In vitro spheroid model of placental vasculogenesis: does it work?

Abstract

Placental vascular development begins very early in pregnancy and is characterized by construction of a primitive vascular network in a low-oxygen environment. In vitro three-component assays of this process are scarce. In this study, a complex three-dimensional spheroid model for in vitro studies of placental vasculogenesis with regard to cell-cell interactions between cytotrophoblasts (CTs), villous stromal cells and endothelial precursor cells was established. Microscopic and immunohistochemical analyses of the spheroids showed structural and differentiation patterns resembling the structure and differentiation of early placental chorionic villous tissue (in regard to the expression of multiple markers cytokeratin-7, vimentin, CD34, CD31). The authenticity of this model to in vivo events allowed investigation of placental vascular development and trophoblast invasion under physiological and pathological conditions. Particularly enhanced spheroidal expression of SDF-1a and its receptor CXCR4, the major chemokine system in embryonic vasculogenesis, in a low-oxygen environment was detected. In addition, our model confirmed previously described invasive phenotype of trophoblasts through collagen under low-(physiologic), but not high-(pathologic) oxygen concentrations. Therefore, the three-dimensional spheroid model consisting of major placental cell types proved to be an appropriate system to investigate early placental vessel development under both physiological and pathological conditions.

Three-dimensional culture systems in cancer research: Focus on tumor spheroid model

“…MCTS are constructed from tumor cells alone or in combination with other cell types with or without scaffolds (Baal et al , 2009) (Figure 1C). Tumor spheroids display various morphologies depending on the inherent nature of the cell and the culture conditions (Figure 2A).…”

“…Additionally, 2D-cultured cells are stretched and undergo cytoskeletal rearrangements acquiring artificial polarity, which in turn causes aberrant gene and protein expression (Cukierman et al , 2001; Nickerson et al , 2001; Kelm et al , 2003; Delarue et al , 2014). In contrast, three-dimensional (3D) culture systems offer the unique opportunity to culture cancer cells alone or with various cell types in a spatially relevant manner, encouraging cell-cell and cell-matrix interactions that closely mimic the native environment of tumors (Baal et al , 2009). These interactions cause the 3D-cultured cells to acquire morphological and cellular characteristics relevant to in vivo tumors (Ma et al , 2012).…”

Human placenta-derived Wnt-5a induces the expression of ICAM-1 and VCAM-1 in CD133+CD34+-hematopoietic progenitor cells

“…Trophoblast and stromal cells were isolated from placental tissues of early gestation (between week 4 and 10 p.c.) [21]. Extravillous trophoblast cells were excluded via macroscopic visual tissue sampling: Villous trees were collected from early first trimester placentae, whilst third trimester cotyledons were dissected and the amnion, chorionic plate and decidua were discarded.…”

“…Trophoblast and stromal cells were isolated using anti-CD326 antibody-conjugated magnetic microbeads and MACS system. Anti-CD326 has been established as a specific membrane-bound cell marker [21,22], and it is essential for placental development in mice [23]. The positive fraction (CD326 + cells) consists of trophoblast cells and the negative fraction (CD326 À cells) consists of stromal cells.…”

α‐Tocopheryl phosphate—An activated form of vitamin E important for angiogenesis and vasculogenesis?

“…For these experiments, it may be necessary to use fertilized eggs from vitamin E deficient hens as endogenous levels of vitamin E may already lead to full angiogenesis [114]. Alternative models for angiogenesis could also be used such as the in vitro spheroid model for placental vasculogenesis [115], angiogenesis in zebrafish developing embryos [116], or the three dimensional angiogenesis model in rat aortic rings [117] or in human fat tissues [118].…”