Author
Eric R. Littmann
Other affiliations: Kettering University, University of Texas MD Anderson Cancer Center, University Hospital Regensburg ...read more
Bio: Eric R. Littmann is an academic researcher from University of Chicago. The author has contributed to research in topics: Transplantation & Microbiome. The author has an hindex of 22, co-authored 42 publications receiving 4038 citations. Previous affiliations of Eric R. Littmann include Kettering University & University of Texas MD Anderson Cancer Center.
Papers
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TL;DR: It is determined that Clostridium scindens, a bile acid 7α-dehydroxylating intestinal bacterium, is associated with resistance to C. difficile infection and, upon administration, enhances resistance to infection in a secondary bile Acid dependent fashion.
Abstract: The gastrointestinal tracts of mammals are colonized by hundreds of microbial species that contribute to health, including colonization resistance against intestinal pathogens. Many antibiotics destroy intestinal microbial communities and increase susceptibility to intestinal pathogens. Among these, Clostridium difficile, a major cause of antibiotic-induced diarrhoea, greatly increases morbidity and mortality in hospitalized patients. Which intestinal bacteria provide resistance to C. difficile infection and their in vivo inhibitory mechanisms remain unclear. Here we correlate loss of specific bacterial taxa with development of infection, by treating mice with different antibiotics that result in distinct microbiota changes and lead to varied susceptibility to C. difficile. Mathematical modelling augmented by analyses of the microbiota of hospitalized patients identifies resistance-associated bacteria common to mice and humans. Using these platforms, we determine that Clostridium scindens, a bile acid 7α-dehydroxylating intestinal bacterium, is associated with resistance to C. difficile infection and, upon administration, enhances resistance to infection in a secondary bile acid dependent fashion. Using a workflow involving mouse models, clinical studies, metagenomic analyses, and mathematical modelling, we identify a probiotic candidate that corrects a clinically relevant microbiome deficiency. These findings have implications for the rational design of targeted antimicrobials as well as microbiome-based diagnostics and therapeutics for individuals at risk of C. difficile infection.
1,413 citations
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TL;DR: It is demonstrated that increased representation of bacteria belonging to the Bacteroidetes phylum is correlated with resistance to the development of checkpoint-blockade-induced colitis, and a paucity of genetic pathways involved in polyamine transport and B vitamin biosynthesis is associated with an increased risk of colitis.
Abstract: The composition of the intestinal microbiota influences the development of inflammatory disorders. However, associating inflammatory diseases with specific microbial members of the microbiota is challenging, because clinically detectable inflammation and its treatment can alter the microbiota's composition. Immunologic checkpoint blockade with ipilimumab, a monoclonal antibody that blocks cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) signalling, is associated with new-onset, immune-mediated colitis. Here we conduct a prospective study of patients with metastatic melanoma undergoing ipilimumab treatment and correlate the pre-inflammation faecal microbiota and microbiome composition with subsequent colitis development. We demonstrate that increased representation of bacteria belonging to the Bacteroidetes phylum is correlated with resistance to the development of checkpoint-blockade-induced colitis. Furthermore, a paucity of genetic pathways involved in polyamine transport and B vitamin biosynthesis is associated with an increased risk of colitis. Identification of these biomarkers may enable interventions to reduce the risk of inflammatory complications following cancer immunotherapy.
701 citations
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TL;DR: The results indicate that the intestinal microbiota may be an important factor in the success or failure in allo-HSCT, and the diversity of the intestine microbiota at engraftment is an independent predictor of mortality in recipients.
671 citations
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TL;DR: It is concluded that increased abundance of commensal bacteria belonging to the Blautia genus is associated with reduced lethal GVHD and improved overall survival.
532 citations
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Memorial Sloan Kettering Cancer Center1, Duke University2, University Hospital Regensburg3, Hokkaido University4, University of Cantabria5, University of Texas MD Anderson Cancer Center6, University of Regensburg7, Autonomous University of Madrid8, University Medical Center9, University of Chicago10
TL;DR: In this article, the relationship between microbiota composition and clinical outcomes after allogeneic hematopoietic-cell transplantation has been described in single-center studies in the US.
Abstract: Background Relationships between microbiota composition and clinical outcomes after allogeneic hematopoietic-cell transplantation have been described in single-center studies. Geographic v...
