Long-Term Persistence of Mitochondrial DNA Instability in HIV-Exposed Uninfected Children during and after Exposure to Antiretroviral Drugs and HIV.

HIV-exposed uninfected (HEU) children show impaired health outcomes during childhood. A high rate of mitochondrial DNA (mtDNA) instability was reported in the blood of HEU at birth. We aimed to explore the relationship between these health outcomes and mtDNA deletions over time in a case series of 24 HEU children. MtDNA instability was assessed by deep sequencing and analyzed by eKLIPse-v2 algorithm at three time points, namely birth, 1 year, and 6 years of age. Association between mtDNA deletion and health outcomes, including growth, clinical, and neurodevelopmental parameters, were explored using univariate statistical analyses and after stratification with relevant variables. HEU children were selected with an equal male:female ratio. An elevated number of mtDNA deletions and duplications events was observed at 7 days' post-partum. Median heteroplasmy increased at one year of life and then returned to baseline by six years of age. The mtDNA instability was acquired and was not transmitted by the mother. No risk factors were significantly associated with mtDNA instability. In this small case series, we did not detect any association between any health outcome at 6 years and mtDNA instability measures. A significant effect modification of the association between the duration of maternal prophylaxis and child growth was observed after stratification with heteroplasmy rate. Genomic instability persists over time among HEU children but, despite its extension, stays subclinical at six years.

Mitochondrial DNA Instability Is Common in HIV-Exposed Uninfected Newborns.

Worldwide, one million HIV-exposed uninfected (HEU) children are born yearly, and chronic health impairments have been reported in these children. Mitochondrial DNA (mtDNA) instability and altered mtDNA content have been evidenced in these children, but an exhaustive characterization of altered mitochondrial genomes has never been reported. We applied deep mtDNA sequencing coupled to the deletion identification algorithm eKLIPse to the blood of HEU neonates (n = 32), which was compared with healthy controls (n = 15). Dried blood spots (DBS) from African HEU children were collected seven days after birth between November 2009 and May 2012. DBS from French healthy controls were collected at birth (or <3 days of life) in 2012 and in 2019. In contrast to the absence of mtDNA instability observed at the nucleotide level, we identified significant amounts of heteroplasmic mtDNA deletions in 75% of HEU children and in none of controls. The heteroplasmy rate of the 62 mtDNA deletions identified varied from 0.01% to up to 50%, the highest rates being broadly compatible with bioenergetic defect and clinical expression. mtDNA integrity is commonly affected in HEU neonates. The nature of the deletions suggests a mechanism related to aging or tumor-associated mtDNA instability. This child population may be at risk of additional mtDNA genetic alterations considering that they will be exposed to other mitotoxic drugs including antiretroviral or anti-tuberculosis treatment.

Longitudinal Follow-Up of Blood Telomere Length in HIV-Exposed Uninfected Children Having Received One Year of Lopinavir/Ritonavir or Lamivudine as Prophylaxis.

Telomere shortening can be enhanced upon human immunodeficiency virus (HIV) infection and by antiretroviral (ARV) exposures. The aim of this study was to evaluate the acute and long-term effect on telomere shortening of two ARV prophylaxes, lopinavir/ritonavir (LPV/r) and lamivudine (3TC), administered to children who are HIV-exposed uninfected (CHEU) to prevent HIV acquisition through breastfeeding during the first year of life, and to investigate the relationship between telomere shortening and health outcomes at six years of age. We included 198 CHEU and measured telomere length at seven days of life, at week-50 and at six years (year-6) using quantitative polymerase chain reaction. At week-50, telomere shortening was observed among 44.3% of CHEU, irrespective of the prophylactic treatment. Furthermore, this telomere shortening was neither associated with poor growth indicators nor neuropsychological outcomes at year-6, except for motor abilities (MABC test n = 127, ß = -3.61, 95%CI: -7.08, -0.14; p = 0.04). Safety data on telomere shortening for infant HIV prophylaxis are scarce. Its association with reduced motor abilities deserves further attention among CHEU but also HIV-infected children receiving ARV treatment.

Health Outcomes at School Age among Children Who Are HIV-Exposed but Uninfected with Detected Mitochondrial DNA Depletion at One Year.

Infant antiretroviral (ARV) prophylaxis given to children who are human immunodeficiency virus (HIV)-exposed but uninfected (CHEU) to prevent HIV transmission through breastfeeding previously proved its efficacy in the fight against the pediatric epidemic. However, few studies have investigated the short- and long-term safety of prophylactic regimens. We previously reported a decrease of mitochondrial DNA (mtDNA) content among CHEU who received one year of lamivudine (3TC) or lopinavir-boosted ritonavir (LPV/r) as infant prophylaxis. We aimed to describe mtDNA content at six years of age among these CHEU, including those for whom we identified mtDNA depletion at week 50 (decrease superior or equal to 50% from baseline), and to compare the two prophylactic drugs. We also addressed the association between mtDNA depletion at week 50 with growth, clinical, and neuropsychological outcomes at year 6. Quantitative PCR was used to measure mtDNA content in whole blood of CHEU seven days after birth, at week 50, and at year 6. Among CHEU with identified mtDNA depletion at week 50 (n = 17), only one had a persistent mtDNA content decrease at year 6. No difference between prophylactic drugs was observed. mtDNA depletion was not associated with growth, clinical, or neuropsychological outcomes at year 6. This study brought reassuring data concerning the safety of infant 3TC or LPV/r prophylaxis.

Mitochondrial DNA Parameters in Blood of Infants Receiving Lopinavir/Ritonavir or Lamivudine Prophylaxis to Prevent Breastfeeding Transmission of HIV-1.

Children who are human immunodeficiency virus (HIV)-exposed but uninfected (CHEU) accumulate maternal HIV and antiretroviral exposures through pregnancy, postnatal prophylaxis, and breastfeeding. Here, we compared the dynamics of mitochondrial DNA (mtDNA) parameters in African breastfed CHEU receiving lopinavir/ritonavir (LPV/r) or lamivudine (3TC) pre-exposure prophylaxis during the first year of life. The number of mtDNA copies per cell (MCN) and the proportion of deleted mtDNA (MDD) were assessed at day 7 and at week 50 post-delivery (PrEP group). mtDNA depletion was defined as a 50% or more decrease from the initial value, and mtDNA deletions was the detection of mtDNA molecules with large DNA fragment loss. We also performed a sub-analysis with CHEU who did not receive a prophylactic treatment in South Africa (control group). From day seven to week 50, MCN decreased with a median of 41.7% (interquartile range, IQR: 12.1; 64.4) in the PrEP group. The proportion of children with mtDNA depletion was not significantly different between the two prophylactic regimens. Poisson regressions showed that LPV/r and 3TC were associated with mtDNA depletion (reference: control group; LPV/r: PR = 1.75 (CI95%: 1.15-2.68), p < 0.01; 3TC: PR = 1.54 (CI95%: 1.00-2.37), p = 0.05). Moreover, the proportion of children with MDD was unexpectedly high before randomisation in both groups. Long-term health impacts of these mitochondrial DNA parameters should be investigated further for both CHEU and HIV-infected children receiving LPV/r- or 3TC- based regimens.