Table 1.

Table of established in vitro models for hair follicle research.

Model	Main results	Advantages	Limitations	Reference
Spheroid-like 3D cultures	Expression of β-catenin	The ability to restore expression of the markers confirmed by methods such as RT-PCR and immunofluorescence.	Higher costs	[42,46,47]
Monolayer 2D hair follicle models	Adherent DPCs cultured on plastic (2D-style HF model) barely expressed NCAM, versican, and a-SMA proteins	Ease of use, lower cost, and abundant scientific literature surrounding its use	Loss of primary inductive potency of dermal papilla cell (DPC); do not show expression of markers associated with HF inductivity	[43,44]
Animal models	The best model to study HF cycling	A better understanding of pathophysiological processes involved in alopecia	Ethical limitations, human HF growth phases differ in comparison to animals, and growth does not occur in synchronized manner	[45,46]
DPC in microwells	Overexpressing the MR gene Lef-1 in combination with spontaneous DPC spheroid formation in the HSCs showed a significant increase (from 19% to 70%) in the success rate of ex vivo HF formation compared to empty vector-transfected DPCs.	A physiological arrangement of cells in a hair follicle	Difficulties with appropriate selection of growth factors, small molecules, or proliferation enhancers; limitation by resolution in the spatial control of cells	[50]