Early infancy as a window of time to modify the gut microbiota to support effective vaccine responses.

<p>Defining a critical time window for the manipulation of gut microbiota to support effective immune and vaccine responses may involve further investigation of (A) the infant humoral immune response development kinetics and (B) the characteristics of infant gut microbial colonization. (A) Curves represent various T and B cell response levels in newborn infants, with the upper bound being 100% of the adult levels. Kinetics of antibody responses were adapted from <i>Janeway’s Immunobiology</i> [<a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1005997#ppat.1005997.ref028" target="_blank">28</a>], Martin et al. [<a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1005997#ppat.1005997.ref027" target="_blank">27</a>], and Simon et al. [<a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1005997#ppat.1005997.ref026" target="_blank">26</a>]. The most abundant bacterial families of an infant gut microbiota at certain time points are shown with the size of the boxes representing their relative proportions. The relative abundance of bacterial families was based on studies by Arrieta et al. [<a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1005997#ppat.1005997.ref036" target="_blank">36</a>] and Collado et al. [<a href="http://www.plospathogens.org/article/info:doi/10.1371/journal.ppat.1005997#ppat.1005997.ref018" target="_blank">18</a>]. Abbreviations: T-I Ab response, T-independent antibody response.</p

Neoadjuvant Radiation Therapy and Surgery Improves Metastasis-Free Survival over Surgery Alone in a Primary Mouse Model of Soft Tissue Sarcoma.

This study aims to investigate whether adding neoadjuvant radiotherapy (RT), anti-programmed cell death protein-1 (PD-1) antibody (anti-PD-1), or RT + anti-PD-1 to surgical resection improves disease-free survival for mice with soft tissue sarcomas (STS). We generated a high mutational load primary mouse model of STS by intramuscular injection of adenovirus expressing Cas9 and guide RNA targeting Trp53 and intramuscular injection of 3-methylcholanthrene (MCA) into the gastrocnemius muscle of wild-type mice (p53/MCA model). We randomized tumor-bearing mice to receive isotype control or anti-PD-1 antibody with or without radiotherapy (20 Gy), followed by hind limb amputation. We used micro-CT to detect lung metastases with high spatial resolution, which was confirmed by histology. We investigated whether sarcoma metastasis was regulated by immunosurveillance by lymphocytes or tumor cell-intrinsic mechanisms. Compared with surgery with isotype control antibody, the combination of anti-PD-1, radiotherapy, and surgery improved local recurrence-free survival (P = 0.035) and disease-free survival (P = 0.005), but not metastasis-free survival. Mice treated with radiotherapy, but not anti-PD-1, showed significantly improved local recurrence-free survival and metastasis-free survival over surgery alone (P = 0.043 and P = 0.007, respectively). The overall metastasis rate was low (∼12%) in the p53/MCA sarcoma model, which limited the power to detect further improvement in metastasis-free survival with addition of anti-PD-1 therapy. Tail vein injections of sarcoma cells into immunocompetent mice suggested that impaired metastasis was due to inability of sarcoma cells to grow in the lungs rather than a consequence of immunosurveillance. In conclusion, neoadjuvant radiotherapy improves metastasis-free survival after surgery in a primary model of STS

In Children With Nonalcoholic Fatty Liver Disease, Cysteamine Bitartrate Delayed Release Improves Liver Enzymes but Does Not Reduce Disease Activity Scores

Background &amp; aimsNo treatment for nonalcoholic fatty liver disease (NAFLD) has been approved by regulatory agencies. We performed a randomized controlled trial to determine whether 52 weeks of cysteamine bitartrate delayed release (CBDR) reduces the severity of liver disease in children with NAFLD.MethodsWe performed a double-masked trial of 169 children with NAFLD activity scores of 4 or higher at 10&nbsp;centers. From June 2012 to January 2014, the patients were assigned randomly to receive CBDR or placebo twice daily (300 mg for patients weighing ≤65 kg, 375 mg for patients weighing &gt;65 to 80 kg, and 450 mg for patients weighing &gt;80 kg) for 52&nbsp;weeks. The primary outcome from the intention-to-treat analysis was improvement in liver histology over 52 weeks, defined as a decrease in the NAFLD activity score of 2 points or more without worsening fibrosis; patients without biopsy specimens from week 52 (17 in the CBDR group and 6 in the placebo group) were considered nonresponders. We calculated the relative risks (RR) of improvement using a stratified Cochran-Mantel-Haenszel analysis.ResultsThere was no significant difference between groups in the primary outcome (28% of children in the CBDR group vs 22% in the placebo group; RR, 1.3; 95% confidence interval [CI], 0.8-2.1; P&nbsp;= .34). However, children receiving CBDR had significant changes in&nbsp;prespecified secondary outcomes: reduced mean levels of&nbsp;alanine aminotransferase (reduction, 53 ± 88 U/L vs 8 ± 77 U/L in the placebo group; P&nbsp;= .02) and aspartate aminotransferase (reduction, 31 ± 52 vs 4 ± 36 U/L in the placebo group; P&nbsp;= .008), and a larger proportion had reduced lobular inflammation (36% in the CBDR group vs 21% in the placebo group; RR, 1.8; 95% CI, 1.1-2.9; P&nbsp;= .03). In a post hoc analysis of children weighing 65 kg or less, those taking CBDR had a 4-fold better chance of histologic improvement (observed in 50% of children in the CBDR group vs 13% in the placebo group; RR, 4.0; 95% CI, 1.3-12.3; P&nbsp;= .005).ConclusionsIn a randomized trial, we found that 1 year of CBDR did not reduce overall histologic markers of NAFLD compared with placebo in children. Children receiving CBDR, however, had significant reductions in serum aminotransferase levels and lobular inflammation. ClinicalTrials.gov no: NCT01529268