pH-triggered polymeric nanoparticles in gel for preventing vaginal transmission of HIV and unintended pregnancy.

Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/ AIDS) and unplanned pregnancy affect female reproductive health globally. A single product providing a dual purpose of HIV prophylaxis and contraception may improve adherence to the therapy. Thus, we formulated a female-centric multipurpose prevention technology (MPT) comprising of nanoparticle loaded vaginal gel formulation acting as a contraceptive and microbicide. Eudragit® S100 nanoparticles of Atazanavir sulphate (ATZ; antiviral) and Fluoxetine hydrochloride (FLX; repurposed spermicide) were prepared for pH dependent drug release and loaded in carrageenan and HPMC K200M gel. The particle size of ATZ and FLX nanoparticles was 396.7 ± 20.64 nm and 226.5 ± 2.08 nm respectively. The in vitro release of the gel formulation in simulated seminal fluid (pH 7.6) showed 96.16% and 95.98% release of ATZ and FLX respectively at the end of 8 h. The in vitro anti-HIV and spermicidal activity of the formulation was above 80% for low drug concentrations. In vivo studies on murine model showed no signs of inflammation or vaginal epithelial injury. Curcumin based imaging confirmed the retention of the formulation in the reproductive tract of mice with minimal leakage. Nanoparticles in gel enabled non-invasive and localised delivery with minimal side effects and can be an effective prophylactic therapy.

Immune profile of primary and recurrent epithelial ovarian cancer cases indicates immune suppression, a major cause of progression and relapse of ovarian cancer.

BACKGROUND: Ovarian cancer is the third most prevalent cancer in Indian women. Relative frequency of High grade serous epithelial ovarian cancer (HGSOC) and its associated deaths are highest in India which suggests the importance of understanding their immune profiles for better treatment modality. Hence, the present study investigated the NK cell receptor expression, their cognate ligands, serum cytokines, and soluble ligands in primary and recurrent HGSOC patients. We have used multicolor flow cytometry for immunophenotyping of tumor infiltrated and circulatory lymphocytes. Procartaplex, and ELISA were used to measure soluble ligands and cytokines of HGSOC patients. RESULTS: Among the enrolled 51 EOC patients, 33 were primary high grade serous epithelial ovarian cancer (pEOC) and 18 were recurrent epithelial ovarian cancer (rEOC) patients. Blood samples from 46 age matched healthy controls (HC) were used for comparative analysis. Results revealed, frequency of circulatory CD56Bright NK, CD56Dim NK, NKT-like, and T cells was reduced with activating receptors while alterations in immune subsets with inhibitory receptors were observed in both groups. Study also highlights differential immune profile of primary and recurrent ovarian cancer patients. We have found increased soluble MICA which might have acted as "decoy" molecule and could be a reason of decrease in NKG2D positive subsets in both groups of patients. Furthermore, elevated level of serum cytokines IL-2, IL-5, IL-6, IL-10, and TNF-α in ovarian cancer patients, might be associated with ovarian cancer progression. Profiling of tumor infiltrated immune cells revealed the reduced level of DNAM-1 positive NK and T cells in both groups than their circulatory counterpart, which might have led to decrease in NK cell's ability of synapse formation. CONCLUSIONS: The study brings out differential receptor expression profile on CD56BrightNK, CD56DimNK, NKT-like, and T cells, cytokines levels and soluble ligands which may be exploited to develop alternate therapeutic approaches for HGSOC patients. Further, few differences in the circulatory immune profiles between pEOC and rEOC cases, indicates the immune signature of pEOC undergoes some changes in circulation that might facilitated the disease relapse. They also maintains some common immune signatures such as reduced expression of NKG2D, high level of MICA as well as IL-6, IL10 and TNF-α, which indicates irreversible immune suppression of ovarian cancer patients. It is also emphasized that a restoration of cytokines level, NKG2D and DNAM-1on tumor infiltrated immune cells may be targeted to develop specific therapeutic approaches for high-grade serous epithelial ovarian cancer.

The dynamics of SARS-CoV-2 infection in unvaccinated and vaccinated populations in Mumbai, India, between 28 December 2020 and 30 August 2021.

