Some degrees of difference: impact of in vitro cultivation temperature on mesenchymal stromal cells from species with different body core temperatures.

BACKGROUND: Multipotent mesenchymal stromal cells (MSC) are promising candidates for regenerative therapies in human and animal patients. However, limiting comparability between studies in different species, subtle differences between their MSC occur. Contributing to this, MSC culture protocols are mainly optimized for the human cells. For example, it remains widely neglected that the standard cultivation temperature at 37 °C does not match the body core temperature of several relevant animal species. Therefore, we here investigated growth and viability parameters of primary mesenchymal stromal cells from species with different body core temperatures, namely humans (37 °C) and sheep (38.5 °C), at different cultivation temperatures, including subphysiological, physiological and mild febrile temperatures for each species.

RESULTS: The cells showed the best proliferation characteristics and colony forming potential at the species' respective physiological body core temperature. Mild febrile temperatures altered cell morphologyand compromised colony forming unit potential (p < 0.05). Subphysiological temperatures had no significant effect on colony forming unit potential, but tended to slow proliferation with decreased metabolic activity of the cell cultures (p < 0.05 in human MSC). In addition, subphysiological temperatures increased apoptosis in human MSC (p < 0.05).

CONCLUSIONS: Cultivation temperature impacts on mesenchymal stromal cell viability characteristics. The current study provides a first basis for species-specific temperature adaptation in MSC culture procedures, with relevance to translational animal studies, and possibly also to companion animal MSC treatments.