 Altered interplay between gut mucosa and dysbiotic bacteria during HIV infection seems to contribute to chronic immune dysfunction. Manipulation of the intestinal microbiota with nutritional interventions exert limited immunologic effects, but a deep understanding of how these interventions could ameliorate gut dysbiosis and influence health among HIV-infected individuals remain unexplored. In this Phase I clinical trial, 30 HIV-infected subjects on effective ART with evidence of persistent immune dysfunction, indicated by a CD4CD8 ratio1 will be included and randomized to either repeated low-dose oral fecal microbiota transplantation or placebo during 8 weeks. The primary outcome will be safety. Secondary outcomes will include changes in CD4 T cell counts, CD8 T cell counts, CD4CD8 ratio, inflammatory markers, T cell activation and markers of enterocyte barrier function through week 48. Engraftment on host microbiota will be examined using Illumina sequencing of the V3-V4 16S RNA, and changes in bacterial metabolism and in the plasma metabolite fingerprint will be studied by combination of untargeted mass spectrometry and two different and complementary separation techniques in bacterial and plasma samples. 