Figure 4. Diet-associated fat pathology is transferable to naïve animals using purified T-lymphocytes.

Adoptive transfer of purified CD4+ cells from C57BL/6 wild type donor mice eating probiotics into C57BL/6 Rag2-null mice was sufficient to significantly reduce recipient body fat depots such as subcutaneous fat, as well as ameliorate abdominal fat pathology (a). Control diet-fed mice used as donors for lymphocyte transfer experiments showed IL10-dependent L.reuteri benefits including significantly less CLS in their abdominal fat (b). This immune-mediated protection requires Il10, as adoptive transfer of CD4⁺ cells from probiotic-fed Il10-deficient donors did not protect the recipient mice from obesity and associated fat pathology (c). Purified wild type CD4⁺ FoxP3⁺ Treg cells from mice eating L. reuteri were sufficient for beneficial effects in Rag2-null recipient mice rescuing them from obesity-associated pathology (d). Skin and fat histology: Hematoxylin and eosin. Bars skin = 250 µm, edididymal fat = 50 µm.