The emergence and evolution of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants that could compromise vaccine efficacy (VE) with re-infections in immunized individuals have necessitated continuous surveillance of VE. Here, the occurrence and dynamics of SARS-CoV-2 infections in the context of vaccination during the second wave of infection in Mumbai were evaluated. RT-PCR cycle threshold (Ct) values of the open reading frame (ORF)/envelope (E)/nucleocapsid (N) genes obtained from a total of 42415 samples, comprising unvaccinated (96.88%) and vaccinated cases (3.12%) were analyzed between December 28, 2020, and August 30, 2021. A lower incidence of SARS-CoV-2 infection in fully vaccinated cases (5.07%) compared to partially vaccinated cases (6.5%) and unvaccinated cases (13.453%) was recorded. VE was significant after the first dose of vaccination (ORF gene p-value = 0.003429, and E/N gene p-value = 0.000866). Furthermore, VE was observed to be significant when the post-immunization (first dose) period was stratified to within 30 days (ORF gene p-value = 0.0094 and E/N gene p-value = 0.0023) and to 60 days following the second dose of vaccination (ORF gene p-value = 0.0238). Also, significantly higher efficacy was observed within individuals receiving two doses compared to a single dose (ORF gene p-value = 0.0132 and E/N gene p-value = 0.0387). The emergence of breakthrough infections was also evident (odds ratio= 0.34; 95% confidence interval= 0.27-0.43). Interestingly, viral loads trended towards being higher in some groups of partially vaccinated individuals compared to completely vaccinated and unvaccinated populations. Finally, our results delineated a significantly higher incidence of SARS-CoV-2 acquisition in males, asymptomatic individuals, individuals with comorbidities, and those who were unvaccinated.

A novel gut microbiome-immune axis influencing pathology in HCMV infected infants with neonatal cholestasis.

The interplay of active HCMV infection with gut dysbiosis in the immunopathology of cholestasis in neonates and infants remains unexplored. In this study, we evaluated gut microbiome profiles and immune dysfunction in a cohort of HCMV infected cholestatic infants (IgM positive, N = 21; IgM negative, N = 25) compared to healthy infants, N = 10. HCMV infected IgM positive individuals exhibited increased clinical severity in terms of liver dysfunction, altered CD4+: CD8+ ratio, and elevated Granzyme B levels in cellular immune subsets. Gut microbiome analysis revealed distinct and differential diversity and composition within infected groups aligned with clinical severity reflected through the increased abundance of Gammaproteobacteria, reduced Bifidobacteria, and a unique signature mapping to the HCMV infected IgM negative group. Correlation analyses revealed associations between Bifidobacterium breve, Gammaproteobacteria, Firmicutes, Clostridia, Finegoldia magna, Veillonella dispar, and Granzyme B expressing immune cell subsets. Our study describes a novel gut microbiome-immune axis that may influence disease severity in cholestatic infants with active HCMV infection.

Integrated immune monitoring of HCMV infection in pregnant women with complications and its association with adverse pregnancy outcomes.

Human Cytomegalovirus (HCMV) infection is associated with bad obstetric history (BOH) and adverse pregnancy outcomes (APO). Here, we characterized antiviral humoral profiles, systemic and virus specific cellular immune responses concurrently in pregnant women (n = 67) with complications including BOH and associated these signatures with pregnancy outcomes. Infection status was determined using nested blood PCR, seropositivity and IgG avidity by ELISA. Systemic and HCMV specific (pp65) cellular immune responses were evaluated by flow cytometry. Seropositivity was determined for other TORCH pathogens (n = 33) on samples with recorded pregnancy outcomes. This approach was more sensitive in detecting HCMV infection. Blood PCR positive participants, irrespective of their IgG avidity status, had higher cytotoxic potential in circulating CD8+ T cells (p < 0.05) suggesting that infection associated cellular dysfunction was uncoupled with avidity maturation of antiviral humoral responses. Also, impaired anamnestic degranulation of HCMV-pp65-specific T cells compared to HCMV blood PCR negative participants (p < 0.05) was observed. APO correlated with HCMV blood PCR positivity but not serostatus (p = 0.0039). Most HCMV IgM positive participants (5/6) were HCMV blood PCR positive with APO. None were found to be IgM positive for other TORCH pathogens. Multiple TORCH seropositivity however was significantly enriched in the APO group (p = 0.024). Generation of HCMV specific high avidity IgG antibodies had no bearing on APO (p = 0.9999). Our study highlights the utility of an integrated screening approach for antenatal HCMV infection in the context of BOH, where infection is associated with systemic and virus specific cellular immune dysfunction as well as APO.

