Mucosal Immunity

Recurrence of primary glomerulonephritis in the post-transplant period has been described in the literature but the risk remains poorly quantified and its impact on allograft outcomes and implications for subsequent transplants remain under-examined.

Studying long noncoding RNAs (lncRNAs) may improve diagnosis and treatment of inflammatory bowel disease (IBD). These RNAs are found between genes in DNA regions previously thought to be “junk,” and have recently been shown to be important in development of various diseases.

While the vertebrate microbiota is critical to the normal function of many host traits, hosts may expend a large amount of energy to constrain and interface with their microbiota via their immune system to avoid the high fitness costs associated with gut dysbiosis, pathobionts, and opportunistic...

Seasonal influenza vaccines are typically less than 50 percent effective, according to Centers for Disease Control and Prevention studies.

To study the current evidence on the role of immunotherapy in IVF and in the management
of recurrent pregnancy loss (RPL).

The requirement for delivery by injection is currently a limitation for the use of biologic drugs such as antibodies. In this Review, Mitragotri and colleagues discuss advances made in non-invasive drug delivery for biologics, including the transdermal, oral and inhalation routes, highlighting...

Role of eosinophils in airway inflammation of chronic obstructive pulmonary disease Donald P Tashkin,1 Michael E Wechsler2 1Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA; 2Department of Medicine, National Jewish Health, Denver, CO, USA Abstract: COPD is a...

Canadian Journal of Gastroenterology and Hepatology is a peer-reviewed, Open Access journal that publishes original research articles, review articles, and clinical studies in all areas of gastroenterology and hepatology.

In coeliac disease, ingestion of gluten induces the production of transglutaminase 2 (TG2)-targeted autoantibodies by TG2-specific plasma cells present at high frequency in the small intestinal mucosa in untreated disease.

Introduction: We have previously reported that clinically relevant, dramatic reductions occur in intestinal bacterial diversity during allogeneic hematopoietic stem cell transplant (allo-HSCT). These are likely attributable to antibiotic exposure, nutritional alterations, and intestinal mucosa injury from high-dose chemotherapy. Patients undergoing autologous hematopoietic stem cell transplantation (AHCT) also receive antibiotics and experience nutritional alterations due to mucositis and other gastrointestinal toxicities. We hypothesized that the pattern of dysbiosis seen in AHCT patients would reflect the changes in allo-HSCT patients. Here, we present a novel analysis of microbiota diversity in AHCT patients from two independent institutions. Methods: We retrospectively identified a cohort of 365 patients (median age 60 years) who underwent AHCT for treatment of hematologic malignancy between May 2009 to February 2018 at two large-volume transplant centers in the US. The population was diverse in terms of histology, conditioning regimens and remission status prior to transplant, with 179 (49%) patients diagnosed with multiple myeloma, 153 (42%) patients diagnosed with lymphoma, and 33 (9%) patients with other diseases. Stool samples from the selected patients were collected approximately weekly during inpatient hospitalization. Sequencing of the V4-V5 region of the bacterial 16S rRNA genes from all samples was performed on the Illumina platform at a central site. Microbial diversity was measured by the Simpson reciprocal a-diversity index (S). We defined the pre-AHCT period as days -10 to 0, and computed median values for patients with multiple samples within that period. We additionally defined monodomination of the microbiota as a single operational taxonomic unit comprising >30% of bacterial abundance. For comparison, we sequenced samples from 17 healthy volunteers and used a public dataset of sequences from 313 healthy volunteers from the NIH Human Microbiome Project (HMP). Median pre-transplant microbial diversity in the healthy patient and AHCT groups was compared by a pairwise Wilcox test to a retrospective cohort of allo-HSCT patients. Results: We evaluated 857 samples from 365 adult patients undergoing AHCT, with 316 patients from Memorial Sloan Kettering Cancer Center (MSKCC) and 49 patients from Duke University Medical Center (DUMC). Median pre-transplant diversity in AHCT patients from both centers was significantly lower than in normal controls (Fig 1A) (HMP vs MSKCC AHCT, S=12.05 vs. 9.19, p<0.005; HMP vs DUMC AHCT, S=12.05 vs 6.91, p<0.005) and reduced in both AHCT patients and allo-HSCT patients (MSKCC AHCT vs MSKCC allo-HSCT, S = 12.05 vs 8.74, p=0.53). In samples taken from days -10 to +30 after transplant, diversity decreased comparably after AHCT and allo-HSCT across both centers, while AHCT patients demonstrated a more rapid recovery at day +30 compared to allo-HSCT patients (Fig 1B). Finally, monodominance was observed in the samples (Fig 1C), with Streptococcus as the most common genus. The cumulative incidence of intestinal domination by any organism was >50% by day 0 and was >75% by day +14. Conclusion: Microbial diversity is reduced prior to transplant in both AHCT and allo-HSCT patients. Loss of diversity after AHCT occurs across centers and the degree of injury is comparable to the dysbiosis in allo-HSCT patients. Preliminary analysis suggests that lower diversity may correlate with worse progression-free survival (PFS) in myeloma patients in our diverse AHCT cohort. Given the known associations of alterations in microbiota composition with toxicities and overall survival in allo-HSCT patients, further evaluation of microbiota injury and its associations with toxicities, PFS, and overall survival (OS) in AHCT patients is warranted. Figure 1: A: The median Simpson reciprocal a-diversity index (S) of pre-transplant (days -10 to 0) samples of AHCT and allo-HSCT patients from two centers, as well as two cohorts of healthy volunteers, was plotted and a pairwise Wilcox test was performed, with p-values as indicated. B: (S) was plotted against time relative to allo-HSCT (on L) and AHCT (on R), for samples collected from day -10 to day +30. Larger values indicate greater diversity. C: Microbiota composition and changes in bacterial monodominance after transplant (days -14 to +28); the most common genus post-transplant is Streptococcus.

Author summary Helminths are large multicellular parasites that infect approximately every third person. Infections are controlled by a concerted action of innate and adaptive immune responses. Basophils and mast cells are innate effector cells with overlapping functions that have recently been...

The effects of caesarean section delivery on mother-to-neonate transmission of microbiota are unclear. Here the authors show that caesarean section delivery can affect the transmission of specific microbial strains and the immunomodulatory potential of the microbiota.