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McGuire, E.

Publications and source records attributed to McGuire, E..

3 recordsLinked to original sources

Lower Airway Dysbiosis in NTM+ Bronchiectasis is Associated with NET-Predominant Severe Phenotypes

RationaleThe discoveries of neutrophilic inflammation and Pseudomonas-dominant pulmonary dysbiosis have helped pave the way for host-directed therapy in bronchiectasis. Substantial knowledge gaps remain about the interplay between neutrophilic signatures and microbes in non-tuberculous mycobacterial lung disease (NTM-LD), a phenotypically diverse lung infection that is increasingly prevalent in the United States and other parts of the world. ObjectivesEvaluate the lower airway microbiota and neutrophilic traits in NTM- and NTM+ bronchiectasis. Methods16S rRNA gene sequencing, cell counts and neutrophil extracellular trap (NET) immunoassays were performed on bronchoscopic lower airway samples in 200 bronchiectasis subjects (108 NTM-, 92 NTM+). A preclinical model of oral commensal micro-aspiration and NTM infection was used to profile the murine lower airways with flow cytometry and a NET assay. Measurements and Main ResultsLower airways of NTM+ bronchiectasis patients were enriched with Mycobacterium and oral commensals (e.g., Veillonella, Prevotella). NET levels were higher in NTM+ BAL. Mycobacterium and oral commensals co-occurred with NET and neutrophils in network studies. Distinct oral commensal taxa associated with severe disease phenotypes such as cavitary disease and exacerbators. In a murine micro-aspiration model, the combination of oral commensals and Mycobacterium led to a sustained pro-inflammatory immune response marked by an increase in Th17, {gamma}8T cells, PD-1+ T lymphocytes as well as higher NET levels. ConclusionsOur analyses showed that distinct microbiome features beyond the primary pathogen can contribute to neutrophilic inflammation and severe disease phenotypes in bronchiectasis/ NTM-LD.

immunology↗

Maternal alum-adjuvanted recombinant HIV Env vaccine does not enhance autologous virus neutralization in HIV-infected pregnant women

Preventive strategies beyond ART will be required to end the pediatric HIV epidemic. A maternal vaccine capable of boosting neutralizing antibody (nAb) responses against circulating viruses in HIV-infected pregnant women could effectively decrease mother-to-child transmission of HIV. However, it is not known if an HIV envelope (Env) vaccine administered to infected pregnant women can enhance autologous virus neutralization. Here, we assessed autologous virus nAb responses in maternal plasma samples obtained from AIDS Vaccine Evaluation Group (AVEG) Protocols 104 and 102, historical Phase I safety and immunogenicity trials of recombinant HIV Env subunit vaccines in HIV-infected pregnant women (NCT00001041). AVEG 104 participants were randomized to receive 300 {micro}g Env subunit MN recombinant gp120 with alum adjuvant or alum alone. AVEG 102 participants were randomized to receive 640 {micro}g Env subunit recombinant gp160 or placebo. HIV Env-specific maternal plasma binding and neutralizing responses were characterized before and after vaccination in 15 AVEG 104 (n=10 vaccinee, n=5 placebo) and 2 AVEG 102 (n=1 vaccinee, n=1 placebo) participants. Single genome amplification (SGA) was used to obtain HIV env gene sequences from autologous viruses for pseudovirus production in pre- and post-vaccination plasma of HIV-infected pregnant vaccinees (n=6 gp120, n=1 gp160) and placebo recipients (n=3). We detected an increase in MN gp120-specific IgG binding in the vaccinee group between the first immunization visit and the last visit at delivery (p=0.027, 2-sided Wilcoxon test). However, no difference was observed in the neutralization potency of maternal plasma collected at delivery against autologous viruses isolated from early or late pregnancy. Thus, maternal vaccination with gp120/160 did not boost maternal autologous virus nAb responses. Immunization strategies capable of more potent B cell stimulation will likely be required to effectively boost autologous virus nAb responses in pregnant women and synergize with ART to further reduce infant HIV infections. HighlightsO_LIPrior maternal HIV Env vaccine trial did not assess autologous virus neutralization C_LIO_LICirculating viruses isolated from mothers were tested against autologous plasma C_LIO_LIMaternal vaccination with HIV Env gp120/160 increased MN gp120-specific IgG binding C_LIO_LIMaternal HIV Env vaccine regimen did not boost autologous virus neutralization C_LIO_LIMore potent B cell stimulation will be required to elicit autologous nAb responses C_LI

immunology↗

Infant Transmitted/Founder HIV-1 Viruses from Peripartum Transmission are Neutralization Resistant to Paired Maternal Plasma

Despite extensive genetic diversity of HIV-1 in chronic infection, infant HIV-1 infection involves selective transmission of a single or few maternal virus variants. These transmitted/founder (T/F) variants are of particular interest, as a maternal or infant HIV vaccine should raise envelope (Env)-specific IgG responses capable of blocking this group of viruses. However, the maternal or infant factors that contribute to selection of infant T/F viruses are not well understood. In this study, we isolated HIV-1 env genes by single genome amplification from 16 mother-infant transmitting pairs from the U.S. pre-antiretroviral era Women Infant Transmission Study (WITS). Infant T/F and representative maternal non-transmitted Env variants from plasma were identified and used to generate pseudoviruses for paired maternal plasma neutralization sensitivity analysis. Eighteen out of 21 (85%) infant T/F Env pseudoviruses were neutralization resistant to paired maternal plasma. Yet, all infant T/F viruses were neutralization sensitive to a panel of HIV-1 broadly neutralizing antibodies and variably sensitive to heterologous plasma neutralizing antibodies. Moreover, infant T/F pseudoviruses were overall more neutralization resistant compared to maternal non-transmitted plasma variants (p=0.012). Altogether, our findings suggest that autologous neutralization of circulating viruses by maternal plasma antibodies select for neutralization-resistant viruses that initiate peripartum transmission, raising the spector that enhancement of this response at the end of pregnancy could further reduce infant HIV infection risk.\n\nAuthor SummaryMother to child transmission (MTCT) of HIV-1 can occur during pregnancy (in utero), at the time of delivery (peripartum) or by breastfeeding (postpartum). With the availability of anti-retroviral therapy (ART), rate of MTCT of HIV-1 have been significantly lowered. However, significant implementation challenges remains in resource-poor areas, making it difficult to eliminate pediatric HIV. An improved understanding of the viral population (escape variants from autologous neutralizing antibodies) that lead to infection of infants at time of transmission will help in designing immune interventions to reduce vertical HIV-1 transmission. Here, we selected 16 HIV-1-infected mother-infant pairs from WITS cohort (from pre anti-retroviral era), where infants became infected peripartum. HIV-1 env gene sequences were obtained by the single genome amplification method. The sensitivity of these infant Env pseudoviruses against paired maternal plasma and a panel of broadly neutralizing monoclonal antibodies (bNAbs) was analyzed. We demonstrated that the infant T/F viruses were more resistant against maternal plasma than non-transmitted maternal variants, but sensitive to most (bNAbs). Signature sequence analysis of infant T/F and non-transmitted maternal variants revealed the potential importance of V3 and MPER region for resistance against to paired maternal plasma. These findings provide insights for the design of maternal immunization strategies to enhance neutralizing antibodies that target V3 region of autologous virus populations, which could work synergistically with maternal ARVs to further reduce the rate of peripartum HIV-1 transmission.

molecular biology↗