Add spaces between the words in the following text: Tissuemodelswithhigherphysiologicalrelevanceareneededtopredicttheefficacyandsafetyofcompoundsbeforeadmittingthemtoclinicaltrials.Recently,standardinvitrocellculturetechniqueshaveevolvedfromtwo-dimensionalmonolayerculturestowardthree-dimensionalmulti-cellularmodels,aimingtomimictheinvivotissuemicroenvironment.
Tissue models with higher physiological relevance are needed to predict the efficacy and safety of compounds before admitting them to clinical trials. Recently, standard in vitro cell culture techniques have evolved from two-dimensional monolayer cultures toward three-dimensional multi-cellular models, aiming to mimic the in vivo tissue microenvironment.