Cytomegalovirus reactivation in a SARS-CoV-2 infected woman experiencing fetal demise in the first trimester with fetal trisomy 21: A case report.

Cytomegalovirus (CMV) is the most common cause of congenital viral infections. Women seropositive for CMV prior to pregnancy can develop a non-primary CMV infection. Here, we present a case of first trimester pregnancy loss during active SARS-CoV-2 infection. There was no evidence of SARS-CoV-2 RNA in placenta and fetal tissue, but there was presence of congenital cytomegalovirus infection by nested PCR. To the best of our knowledge, this is the first report demonstrating association of early congenital CMV infection due to reactivation and fetal demise in a SARS-CoV-2 positive woman with fetal trisomy 21.

LHX2 in germ cells control tubular organization in the developing mouse testis.

In the gonads of mammalian XY embryos, the organization of cords is the hallmark of testis development. This organization is thought to be controlled by interactions of the Sertoli cells, endothelial and interstitial cells with little or no role of germ cells. Challenging this notion, herein we show that the germ cells play an active role in the organization of the testicular tubules. We observed that the LIM-homeobox gene, Lhx2 is expressed in the germ cells of the developing testis between E12.5-E15.5. In Lhx2 knockout-fetal testis there was altered expression of several genes not just in germ cells but also in the supporting (Sertoli) cells, endothelial cells, and interstitial cells. Further, loss of Lhx2 led to disrupted endothelial cell migration and expansion of interstitial cells in the XY gonads. The cords in the developing testis of Lhx2 knockout embryos are disorganized with a disrupted basement membrane. Together, our results show an important role of Lhx2 in testicular development and imply the involvement of germ cells in the tubular organization of the differentiating testis. The preprint version of this manuscript is available at https://doi.org/10.1101/2022.12.29.522214.

Characterization of peripheral T helper 17 (Th17) cells phenotype in postmenopausal women with estrogen insufficiency.

Over the past few years, Th17 cells is considered a key player in osteoporosis pathogenesis. Although extensively studied in murine models, comprehensive Th17 cell characterization in osteoporotic women is elusive. We thus aimed to examine peripheral Th17 cells frequency and phenotypes in healthy and osteoporotic women. Our results demonstrated that Th17 cells were primarily CD4+CD45RA-CCR7-HALDR+CCR6lowT-cells. Compared to Pre-N, Post-L showed increased proportion of Th17 with concomitant decrease in Th1 cells. The Th17 cells frequency in effector memory CD4+ T cells was significantly elevated in Post-N with a decrease of Th1 cells in effector memory subsets compared to Pre-N and Post-L. Both Post-N and Post-L had decreased frequency of dual positive Th1-Th17 cells and increased HLA-DR expression on Th17 cells compared to Pre-N. Thus, our study demonstrates increased Th17 cells frequency and reduced Th1 cells frequency with effector memory phenotype in postmenopausal women with estrogen insufficiency and correlates with aging process.

Highly dampened HIV-specific cytolytic effector T cell responses define viremic non-progression.

This study reports on HIV-specific T cell responses in HIV-1 infected Viremic Non-Progressors (VNPs), a rare group of people living with HIV that exhibit asymptomatic infection over several years accompanied by stable CD4+ T cell counts in spite of ongoing viral replication. We attempted to identify key virus-specific functional attributes that could underlie the apparently paradoxical virus-host equilibrium observed in VNPs. Our results revealed modulation of HIV-specific CD4+ and CD8+ effector T cell responses in VNPs towards a dominant non-cytolytic profile with concomitantly diminished degranulation (CD107a+) ability. Further, the HIV specific CD8+ effector T cell response was primarily enriched for MIP-1ß producing cells. As expected, concordant with better viral suppression, VCs exhibit a robust cytolytic T cell response. Interestingly, PuPs shared features common to both these responses but did not exhibit a CD4+ central memory IFN-γ producing Gag-specific response that was shared by both non-progressor (VC and VNP) groups, suggesting CD4 helper response is critical for non-progression. Our study also revealed that cytolytic response in VNPs is primarily limited to polyfunctional cells while both monofunctional and polyfunctional cells significantly contribute to cytolytic responses in VCs. To further understand mechanisms underlying the unique HIV-specific effector T cell response described here in VNPs we also evaluated and demonstrated a possible role for altered gut homing in these individuals. Our findings inform immunotherapeutic interventions to achieve functional cures in the context of ART resistance and serious non AIDS events.

Estrogen receptor expression is modulated in human and mouse prostate epithelial cells during cancer progression.

