HESN

Intestinal microbiota facilitates food breakdown for energy metabolism and influences the immune response, maintaining mucosal homeostasis. Overall, HIV infection is associated with intestinal dysbiosis and immune activation, which has been related to seroconversion in HIV-exposed individuals. However, it is unclear whether microbiota dysbiosis is the cause or the effect of immune alterations and disease progression or if it could modulate the risk of acquiring the HIV infection. We characterize the intestinal microbiota and determine its association with immune regulation in HIV-exposed seronegative individuals (HESN), HIV-infected progressors (HIV+), and healthy control (HC) subjects...

CD46 is the main receptor for complement protein C3 and plays an important role in adaptive immune responses. CD46 genetic variants are associated with susceptibility to several infectious and autoimmune diseases. Additionally, CD46 function can be subverted by HIV-1 to evade attack by complement, a strategy shared by viruses of other families. We sought to determine the association between CD46 gene variants and HIV-1 acquired through intravenous drug use (IDU) and sexual routes ( n = 823). Study subjects were of European ancestry and were HIV-1 infected ( n = 438) or exposed but seronegative ( n = 387)...

The female genital tract (FGT) is an important site of human immunodeficiency virus (HIV) infection. Discerning the nature of HIV-specific local immune responses is crucial for identifying correlates of protection in HIV-exposed seronegative (HESN) individuals. The present study involved a comprehensive analysis of soluble immune mediators, secretory immunoglobulins (sIg), natural killer (NK) cells, CXCR5+ CD8+ T cells, T follicular helper (Tfh) cells, and T regulatory cells (Tregs) in the vaginal mucosa as well as the nature and composition of the cervicovaginal microbiome in HESN women...

INTRODUCTION: The novel coronavirus (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a single-chain ribonucleic acid (RNA) virus. As of March 25, 2021, the total number of positive cases and fatalities in the Kingdom of Saudi Arabia (KSA) had reached 386,300 and 6624, respectively, with a case fatality rate of 1.71%. The KSA was among the leading nations to heed the advice of WHO officials and put strict precautionary and preventive measures in place to curb the early spread of COVID-19 before it was declared a global pandemic...

BACKGROUND: This study presents the demographic, epidemiological, and clinical characteristics of Coronavirus Disease 2019 (COVID-19) in Saudi Arabia (KSA). It identifies the important predictors of the disease prognosis. METHODS: The study reviewed and analysed a sample of 307,010 confirmed symptomatic COVID-19 cases, between March and August 2020, available in the health electronic surveillance system (HESN) of the Ministry of Health of KSA. Descriptive and univariate analyses were conducted...

BACKGROUND: The established aim of the Saudi Health Electronic Surveillance Network (HESN) is to support the prevention and control of different health events, and to facilitate the delivery of other public health programs. This study aims to evaluate the perceptions of active HESN users regarding its general performance through five major components: practicability, design, data and communication, technical support, and general impression. METHODS: A cross-sectional study was conducted in 2016 using a sample of active HESN users...

BACKGROUND: The established aim of the Saudi Health Electronic Surveillance Network (HESN) is to support the prevention and control of different health events, and to facilitate the delivery of other public health programs. This study aims to evaluate the perceptions of active HESN users regarding its general performance through five major components: practicability, design, data and communication, technical support, and general impression. METHODS: A cross-sectional study was conducted in 2016 using a sample of active HESN users...

NKG2C is an activating NK cell receptor encoded by a gene having an unexpressed deletion variant. Cytomegalovirus (CMV) infection expands a population of NKG2C+ NK cells with adaptive-like properties. Previous reports found that carriage of the deleted NKG2C- variant was more frequent in people living with HIV (PLWH) than in HIV- controls unexposed to HIV. The frequency of NKG2C+ NK cells positively correlated with HIV viral load (VL) in some studies and negatively correlated with VL in others. Here, we investigated the link between NKG2C genotype and HIV susceptibility and VL set point in PLWH...

HIV-specific CD8+ T cells are known to play a key role in viral control during acute and chronic HIV infection. Although many studies have demonstrated the importance of HIV-specific CD8+ T cells in viral control, its correlation with protection against HIV infection remains incompletely understood. To better understand the nature of the immune response that contributes to the early control of HIV infection, we analyzed the phenotype, distribution and function of anti-viral CD8+ T cells in a cohort of HIV-exposed seronegative (HESN) women, and compared them with healthy controls and HIV-infected individuals...

BACKGROUND: Hypereosinophilia (HE), defined by blood eosinophils > 1.5 ? 109/L persisting over one month, is commonly found in clinical practice. OBJECTIVE: This study aimed to explore etiologies, clinical characteristics, and outcome of HE. METHODS: The HE patients from a single center in Thailand during 2014-2019 were retrospectively reviewed. RESULTS: Among 166 HE patients, 102 (61.5%) cases had reactive HE (HER) of which 52% was due to parasitic infestations...

