Transplanting fecal material from wild-type mice fed black raspberries alters the immune system of recipient mice.

Transplanting fecal material from wild-type mice fed black raspberries alters the immune system of recipient mice.

By constantly stimulating intestinal immunity, gut microbes play important regulatory roles, and their possible involvement in human physical and mental disorders beyond intestinal diseases suggests the importance of maintaining homeostasis in the gut microbiota. Both transplantation of fecal microbiota and dietary interventions have been shown to restore microbial homeostasis in recipients. In the current study with wild-type mice, we combined these two approaches to determine if transplanting fecal material from mice fed black raspberries (BRB, 5%) altered recipients’ immune system. The donors received a control or 5% BRB diet, and fecal transplantation was performed every other day 15 times into recipients fed control diet. Afterward, we used flow cytometry to analyze populations of CD3+ T, CD4+ T, CD8+ T cells, and NK cells among bone marrow cells, splenocytes, and peripheral blood mononuclear cells (PBMCs) collected from the recipients. We found that BRB-fecal material that contained both fecal microbiota and their metabolites increased NK cell populations among bone marrow cells, splenocytes, and PBMCs, and raised levels of CD8+ T cells in splenocytes. Our findings suggest that fecal transplantation can modulate the immune system and might therefore be valuable for managing a range of physical and mental disorders.

通过持续刺激肠道免疫，肠道微生物发挥着重要的调节作用，它们可能参与肠道疾病以外的人类身心疾病，这表明维持肠道微生物群稳态的重要性。粪便微生物群移植和饮食干预都已被证明可以恢复受体的微生物稳态。在当前对野生型小鼠的研究中，我们结合这两种方法来确定移植喂食黑树莓（BRB，5%）的小鼠的粪便物质是否会改变受体的免疫系统。供体接受对照饮食或5%的BRB饮食，并且每隔一天对接受对照饮食的受体进行15次粪便移植。之后，我们使用流式细胞术分析从受体收集的骨髓细胞、脾细胞和外周血单核细胞（PBMC）中CD3 + T、CD4 + T、CD8 + T细胞和NK细胞的数量。我们发现含有粪便微生物群及其代谢产物的BRB粪便物质增加了骨髓细胞、脾细胞和PBMC中的NK细胞数量，并提高了脾细胞中CD8 + T细胞的水平。我们的研究结果表明，粪便移植可以调节免疫系统，因此可能对管理一系列身心疾病有价值。