biostudies-literatureWang YChina Postdoctoral Science FoundationNational Natural Science Foundation of Chinathe Strategic Priority Research Program of the Chinese Academy of Sciencese2120835119https://www.ebi.ac.uk/biostudies/studies/S-EPMC8833202biostudies-literatureUnknown119(6)Changes in population density lead to phenotypic differentiation of solitary and gregarious locusts, which display different resistance to fungal pathogens; however, how to regulate their cellular immune strategies remains unknown. Here, our stochastic simulation of pathogen proliferation suggested that humoral defense always enhanced resistance to fungal pathogens, while phagocytosis sometimes reduced defense against pathogens. Further experimental data proved that gregarious locusts had significantly decreased phagocytosis of hemocytes compared to solitary locusts. Additionally, transcriptional analysis showed that gregarious locusts promoted immune effector expression (<i>gnbp1</i> and <i>dfp</i>) and reduced phagocytic gene expression (<i>eater</i>) and the cytokine tumor necrosis factProceedings of the National Academy of Sciences of the United States of AmericaVariation of TNF modulates cellular immunity of gregarious and solitary locusts against fungal pathogen <i>Metarhizium anisopliae</i>.PMC883320231670420XDB110100002013M530765Yuan SYang PTong XWang YLi LZhao YKang LfalseVariation of TNF modulates cellular immunity of gregarious and solitary locusts against fungal pathogen <i>Metarhizium anisopliae</i>.Changes in population density lead to phenotypic differentiation of solitary and gregarious locusts, which display different resistance to fungal pathogens; however, how to regulate their cellular immune strategies remains unknown. Here, our stochastic simulation of pathogen proliferation suggested that humoral defense always enhanced resistance to fungal pathogens, while phagocytosis sometimes reduced defense against pathogens. Further experimental data proved that gregarious locusts had significantly decreased phagocytosis of hemocytes compared to solitary locusts. Additionally, transcriptional analysis showed that gregarious locusts promoted immune effector expression (<i>gnbp1</i> and <i>dfp</i>) and reduced phagocytic gene expression (<i>eater</i>) and the cytokine tumor necrosis fact2022-01-01T00:00:00Z2022 Feb2026-05-09T14:08:43.702Z2025-04-19T23:35:58.864ZS-EPMC88332023511041310.1073/pnas.2120835119