells, regulation and the reproduction of the self. (shrink)

Continuous culture techniques were developed in the early twentieth century to replace cumbersome studies of cell growth in batch cultures. In contrast to batch cultures, they constituted an open concept, as cells are forced to proliferate by adding new medium while cell suspension is constantly removed. During the 1940s and 1950s new devices have been designed—called “automatic syringe mechanism,” “turbidostat,” “chemostat,” “bactogen,” and “microbial auxanometer”—which allowed increasingly accurate quantitative measurements of bacterial growth. With these devices cell (...) growth came under the external control of the experimenters and thus accessible for developing a mathematical theory of growth kinetics—developed mainly by Jacques Monod, Aron Novick and Leo Szilard in the early 1950s and still in use today. The paper explores the development of continuous culture devices and claims that these devices are simulators for standard cells following specific requirements, in particular involving mathematical constraints in the design and setting of the devices as well as experiments. These requirements have led to contemporary designs of continuous culture techniques realizing a specific event-based flow algorithm able to simulate directed evolution and produce artificial cells and microorganisms. This current development is seen as an alternative approach to today’s synthetic biology. (shrink)

"Dying in the City of Blues: Sickle Cell Anemia and the Politics of Race and Health" by Keith Wailoo is reviewed.

This essay argues that the racialized geopolitics of the rhesus monkey trade conditioned the trajectory of tissue culture in polio research. Rhesus monkeys from north India were important experimental organisms in the American “war against polio” between the 1930s and 1950s. During this period, the National Foundation for Infantile Paralysis expended considerable effort to secure the nonhuman primate for researchers’ changing experimental agendas. The NFIP drew on transnational networks to export hundreds of thousands of rhesus monkeys from colonial and (...) later postcolonial India amid the geopolitical upheavals of World War II, the 1947 Partition, and the Cold War. In this essay, I trace how NFIP officials’ anxieties about the geopolitics of the monkey trade configured research imperatives in the war against polio. I show how their anxieties more specifically shaped investment in tissue culture techniques as a possible means of obviating dependence on the market in monkeys. I do so by offering a genealogy of the contingent convergence between the use of rhesus monkeys and HeLa cell cultures in the 1954 Salk vaccine trial evaluation. Through this genealogy, I emphasize the geopolitical dimensions of the search for the “right” experimental organisms, tissues, and cells for the “job” of scientific research. The technical transformation of polio research, I argue, relied on the convergence of disparate, racialized biomedical economies. (shrink)

Adenosine transport in cultured human umbilical vein endothelial cells (HUVEC) was characterized and shown to be mediated by a single facilitated diffusion mechanism. Initial rates of adenosine influx at 22 degrees C were saturable [apparent Michaelis constant, 69 +/- 10 mu M; maximum velocity (V-max), 600 +/- 70 pmol.10(6) cells(-1).s(-1)] and inhibited by nitrobenzylthioinosine (NBMPR). Formycin B had an unusually high affinity [inhibitory constant K-i), 18 +/- 4.3 mu M], whereas inosine had a low affinity (K-i, 440 +/- 68 mu (...) M) and nucleobases were without effect on adenosine influx. The number of transporters (1.2 x 10(6) sites/cell) was estimated by NBMPR equilibrium binding (apparent dissociation constant, 0.11 +/- 0.01 nM; maximum binding, 2.0 +/- 0.15 pmol/10(6) cells). In addition, we compared these endothelial cells with those obtained from cords from pregnancies complicated by diabetes (HUVEC-D), since embriopathy may occur in these conditions. HUVEC-D exhibited a 2.3-fold reduction in both the V-max for adenosine influx and the maximum number of NBMPR binding sites (260 +/- 40 pmol.10(6) cells(-1).s(-1) and 0.86 +/- 0.08 pmol/10(6) cells, respectively). However, the turnover number for each nucleoside transporter in normal and diabetic HUVEC was similar (approximate to 300 adenosine molecules/s). Adenosine metabolism at 10 mu M in HUVEC-D was modified compared with normal cells. Intracellular phosphorylation (> 90%) was the predominant pathway in normal HUVEC, whereas in HUVEC-D, substantial levels of adenine and adenosine were detected. The present results demonstrate therefore the downregulation of the NBMPR-sensitive nucleoside transporter and changes in adenosine metabolism in HUVEC from diabetic pregnancies. (shrink)