360 citations
Cited by
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French Institute of Health and Medical Research1, Institut Gustave Roussy2, Université Paris-Saclay3, Pierre-and-Marie-Curie University4, Paris Diderot University5, Memorial Sloan Kettering Cancer Center6, University of Orléans7, Paris Descartes University8, Cornell University9, Aix-Marseille University10
TL;DR: It is found that primary resistance to ICIs can be attributed to abnormal gut microbiome composition, and Antibiotics inhibited the clinical benefit of ICIs in patients with advanced cancer.
Abstract: Immune checkpoint inhibitors (ICIs) targeting the PD-1/PD-L1 axis induce sustained clinical responses in a sizable minority of cancer patients. We found that primary resistance to ICIs can be attributed to abnormal gut microbiome composition. Antibiotics inhibited the clinical benefit of ICIs in patients with advanced cancer. Fecal microbiota transplantation (FMT) from cancer patients who responded to ICIs into germ-free or antibiotic-treated mice ameliorated the antitumor effects of PD-1 blockade, whereas FMT from nonresponding patients failed to do so. Metagenomics of patient stool samples at diagnosis revealed correlations between clinical responses to ICIs and the relative abundance of Akkermansia muciniphila Oral supplementation with A. muciniphila after FMT with nonresponder feces restored the efficacy of PD-1 blockade in an interleukin-12-dependent manner by increasing the recruitment of CCR9+CXCR3+CD4+ T lymphocytes into mouse tumor beds.
3,258 citations
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TL;DR: Clinical studies are beginning to define these factors as immune profiles that can predict responses to immunotherapy, suggesting that a broader view of cancer immunity is required.
Abstract: Immunotherapy is proving to be an effective therapeutic approach in a variety of cancers. But despite the clinical success of antibodies against the immune regulators CTLA4 and PD-L1/PD-1, only a subset of people exhibit durable responses, suggesting that a broader view of cancer immunity is required. Immunity is influenced by a complex set of tumour, host and environmental factors that govern the strength and timing of the anticancer response. Clinical studies are beginning to define these factors as immune profiles that can predict responses to immunotherapy. In the context of the cancer-immunity cycle, such factors combine to represent the inherent immunological status - or 'cancer-immune set point' - of an individual.
3,145 citations
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TL;DR: In this article, a new method for metagenomic biomarker discovery by way of class comparison, tests of biological consistency and effect size estimation is described and validated, which addresses the challenge of finding organisms, genes, or pathways that consistently explain the differences between two or more microbial communities.
Abstract: This study describes and validates a new method for metagenomic biomarker discovery by way of class comparison, tests of biological consistency and effect size estimation. This addresses the challenge of finding organisms, genes, or pathways that consistently explain the differences between two or more microbial communities, which is a central problem to the study of metagenomics. We extensively validate our method on several microbiomes and a convenient online interface for the method is provided at http://huttenhower.sph.harvard.edu/lefse/.
3,060 citations
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TL;DR: Examination of the oral and gut microbiome of melanoma patients undergoing anti-programmed cell death 1 protein (PD-1) immunotherapy suggested enhanced systemic and antitumor immunity in responding patients with a favorable gut microbiome as well as in germ-free mice receiving fecal transplants from responding patients.
Abstract: Preclinical mouse models suggest that the gut microbiome modulates tumor response to checkpoint blockade immunotherapy; however, this has not been well-characterized in human cancer patients. Here we examined the oral and gut microbiome of melanoma patients undergoing anti-programmed cell death 1 protein (PD-1) immunotherapy (n = 112). Significant differences were observed in the diversity and composition of the patient gut microbiome of responders versus nonresponders. Analysis of patient fecal microbiome samples (n = 43, 30 responders, 13 nonresponders) showed significantly higher alpha diversity (P < 0.01) and relative abundance of bacteria of the Ruminococcaceae family (P < 0.01) in responding patients. Metagenomic studies revealed functional differences in gut bacteria in responders, including enrichment of anabolic pathways. Immune profiling suggested enhanced systemic and antitumor immunity in responding patients with a favorable gut microbiome as well as in germ-free mice receiving fecal transplants from responding patients. Together, these data have important implications for the treatment of melanoma patients with immune checkpoint inhibitors.
2,791 citations
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TL;DR: The wide range of immune-related adverse effects associated with immune checkpoint blockade can complicate this effective therapy and limit its use in patients with cancer.
Abstract: Side Effects of Immune Checkpoint Blockade The wide range of immune-related adverse effects associated with immune checkpoint blockade can complicate this effective therapy and limit its use in patients with cancer. This review surveys the adverse effects and their management.
2,658 citations