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11 result(s) for "Khadka, Pragya"
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HIV-1 diversity considerations in the application of the Intact Proviral DNA Assay (IPDA)
The Intact Proviral DNA Assay (IPDA) was developed to address the critical need for a scalable method for intact HIV-1 reservoir quantification. This droplet digital PCR-based assay simultaneously targets two HIV-1 regions to distinguish genomically intact proviruses against a large background of defective ones, and its application has yielded insights into HIV-1 persistence. Reports of assay failures however, attributed to HIV-1 polymorphism, have recently emerged. Here, we describe a diverse North American cohort of people with HIV-1 subtype B, where the IPDA yielded a failure rate of 28% due to viral polymorphism. We further demonstrate that within-host HIV-1 diversity can lead the IPDA to underestimate intact reservoir size, and provide examples of how this phenomenon could lead to erroneous interpretation of clinical trial data. While the IPDA represents a major methodological advance, HIV-1 diversity should be addressed before its widespread adoption as a principal readout in HIV-1 remission trials. The intact proviral DNA assay quantifies the genomically intact HIV reservoir, but assay failure due to HIV-1 polymorphism has been observed. Here, the authors report a 28% failure rate in a cohort of people with HIV-1, and note within-host HIV-1 diversity as a further challenge to IPDA accuracy.
SARS CoV-2 mRNA vaccination exposes latent HIV to Nef-specific CD8+ T-cells
Efforts to cure HIV have focused on reactivating latent proviruses to enable elimination by CD8 + cytotoxic T-cells. Clinical studies of latency reversing agents (LRA) in antiretroviral therapy (ART)-treated individuals have shown increases in HIV transcription, but without reductions in virologic measures, or evidence that HIV-specific CD8 + T-cells were productively engaged. Here, we show that the SARS-CoV-2 mRNA vaccine BNT162b2 activates the RIG-I/TLR – TNF – NFκb axis, resulting in transcription of HIV proviruses with minimal perturbations of T-cell activation and host transcription. T-cells specific for the early gene-product HIV-Nef uniquely increased in frequency and acquired effector function (granzyme-B) in ART-treated individuals following SARS-CoV-2 mRNA vaccination. These parameters of CD8 + T-cell induction correlated with significant decreases in cell-associated HIV mRNA, suggesting killing or suppression of cells transcribing HIV. Thus, we report the observation of an intervention-induced reduction in a measure of HIV persistence, accompanied by precise immune correlates, in ART-suppressed individuals. However, we did not observe significant depletions of intact proviruses, underscoring challenges to achieving (or measuring) HIV reservoir reductions. Overall, our results support prioritizing the measurement of granzyme-B-producing Nef-specific responses in latency reversal studies and add impetus to developing HIV-targeted mRNA therapeutic vaccines that leverage built-in LRA activity. Here, the authors show in a cohort of people with HIV, COVID mRNA vaccination is followed by a transient boost in a particular profile of HIV-specific T-cell responses and a corresponding decrease in residual HIV RNA – suggesting productive immune engagement with infected cells.
HIV-1 subtype A1, D, and recombinant proviral genome landscapes during long-term suppressive therapy
The primary obstacle to curing HIV-1 is a reservoir of CD4+ cells that contain stably integrated provirus. Previous studies characterizing the proviral landscape, which have been predominantly conducted in males in the United States and Europe living with HIV-1 subtype B, have revealed that most proviruses that persist during antiretroviral therapy (ART) are defective. In contrast, less is known about proviral landscapes in females with non-B subtypes, which represents the largest group of individuals living with HIV-1. Here, we analyze genomic DNA from resting CD4+ T-cells from 16 female and seven male Ugandans with HIV-1 receiving suppressive ART ( n  = 23). We perform near-full-length proviral sequencing at limiting dilution to examine the proviral genetic landscape, yielding 607 HIV-1 subtype A1, D, and recombinant proviral sequences (mean 26/person). We observe that intact genomes are relatively rare and clonal expansion occurs in both intact and defective genomes. Our modification of the primers and probes of the Intact Proviral DNA Assay (IPDA), developed for subtype B, rescues intact provirus detection in Ugandan samples for which the original IPDA fails. This work will facilitate research on HIV-1 persistence and cure strategies in Africa, where the burden of HIV-1 is heaviest. Most studies on HIV-1 proviruses that persist during antiretroviral therapy have focused on males with HIV-1 subtype B, even though the majority of people living with HIV globally have non-B subtypes. Here, the authors describe the proviral genetic landscape of HIV-1 subtypes A1 and D in Ugandan females and males using near-full-length proviral sequencing. The authors also describe a molecular assay for intact proviral quantification of these HIV-1 subtypes.