Substantial data posit estrogen receptors (ERs) as promising targets for prostate cancer (PCa) therapeutics. However, the trials on assessing the chemo-preventive or therapeutic potential of ER targeting drugs or selective estrogen receptor modulators (SERMs) have not yet established their clinical benefits. This could be ascribed to a possible modulation in the ER expression during PCa progression. Further it is warranted to test various ER targeting drugs in appropriate preclinical models that simulate human ER expression pattern during PCa progression. The study was undertaken to revisit the existing data on the epithelial ER expression pattern in human cancerous prostates and experimentally determine whether these patterns are replicated in TRAMP (Transgenic Adenocarcinoma of Mouse Prostate) mice, a model for human PCa. Estradiol (E2) binding to the plasma membrane of the epithelial cells and its modulation during the PCa progression in TRAMP were also investigated. A reassessment of the existing data revealed a trend towards downregulation in the epithelial expression of wild-type ESR1 transcripts in high-grade PCa, compared to non-cancerous prostate in humans. Next, epithelial cell-enriched populations from TRAMP prostates (TP) displaying low-grade prostatic intraepithelial neoplasia (LGPIN), high-grade PIN (HGPIN), HGPIN with well-differentiated carcinoma (PIN + WDC), WDC (equivalent to grade 2/3 human PCa), and poorly-differentiated carcinoma (PDC-equivalent to grade 4/5 human PCa) revealed significantly higher Esr1 and Esr2 levels in HGPIN and significantly reduced levels in WDC, compared to respective age-matched control prostates. These patterns for the nuclear ERs were similar to the trend shown by E2 binding to the plasma membrane of the epithelial cells during PCa progression in TRAMP. E2 binding to epithelial cells (EpCAM+), though significantly higher in TPs displaying LGPIN, decreased significantly as the disease progressed to WDC. The study highlights a reduction in the epithelial ESR level with the PCa progression and this pattern was evident in both humans and TRAMP. These observations may have major implications in refining PCa therapeutics targeting ER.

Opposing roles for sMAdCAM and IL-15 in COVID-19 associated cellular immune pathology.

Immune cell dysregulation and lymphopenia characterize COVID-19 pathology in moderate to severe disease. While underlying inflammatory factors have been extensively studied, homeostatic and mucosal migratory signatures remain largely unexplored as causative factors. In this study, we evaluated the association of circulating IL-6, soluble mucosal addressin cell adhesion molecule (sMAdCAM), and IL-15 with cellular dysfunction characterizing mild and hypoxemic stages of COVID-19. A cohort of SARS-CoV-2 infected individuals (n = 130) at various stages of disease progression together with healthy controls (n = 16) were recruited from COVID Care Centres (CCCs) across Mumbai, India. Multiparametric flow cytometry was used to perform in-depth immune subset characterization and to measure plasma IL-6 levels. sMAdCAM, IL-15 levels were quantified using ELISA. Distinct depletion profiles, with relative sparing of CD8 effector memory and CD4+ regulatory T cells, were observed in hypoxemic disease within the lymphocyte compartment. An apparent increase in the frequency of intermediate monocytes characterized both mild as well as hypoxemic disease. IL-6 levels inversely correlated with those of sMAdCAM and both markers showed converse associations with observed lympho-depletion suggesting opposing roles in pathogenesis. Interestingly, IL-15, a key cytokine involved in lymphocyte activation and homeostasis, was detected in symptomatic individuals but not in healthy controls or asymptomatic cases. Further, plasma IL-15 levels negatively correlated with T, B, and NK count suggesting a compensatory production of this cytokine in response to the profound lymphopenia. Finally, higher levels of plasma IL-15 and IL-6, but not sMAdCAM, were associated with a longer duration of hospitalization.

Nanoparticle-eluting stents for coronary intervention: formulation, characterization, and in vitro evaluation.

