Reduced microbial diversity in adult survivors of childhood acute lymphoblastic leukemia and microbial associations with increased immune activationOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
Researchers compared anal microbiota composition between adult survivors of childhood acute lymphoblastic leukemia (ALL, n = 73) and healthy controls (n = 61). Survivors were 5 or more years past treatment completion, with a median 18.5 years since treatment cessation.
How was it studied?
Anal swab samples underwent 16S rRNA gene sequencing (V4 region) on the Illumina MiSeq platform, with diversity and taxonomic differences assessed via QIIME and LEfSe analysis. T cell activation (HLA-DR+CD4+ and HLA-DR+CD8+) was measured by flow cytometry, and plasma IL-6 and CRP were measured by ELISA and clinical assay.
What did they find?
Survivors had significantly reduced microbial diversity (Chao1, observed OTUs, phylogenetic distance) despite being asymptomatic. Their microbiota was enriched for Actinobacteria, including genus Corynebacterium, and depleted of Faecalibacterium. These taxa correlated with plasma IL-6, CRP, and HLA-DR+CD4+ and HLA-DR+CD8+ T cell activation, established markers of inflammation and immune activation.
Why it matters
The findings link persistent gut dysbiosis to chronic immune activation years after childhood cancer treatment ends. The authors suggest interventions that restore microbial diversity could help reduce inflammation and prevent late effects like obesity and type 2 diabetes in survivors.