HIV-specific T cell responses reflect substantive in vivo interactions with antigen despite long-term therapy
Antiretroviral therapies (ARTs) abrogate HIV replication; however, infection persists as long-lived reservoirs of infected cells with integrated proviruses, which reseed replication if ART is interrupted. A central tenet of our current understanding of this persistence is that infected cells are shielded from immune recognition and elimination through a lack of antigen expression from proviruses. Efforts to cure HIV infection have therefore focused on reactivating latent proviruses to enable immune-mediated clearance, but these have yet to succeed in reducing viral reservoirs. Here, we revisited the question of whether HIV reservoirs are predominately immunologically silent from a new angle: by querying the dynamics of HIV-specific T cell responses over long-term ART for evidence of ongoing recognition of HIV-infected cells. In longitudinal assessments, we show that the rates of change in persisting HIV Nef-specific responses, but not responses to other HIV gene products, were associated with residual frequencies of infected cells. These Nef-specific responses were highly stable over time and disproportionately exhibited a cytotoxic, effector functional profile, indicative of recent in vivo recognition of HIV antigens. These results indicate substantial visibility of the HIV-infected cells to T cells on stable ART, presenting both opportunities and challenges for the development of therapeutic approaches to curing infection.
SARS CoV-2 mRNA vaccination exposes latent HIV to Nef-specific CD8+ T-cells
Efforts to cure HIV have focused on reactivating latent proviruses to enable elimination by CD8+ cytotoxic T-cells. Clinical studies of latency reversing agents (LRA) in individuals treated with antiretroviral therapy (ART) have shown increases in HIV transcription, but without reductions in virologic measures, or evidence that HIV-specific CD8+ T-cells were productively engaged. Here, we show that the SARS-CoV-2 mRNA vaccine BNT162b2 activates the RIG-I/TLR – TNF – NFκb axis, resulting in transcription of HIV proviruses with minimal perturbations of T-cell activation and host transcription. T-cells specific for the early gene-product HIV-Nef uniquely increased in frequency and acquired effector functon(granzyme-B) in ART-treated individuals following SARS-CoV-2 mRNA vaccination. These parameters of CD8+ T-cell induction correlated strongly with significant decreases in cell-associated HIV mRNA, suggesting killing or suppression of cells transcribing HIV. These results are, to our knowledge, the first observation of an intervention-induced reduction in a measure of HIV persistence, accompanied by precise immune correlates, in ART-suppressed individuals. However, we did not observe significant depletions of intact proviruses, underscoring challenges to achieving (or measuring) HIV reservoir reductions. Overall, our results support prioritizing the measurement of granzyme-B-producing Nef-specific responses in latency reversal studies and add impetus to developing HIV-targeted mRNA therapeutic vaccines that leverage built-in LRA activity.
HIV-specific T-cell responses reflect substantive in vivo interactions with infected cells despite long-term therapy
Antiretroviral therapies (ART) durably suppress HIV replication to undetectable levels – however, infection persists in the form of long-lived reservoirs of infected cells with integrated proviruses, that re-seed systemic replication if ART is interrupted. A central tenet of our current understanding of this persistence is that infected cells are shielded from immune recognition and elimination through a lack of antigen expression from proviruses. Efforts to cure HIV infection have therefore focused on reactivating latent proviruses to enable immune-mediated clearance, but these have yet to succeed in driving reductions in viral reservoirs. Here, we revisited the question of whether HIV reservoirs are predominately immunologically silent from a new angle, by querying the dynamics of HIV-specific T-cell responses over long-term ART for evidence of ongoing recognition of HIV-infected cells. We show that T-cell responses to autologous reservoir viruses persist over years, and that the maintenance of HIV-Nef-specific responses was uniquely associated with residual frequencies of infected cells. These responses disproportionately exhibited a cytotoxic, effector functional profile, indicative of recent in vivo recognition of HIV-infected cells. These results indicate substantial visibility of the HIV reservoir to T-cells on stable ART, presenting both opportunities and challenges for the development of therapeutic approaches to curing HIV infection.
