Limosilactobacillus reuteri alleviates proinflammatory T cell-mediated liver injury and transcriptomic changes in immunocompromised mice

Ana Fadhel Alvarez¹Zheng Yin²Beanna Okeugo¹Alexander Banerjee³Meng Luo⁴Christopher M Taylor⁴Salomea Giorgberidze¹Vaishali Harne¹Majji Rambabu⁵Melissa N Munroe¹Stephen TC Wong²Hari Krishna Yalamanchili⁵Suhair Al Salihi³Jon Marc Rhoads¹Yuying Liu^1*

• ¹Department of Pediatrics, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, United States
• ²Systems Medicine and Bioengineering Department, Houston Methodist Neal Cancer Center, Houston, United States
• ³Department of Pathology and Laboratory Medicine, McGovern Medical School, The University of Texas Health Science Center at Houston, Houston, United States
• ⁴Microbial Genomics Resource Group, Department of Microbiology, Immunology and Parasitology, Louisiana State University Health Sciences Center, New Orleans, United States
• ⁵Department of Pediatrics, Neurology, Baylor College of Medicine, Houston, United States

Background: A deficiency of immunosuppressive regulatory T cells, as seen in scurfy (SF) mice or IPEX syndrome in humans, can lead to multiorgan inflammation. Oral administration of probiotic Limosilactobacillus reuteri DSM 17938 prolongs survival and reduces Th1-and Th2-associated inflammation in SF mice. It is unclear how DSM 17938 educated SF-CD4+T cells can modulate T cell-liver communication. Methods: To characterize CD4+T cells from SF mice orally administered with DSM 17938 (Prob-SF-CD4+T cells) and to compare with CD4+T cells from SF mice (SF-CD4+T cells), we adoptively transferred by intraperitoneal (IP) injection cells isolated from SF spleens to lymphocyte-deficient-RAG1KO mice. We then assessed liver histological inflammation and macrophage (MΦ)s, liver sample transcriptomes by RNA-seq, and stool microbiota by 16s rRNA sequencing in RAG1KO mice. Results: Prob-SF-CD4+T cells reduced the incidence and severity of liver inflammation and F4/80+MΦ infiltration caused by transferring SF-CD4+T cells. SF-CD4+T cells up-regulated genes and altered RNA splicing factors and events involved in inflammatory pathways. These included TLR cascades, inflammatory cytokine and death receptor signals. SF-CD4+T cells down-regulated genes linked to metabolism, including mitochondrial function, TCA cycle, lipids and liver detoxification. Prob-CD4+T cell transfer reversed SF-CD4+T cell-induced gene changes in inflammatory and metabolic interactive clusters, while modulating distinct genes involving TLR regulation and cell cycle. CD4+T cell transfer altered gut microbial diversity compared to RAG1KO mice without CD4+T cell transfer. Prob-SF-CD4+T cell transfers exclusively increased relative abundance (RA) of Incertae_sedis and reduced RA of Clostridia_vadinBB60_group in the stool of RAG1KO mice. Conclusions: Inflammatory lymphocytes (CD4+T cells) can perpetuate an exaggerated immune response in the immunologically naïve host. DSM17938 feeding modulated T cells and allowed them to benefit the recipient. We discovered activation of multiple genes and their interactions. Findings suggest that probiotics or probiotic-modulated T cells can be further explored as therapeutic options for autoimmune liver diseases.