"Adipose tissue is an important multi-depot and multi-function organ. Each depot exhibits a unique phenotype relative to its anatomical location and specific function. Among adipose depots, the perivascular adipose tissue (PVAT) is a major regulator of blood vessel function due to its proximity to the vasculature and its ability to secrete vasoactive molecules. The comprehensive study of PVAT biology requires in vivo, ex vivo, and reductionist approaches. Adipogenic models of PVAT, where preadipocytes from these tissues are induced to differentiate into adipocytes, are an important reductionist model that can be used to study the perivascular adipocyte. However, the development of PVAT cellular models is challenging because the standardized pharmacological induction of adipogenesis does not have the same efficacy when used across multiple PVAT depots. Different research laboratories have attempted to increase the efficiency of the standard pharmacological adipogenesis induction by pairing it with alternative approaches to cell culture to improve adipogenesis simultaneously such as polymer structures, matrices, and co-cultures. These have been effective in differentiating adipocytes from other visceral adipocytes, but not yet reported to be used in PVAT adipocytes. Another difficulty in adipogenic modeling is that preadipocyte populations in each depot have different adipogenic potential. As not all fibroblast like cells in adipose will differentiate into adipocytes, adipogenic capacity is determined by a population of cells committed to differentiation called adipocyte progenitor cells (APC). These cells, that express a unique profile of specific surface markers, must be isolated from the stromal vascular fraction (SVF) of the adipose. The goal of this thesis was to develop alternative methods to improve the efficiency of current models of adipogenesis in PVAT. We first adapted the use of magnetic activate cell sorting (MCS) to isolate adipocyte progenitor cells (APC). These adipocyte precursors must then be cultured to initiate adipogenesis in order to study mature adipocytes that are phenotypically and functionally similar to primary adipocytes of the same depot. Next, we developed a co-culture method that improved the adipogenesis efficiency and reduced the time required to induce differentiation in a cell culture model of PVAT. Our work provides a method to isolate APC from PVATs and a method using co-culture to differentiate PVAT preadipocytes, both of which are efficient in creating a more accurate depot-specific PVAT model of adipogenesis."--Abstract.
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