Pericytes, as a key cellular part of the blood-brain barrier, play an important role in the maintenance of brain neurovascular unit. These cells participate in brain homeostasis by regulating vascular development and integrity mainly through secreting various factors. Pericytes per se show different restorative properties after blood-brain barrier injury. Upon the occurrence of brain acute and chronic diseases, pericytes provoke immune cells to regulate neuro-inflammatory conditions. Loss of pericytes in distinct neurologic disorders intensifies blood-brain barrier permeability and leads to vascular dementia. The therapeutic potential of pericytes is originated from the unique morphological shape, location, and their ability in providing vast paracrine and juxtacrine interactions. A subset of pericytes possesses multipotentiality and exhibit trans-differentiation capacity in the context of damaged tissue. This review article aimed to highlight the critical role of pericytes in restoration of the blood-brain barrier after injury by focusing on the dynamics of pericytes and cross-talk with other cell types.

Angiogenesis is touted as a fundamental procedure in the regeneration and restoration of different tissues. The induction of de novo blood vessels seems to be vital to yield a successful cell transplantation rate loaded on various scaffolds. Scaffolds are natural or artificial substances that are considered as one of the means for delivering, aligning, maintaining cell connection in a favor of angiogenesis. In addition to the potential role of distinct scaffold type on vascularization, the application of some strategies such as genetic manipulation, and conjugation of pro-angiogenic factors could intensify angiogenesis potential. In the current review, we focused on the status of numerous scaffolds applicable in the field of vascular biology. Also, different strategies and priming approaches useful for the induction of pro-angiogenic signaling pathways were highlighted.

The science of gene therapy has experienced a controversial history. At first, the initial concept that various disorders become curable by gene transferring was very exciting and challengeable. However, the problems and difficulties related to emerging techniques and unwanted side effects seen in some patients who have undergone gene therapy make some questions against the safety of novel molecular medicine approach. In line with this statement, discovery and developing a good bio-vector possessing low toxicity and high efficiency rate are the most important issues in gene therapy field. Introducing exosomes as vectors for gene delivery gives us a new opportunity in gene-based therapy. Exosomes, ranging from 30 to 120 nm in diameter, have unique lipid and protein composition. These nanostructures participate in cell-to-cell cross-talk, regulation of immune system, and the transport of genetic material. Besides the inherent potency of exosomes in gene therapy, a better understanding of their biology, characteristics, production, targeting, and cargo loading still need to be elucidated. In the current review, we exclusively focused on the various facets of exosomes and their importance as a bio-shuttle in gene therapy.