Our human embryonic stem cell debates are not simply about good or bad ethical arguments. The fetus and the embryo have instead become symbols for a larger set of value conflicts occasioned by social and cultural changes. Beneath our stem cell debates lie conflicts between those who would privilege scientific progress and individual choice and others who favour the sanctity of family life and traditional family roles. Also at work, on both the national and international levels, is the (...) use of the embryo by newly emergent social groups to express resentment against cultural elites. The organisational needs of religious groups have also played a role, with the issue of protection of the embryo and fetus serving as a useful means of rallying organisational allegiance in the Roman Catholic and evangelical communities. Because the epiphenomenal moral positions on the status and use of the embryo are driven by the powerful social, cultural or economic forces beneath them, they will most likely change only with shifts in the underlying forces that sustain them. (shrink)

The debate surrounding human embryonic stem cell research plays a crucial role in the culture wars. Those who embrace post-traditional morality not only see no ethical problem with the destruction of human embryos for research and therapies, but press for their use despite the greater potential for risk from the totipotent cells that are harvested from the destruction of human embryos as opposed to other kinds of stem cells. Indeed, there have been foreseeable negative consequences from such attempts (...) at treatment. Nonetheless, from the standpoint of traditional Christianity, the destruction of human embryos is expressly forbidden regardless of any potential positive outcomes. There is a fundamental cleft within the culture on such issues. (shrink)

BackgroundRich in different kind of potent cells, embryos are used in modern regenerative medicine and research. Neurobiologists today are pushing the boundaries for what can be done with embryos existing in the transitory margins of medicine. Therefore, there is a growing need to develop conceptual frameworks for interpreting the transformative cultural, biological and technical processes involving these aborted, donated and marginal embryos. This article is a contribution to this development of frameworks.MethodsThis article examines different emotional, cognitive and discursive strategies used (...) by neurobiologists in a foetal cell transplantation trial in Parkinson’s disease research, using cells harvested from aborted embryos. Two interviews were analysed in the light of former observations in the processing laboratories, using the anthropologist Mary Douglas’s concept of pollution behaviour and the linguist, philosopher, psychoanalyst and feminist Julia Kristeva’s concept of the abjective to explain and make sense of the findings.ResultsThe findings indicate that the labour performed by the researchers in the trial work involves transforming the foetal material practically, as well as culturally, from trash to treasure. The transformation process contains different phases, and in the interview material we observed that the foetal material or cells were considered objects, subjects or rejected as abject by the researchers handling them, depending on what phase of process or practice they referred to or had experience of. As demonstrated in the analysis, it is the human origin of the cell that makes it abjective and activates pollution discourse, when the researchers talk of their practice.ConclusionsThe marginal and ambiguous status of the embryo that emerges in the accounts turns the scientists handling foetal cells into liminal characters in modern medicine. Focusing on how practical as well as emotional and cultural strategies and rationalizations of the researchers emerge in interview accounts, this study adds insights on the rationale of practically procuring, transforming and utilizing the foetal material to the already existing studies focused on the donations. We also discuss why the use and refinement of a tissue, around which there is practical consensus but cultural ambiguity, deserves further investigation. (shrink)

“Stem Cells Dependently Arising and Empty” May 2021, Buddhism and Culture (a Korean-language Buddhist magazine sponsored by the Foundation for the Promotion of Korean Buddhism), Korea.

The global development of human embryonic stem cell science and its therapeutic applications are dependent on the nature of its engagement at national and international levels with key cultural values and beliefs concerning the moral status of the early human embryo. This article argues that the political need to reconcile the promise of new health technologies with the cultural costs of scientific advance, dependent in this case on the use of the human embryo, has been met by the evolution (...) of bioethics as a political community, transnational network, and bureaucratic device. Bioethics has become the political means for the creation of a global moral economy where the trading and exchange of values is normalized and legitimated. As a result of such trading, value compromises are produced capable of legitimizing the regulatory policies necessary for maintaining public trust in the new science. (shrink)

The PIWI-interacting RNA pathway, one of the major eukaryotic small RNA silencing pathways, is a genome surveillance system that silences selfish genes in animal gonads. piRNAs guide PIWI protein to target genes through Watson–Crick RNA–RNA base-parings. Loss of piRNA function causes genome instability, inducing failure in gametogenesis and infertility. Studies using fruit flies and mice as key experimental models have resulted in tremendous progress in understanding the mechanism underlying the piRNA pathway. Recent work using cultured silkworm germline cells has also (...) expanded our knowledge of piRNA biogenesis in particular, since these silkworm cells are the only cells of germline origin that can be cultured. In this review, we describe elucidation of the piRNA pathway using cultured silkworm cells as an experimental model by focusing on recent work in biochemistry and structural biology. Earlier studies that made important contributions to the field are also described. PIWI-interacting RNAs are germline-enriched small RNAs that silence transposons to maintain genome integrity. Recently, cultured silkworm germline cells such as BmN4 made great contributions to understand the mechanism underlying piRNA biogenesis in particular. In this review, we highlight the recent progress in biochemical and structural biology. (shrink)

