Short Communication: Evidence That Microbial Translocation Occurs in HIV-Infected Children in the United Kingdom

Abstract

Microbial translocation (MT) from the gut is implicated in driving immune activation, increasing morbidity and mortality in HIV. We used bacterial 16S rDNA PCR, Sanger sequencing, and high-throughput sequencing to identify microbial DNA in the bloodstream of HIV-infected children in London, United Kingdom. Blood samples were collected from sequential children attending the HIV clinic at Great Ormond Street Hospital, London. DNA extraction, broad range 16S rDNA PCR, and standard Sanger sequencing were carried out. A subset of positive samples was analyzed by high-throughput sequencing (Roche 454 platform). Of 105 samples collected from sequential children, nine were positive using broad range 16S rDNA PCR (8.6%; 95% CI 4.4-16%). From three amplicons, 16S rDNA sequences were identified as Streptococcus, Propionibacterium acnes, and coagulase-negative Staphylococcus. Four positive samples were analyzed by high-throughput sequencing. In the three samples in which organisms were identified by Sanger sequencing, the same species were identified. Further species, in differing proportions, were identified in all four samples. The identified organisms included known gut orders Bifidobacteriaceae, Lactobacillaceae, Bacteroidales, and Clostridiales. In immunocompetent children of equivalent age, no bacterial DNA was detected in blood using this approach. This is the first study to our knowledge using molecular techniques to identify MT in children in the developed world. Our data indicate that 16S rDNA is detectable in 8.6% of HIV-infected children. Levels of DNA were low and from multiple bacterial species. Further studies are needed to ascertain the importance of MT in HIV-infected children.

Is impaired kidney function an independent predictor of the risk of myocardial infarction in HIV-infected individuals?

“…This has been observed in HIV-infected adults [10]. Our results support previous observations that HIV-infected children have gut-associated lymphoid tissue injury resulting in persistent microbial translocation and/or defects in LPS clearance mechanisms [11][12][13]15,16].…”

“…During the acute phase of infection, the main driver of immune activation appears to be high levels of virus with other factors such as microbial translocation more important in chronic infection [8]. Few studies have focused on immune activation and microbial translocation profiles of HIVinfected children [11][12][13].…”

Term and preterm labour are associated with distinct microbial community structures in placental membranes which are independent of mode of delivery

“…Collection and DNA extraction was carried out as previously described [2]. Extracted DNA was amplified twice in separate PCR reactions, pyrosequenced on a 454 FLX Titanium (Roche) and the subsequent sequences analysed as previously described [4]. Reads were filtered above a level to remove spurious Operational Taxonomic Units generated by PCR or sequencing error (had to be present above 1% relative abundance in at least one sample).…”

Can We Control the Progression of HIV by Monitor Markers of Microbial Translocation?

“…Brenchley et al [11] first reported increased circulating LPS in both HIV-infected humans and SIVinfected rhesus macaques during chronic infection. More recently, clinical investigations [42,43] have confirmed that microbial translocation is also a major source of immune activation and may contribute to the rapid disease progression in HIV infected children [44]. But, in another study, Wittkop et al illuminated that autoimmune response and microbial translocation were not associated with immune activation [45].…”