bims-mricoa Biomed News
on MRI contrast agents
Issue of 2021–10–10
three papers selected by
Merve Yavuz, Bilkent University



  1. Sheng Wu Gong Cheng Xue Bao. 2021 Sep 25. 37(9): 3190-3200
      The targeting of anti-tumor drugs is an important means of tumor treatment and reducing drug side effects. Oxygen-depleted hypoxic regions in the tumour, which oxygen consumption by rapidly proliferative tumour cells, are generally resistant to therapies. Magnetotactic bacteria (MTB) are disparate array of microorganism united by the ability to biomineralize membrane-encased, single-magnetic-domain magnetic crystals (magnetosomes) of minerals magnetite or greigite. MTB by means of flagella, migrate along geomagnetic field lines and towards low oxygen concentrations. MTB have advantage of non-cytotoxicity and excellent biocompatibility, moreover magnetosomes (BMs) is more powerful than artificial magnetic nanoparticles(MNPs). This review has generally described the biological and physical properties of MTB and magnetosomes, More work deals with MTB which can be used to transport drug into tumor based on aerotactic sensing system as well as the competition of iron which is a key factor to proliferation of tumor. In addition, we summarized the research of magnetosomes, which be used as natural nanocarriers for chemotherapeutics, antibodies, vaccine DNA. Finally, We analyzed the problems faced in the tumor treatment using of MTB and bacterial magnetosomes and prospect development trends of this kind of therapy.
    Keywords:  drug delivery systems; magnetosomes; magnetotactic bacteria; tumour hypoxic regions
    DOI:  https://doi.org/10.13345/j.cjb.210263
  2. Nat Rev Drug Discov. 2021 Oct 06.
      The steadfast advance of the synthetic biology field has enabled scientists to use genetically engineered cells, instead of small molecules or biologics, as the basis for the development of novel therapeutics. Cells endowed with synthetic gene circuits can control the localization, timing and dosage of therapeutic activities in response to specific disease biomarkers and thus represent a powerful new weapon in the fight against disease. Here, we conceptualize how synthetic biology approaches can be applied to programme living cells with therapeutic functions and discuss the advantages that they offer over conventional therapies in terms of flexibility, specificity and predictability, as well as challenges for their development. We present notable advances in the creation of engineered cells that harbour synthetic gene circuits capable of biological sensing and computation of signals derived from intracellular or extracellular biomarkers. We categorize and describe these developments based on the cell scaffold (human or microbial) and the site at which the engineered cell exerts its therapeutic function within its human host. The design of cell-based therapeutics with synthetic biology is a rapidly growing strategy in medicine that holds great promise for the development of effective treatments for a wide variety of human diseases.
    DOI:  https://doi.org/10.1038/s41573-021-00285-3
  3. ACS Biomater Sci Eng. 2021 Oct 05.
      Magnetic tissue engineering is one of the rapidly emerging and promising directions of tissue engineering and biofabrication where the magnetic field is employed as temporal removal support or scaffold. Iron oxide nanoparticles are used to label living cells and provide the desired magnetic properties. Recently, polymer microcapsules loaded with iron oxide nanoparticles have been proposed as a novel approach to designing magnetic materials with high local concentrations. These microcapsules can be readily internalized and retained intracellularly for a long time in various types of cells. The low cytotoxicity of these microcapsules was previously shown in 2D cell culture. This paper has demonstrated that cells containing these nontoxic nanomaterials can form viable 3D tissue spheroids for the first time. The spheroids retained labeled fluorescent microcapsules with magnetic nanoparticles without a detectable cytotoxic effect. The high concentration of packed nanoparticles inside the microcapsules enables the evident magnetic properties of the labeled spheroids to be maintained. Finally, magnetic spheroids can be effectively used for magnetic patterning and biofabrication of tissue-engineering constructs.
    Keywords:  iron oxide nanoparticles; magnetic patterning; magnetic tissue engineering; magnetite containing polymer microcapsules; tissue spheroids
    DOI:  https://doi.org/10.1021/acsbiomaterials.1c00805