During somitogenesis an oscillatory mechanism termed the “segmentation” clock generates periodic waves of gene expression, which translate into the periodic spatial pattern manifest as somites. The dynamic expression of the clock genes shares the same periodicity as somitogenesis. Notch signaling is believed to play a role in the segmentation clock mechanism. The paper by Hirata et al.(1) identifies a biological clock in cultured cells that is dependent upon the Notch target gene Hes1, and which shows a periodicity similar to that (...) of the segmentation clock. This finding opens the possibility that the same oscillator mechanism might also operate in other tissues or cell types. BioEssays 25:200–203, 2003. © 2003 Wiley Periodicals, Inc. (shrink)

During somitogenesis an oscillatory mechanism termed the “segmentation” clock generates periodic waves of gene expression, which translate into the periodic spatial pattern manifest as somites. The dynamic expression of the clock genes shares the same periodicity as somitogenesis. Notch signaling is believed to play a role in the segmentation clock mechanism. The paper by Hirata et al.(1) identifies a biological clock in cultured cells that is dependent upon the Notch target gene Hes1, and which shows a periodicity similar to that (...) of the segmentation clock. This finding opens the possibility that the same oscillator mechanism might also operate in other tissues or cell types. BioEssays 25:200–203, 2003. © 2003 Wiley Periodicals, Inc. (shrink)

This study shows that double thymidine block treatment efficiently arrests the EO771 cells in the S‐phase without altering cell growth or survival. A long‐term analysis of cell behavior, using 5(6)‐carboxyfluorescein diacetate N‐succinimidyl ester (CFSE) staining, show synchronization to be stable and consistent over time. The EO771 cell line is a medullary breast‐adenocarcinoma cell line isolated from a spontaneous murine mammary tumor, and can be used to generate murine tumor implantation models. Different biological (serum or amino acid (...) deprivation), physical (elutriation, mitotic shake‐off), or chemical (colchicine, nocodazole, thymidine) treatments are widely used for cell synchronization. Of the different methods tested, the double thymidine block is the most efficient for synchronization of murine EO771 cells if a large quantity of highly synchronized cells is recommended to study functional and biochemical events occurring in specific points of cell cycle progression. (shrink)

An analysis is presented of published methods that have been used by experimenters to justify the reliability of the theory of invasion of microorganisms into cultured cells. The results show that, to demonstrate this invasion, many experimenters used two or more methods that were based on independent technical and theoretical principles, and by doing so improved the reliability of the theory. Subsequently I compare this strategy of 'multiple derivability' with other strategies, discussed in the literature in relation to the mesosome, (...) a bacterial organelle that had been detected with the electron microsope, but which appeared later to be an artifact. I propose that different strategies have been applied in this problem, and multiple derivability may have been the decisive one. Finally I discuss the idea that multiple derivability may help to anchor theories in a larger network of theories. (shrink)

Long ago, I set out to solve a problem, but something happened along the way: I was diverted by an unexpected observation. Thereafter, the direction of my research was guided at each stage by increasing familiarity with the experimental material and what could be done with it. The result was the birth of therapy with cultured keratinocytes. Subsequent developments soon led to the formation of the company Biosurface Technology (later taken over by the Genzyme Corporation), which provided autologous cultures for (...) burn victims in many parts of the world. Further progress by others led to new therapeutic applications of cultured keratinocytes, such as treatment of an ocular disease and gene therapy. Unfortunately, there have developed serious regulatory problems that are a danger to future progress. As described in this brief history, the initial stages of development of cell therapy for the treatment of human disease were possible only because there was no restraint by committees or governmental regulations. BioEssays 30:897–903, 2008. © 2008 Wiley Periodicals, Inc. (shrink)

Brussen, Kerri Anne Sex Cells, written by Rene Almeling, describes the commercial market that has emerged in the United States for human eggs and sperm. Almeling examines how agendas that are economically, biologically and culturally driven have lead to distinctly different practices within egg agencies and sperm banks. Further, she observes how these practices subsequently shape an individual's perception of the commodification of human gametes.

