A zebrafish immunodeficiency model induced by the combination of Tacrolimus and Everolimus for rapid assessment of immune-enhancing agents

A methodology for the assessment of the immune-enhancing effects of various substances within a period of 5 days was reported. Experimentally, it was determined that the continuous treatment of Tacrollimus (0.5 ng/mL) and Everolimus (5 g/mL) on zebrafish from 48 hpf to 120 hpf was sufficient to establish an immunodeficient model. The results showed that the model exhibited a significant reduction in the number of immune cells (thymocytes, myeloid cells, and macrophages) and a greater than 50% decrease in the expression of immune-related genes (itk, hexb, cpa5, isg15, rsad2). Astragalus powder can effectively increase the content of thymic T cells and macrophages, but its effect on myeloid cells is limited. Ganoderma lucidum spore powder had the most obvious influence on macrophages, with limited impact on thymus cells and myeloid cells. Royal jelly showed a significant effect on thymus T cells and macrophages, but its effect on myeloid cells was limited. Bailing capsule can significantly increase the content of myeloid cells and thymus T cells, while its effect on macrophages was limited. The study showed immune indexes varied in recovery with different immunomodulators versus the model group, suggesting they may act via distinct mechanisms. Summary StatementA robust immune system is vital to overall health and quality of life. Recent years have witnessed surging development of immune-boosting pharmaceuticals, nutraceuticals, and functional foods. However, an easy-to-use, rapid and intuitive immunity assessment framework is still missing. Here, a methodology for the assessment of the immune-enhancing effects of various substances within a period of 5 days was reported.