Evaluation of Community-Based, Mobile HIV-Care, Peer-Delivered Linkage Case Management in Manzini Region, Eswatini.

The success of antiretroviral therapy (ART) requires continuous engagement in care and optimal levels of adherence to achieve sustained HIV viral suppression. We evaluated HIV-care cascade costs and outcomes of a community-based, mobile HIV-care, peer-delivered linkage case-management program (CommLink) implemented in Manzini region, Eswatini. Abstraction teams visited referral facilities during July 2019-April 2020 to locate, match, and abstract the clinical data of CommLink clients diagnosed between March 2016 and March 2018. An ingredients-based costing approach was used to assess economic costs associated with CommLink. The estimated total CommLink costs were $2 million. Personnel costs were the dominant component, followed by travel, commodities and supplies, and training. Costs per client tested positive were $499. Costs per client initiated on ART within 7, 30, and 90 days of diagnosis were $2114, $1634, and $1480, respectively. Costs per client initiated and retained on ART 6, 12, and 18 months after diagnosis were $2343, $2378, and $2462, respectively. CommLink outcomes and costs can help inform community-based HIV testing, linkage, and retention programs in other settings to strengthen effectiveness and improve efficiency.

High Coverage of Antiretroviral Treatment With Annual Home-Based HIV Testing, Follow-up Linkage Services, and Implementation of Test and Start: Findings From the Chókwè Health Demographic Surveillance System, Mozambique, 2014-2019.

BACKGROUND: Early antiretroviral therapy (ART) is necessary for HIV epidemic control and depends on early diagnosis and successful linkage to care. Since 2014, annual household-based HIV testing and counseling and linkage services have been provided through the Chókwè Health and Demographic Surveillance System for residents testing HIV positive in this high HIV-burden district. METHODS: District-wide Test and Start [T&S, ART for all people living with HIV (PLHIV)] began in August 2016, supported by systematic interventions to improve linkage to care and treatment. Annual rounds (R) of random household surveys were conducted to assess trends in population prevalence of ART use and viral load suppression (<1000 viral RNA copies/mL). RESULTS: Between R1 (April 2014-April 2015) and R5 (April 2018-Mar 2019), 46,090 (67.2%) of 68,620 residents aged 15-59 years were tested for HIV at home at least once, and 3711 were newly diagnosed with HIV and provided linkage services. Population prevalence of current ART use among PLHIV increased from 65.0% to 87.5% between R1 and R5. ART population prevalence was lowest among men aged 25-34 years (67.8%) and women aged 15-24 (78.0%), and highest among women aged 35-44 years (93.6%) and 45-59 years (93.7%) in R5. Viral load suppression prevalence increased among all PLHIV aged 15-59 years from 52.0% in R1 to 78.3% in R5. DISCUSSION: Between 2014 and 2019, Chókwè Health and Demographic Surveillance System residents surpassed the UNAIDS targets of ≥81% of PLHIV on ART and ≥73% virally suppressed. This achievement supports the combination of efforts from household-based HIV testing and counseling, support for linkage to care and treatment, and continued investments in T&S implementation.

Regulation of human DAP10 gene expression in NK and T cells by Ap-1 transcription factors.

Human NKG2D/DAP10 is an activation receptor expressed by NK and subsets of T cells, whose ligands include MHC class I chain-related (MIC) protein A and protein B and UL16-binding proteins that are often up-regulated by stress or pathological conditions. DAP10 is required for NKG2D/DAP10 cell surface expression and signaling capacity. Little is known about the mechanisms that regulate DAP10 gene expression. We describe the existence of multiple transcriptional start sites upstream of DAP10 exon 1 and identify the location of the basic promoter upstream of these starting sites. The promoter is active in NK and CD8+ T cells, but not in CD4+ T cells. We demonstrate TCR-mediated up-regulation of DAP10 transcription and found that a 40 bp region within the DAP10 promoter, containing an Ap-1 binding site, is largely responsible for this increased transcription. Using pull-down and chromatin immunoprecipitation assays, we show that the DAP10 promoter interacts with Ap-1 transcription factors in primary CD8+ T and NK cells in vitro and in vivo. Overexpression of c-Jun or c-Fos in NK and T cells led to enhanced DAP10 promoter activity and DAP10 protein expression. Taken together, our data indicate that Ap-1 is an important transcription factor for regulating DAP10 gene expression in human NK and T cells, and that Ap-1 plays a key role in the transactivation of DAP10 promoter following TCR stimulation.

IL-21 down-regulates NKG2D/DAP10 expression on human NK and CD8+ T cells.

IL-21 is a recently described cytokine, produced by activated Th cells, that shares significant homology with members of the IL-2 family of cytokines. IL-21 mediates its biological effects via the IL-21R in conjunction with the common receptor gamma-chain that is also shared by members of the IL-2 family. We report that culture of human primary NK and CD8+ T cells with IL-21 in combination with IL-2 results in significant reduction of the cell surface expression of NKG2D, compared with that in cells treated with IL-2 alone. The reduced expression of NKG2D after IL-21 culture had functional consequences for NK cell function, as assessed by NKG2D-mediated redirected lysis assays and degranulation assays, compared with NK cells treated with IL-2 alone. IL-21-mediated NKG2D down-regulation in human NK cells correlated with a marked reduction of DNAX-activating protein of 10 kDa (DAP10) transcription in cells treated with IL-2 in combination with IL-21 compared with cells stimulated with only IL-2. This was attributed to a dramatic reduction in DAP10 promoter activity, as assessed by a DAP10 luciferase reporter construct. In contrast to NKG2D expression, IL-21 was able to induce the expression of the NK activation receptors NKp30 and 2B4 as well as the costimulatory receptor CD28 on CD8+ T cells. These data indicate that IL-21 is able to channel NK and CD8+ T cell function by altering the expression pattern of activation/costimulatory receptors.