Advanced In Vitro Models for Replacement of Animal Experiments

In the last decade there has been an exponential increase in scientific focus given towards enhancing physiological relevance of vitro systems and expanding their applications to support movement replacing, reducing, refining (3Rs) use vivo experimentation. Beyond socio-economic considerations public stakeholders, this also had a substantial impact upon ongoing changes regulation surrounding application animal testing strategies. Despite continuing advancements within field remains constant need develop, enhance implement model order to: (i) deduce potential reduce potentially replace experimentation, as well (ii) progress implementation acceptance by regulatory legislative stakeholders. The intention special issue was bring together wealth expertise knowledge regarding plethora research activities systems, specifically providing current insight into advances made discuss issues being encountered. Introducing topic area are two essays that problems challenges experiments (10.1002/smll.202004182), then how these can be counteracted new methodologies (10.1002/smll.202006298). paper Burden colleagues is further supported expanded reviews authored both Bas et al. (10.1002/smll.202006027) highlights specific requirements for development standardised approaches validation purposes; Halappanavar (10.1002/smll.202007628) non-animal strategies toxicology testing, particularly engineered nanomaterials, focussing adverse outcome pathways. models liver nanomaterial genotoxicology (10.1002/smll.202006055), cardiovascular system assess myocardial infarction (10.1002/smll.202003765) introduced. While Fritsche highlight based on embryonic stem cells induced pluripotent human origin next level assessments (10.1002/smll.202006252). Building expansive different tools available they used efficacy safety 11 original articles multitude with systems. With comparisons continually data sets, its approaches, Ma-Hock (10.1002/smll.202005725) necessary dose setting studies previous relevant lung burden. Further this, demonstrating advantages offered advanced silico nanosafety assessment highlighted Kampfer (10.1002/smll.202004223), Burgum (10.1002/smll.202002551), Chiou (10.1002/smll.202001432), Jagiello (10.1002/smll.202003465), utilising range from (geno)toxicity microscopic evaluation predictive modelling quantitative structure-activity relationship nanomaterials (Nano-QSAR). terms advancing re-creating anatomical structures vitro, work Poventud-Fuentes (10.1002/smll.202004889), Kohl (10.1002/smll.202006012), Lee (10.1002/smll.202004258) expand organ-on-a-chip technologies microfluidic devices. Tang (10.1002/smll.202006050) discusses possibility 3D bioprinting glioblastoma models, Suhito (10.1002/smll.202002436) applies spheroid cultures create nanostructured platform facilitates electrochemical detection cellular cancer cells. These papers possibilities associated technologies. final article published takes another direction Hsu (10.1002/smll.202006091) reporting effects oxygen microenvironment matrix composition endothelial cell network formation, example alter variables more closely mimic physiology. Recreating nature body discussed concept Llewellyn (10.1002/smll.202004630) whereby simulate acellular gut micro-environments transformation such biological compartments, toxicological outcomes gastro-intestinal tract liver. This therefore qualities provide understanding mechanisms toxicology, or interactions xenobiotics tissue/organ. It progresses introducing state art (e.g. microfluidics, organ-on-a-chip, re-creation components). introductions at beginning issue, scene ‘alternative models’ collection provides fantastic basis people introduced field, but experienced scientist.