2 research outputs found
HPV-specific antibodies in female genital tract secretions captured via first-void urine retain their neutralizing capacity
Human papillomavirus (HPV) vaccines, primarily relying on neutralizing antibodies, have proven highly effective. Recently, HPV-specific antibodies have been detected in the female genital tract secretions captured by first-void urine (FVU), offering a minimally invasive diagnostic approach. In this study, we investigated whether HPV16-specific antibodies present in FVU samples retain their neutralizing capacity by using pseudovirion-based neutralization assays. Paired FVU and serum samples (vaccinated n = 25, unvaccinated n = 25, aged 18–25) were analyzed using two orthogonal pseudovirion-based neutralization assays, one using fluorescence microscopy and the other using luminescence-based spectrophotometry. Results were compared with HPV16-specific IgG concentrations and correlations between neutralizing antibodies in FVU and serum were explored. The study demonstrated the presence of neutralizing antibodies in FVU using both pseudovirion-based neutralization assays, with the luminescence-based assay showing higher sensitivity for FVU samples, while the fluorescence microscopy-based assay exhibited better specificity for serum and overall higher reproducibility. High Spearman correlation values were calculated between HPV16-IgG and HPV16-neutralizing antibodies for both protocols (rs: 0.54–0.94, p s: 0.44–0.91, p < .01). This study demonstrates the continued neutralizing ability of antibodies captured with FVU, supporting the hypothesis that HPV vaccination may reduce autoinoculation and transmission risk to the sexual partner. Although further protocol optimizations are warranted, these findings provide a foundation for future research and larger cohort studies that could have implications for the optimal design, evaluation, and implementation of HPV vaccination programs.</p
Resource-Efficient Nitrogen Removal from Source-Separated Urine with Partial Nitritation/Anammox in a Membrane-Aerated Biofilm Reactor
Source separation and decentralized urine treatment can
cut costs
in centralized wastewater treatment by diverting 80% of the nitrogen
load in sewage. One promising approach for nitrogen removal from source-separated
urine is partial nitritation/anammox (PN/A), reducing the aeration
demand by 67% and organic dosage by 100% compared to nitrification/denitrification.
While previous studies with suspended biomass have encountered stability
issues during PN/A treatment of urine, a PN/A biofilm was hypothesized
to be more resilient. Its use for urine treatment has been pioneered
here for maximum rates and efficiencies in an energy-efficient membrane-aerated
biofilm reactor (MABR). Nitrogen removal rates of 1.0 g N L–1 d–1 and removal efficiencies of 80–95%
were achieved during a 335-day operational period at 28 °C on
stabilized (pH > 11.5), diluted urine (10%). A balance between
N2 and NO3– formation was
observed
while optimizing the supply of O2 through intermittent
aeration and was rate limiting for the conversion toward N2. A short-term operation on less- and undiluted urine yielded N removal
rates of 0.6–0.8 g N L–1 d–1 and removal efficiencies of 93% on 66% urine and 85% on undiluted
urine. Metataxonomic analysis and fluorescence in situ hybridization confirmed the presence in the biofilm of nitrifiers
(Nitrosomonas, Nitrospira) at the
membrane side and anammox bacteria (“Candidatus
Brocadia”) at the anoxic bulk side. The findings
suggest that a biofilm approach to PN/A treatment of urine overcomes
stability issues and that a PN/A-MABR has significant potential for
resource-efficient decentralized urine treatment. In human long-duration
deep-space missions, this gravity-independent technology could produce
N2 to compensate artificial atmosphere losses while facilitating
water recovery from urine