RESUMEN
Vaccine efforts to combat HIV are challenged by the global diversity of viral strains and shielding of neutralization epitopes on the viral envelope glycoprotein trimer. Even so, the isolation of broadly neutralizing Abs from infected individuals suggests the potential for eliciting protective Abs through vaccination. This study reports a panel of 58 mAbs cloned from a rhesus macaque (Macaca mulatta) immunized with envelope glycoprotein immunogens curated from an HIV-1 clade C-infected volunteer. Twenty mAbs showed neutralizing activity, and the strongest neutralizer displayed 92% breadth with a median IC50 of 1.35 µg/ml against a 13-virus panel. Neutralizing mAbs predominantly targeted linear epitopes in the V3 region in the cradle orientation (V3C) with others targeting the V3 ladle orientation (V3L), the CD4 binding site (CD4bs), C1, C4, or gp41. Nonneutralizing mAbs bound C1, C5, or undetermined conformational epitopes. Neutralization potency strongly correlated with the magnitude of binding to infected primary macaque splenocytes and to the level of Ab-dependent cellular cytotoxicity, but did not predict the degree of Ab-dependent cellular phagocytosis. Using an individualized germline gene database, mAbs were traced to 23 of 72 functional IgHV alleles. Neutralizing V3C Abs displayed minimal nucleotide somatic hypermutation in the H chain V region (3.77%), indicating that relatively little affinity maturation was needed to achieve in-clade neutralization breadth. Overall, this study underscores the polyfunctional nature of vaccine-elicited tier 2-neutralizing V3 Abs and demonstrates partial reproduction of the human donor's humoral immune response through nonhuman primate vaccination.
Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , Productos del Gen env del Virus de la Inmunodeficiencia Humana/inmunología , Vacunas contra el SIDA/inmunología , Animales , Anticuerpos Monoclonales/inmunología , Sitios de Unión/inmunología , Línea Celular , Epítopos/inmunología , Infecciones por VIH/inmunología , Humanos , Inmunización/métodos , Región Variable de Inmunoglobulina/inmunología , Macaca mulatta/inmunología , Células THP-1/inmunología , Vacunación/métodos , Proteínas del Envoltorio Viral/inmunologíaRESUMEN
Hearing loss is a debilitating disease that affects 10% of adults worldwide. Most sensorineural hearing loss is caused by the loss of mechanosensitive hair cells in the cochlea, often due to aging, noise, and ototoxic drugs. The identification of genes that can be targeted to slow aging and reduce the vulnerability of hair cells to insults is critical for the prevention of sensorineural hearing loss. Our previous cell-specific transcriptome analysis of adult cochlear hair cells and supporting cells showed that Clu, encoding a secreted chaperone that is involved in several basic biological events, such as cell death, tumor progression, and neurodegenerative disorders, is expressed in hair cells and supporting cells. We generated Clu-null mice (C57BL/6) to investigate its role in the organ of Corti, the sensory epithelium responsible for hearing in the mammalian cochlea. We showed that the deletion of Clu did not affect the development of hair cells and supporting cells; hair cells and supporting cells appeared normal at 1 month of age. Auditory function tests showed that Clu-null mice had hearing thresholds comparable to those of wild-type littermates before 3 months of age. Interestingly, Clu-null mice displayed less hair cell and hearing loss compared to their wildtype littermates after 3 months. Furthermore, the deletion of Clu is protected against aminoglycoside-induced hair cell loss in both in vivo and in vitro models. Our findings suggested that the inhibition of Clu expression could represent a potential therapeutic strategy for the alleviation of age-related and ototoxic drug-induced hearing loss.
Asunto(s)
Clusterina/deficiencia , Células Ciliadas Auditivas/fisiología , Pérdida Auditiva Sensorineural/prevención & control , Presbiacusia/prevención & control , Animales , Umbral Auditivo , Secuencia de Bases , Sistemas CRISPR-Cas , Senescencia Celular , Clusterina/biosíntesis , Clusterina/genética , Clusterina/fisiología , Sinergismo Farmacológico , Potenciales Evocados Auditivos del Tronco Encefálico , Furosemida/administración & dosificación , Furosemida/toxicidad , Células Ciliadas Auditivas/efectos de los fármacos , Pérdida Auditiva Sensorineural/inducido químicamente , Kanamicina/administración & dosificación , Kanamicina/toxicidad , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Técnicas de Cultivo de Órganos , Órgano Espiral/patología , Emisiones Otoacústicas Espontáneas , ARN Mensajero/biosíntesis , ARN Mensajero/genéticaRESUMEN
Age-related hearing loss (ARHL) negatively impacts quality of life in the elderly population. The prevalent cause of ARHL is loss of mechanosensitive cochlear hair cells (HCs). The molecular and cellular mechanisms of HC degeneration remain poorly understood. Using RNA-seq transcriptomic analyses of inner and outer HCs isolated from young and aged mice, we show that HC aging is associated with changes in key molecular processes, including transcription, DNA damage, autophagy, and oxidative stress, as well as genes related to HC specialization. At the cellular level, HC aging is characterized by loss of stereocilia, shrinkage of HC soma, and reduction in outer HC mechanical properties, suggesting that functional decline in mechanotransduction and cochlear amplification precedes HC loss and contributes to ARHL. Our study reveals molecular and cytological profiles of aging HCs and identifies genes such as Sod1, Sirt6, Jund, and Cbx3 as biomarkers and potential therapeutic targets for ameliorating ARHL.
