Federal Research Center of Fundamental and Translational Medicine, The Federal State Budget Scientific Institution, Siberian Branch of the Russian Academy of Sciences, 2, Timakova St., Novosibirsk 630117, Russia.
Institute of Molecular and Cellular Biology, Russian Academy of Sciences, Siberian Branch, Novosibirsk 630090, Russia.
Viruses. 2023 Nov 29;15(12):2350. doi: 10.3390/v15122350.
SARS-CoV-2 can enter the environment from the feces of COVID-19 patients and virus carriers through untreated sewage. The virus has shown the ability to adapt to a wide range of hosts, so the question of the possible involvement of aquafauna and animals of coastal ecosystems in maintaining its circulation remains open.
the aim of this work was to study the tropism of SARS-CoV-2 for cells of freshwater fish and reptiles, including those associated with aquatic and coastal ecosystems, and the effect of ambient temperature on this process. In a continuous cell culture FHM (fathead minnow) and diploid fibroblasts CGIB (silver carp), SARS-CoV-2 replication was not maintained at either 25 °C or 29 °C. At 29 °C, the continuous cell culture TH-1 (eastern box turtle) showed high susceptibility to SARS-CoV-2, comparable to Vero E6 (development of virus-induced cytopathic effect (CPE) and an infectious titer of 7.5 ± 0.17 log TCID/mL on day 3 after infection), and primary fibroblasts CNI (Nile crocodile embryo) showed moderate susceptibility (no CPE, infectious titer 4.52 ± 0.14 log TCID/mL on day 5 after infection). At 25 °C, SARS-CoV-2 infection did not develop in TH-1 and CNI.
our results show the ability of SARS-CoV-2 to effectively replicate without adaptation in the cells of certain reptile species when the ambient temperature rises.
SARS-CoV-2 可以通过未经处理的污水从 COVID-19 患者和病毒携带者的粪便进入环境。该病毒已显示出适应广泛宿主的能力，因此，水生动物和沿海生态系统中的动物可能参与维持其循环的问题仍然存在。
本工作的目的是研究 SARS-CoV-2 对淡水鱼和爬行动物细胞的嗜性，包括与水生和沿海生态系统相关的细胞，以及环境温度对该过程的影响。在连续细胞培养 FHM（胖头鱼）和二倍体成纤维细胞 CGIB（白鲢）中，SARS-CoV-2 复制均不能在 25°C 或 29°C 下维持。在 29°C 时，连续细胞培养 TH-1（东部箱龟）对 SARS-CoV-2 表现出高易感性，与 Vero E6（病毒诱导的细胞病变效应（CPE）的发展和 3 天后的感染）相当，且传染性滴度为 7.5±0.17logTCID/mL，原代成纤维细胞 CNI（尼罗河鳄胚胎）表现出中度易感性（无 CPE，感染后第 5 天的传染性滴度为 4.52±0.14logTCID/mL）。在 25°C 时，TH-1 和 CNI 中未发生 SARS-CoV-2 感染。
我们的结果表明，当环境温度升高时，SARS-CoV-2 在某些爬行动物物种的细胞中无需适应即可有效复制。
