Characteristic analysis of Syrian golden hamster models infected by different strains of SARS-CoV-2
10.13200/j.cnki.cjb.004706
- VernacularTitle:严重急性呼吸综合征冠状病毒2不同毒株感染叙利亚金黄地鼠模型的特征分析
- Author:
Zhifeng SONG
- Publication Type:Journal Article
- Keywords:
Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2);
Syrian golden hamster;
Infection modeling;
Characteristic analysis
- From:
Chinese Journal of Biologicals
2026;39(05):513-522+533
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo compare the characteristics of Syrian golden hamsters infected by different severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) strains and clarify the key indicators of golden hamster models infected by different strains, so as to provide experimental basis for evaluating the protective effects of vaccines or drugs developed against different SARS-CoV-2 strains.MethodsThe SARS-CoV-2 prototype strain, BF.7.14 and JN.1 strains were respectively used to nasally infect 6-8-week-old Syrian golden hamsters with high doses(10~(4.) ~5 TCID_(50)/0. 1 mL) and low doses(10~3 TCID_(50)/0. 1 mL),and 12 golden hamsters for each group. Clinical symptoms and weight changes of infected animals were monitored at different time points after virus challenge(days 3, 5, 7 and 14). Heart, liver, spleen, lung, kidney, small intestine and nasal conchae tissues were collected for viral nucleic acid quantification, viral titer determination and histopathological analysis.ResultsNo obvious clinical symptoms were observed after the three strains infected golden hamsters. In the prototype strain group, significant weight loss occurred, and the weight reduction in male individuals was more significant than that in female individuals. The average body weight of males decreased by about 7% and that of females increased by 1. 9% on the 5 th day after infection. The weight fluctuation range of the BF.7.14 and JN.1 infection groups was significantly lower than that of the prototype strain group. The body weights of the animals in the prototype strain, BF.7.14, and JN.1 infection groups increased by 3%, 6. 6% and 7. 8% respectively on the 5 th day after infection. After the three strains infected golden hamsters, high levels of viral RNA could be detected in the lung and nasal conchae tissues, followed by the spleen, small intestine, kidney,heart and liver tissues. Infectious viruses could be detected in lung tissue. Histopathology revealed that all strains of infection caused lung tissue damage. Typical lesions included widened lung interstitium, inflammatory cell infiltration and focal hemorrhage, among which the pathological damage caused by the prototype strain was the most severe. The key indicators were mainly reflected in three dimensions: body weight, viral load and pathological damage. The core difference lied in the gradient difference of pathogenicity intensity. The pathogenicity of the prototype strain was significantly stronger than that of the BF.7.14 and JN.1 strains. Physical sign indicators: Weight change was the core difference point. The degree of weight loss in the prototype strain group was significantly higher than that in the BF.7.14 and JN.1 infection groups. Viral load indicators: There were significant differences in replication ability and tissue tropism. The prototype strain group had a significantly higher replication and infection ability in lung and nasal conchae tissues than the BF.7.14 and JN.1 infection groups, and possessed a persistent infection ability in the body. Pathological damage indicators: The degree of damage showed a significant gradient, with the degree of pathological damage caused by the prototype strain, BF.7.14 and JN.1 gradually decreasing.ConclusionAfter the SARS-CoV-2 prototype strain, BF.7.14 and JN.1 strains infected Syrian golden hamsters, viral nucleic acids could all be detected in multiple tissues. However, the in vivo replication ability of the prototype strain was significantly stronger than that of the two variant strains, and the pathological damage it caused was more severe and lasted longer. The pathogenicity of BF.7.14 and JN.1 strains is relatively weak, and the lung injury is mainly characterized by early localized inflammation. The prototype strain of SARS-CoV-2 and its variant strains in the golden hamster model have different infection characteristics. This study has established golden hamster models infected with different strains, providing an experimental basis for the evaluation of vaccines or drugs developed against different strains of SARSCoV-2.
