Explantation cell culture technique

Embryo cultures may be established from embryos removed from sterilized seeds, ovules, or fruits. The embryos produced from cell culture technique, known as somatic embryos, can be isolated and germinated to provide one plant per explant. Embryo culture can be employed for the rapid production of seedlings from seeds which have a protracted dormancy period. The method has many potential advantages over traditional propagation systems, such as fast turnaround, genetic uniformity, mass production, and propagation of disease-free plants. 

Recent advances in cell and tissue culture techniques provide the potential for evaluation of drug transport or metabolism processes at the placenta. Techniques are available for culturing trophoblasts of both animal and human origin.106 However, our focus here is primarily on human systems. Primary explant and isolated cell cultures of human cytotrophoblasts have been well described 106-109 however, these systems do not form confluent monolayer systems adequate for transcellular transport studies.105... 

Tissue culture A generic phrase often incorrectly used to describe the growth both of small tissue pieces (i.e., organ or explant culture) and of individual cells in vitro most appropriately characterizes the growth or maintenance of explanted tissue or organs, which characterized much of the early scientific period of culture techniques. 

Markland, W., Haddon, L. 1982. An improved technique for the culture of Jerusalem Artichoke (Helianthus tuberosus L.) explants for use in study of xylem differentiation. Plant Cell Reports 1 229-231. 

The protocol presented here describes how to prepare collagen suitable for culturing embryonic and postnatal tissues and how to process it to make a three-dimensional gel in which tissue explants can be manipulated and embedded. The techniques used to isolate and embed tissue are described, as are the ways in which growth and differentiation factors can be presented to tissue explants within these gels. In addition, a summary is provided of the maimer in which such cultures can be manipulated to process by immunohistochemical or in-situ hybridization techniques to examine cell differentiation within tissue explants. 

Subsequent to culture, the patterns of cell differentiation within explants can be examined either by immunohistochemical or in-situ hybridization techniques (Fig. 2). In either case, explants can be sectioned directly in the gel then analyzed or processed for whole-mount labeling. The decision whether to section or process for whole-mount labeling is largely probe dependent. With a strong probe or antibody, whole-mount labeling techniques work well (Fig. 2C). With a weaker probe or antibody, sectioiung is more appropriate (Fig. 2D). 

At this early point, culturists had already demonstrated important concepts i.e., under appropriate conditions cultured cells could survive, move, and proliferate in vitro. These were significant findings in their own right but other equally important questions needed to be addressed before culture acquired credibility as a scientific technique. One of the most important questions was (and, in some cases, still is) whether in vitro conditions were representative of the in vivo environment There persists today healthy concern, and controversy, as to whether in vitro data can be extrapolated to in vivo situations. An early positive position on the relationship issue came as a result of experimental observations on explanted frog tissue function(s) in frog lymph clots in vitro (Harrison, 1907). 

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