Interleukin-15 Enhances Cytotoxicity, Receptor Expression, and Expansion of Neonatal Natural Killer Cells in Long-Term Culture

Newborn infants have a higher susceptibility to various pathogens due to developmental defects in their host defense system, including deficient natural killer (NK) cell function. In this study, the effects of interleukin-15 (IL-15) on neonatal NK cells was examined for up to 12 weeks in culture. The cytotoxicity of fresh neonatal mononuclear cells (MNC) as assayed by K562 cell killing is initially much less than that of adult MNC but increases more than eightfold after 2 weeks of culture with IL-15 to a level equivalent to that of adult cells. This high level of cytotoxicity was maintained for up to 12 weeks. In antibody-dependent cellular cytotoxicity (ADCC) assays using CEM cells coated with human immunodeficiency virus gp120 antigen, IL-15 greatly increased ADCC lysis by MNC from cord blood. IL-15 increased expression of the CD16(+) CD56(+) NK markers of cord MNC fivefold after 5 weeks of incubation. Cultures of neonatal MNC with IL-15 for up to 10 weeks resulted in a unique population of CD3(−) CD8(+) CD56(+) cells (more than 60%), which are not present in fresh cord MNC. These results show that IL-15 can stimulate neonatal NK cells and sustain their function for several weeks, which has implications for the clinical use of IL-15

Performance of the Applied Biosystems ViroSeq Human Immunodeficiency Virus Type 1 (HIV-1) Genotyping System for Sequence-Based Analysis of HIV-1 in Pediatric Plasma Samples

The ViroSeq HIV-1 Genotyping System is a commercially available, integrated sequence-based system for analysis of human immunodeficiency virus type 1 (HIV-1) drug resistance. We evaluated the performance of this system by analyzing HIV-1 in pediatric plasma samples. Plasma samples from children 4 months to 17 years of age were obtained from a clinical trial protocol (PACTG 377). Children in PACTG 377 were randomized to four treatment arms, including different combinations of antiretroviral drugs. HIV-1 genotyping was performed using samples collected prior to antiretroviral therapy (baseline) and at the time of virologic failure. Performance of the genotyping system was compared in three university laboratories. A total of 196 samples were analyzed, including 135 baseline and 61 failure samples. Plasma volumes ranged from 0.05 to 0.5 ml, and viral loads ranged from 1,084 to 3,484,991 copies/ml. PCR products suitable for sequencing were obtained for 192 of the 196 samples. Complete sequences for protease and reverse transcriptase were obtained for all of these 192 samples. For 180 samples, data were obtained from both DNA strands for the entire region analyzed. There was no evidence of sample cross-contamination based on phylogenetic analysis of HIV-1 sequences. Performance of the genotyping system was similar in three laboratories. This genotyping system performs well for analysis of HIV-1 in pediatric plasma samples, including those with low volume and low viral load. The availability of this system should facilitate studies of HIV-1 drug resistance

Characteristics of the Sample Adequacy Control (SAC) in the Cepheid Xpert® CT/NG Assay in Female Urine Specimens

Made available in DSpace on 2015-04-08T14:09:57Z (GMT). No. of bitstreams: 2 license.txt: 1914 bytes, checksum: 7d48279ffeed55da8dfe2f8e81f3b81f (MD5) mariza_morgadoetal_IOC_2014.pdf: 1843908 bytes, checksum: bfc9e7b4bbe85317564c2073d3a1d8a7 (MD5) Previous issue date: 2014University of California. Fielding School of Public Health. Department of Epidemiology. Los Angeles, USA.University of California. David Geffen UCLA School of Medicine. USA.University of California. David Geffen UCLA School of Medicine. USA.University of California. David Geffen UCLA School of Medicine. USA.Hospital Geral de Nova Iguaçu. Nova Iguaçu, RJ, Brazil.Hospital Federal dos Servidores do Estado. Rio de Janeiro, Brazil.University of California. David Geffen UCLA School of Medicine. USA.Fundação Oswaldo Cruz. Instituto de Pesquisa Clinica Evandro Chagas. Rio de Janeiro, RJ, Brasil.Fundação Oswaldo Cruz. Instituto Oswaldo Cruz. Rio de Janeiro, RJ, Brasil.National Institutes of Health. 4Eunice Kennedy Shriver National Institute of Child Health and Human Development. USA.Background: The Xpert® CT/NG (Cepheid Sunnyvale, CA) is a rapid, fully automated real-time polymerase chain reaction test that simultaneously detects Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG). It has high sensitivity and specificity, but also includes a Specimen Adequacy Control (SAC). SAC controls for false negative results by confirming adequate patient sample and appropriate testing conditions. SAC is quantified by its cycle threshold (Ct), the number of cycles required to detect the presence of a single copy human gene. A lower SAC indicates an earlier Ct and more human cellular material detected. Our objectives were to describe the frequency and distribution of SAC Ct values and observe any correlations with detected infections. Methods: Urine samples from 1382 HIV-1-infected pregnant women, collected at the time of labor/delivery underwent Xpert® CT/NG testing. Mean SAC Ct values and standard deviation (SD) were calculated. Student’s t-test was used to compare mean SAC Ct values to a reference of urine samples negative for CT and NG. Results: The urine CT positivity was 17.9% (248/1382) and NG, 4.6% (63/1382). The mean SAC Ct value in urine from women without CT or NG was 28.09 (SD: 4.12) and higher than the mean SAC Ct value for CT positive specimens (27.29, SD: 3.84(P=.0054)), NG positive specimens (26.23, SD: 3.09(P<.0001)), and specimens positive for both CT and NG (26.41, SD: 3.01(P=.0027)). Conclusion: Lower SAC Ct values were significantly associated with chlamydial and gonococcal infections. Further studies should be conducted to determine the utility of SAC Ct values for identifying the presence of increased human cellular material and infectio

