Assessment of Composite Immunotoxicity of Yangtze River Water Extracts Using Multiendpoint In Vitro Bioassays

The immune system is a complex and susceptible network. However, immunotoxicity assessment of environmental matrices remains limited due to the lack of high-throughput detection methods. In this study, an integrated in vitro bioassay combining THP-1 macrophages and Jurkat T cells was employed to evaluate key immunotoxicity endpoints─ including morphology, adhesion, mitochondrial activity, phagocytosis, IL-1β secretion and IL-2 secretion─in surface water extracts from the Yangtze River (China). Our findings revealed complex immunomodulatory effects, characterized by biphasic responses in adhesion, morphology, and cytokine secretion, as well as distinct seasonal variations in morphology change and IL-1β secretion. To enable cross-sample comparability, we applied the CRITIC (Criteria Importance through Intercriteria Correlation) method to weigh six indicators for both immunostimulation and immunosuppression. The results highlighted that macrophage IL-1β secretion and T cell IL-2 secretion were the most influential contributors to immunostimulation and immunosuppression, respectively, underscoring the necessity of incorporating multiple cell types in immunotoxicity assessments. CRITIC scores indicated notable regional differences during the dry season and higher overall immunotoxicity during the wet season. In conclusion, this study achieved a multiendpoint composite assessment of immunotoxicity in Yangtze River surface water, providing a novel methodological tool for basin-scale environmental risk assessment.