Stem cell research has entered the public consciousness through the media. Proponents and opponents of all such research, or of human embryonic stem cell research specifically, engage in heated exchanges in the modern public forum where stakeholders negotiate, the agora. One common claim that emerges from the fray is that a particular type of stem cell research should be pursued as the most promising path toward the reduction of suffering and untimely death for all of humanity. Upon (...) evaluation, experimental data regarding the potential role of stem cells in regenerative therapies for three conditions—spinal cord injury, type 1 diabetes, and cardiovascular disease—tell distinct, complex, and inconclusive stories. Further analyses in this article incorporate realistic considerations of a broad range of relevant factors--limited funding for biomedical research, media motives, the discordance hypothesis of evolutionary medicine, the relationship between religion and science, medical care in developing nations, and culture wars over abortion. Holistic investigation inspired by the current agora conversation supports the need to drastically change interactions regarding stem cell research so that its potential to benefit humanity may be more fully realized. (shrink)

Single‐cell microinjection has been successfully used to deliver exogenous proteins, cDNA constructs, peptides, drugs and particles into transfection‐challenged cells. With precisely controlled delivery dosage and timing, microinjection has been used in many studies of primary cultured cells, transgenic animal production, in vitro fertilization and RNA inference. This review discusses the advantages and limits of microinjection as a mechanical delivery method and its applications to attached and suspended cells. BioEssays 30:606–610, 2008. © 2008 Wiley Periodicals, Inc.

Stem cells and the emerging field of regenerative medicine are at the frontiers of modern medicine. These areas of scientific inquiry suggest that in the future, damaged tissue and organs might be repaired through personalized cell therapy as easily as the body repairs itself, revolutionizing the treatment of numerous diseases. Yet the use of stem cells is fraught with ethical and public policy dilemmas that challenge scientists, clinicians, the public health community, and people of good will everywhere. How shall (...) we deal with these amazing biomedical advances, and how can we talk about potential breakthroughs with both moral and scientific intelligence? This book provides an innovative look at these vexing issues through a series of innovative Socratic dialogues that elucidate key scientific and ethical points in an approachable manner. Addressing the cultural and value issues underlying stem cell research while also educating readers about stem cells' biological function and medical applications, _Stem Cell Dialogues_ features fictional characters engaging in compelling inquiry and debate. Participants investigate the scientific, political, and socioethical dimensions of stem cell science using actual language, analysis, and arguments taken from scientific, philosophical, and popular literature. Each dialogue centers on a specific, recognizable topic, such as the policies implemented by the George W. Bush administration restricting the use of embryonic stem cells; the potential role of stem cells in personalized medicine; the ethics of cloning; and the sale of eggs and embryos. Additionally, speakers debate the use of stem cells to treat paralysis, diabetes, stroke effects, macular degeneration, and cancer. Educational, entertaining, and rigorously researched, _Stem Cell Dialogues_ should be included in any effort to help the public understand the science, ethics, and policy concerns of this promising field. (shrink)

: Catholic teaching has no moral difficulties with research on stem cells derived from adult stem cells or fetal cord blood. The ethical problem comes with embryonic stem cells since their genesis involves the destruction of a human embryo. However, there seems to be significant promise of health benefits from such research. Although Catholic teaching does not permit any destruction of human embryos, the question remains whether researchers in a Catholic institution, or any researchers opposed to destruction of human embryos, (...) could participate in research on cultured embryonic stem cells, or whether a Catholic institution could use any therapy that ultimately results from such research. This position paper examines how such research could be conducted legitimately in a Catholic institution by using an ethical analysis involving a narrative context, the nature of the moral act, and the principle of material cooperation, along with references to significant ethical assessments. It also offers tentative guidelines that could be used by a Catholic institution in implementing such research. (shrink)

Since the early nineteenth century a membrane or wall has been central to the cell’s identity as the elementary unit of life. Yet the literally and metaphorically marginal status of the cell membrane made it the site of clashes over the definition of life and the proper way to study it. In this article I show how the modern cell membrane was conceived of by analogy to the first “artificial cell,” invented in 1864 by the chemist (...) Moritz Traube (1826–1894), and reimagined by the plant physiologist Wilhelm Pfeffer (1845–1920) as a precision osmometer. Pfeffer’s artificial cell osmometer became the conceptual and empirical basis for the law of dilute solutions in physical chemistry, but his use of an artificial analogue to theorize the existence of the plasma membrane as distinct from the cell wall prompted debate over whether biology ought to be more closely unified with the physical sciences, or whether it must remain independent as the science of life. By examining how the histories of plant physiology and physical chemistry intertwined through the artificial cell, I argue that modern biology relocated vitality from protoplasmic living matter to nonliving chemical substances—or, in broader cultural terms, that the disenchantment of life was accompanied by the (re)enchantment of ordinary matter. (shrink)

Retroviral lineage tracing experiments suggest that the cortical ventricular zone is composed of a mixture of precursor cell types. The majority generate a single cell type (neurones, astrocytes or oligodendrocytes) and the remainder generate neurones and a single type of glial cell. Pluripotential precursor cells, that have the ability to generate all three cell types, are not observed. A recent paper, however, reports that when single ventricular zone cells are cultured in isolation, a small percentage of (...) these cells are pluripotential(1). This review will discuss what this knowledge tells us about cortical development. (shrink)