From in vitro Experiments to in vivo and Clinical Studies; Pros and Cons

Abstract

Biomedical investigators use different methods including experimental animals, tissue, and cell cultures as well as computational simulations and clinical studies finding the ways to treat human diseases and disorders. All the mentioned procedures have their own advantages and disadvantages. For instance although animal models provide some drawbacks like difference in biokinetics parameters or extrapolation of results to human, they are more reliable than in vitro tests. The disadvantage of the in vitro procedures is that they are mostly performed on cancerous cell lines that have a substantially abnormal function. Furthermore, although in vitro models are fruitfully used in biological fields, finding an end point, the initial aim of chemical attack, and extrapolation of the effects to the human are some real weaknesses. Absence of biokinetics in in vitro methods may lead to a misinterpretation of the data. The present review has criticized the pros and cons of both methods, especially in the fields of pharmacology, toxicology, and medical sciences.

Topographic characterization of multispecies biofilms growing on dental implant surfaces: An in vitro model

“…However, this study has clear limitations due to its in vitro design, mainly derived from the differences in the microenvironment with the oral cavity (lack of crevicular fluid, host response, etc.) and the limited selection of only six representative bacteria, compared with the heterogeneity of the oral microbiome (Saeidnia, Manayi, & Abdollahi, ). Although in vivo biofilm development on enamel chips or disks may share similarities with the patient's dental plaque, this in vitro biofilm model has used a defined consortium of bacterial species, which may be valid and highly reproducible for these bacterial communities, but may be different to others, considering the heterogeneity of the oral microbiome (Ammann, Bostanci, Belibasakis, & Thurnheer, ; B. Guggenheim, Shapiro, Gmur, & Guggenheim, ; Sanchez et al, ).…”

“…TA B L E 2 Coefficient of variation (CV) values obtained for whole dental implants (WDIs) (n = 18) and hydroxyapatite disks (HA) (n = 3), titanium disks (Ti) (n = 3), zirconium disks (Zn) (n = 3) (Sanchez et al, 2014) for each bacteria employed in the model However, this study has clear limitations due to its in vitro design, mainly derived from the differences in the microenvironment with the oral cavity (lack of crevicular fluid, host response, etc.) and the limited selection of only six representative bacteria, compared with the heterogeneity of the oral microbiome (Saeidnia, Manayi, & Abdollahi, 2015).…”

Biological effects of carbon black nanoparticles are changed by surface coating with polycyclic aromatic hydrocarbons

“…However, if cell lines lack specific pathways that are important for toxic effects, their value for predicting in vivo toxicity is limited [84]. …”

“…The reason for these differences was most likely that some cell lines were more sensitive to the toxic effects of the PAHs, whereas others were more sensitive to changes in surface area. An in vivo experiment in which all target cell types are present is therefore in principle better suited to detect effects [84]. However, in a single in vivo experiment, only a limited number of parameters can be determined.…”

Acidotoxicity via ASIC1a Mediates Cell Death during Oxygen Glucose Deprivation and Abolishes Excitotoxicity

“…Despite these advantages over other in vitro approaches to monitor cell death, we acknowledge that the slice preparation differs from the in vivo scenario. 51,52 However, the microperfusion approach gives superior control over the extracellular environment that could not be achieved in vivo. Here we show that LDH release during OGD or low pH insult reaches a maximum peak and then subsides.…”