Intestine Explants in Organ Culture: A Tool to Broaden the Regenerative Studies in Echinoderms

Abstract

The cellular events underlying intestine regrowth in the sea cucumber Holothuria glaberrima have been described by our group. Currently, the molecular and signaling mechanisms involved in this process are being explored. One of the limitations to our investigations has been the absence of suitable cell culture methodologies, required to advance the regeneration studies. An in vitro system, where regenerating intestine explants can be studied in organ culture, was established previously by our group. However, a detailed description of the histological properties of the cultured gut explants was lacking. Here, we used immunocytochemical techniques to study the potential effects of the culture conditions on the histological characteristics of explants, comparing them to the features observed during gut regeneration in our model in vivo. Additionally, the explant outgrowths were morphologically described by phase-contrast microscopy and SEM. Remarkably, intestine explants retain most of their original histoarchitecture for up to 10 days, with few changes as culture time increases. The most evident effects of the culture conditions on explants over culture time were the reduction in the proliferative rate, the loss of the polarity in the localization of proliferating cells, and the appearance of a subpopulation of putative spherulocytes. Finally, cells that migrated from the gut explants could form net-like monolayers, firmly attached to the culture substrate. Overall, regenerating explants in organ culture represent a powerful tool to perform short-term studies of processes associated with gut regeneration in H. glaberrima under controlled conditions.

Primary explants of the postnatal thymus allow the expansion of clonogenic thymic epithelial cells that constitute thymospheres

“…Regenerative medicine offers distinct methodologies that could solve this problem. Primary explant culture is a technique that have allowed the expansion of epithelial cells in several models without using enzymatic reagents and irradiated feeder layer cells [ 12 – 15 ]. Therefore, the objective of this work was to design an easier and efficient methodology using primary thymic explant cultures to obtain clonogenic TECs and thymic interstitial cells (TICs) with high regenerative capacity.…”

The Effects of Short-Chain Fatty Acids in Gut Immune and Oxidative Responses of European Sea Bass (Dicentrarchus labrax): An Ex Vivo Approach

“…However, the lack of adequate in vitro systems to study and understand the physiological processes that occur at the intestine level of several fish species has prompted scientists to find new ways to study these interactions [22]. Thus, innovative systems, like the use of explants (non-disaggregated tissue or organ fragments that have been taken from an organism), are being tested to study the interactions between the host and different compounds or bacteria [9,23].…”