AUTHOR=Nemcova Monika , Seidlova Veronika , Zukal Jan , Dundarova Heliana , Zukalova Katerina , Pikula Jiri TITLE=Performance of bat-derived macrophages at different temperatures JOURNAL=Frontiers in Veterinary Science VOLUME=Volume 9 - 2022 YEAR=2022 URL=https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2022.978756 DOI=10.3389/fvets.2022.978756 ISSN=2297-1769 ABSTRACT=Heterothermy, as a temperature-dependent physiological continuum, may affect host-pathogen interactions through modulation of immune responses. Here, we evaluated proliferation and functional performance of a macrophage cell line established from the greater mouse-eared (Myotis myotis) bat at 8, 17.5 and 37 °C to simulate body temperatures during hibernation, daily torpor and euthermia. Macrophages were also frozen to -20 °C and then examined for their ability to proliferate in the immediate post-thaw period. We show that bat macrophages can proliferate at lower temperatures, though their growth rate is significantly slower than at 37 °C. The cells differed in their shape, size and ability to attach to the plate surface at both lower temperatures, being spheroidal and free in suspension at 8 °C and epithelial-like, spindle-shaped and/or spheroidal at 17.5 °C. While phagocytosis at temperatures of 8 and 17.5 oC amounted to 85.8 and 83.1% of the activity observed at 37 oC, respectively, full phagocytic activity was restored within minutes of translocation into a higher temperature. Bat-derived macrophages were also able to withstand temperatures of -20 °C in a cryoprotectant-free cultivation medium and, in the immediate post-thaw period, became viable and were able to proliferate. Our in vitro data enhance understanding of macrophage biology.