HIV Diversity Considerations in the Application of the Intact Proviral DNA Assay (IPDA)
The Intact Proviral DNA Assay (IPDA) was developed to address the critical need for a precise and scalable method for intact HIV reservoir quantification1. This duplexed droplet digital PCR (ddPCR) assay simultaneously targets the HIV Packaging Signal (Ψ) and the Rev Responsive Element (RRE) within Envelope (env) to distinguish genomically intact proviruses against a large background of defective ones2. The IPDA requires less time, resources, and biological material than the gold standard for replication-competent HIV reservoir measurement, the Quantitative Viral Outgrowth Assay (QVOA)3, and is being adopted in research and clinical studies4-7. In our cohort of HIV-1 subtype B-infected individuals from North America however, the IPDA yielded a 28% failure rate due to HIV polymorphism. We further demonstrate that within-host HIV diversity can lead the IPDA to underestimate intact HIV reservoir size, which could negatively impact clinical trial results interpretation. While the IPDA represents an important methodological advance, HIV diversity should be addressed before its widespread adoption. Competing Interest Statement Dr. R. Brad Jones declares that he has received payment for his previous role on the scientific advisory board of AbbVie Inc. Dr. Lynsay MacLaren declares that she holds the unpaid position of Advanced Practice Practitioner on the HIVMA Board of Directions. Dr. Marrianne Harris received honoraria paid to her institution for services as a consultant, membership on scientific advisory board and/or speaking engagement from Gilead Sciences Canada, Inc., Merck Canada Inc. and ViiV Healthcare
Cross-cultural adaptation of motivational interviewing for use in rural Nepal
Background Motivational Interviewing (MI) has a robust evidence base in facilitating behavior change for several health conditions. MI focuses on the individual and assumes patient autonomy. Cross-cultural adaptation can face several challenges in settings where individualism and autonomy may not be as prominent. Sociocultural factors such as gender, class, caste hinder individual decision-making. Key informant perspectives are an essential aspect of cross-cultural adaptation of new interventions. Here, we share our experience of translating and adapting MI concepts to the local language and culture in rural Nepal, where families and communities play a central role in influencing a person’s behaviors. Methods We developed, translated, field-tested, and adapted a Nepali MI training module with key informants to generate insights on adapting MI for the first time in this cultural setting. Key informants were five Nepali nurses who supervise community health workers. We used structured observation notes to describe challenges and experiences in cross-cultural adaptation. We conducted this study as part of a larger study on using MI to improve adherence to HIV treatment. Results Participants viewed MI as an effective intervention with the potential to assist patients poorly engaged in care. Regarding patient autonomy, they initially shared examples of family members unsuccessfully dictating patient behavior change. These discussions led to consensus that every time the family members restrict patient's autonomy, the patient complies temporarily but then resumes their unhealthy behavior. In addition, participants highlighted that even when a patient is motivated to change (e.g., return for follow-up), their family members may not “allow” it. Discussion led to suggestions that health workers may need to conduct MI separately with patients and family members to understand everyone’s motivations and align those with the patient’s needs. Conclusions MI carries several cultural assumptions, particularly around individual freedom and autonomy. MI adaptation thus faces challenges in cultures where such assumptions may not hold. However, cross-cultural adaptation with key informant perspectives can lead to creative strategies that recognize both the patient’s autonomy and their role as a member of a complex social fabric to facilitate behavior change.
TeamHerald@CHIPSAL 2026: Hate Speech Detection and Sentiment Analysis of Nepali Memes using Transformer-based Architectures and Ensemble Learning
The analysis of internet memes in the Nepali language is complicated by frequent code-mixing and a lack of established baseline resources. While memes inherently combine visual and textual elements, this study focuses on a text-centric approach by extracting embedded text using an OCR layer and modeling it with Transformer-based architectures. We evaluate six distinct models and investigate the comparative effectiveness of Hard and Soft Voting ensemble strategies across two tasks: binary hate speech detection and three-class sentiment analysis. Experimental results show that a standalone decoder-only model achieved the highest performance for binary classification, whereas the Soft Voting ensemble performed best for the multi-class sentiment task, yielding a 15.8% relative improvement in Macro F1-score over the strongest standalone baseline. These findings suggest that ensemble strategies behave differently across binary and multi-class tasks, highlighting the importance of selecting aggregation methods suited to the classification objective.