Effect of Size, Shape, and Composition on the Interaction of Different Nanomaterials with HeLa Cells

The application of nanomaterials in the fields of medicine and biotechnology is of enormous interest, particularly in the areas where traditional solutions have failed. Unfortunately, there is very little information on how to optimize the preparation of nanomaterials for their use in cell culture and on the effects that these can trigger on standard cellular systems. These data are pivotal in nanobiotechnology for the development of different applications and to evaluate/compare the cytotoxicity among the different nanomaterials or studies. The lack of information drives many laboratories to waste resources performing redundant comparative tests that often lead to partial answers due to differences in (i) the nature of the start-up material, (ii) the preparation, (iii) functionalization, (iv) resuspension, (v) the stability/dose of the nanomaterial, etc. These variations in addition to the different analytical systems contribute to the artefactual interpretation of the effects of nanomaterials and to inconsistent conclusions between different laboratories. Here, we present a brief review of a wide range of nanomaterials (nanotubes, various nanoparticles, graphene oxide, and liposomes) with HeLa cells as a reference cellular system. These human cells, widely used as cellular models for many studies, represent a reference system for comparative studies between different nanomaterials or conditions and, in the last term, between different laboratories.This work has been supported by the Spanish MINECO and European FEDER under Project ref. PI16/000496, the NanoBioApp Network Ref. MINECO-17-MAT2016-81955-REDT. We thank IDIVAL for INNVAL15/16, INNVAL 17/11, PREVAL 16/03, 16/02, 17/04, and the Raman4clinics BMBS COST Actions BM1401 and TD1402. We also thank Débora Muñoz for her technical assistance. We are grateful to the Nikon A1R Laser Microscopy Unit and the TEM Unit of the IDIVAL Institute

Biodegradable multi-walled carbon nanotubes trigger anti-tumoral effects

Carbon nanotubes are of huge biotechnological interest because they can penetrate most biological barriers and, inside cells, can biomimetically interact with the cytoskeletal filaments, triggering anti-proliferative and cytotoxic effects in highly dividing cells. Unfortunately, their intrinsic properties and bio-persistence represent a putative hazard that relapses their application as therapies against cancer. Here we investigate mild oxidation treatments to improve the intracellular enzymatic digestion of MWCNTs, but preserving their morphology, responsible for their intrinsic cytotoxic properties. Cell imaging techniques and confocal Raman spectroscopic signature analysis revealed that cultured macrophages can degrade bundles of oxidized MWCNTs (o-MWCNTs) in a few days. The isolation of nanotubes from these phagocytes 96 hours after exposure confirmed a significant reduction of approximately 30% in the total length of these filaments compared to the control o-MWCNTs extracted from the cell culture medium, or the intracellular pristine MWCNTs. More interestingly, in vivo single intratumoral injections of o-MWCNTs triggered ca. 30% solid melanoma tumour growth-inhibitory effects while displaying significant signs of biodegradation at the tumoral/peri-tumoral tissues a week after the therapy has had the effect. These results support the potential use of o-MWCNTs as antitumoral agents and reveal interesting clues of how to enhance the efficient clearance of in vivo carbon nanotubes.This work has been supported by the Spanish MINECO and European Union FEDER under Projects ref. PI13/01074, PI16/000496, MAT2015-69508-P, the NanoBioApp Network Ref. MINECO-17-MAT2016-81955-REDT, IDIVAL Projects ref. INNVAL15/16, INNVAL 17/11, PREVAL 16/03, and the Raman4clinics BMBS COST Action BM1401