Immunological correlates of natural resistance to HIV have been identified in HIV-exposed seronegative (HESN) individuals and include a low-inflammatory genital mucosal status. The cervicovaginal epithelium has not been studied for such correlates despite constituting an important barrier against sexual HIV transmission. To fill this gap in knowledge, we collected samples of blood, cervical mononuclear cells, cervicovaginal lavage, and ectocervical tissue from Kenyan HESN sex workers (n = 29) and controls (n = 33)...

Worldwide, most Human Immunodeficiency Virus (HIV) infections are acquired through heterosexual intercourse, and in sub-Saharan Africa, 59% of new HIV infections affect women. Vaccines and microbicides hold promise for preventing the acquisition of HIV. To this end, the study of HIV highly exposed seronegative (HESN) female commercial sex workers (CSWs), who constitute a model of natural immunity to HIV, provides an exceptional opportunity to determine important clues for the development of preventive strategies...

Background: The coronavirus disease 2019 (COVID-19), caused by the novel severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), is a global public health emergency. Age and sex are two important factors associated with risks and outcomes of various diseases. COVID-19 morbidity also seems to be affected by patient age and sex. It has been found that older age groups have more severe COVID-19 symptoms and higher fatality rates while children tend to have lower prevalence and milder symptoms than adults...

The antibody molecule comprises a variable domain conferring antigen specificity and affinity distinct from the heavy chain constant (CH) domains dictating effector functions. We here interrogate this paradigm by evaluating the unique influence of the CH1α domain on epitope specificity and functions using two mucosal gp41-specific Fab-IgAs (FabA) derived from HIV-1 highly-exposed but persistently seronegative individuals (HESN). These HESN develop selectively affinity-matured HIV-1-specific mucosal IgA that target the gp41 viral envelope and might provide protection although by unclear mechanisms...

Background: The rapid emergence of the novel coronavirus disease 2019 (COVID-19) has resulted in millions of infected patients and hundreds of thousands of deaths worldwide. Health care services delivery is being compromised due to the surge in the number of infected patients during this pandemic. Aims: This study aimed to assess the risk factors associated with poor prognosis among COVID-19 patients in Saudi Arabia. Methods: This was a multi-centre retrospective cohort study that included all laboratory-confirmed COVID-19 cases with definitive outcomes in Saudi Arabia during March 2020...

BACKGROUND: Global healthcare is challenged following the COVID-19 pandemic, since late 2019. Multiple approaches have been performed to relieve the pressure and support existing healthcare. The Saudi Arabian Ministry of Health (MOH) launched an initiative to support the National Healthcare System. Since the 5th of June 2020, 238 outpatient fever clinics were established nationwide. This study aimed to assess the safety outcome and reported adverse events from hydroxychloroquine use among suspected COVID-19 patients...

Highly exposed seronegative (HESN) individuals present a unique setting to study mechanisms of protection against HIV acquisition. As natural killer (NK) cell activation and function have been implicated as a correlate of protection in HESN individuals, we sought to better understand the features of NK cells that may confer protection. We used mass cytometry to phenotypically profile NK cells from a cohort of Beninese sex workers and healthy controls. We found that NK cells from HESN women had increased expression of NKG2A, NKp30 and LILRB1, as well as the Fc receptor CD16, and decreased expression of DNAM-1, CD94, Siglec-7, and NKp44...

Innate immunity is the first line of defense against invading pathogens and may mediate HIV-1 resistance in HIV-1-exposed seronegative (HESN) individuals. This study aims to identify components of innate immunity that confer natural HIV-1 resistance in Chinese HESN individuals. Specifically, we compared the expression levels of Toll-like receptors (TLRs) and associated pathway molecules in peripheral blood mononuclear cells (PBMCs), monocytes/macrophages, and plasma obtained from HESN and control individuals...

BACKGROUND: 25-hydroxylase (CH25H) is an Interferon stimulated gene (ISG), which catalyzes the synthesis of 25-Hydroxycholesterol (25HC). 25HC intervenes in metabolic and infectious processes as controls cholesterol homeostasis and influences viral entry into host cells.We verified whether natural resistance to HIV-1 infection in HIV-1-exposed seronegative (HESN) individuals is at least partially mediated by particularities in sterol biosynthesis. METHODS: Peripheral blood mononuclear cells (PBMCs) and monocyte-derived macrophages (MDMs) isolated from 15 sexually-exposed HESN and 15 healthy controls (HC) were in vitro HIV-1-infected and analyzed for: 1) percentage of IFNα-producing plasmacytoid Dendritic Cells (pDCs); 2) Cholesterol signaling and inflammatory response RNA expression; 3) resistance to HIV-1 infection...

In rare cases, individuals with a history of long-term injecting drug use remain seronegative and aviraemic, despite prolonged and likely repeated exposure to HCV through high risk behaviour. We describe anti-HCV-Envelope (E) antibody responses in a prospective cohort of carefully-defined highly-exposed but uninfected subjects (HESN) and comparison subjects who were also high risk and uninfected, but rapidly became HCV infected (Incident). Longitudinally-collected samples from HESN cases (n=22) were compared to Incident controls (n=22)...