Coronary artery disease (CAD) is currently a leading cause of death worldwide. In the history of percutaneous coronary intervention for the treatment of CAD, a drug-eluting stent (DES) is recognized as a revolutionary technology that has the unique ability to significantly reduce restenosis and provide both mechanical and biological solutions simultaneously to the target lesion. The aim of the research work was to design and fabricate DES coated with a nanoparticulate drug formulation. Sirolimus, an inhibitor of the smooth muscle cell (SMC) proliferation and migration, was encapsulated in polymeric nanoparticles (NPs). The NP formulation was characterized for various physicochemical parameters. Cell viability and cell uptake studies were performed using human coronary artery smooth muscle cells (HCASMCs). The developed NP formulation showed enhanced efficacy compared to plain drug solution and exhibited time-dependent uptake into the HCASMCs. The developed NP formulation was coated on the Flexinnium™ ultra-thin cobalt-chromium alloy coronary stent platform. The NP-coated stents were characterized for morphology and residual solvent analysis. In vitro drug release was also evaluated. Ex vivo arterial permeation was carried out to evaluate the NP uptake from the surface of the stents. The characterization studies together corroborated that the developed NP coated stent can be a promising replacement of the current DESs.

pH Stress Mediated Alteration in Protein Composition and Reduction in Cytotoxic Potential of Gardnerella vaginalis Membrane Vesicles.

The vagina of healthy women is predominantly colonized by lactobacilli but it also harbors a limited proportion of certain anaerobes such as Gardnerella vaginalis. An increase in G. vaginalis along with other anaerobes on account of perturbation in the vaginal microbiota is associated with bacterial vaginosis (BV). Although strategies adopted by G. vaginalis for survival and pathogenesis in a conducive environment (i.e., high vaginal pH, characteristic of BV) have been previously studied, the approaches potentially employed for adaptation to the low pH of the healthy vagina are unknown. In the present study, we investigated the effect of acidic stress on the modulation of the production and function of membrane vesicles (MVs) of G. vaginalis. pH stress led to a distortion of the bacterial cell morphology as well as an altered biogenesis of MVs, as revealed by transmission electron microscopy (TEM). Both qualitative and quantitative differences in protein content of MVs produced in response to pH stress were observed by flow cytometry. A significant change in the protein composition characterized by presence of chaperones despite a reduction in number of proteins was also noted in the stress induced MVs. Further, these changes were also reflected in the reduced cytotoxic potential toward vaginal epithelial cells. Although, these findings need to be validated in the in vivo settings, the modulation of G. vaginalis MV biogenesis, composition and function appears to reflect the exposure to acidic conditions prevailing in the host vaginal mileu in the absence of vaginal infection.

Increased frequency of Th17 cells and IL-17 levels are associated with low bone mineral density in postmenopausal women.

Osteoporosis is one of the chronic and often neglected bone diseases in aging postmenopausal women that affect the quality of life. Studies on ovariectomized mice models indicated the reciprocal role of Th17 cells and Treg cells in the aetiology of osteoporosis. While Th17 cells promote osteoclastogenesis, Treg cells exhibit anti-osteoclastogenic activity. This exploratory study aimed to determine the difference in the frequency of these T-cell subtypes in pre-and postmenopausal women and to examine their association with BMD. In our study, the frequency of Treg cells, analyzed by flow cytometry, did not differ between pre-and postmenopausal women. However, plasma levels of IL-10 along with IL-10+CD4+T cells were higher in post- compared to premenopausal women. The frequency of Th17 cells was higher in postmenopausal women irrespective of their BMD, however, only postmenopausal women with low BMD had elevated IL-17 levels and their T-scores were associated with Th17 frequency. Collectively, the results suggest that estrogen insufficiency in postmenopausal women may lead to increased Th17 cell frequency and elevated IL-17 levels which are associated with low BMD. This study highlights, Th17 cells and IL-17 as key players in the pathogenesis of osteoporosis and they can be the potential targets for immunotherapy in the treatment of osteoporosis.

Cycle threshold values in RT-PCR to determine dynamics of SARS-CoV-2 viral load: An approach to reduce the isolation period for COVID-19 patients.

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) has affected all inhabited continents, and India is currently experiencing a devastating second wave of coronavirus disease-2019 (COVID-19). Here, we examined the duration of clearance of SARS-CoV-2 in respiratory samples from 207 infected cases by real-time reverse-transcription polymerase chain reaction (RT-PCR). A substantial proportion of COVID-19 positive cases with cycle threshold (Ct) values more than or equal to 31 (45.7%) were subsequently tested negative for SARS-CoV-2 RNA within 7 days of initial detection of the viral load. A total of 60% of all the patients with COVID-19, irrespective of their Ct values, cleared SARS-CoV-2 RNA within 14 days of the initial detection. Longitudinal assessment of RT-PCR test results in individuals requiring 15-30 days to clear SARS-CoV-2 RNA showed a significant reduction of the viral load in samples with high or intermediate viral loads (Ct values ≤ 25 and between 26 and 30, respectively) but the follow-up group with low viral RNA (Ct values ≥ 31) exhibited a stable viral load. Together, these results suggest that COVID-19 positive cases with Ct values more than or equal to 31 require reduced duration to clear SARS-CoV-2, and thus, a shorter isolation period for this group might be considered to facilitate adequate space in the COVID Care Centres and reduce the burden on healthcare infrastructure.

sMAdCAM: IL-6 Ratio Influences Disease Progression and Anti-Viral Responses in SARS-CoV-2 Infection.