Demographics of Youth With Newly Diagnosed Acute/Recent HIV Infection in Adolescent Trials Network 147: Early Treatment of Acute HIV Infection

PurposeGay, bisexual, and other cisgender men who have sex with men, and racial minority youth are at elevated risk of acquiring HIV infection. The Adolescent Trials Network 147 recruited youth with acute/recent HIV-infection for early antiretroviral treatment. The cohort make-up is described here.MethodsTreatment-naïve, recently identified HIV&nbsp;+ youth, aged 12-24&nbsp;years, from Los Angeles and New Orleans were recruited from community centers, clinics, social media, and a high-risk seronegative cohort (n&nbsp;= 1,727, the Adolescent Trials Network 149) using point-of-care assays. Acute HIV infection was determined by Fiebig staging. HIV RNA viral load (VL) and CD4 cell counts, along with demographic and behavioral data were assessed at enrollment.ResultsBetween July 2017 and July 2021, 103 newly diagnosed youth were enrolled, initiating antiretroviral treatment within a week. Mean age was 20.8&nbsp;years (standard deviation: 2.4); 90.3% identified as cis male, 83.5% were single or in casual relationships, 71.8% were gay, bisexual, and other cisgender men who have sex with men; 60.2% were Black. One-fourth (24.3%) reported homelessness ever; 10.7% within last 4&nbsp;months. At enrollment, median plasma VL was 37,313 HIV RNA copies/ml (interquartile range: 5,849-126,162) and median CD4 count 445.5&nbsp;cells/mm3 (interquartile range: 357-613). 40% of youth reported acute retroviral symptoms before or at enrollment. Acutely infected, seroconverting youth had the highest VL. Sexually transmitted coinfections were present at enrollment in 56% of the cohort, with syphilis being most frequent (39%).DiscussionEarly identification and treatment of HIV can increase positive HIV outcomes. A high sexually transmitted infection burden was present in recently HIV-infected youth. Acute retroviral symptoms were not reported by most participants, demonstrating that broad universal HIV screening is needed for identification of recent infection in youth

Congenital Cytomegalovirus and HIV Perinatal Transmission

BackgroundCongenital cytomegalovirus (CMV) infection (cCMV) is an important cause of hearing loss and cognitive impairment. Prior studies suggest that HIV-exposed children are at higher risk of acquiring cCMV. We assessed the presence, magnitude and risk factors associated with cCMV among infants born to HIV-infected women, who were not receiving antiretrovirals during pregnancy.MethodscCMV and urinary CMV load were determined in a cohort of infants born to HIV-infected women not receiving antiretrovirals during pregnancy. Neonatal urines obtained at birth were tested for CMV DNA by qualitative and reflex quantitative real-time polymerase chain reaction.ResultsUrine specimens were available for 992 (58.9%) of 1684 infants; 64 (6.5%) were CMV-positive. Mean CMV load (VL) was 470,276 copies/ml (range: &lt; 200-2,000,000 copies/ml). Among 89 HIV-infected infants, 16 (18%) had cCMV versus 42 (4.9%) of 858 HIV-exposed, uninfected infants (P &lt; 0.0001). cCMV was present in 23.2% of infants with in utero and 9.1% infants with intrapartum HIV infection (P &lt; 0.0001). Rates of cCMV among HIV-infected infants were 4-fold greater (adjusted OR, 4.4; 95% CI: 2.3-8.2) and 6-fold greater among HIV in utero-infected infants (adjusted OR, 6; 95% CI: 3-12.1) compared with HIV-exposed, uninfected infants. cCMV was not associated with mode of delivery, gestational age, Apgar scores, 6-month infant mortality, maternal age, race/ethnicity, HIV viral load or CD4 count. Primary cCMV risk factors included infant HIV-infection, particularly in utero infection.ConclusionHigh rates of cCMV with high urinary CMV VL were observed in HIV-exposed infants. In utero HIV infection appears to be a major risk factor for cCMV in infants whose mothers have not received combination antiretroviral therapy in pregnancy