Asunto(s)
Envejecimiento , Células Ciliadas Auditivas Externas , Anciano , Envejecimiento/fisiología , Animales , Proteínas Cromosómicas no Histona , Cóclea , Humanos , Mecanotransducción Celular , Ratones , Calidad de VidaRESUMEN
Increasingly, antibodies are being used to treat and prevent viral infections. In the context of HIV, efficacy is primarily attributed to dose-dependent neutralization potency and to a lesser extent Fc-mediated effector functions. It remains unclear whether augmenting effector functions of broadly neutralizing antibodies (bNAbs) may improve their clinical potential. Here, we use bNAb 10E8v4 targeting the membrane external proximal region (MPER) to examine the role of antibody-mediated effector and complement (C') activity when administered prophylactically against SHIV challenge in rhesus macaques. With sub-protective dosing, we find a 78-88% reduction in post-acute viremia that is associated with 10E8v4-mediated phagocytosis acting at the time of challenge. Neither plasma nor tissue viremic outcomes in vivo is improved with an Fc-modified variant of 10E8v4 enhanced for C' functions as determined in vitro. These results suggest that effector functions inherent to unmodified 10E8v4 contribute to efficacy against SHIVSF162P3 in the absence of plasma neutralizing titers, while C' functions are dispensable in this setting, informing design of bNAb modifications for improving protective efficacy.
Asunto(s)
Anticuerpos ampliamente neutralizantes/inmunología , Proteínas del Sistema Complemento/inmunología , Anticuerpos Anti-VIH/inmunología , VIH-1/inmunología , Fagocitosis/inmunología , Viremia/inmunología , Animales , Citotoxicidad Celular Dependiente de Anticuerpos/efectos de los fármacos , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Anticuerpos ampliamente neutralizantes/metabolismo , Anticuerpos ampliamente neutralizantes/farmacología , Línea Celular Tumoral , Proteínas del Sistema Complemento/metabolismo , Citocinas/inmunología , Citocinas/metabolismo , Femenino , Anticuerpos Anti-VIH/metabolismo , Anticuerpos Anti-VIH/farmacología , Infecciones por VIH/inmunología , Infecciones por VIH/prevención & control , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/fisiología , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/metabolismo , Macaca mulatta , Masculino , Fagocitosis/efectos de los fármacos , Síndrome de Inmunodeficiencia Adquirida del Simio/inmunología , Síndrome de Inmunodeficiencia Adquirida del Simio/prevención & control , Síndrome de Inmunodeficiencia Adquirida del Simio/virología , Virus de la Inmunodeficiencia de los Simios/efectos de los fármacos , Virus de la Inmunodeficiencia de los Simios/inmunología , Virus de la Inmunodeficiencia de los Simios/fisiología , Viremia/sangre , Viremia/prevención & controlRESUMEN
Vertical transmission accounts for most human immunodeficiency virus (HIV) infection in children, and treatments for newborns are needed to abrogate infection or limit disease progression. We showed previously that short-term broadly neutralizing antibody (bNAb) therapy given 24 h after oral exposure cleared simian-human immunodeficiency virus (SHIV) in a macaque model of perinatal infection. Here, we report that all infants given either a single dose of bNAbs at 30 h, or a 21-day triple-drug ART regimen at 48 h, are aviremic with almost no virus in tissues. In contrast, bNAb treatment beginning at 48 h leads to tight control without adaptive immune responses in half of animals. We conclude that both bNAbs and ART mediate effective post-exposure prophylaxis in infant macaques within 30-48 h of oral SHIV exposure. Our findings suggest that optimizing the treatment regimen may extend the window of opportunity for preventing perinatal HIV infection when treatment is delayed.