In Vitro Thermal Effects on Embryonic Cells of Endangered Hawksbill TurtleEretmochelys imbricata

Abstract

The hawksbill turtle is an ectotherm, whose sex is determined by temperature during embryonic development. This study aimed to determine whether embryonic hawksbill turtle cells respond differently to temperature than mammalian cells. Embryonic hawksbill turtle cells were established in culture, and thermal effects on these cells were investigated in vitro. Cells were maintained in Dulbecco's Modified Eagle Medium supplemented with non-essential amino acids, vitamin solution, sodium pyruvate, and 10% fetal bovine serum at 33°C and cell proliferation occurred at 25-33°C. When cells were incubated at 37°C (the temperature of mammalian cell culture) for 24 h, cell growth was completely inhibited. This growth inhibition was evidently recovered by changing the incubation temperature back to 33°C. Expression of heat shock protein was found to increase with elevating culture temperature from 25 to 33°C.

Establishment, Characterization, and Toxicological Application of Loggerhead Sea Turtle (Caretta caretta) Primary Skin Fibroblast Cell Cultures

“…Previous literature suggests that temperatures at or slightly above the source animals’ preference are suitable for reptilian cell culture work and that an optimal temperature would occur between approximately 23 and 37 °C for sea turtles. − Our findings indicated that 30 °C is the preferred growth temperature for primary loggerhead fibroblast sea turtle skin cultures and corresponds to the 28–30 °C rearing temperature at the NOAA Sea Turtle Facility. Immortal green sea turtle cells are reported to grow well at 25–30 °C, primary hawksbill and olive ridley sea turtle cells at 26 °C, and loggerhead sea turtle leukocytes at 30 °C, though proliferation was reported at a wide range of other temperatures. ,,,− ,, …”

“…Immortal green sea turtle cells are reported to grow well at 25−30 °C, primary hawksbill and olive ridley sea turtle cells at 26 °C, and loggerhead sea turtle leukocytes at 30 °C, though proliferation was reported at a wide range of other temperatures. 12,21,33,[22][23][24][25]29,31 Reptilian cell cultures reported in the literature utilized cell medium designed for mammalian cells. Multiple options have been examined for sea turtle cell cultures, including medium 199, minimum essential medium (MEM), Dulbecco's modified Eagle medium (DMEM), Leibovitz L-15, F-10 nutrient mix, F-12 nutrient mix, basal medium Eagle (BME), and RPMI 1640.…”

“…Traditional invasive or lethal toxicology testing methods are very seldom suitable to endangered species research. , For this reason, toxicology research in sea turtles so far has focused mainly on contaminant burden analyses in tissues, − with rare forays into animal dosing , or egg exposure studies. , Immortal cell lines were developed for virology in the green sea turtle (Chelonia mydas) almost exclusively from animals affected by fibropapillomatosis − or from embryos . Pioneering in vitro toxicity testing in sea turtles used these cell lines to examine the effect of organochlorines on cytochrome P450 aromatase and test metal sensitivity. , Primary skin fibroblasts and embryonic cultures were recently established and partially characterized in the hawksbill sea turtle (Eretmochelys imbricata) and olive ridley sea turtle (Lepidochelys olivacea). − Primary skin fibroblasts from one hawksbill sea turtle were subsequently evaluated for chromium toxicity and a preliminary assessment of thermal effects on heat shock protein expression was conducted in embryonic cultures in the same species . Additionally, leukocytes have been cultured from loggerhead turtles; , however, there are several major differences in the culture of blood cells versus adherent cells reported here.…”