Impact of HIV infection and anti-retroviral therapy on the immune profile of and microbial translocation in HIV-infected children in Vietnam

CD4+ T-lymphocyte destruction, microbial translocation, and systemic immune activation are the main mechanisms of the pathogenesis of human immunodeficiency virus type 1 (HIV) infection. To investigate the impact of HIV infection and antiretroviral therapy (ART) on the immune profile of and microbial translocation in HIV-infected children, 60 HIV vertically infected children (31 without ART: HIV(+) and 29 with ART: ART(+)) and 20 HIV-uninfected children (HIV(–)) aged 2–12 years were recruited in Vietnam, and their blood samples were immunologically and bacteriologically analyzed. Among the HIV(+) children, the total CD4+-cell and their subset (type 1 helper T-cell (Th1)/Th2/Th17) counts were inversely correlated with age (all p < 0.05), whereas regulatory T-cell (Treg) counts and CD4/CD8 ratios had become lower, and the CD38+HLA (human leukocyte antigen)-DR+CD8+- (activated CD8+) cell percentage and plasma soluble CD14 (sCD14, a monocyte activation marker) levels had become higher than those of HIV(–) children by the age of 2 years; the CD4/CD8 ratio was inversely correlated with the plasma HIV RNA load and CD8+-cell activation status. Among the ART(+) children, the total CD4+-cell and Th2/Th17/Treg-subset counts and the CD4/CD8 ratio gradually increased, with estimated ART periods of normalization being 4.8–8.3 years, whereas Th1 counts and the CD8+-cell activation status normalized within 1 year of ART initiation. sCD14 levels remained high even after ART initiation. The detection frequency of bacterial 16S/23S ribosomal DNA/RNA in blood did not differ between HIV-infected and -uninfected children. Thus, in children, HIV infection caused a rapid decrease in Treg counts and the early activation of CD8+ cells and monocytes, and ART induced rapid Th1 recovery and early CD8+-cell activation normalization but had little effect on monocyte activation. The CD4/CD8 ratio could therefore be an additional marker for ART monitoring. © 2016 by the authors; licensee MDPI, Basel, Switzerland

Diversity of Intestinal Clostridium coccoides Group in the Japanese Population, as Demonstrated by Reverse Transcription-Quantitative PCR.

We used sensitive rRNA-targeted reverse transcription-quantitative PCR (RT-qPCR) to quantify the Clostridium coccoides group, which is a major anaerobic population in the human intestine. For this purpose, the C. coccoides group was classified into 3 subgroups and 19 species for expediency in accordance with the existing database, and specific primers were newly developed to evaluate them. Population levels of the C. coccoides group in human feces determined by RT-qPCR were equivalent to those determined by fluorescence in situ hybridization. RT-qPCR analysis of fecal samples from 96 volunteers (32 young children, 32 adults and 32 elderly) by using the 22 new primer sets together with the C. coccoides group-specific primer setm revealed that (i) total counts obtained as the sum of the 3 subgroups and 19 species were equivalent to the results obtained by using the C. coccoides group-specific primer set; (ii) total C. coccoides-group counts in the elderly were significantly lower than those in young children and adults; (iii) genus Blautia was the most common subgroup in the human intestinal C. coccoides-group populations at all age populations tested; (iv) the prevalences of Fusicatenibacter saccharivorans and genus Dorea were significantly higher in adults than in young children and the elderly; and (v) the prevalences of C. scindens and C. hylemonae, both of which produce secondary bile acid in the human intestine, were significantly higher in the elderly than in young children and adults. Hierarchical clustering and principal component analysis showed clear separation of the bacterial components between adult and elderly populations. Taken together, these data suggest that aging plays an important role in the diversity of C. coccoides-group populations in human intestinal microbiota; changes in this diversity likely influence the health of the host

Gut Dysbiosis in Patients with Anorexia Nervosa.

Anorexia nervosa (AN) is a psychological illness with devastating physical consequences; however, its pathophysiological mechanism remains unclear. Because numerous reports have indicated the importance of gut microbiota in the regulation of weight gain, it is reasonable to speculate that AN patients might have a microbial imbalance, i.e. dysbiosis, in their gut. In this study, we compared the fecal microbiota of female patients with AN (n = 25), including restrictive (ANR, n = 14) and binge-eating (ANBP, n = 11) subtypes, with those of age-matched healthy female controls (n = 21) using the Yakult Intestinal Flora-SCAN based on 16S or 23S rRNA-targeted RT-quantitative PCR technology. AN patients had significantly lower amounts of total bacteria and obligate anaerobes including those from the Clostridium coccoides group, Clostridium leptum subgroup, and Bacteroides fragilis group than the age-matched healthy women. Lower numbers of Streptococcus were also found in the AN group than in the control group. In the analysis based on AN subtypes, the counts of the Bacteroides fragilis group in the ANR and ANBP groups and the counts of the Clostridium coccoides group in the ANR group were significantly lower than those in the control group. The detection rate of the Lactobacillus plantarum subgroup was significantly lower in the AN group than in the control group. The AN group had significantly lower acetic and propionic acid concentrations in the feces than the control group. Moreover, the subtype analysis showed that the fecal concentrations of acetic acid were lower in the ANR group than in the control group. Principal component analysis confirmed a clear difference in the bacterial components between the AN patients and healthy women. Collectively, these results clearly indicate the existence of dysbiosis in the gut of AN patients

Impact of HIV Infection and Anti-Retroviral Therapy on the Immune Profile of and Microbial Translocation in HIV-Infected Children in Vietnam

CD4+ T-lymphocyte destruction, microbial translocation, and systemic immune activation are the main mechanisms of the pathogenesis of human immunodeficiency virus type 1 (HIV) infection. To investigate the impact of HIV infection and antiretroviral therapy (ART) on the immune profile of and microbial translocation in HIV-infected children, 60 HIV vertically infected children (31 without ART: HIV(+) and 29 with ART: ART(+)) and 20 HIV-uninfected children (HIV(−)) aged 2–12 years were recruited in Vietnam, and their blood samples were immunologically and bacteriologically analyzed. Among the HIV(+) children, the total CD4+-cell and their subset (type 1 helper T-cell (Th1)/Th2/Th17) counts were inversely correlated with age (all p &lt; 0.05), whereas regulatory T-cell (Treg) counts and CD4/CD8 ratios had become lower, and the CD38+HLA (human leukocyte antigen)-DR+CD8+- (activated CD8+) cell percentage and plasma soluble CD14 (sCD14, a monocyte activation marker) levels had become higher than those of HIV(−) children by the age of 2 years; the CD4/CD8 ratio was inversely correlated with the plasma HIV RNA load and CD8+-cell activation status. Among the ART(+) children, the total CD4+-cell and Th2/Th17/Treg-subset counts and the CD4/CD8 ratio gradually increased, with estimated ART periods of normalization being 4.8–8.3 years, whereas Th1 counts and the CD8+-cell activation status normalized within 1 year of ART initiation. sCD14 levels remained high even after ART initiation. The detection frequency of bacterial 16S/23S ribosomal DNA/RNA in blood did not differ between HIV-infected and -uninfected children. Thus, in children, HIV infection caused a rapid decrease in Treg counts and the early activation of CD8+ cells and monocytes, and ART induced rapid Th1 recovery and early CD8+-cell activation normalization but had little effect on monocyte activation. The CD4/CD8 ratio could therefore be an additional marker for ART monitoring