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Summary: Background: Surveillance data in high-income countries have reported more frequent SARS-CoV-2 diagnoses in ethnic minority groups. We examined the cumulative incidence of SARS-CoV-2 and its determinants in six ethnic groups in Amsterdam, the Netherlands. Methods: We analysed participants enrolled in the population-based HELIUS cohort, who were tested for SARS-CoV-2-specific antibodies and answered COVID-19-related questions between June 24-October 9, 2020 (after the first wave) and November 23, 2020-March 31, 2021 (during the second wave). We modelled SARS-CoV-2 incidence from January 1, 2020-March 31, 2021 using Markov models adjusted for age and sex. We compared incidence between ethnic groups over time and identified determinants of incident infection within ethnic groups. Findings: 2,497 participants were tested after the first wave; 2,083 (83·4%) were tested during the second wave. Median age at first visit was 54 years (interquartile range=44–61); 56·6% were female. Compared to Dutch-origin participants (15·9%), cumulative SARS-CoV-2 incidence was higher in participants of South-Asian Surinamese (25·0%; adjusted hazard ratio [aHR]=1·66; 95%CI=1·16–2·40), African Surinamese (28·9%, aHR=1·97; 95%CI=1·37–2·83), Turkish (37·0%; aHR=2·67; 95%CI=1·89–3·78), Moroccan (41·9%; aHR=3·13; 95%CI=2·22–4·42), and Ghanaian (64·6%; aHR=6·00; 95%CI=4·33–8·30) origin. Compared to those of Dutch origin, differences in incidence became wider during the second versus first wave for all ethnic minority groups (all p-values for interaction

Background: The latent HIV-1 reservoir in treated patients primarily consists of resting memory CD4+ T cells. Stimulating the T-cell receptor (TCR), which facilitates transition of resting into effector T cells, is the most effective strategy to purge these latently infected cells. Here we supply evidence that TCR-stimulated effector T cells still frequently harbor latent HIV-1. Methods: Primary HIV-1 infected cells were used in a latency assay with or without dendritic cells (DCs) and reversion of HIV-1 latency was determined, in the presence or absence of specific pathway inhibitors. Findings: Renewed TCR-stimulation or subsequent activation with latency reversing agents (LRAs) did not overcome latency. However, interaction of infected effector cells with DCs triggered further activation of latent HIV-1. When compared to TCR-stimulation only, CD4+ T cells from aviremic patients receiving TCR + DC-stimulation reversed latency more frequently. Such a “one-two punch” strategy seems ideal for purging the reservoir. We determined that DC contact activates the PI3K-Akt-mTOR pathway in CD4+ T cells. Interpretation: This insight could facilitate the development of a novel class of potent LRAs that purge latent HIV beyond levels reached by T-cell activation. Keywords: Dendritic cells, Latency, PI3K, Akt, mTOR, Activated T cells

Summary: The HIV latent reservoir forms the major hurdle to an HIV cure. The discovery of CD32 as marker of this reservoir has aroused much interest, but subsequent reports have challenged this finding. Here, we observe a positive correlation between the percentages of CD32+ cells among CD4+ T cells of aviremic cART-treated, HIV-infected individuals and their HIV DNA loads in peripheral blood. Moreover, optimization of the CD32+CD4+ T cell purification protocol reveals prominent enrichment for HIV DNA (mean, 292-fold) in these cells. However, no enrichment for HIV RNA is observed in CD32+CD4+ cells, yielding significantly reduced HIV RNA/DNA ratios. Furthermore, HIV proviruses in CD32+CD4+ cells can be reactivated ex vivo to produce virus, strongly suggesting that these cells support HIV transcriptional latency. Our results underscore the importance of isolating pure, bona fide CD32+CD4+ T cells for future studies and indicate that CD32 remains a promising candidate marker of the HIV reservoir. : CD32a was recently proposed to mark the HIV reservoir, but this finding was subsequently challenged. By using a sequential cell-sorting protocol to purify bona fide CD32+CD4+ cells, Darcis et al. demonstrate HIV DNA enrichment and ex vivo reactivation-mediated virus production in these cells, reinforcing CD32 as an HIV reservoir marker. Keywords: HIV reservoir, HIV latency, HIV cure, biomarker, HIV persistence, antiretroviral therapy, CD32