The role of sMAdCAM, an important gut immune migratory marker, remains unexplored in COVID-19 pathogenesis considering recent studies positing the gut as a sanctuary site for SARS-CoV-2 persistence. Thus, assimilating profiles of systemic inflammatory mediators with sMAdCAM levels may provide insights into the progression of COVID-19 disease. Also, the role of these markers in governing virus specific immunity following infection remains largely unexplored. A cohort (n = 84) of SARS-C0V-2 infected individuals included a group of in-patients (n = 60) at various stages of disease progression together with convalescent individuals (n = 24) recruited between April and June 2020 from Mumbai, India. Follow-up of 35 in-patients at day 7 post diagnosis was carried out. Th1/Th2/Th17 cytokines along with soluble MAdCAM (sMAdCAM) levels in plasma were measured. Also, anti-viral humoral response as measured by rapid antibody test (IgG, IgM), Chemiluminescent Immunoassay (IgG), and antibodies binding to SARS-CoV-2 proteins were measured by Surface Plasmon Resonance (SPR) from plasma. IL-6 and sMAdCAM levels among in-patients inversely correlated with one another. When expressed as a novel integrated marker-sMIL index (sMAdCAM/IL-6 ratio)-these levels were incrementally and significantly higher in various disease states with convalescents exhibiting the highest values. Importantly, sMAdCAM levels as well as sMIL index (fold change) correlated with peak association response units of receptor binding domain and fold change in binding to spike respectively as measured by SPR. Our results highlight key systemic and gut homing parameters that need to be monitored and investigated further to optimally guide therapeutic and prophylactic interventions for COVID-19.

Characteristics of Circulatory γδ T cells in Patients with Symptomatic Chronic Hepatitis B Infection.

Hepatitis B is a viral infection that can cause serious liver disease. Chronic hepatitis B (CHB) infection places individuals at higher risk of developing cirrhosis of the liver and hepatocellular cancer. Immune dysfunction, including altered distribution and functional status of T cell immunity, is a contributor to hepatitis B virus (HBV) pathogenesis. In this study, we examined the distribution of circulating γδ T cell subpopulations and levels of cell surface expression of suppressive markers on γδ T cells in individuals with CHB infection and clinical liver disease. A significantly higher proportion of terminally differentiated (TEMRA) (CD27-CD45RA+) γδ T cells along with significantly lower percentages of central memory (CD27+CD45RA-) and effector memory (CD27-CD45RA-) γδ T cells were observed in peripheral blood of these individuals. The expression of exhaustion markers-Tim-3 and Lag-3 was elevated in γδ T cells from CHB-infected individuals compared with healthy controls (HC) and blockade of these exhaustion markers resulted in restoration of interferon gamma (IFN-γ) secretion by γδ T cells. In addition, γδ T cells from CHB patients expressed increased levels of CD69, another important regulator of immune responses. Together, these results suggest that CHB patients with clinical sign of liver disease have TEMRA γδ T cells with a potentially exhausted phenotype that may in turn impair their immunoregulatory role and facilitate pathogenesis of CHB disease.

A retrospective analysis of COVID-19 diagnosis results obtained by rapid antigen tests and RT-PCR: Implications for disease management.

There is a need for understanding and establishment of the most appropriate testing algorithm for COVID-19 diagnosis in asymptomatic high-risk groups. Here, we present a retrospective analysis of RT-PCR results obtained from 412 cases tested negative for coronavirus disease 2019 (COVID-19) by rapid antigen testing method. Among 178 (43.2%) asymptomatic individuals, 44.9% of the high risk contacts, 12.2% of police custody individuals, 22.22% of the pregnant women and 33.33% of individuals hospitalised for preoperative or other medical conditions showed RT-PCR positivity. Our results suggest a need for focussed and intensive (multi-modality) testing in groups at high risk for SARS-CoV-2 infection.