Adaptive Reconfiguration of Natural Killer Cells in HIV-1 Infection

Human cytomegalovirus (HCMV) co-infection is highly prevalent within HIV-1 cohorts and is an important cofactor in driving ongoing immune activation, even during effective antiretroviral treatment. HCMV infection has recently been associated with expansion of adaptive-like natural killer (NK) cells, which harbor epigenetic alterations that impact on their cellular function and phenotype. The influence of HCMV co-infection on the considerable heterogeneity among NK cells and their functional responses to different stimuli was assessed in a cohort of HIV-1-infected individuals sampled during different stages of infection, compared with healthy subjects stratified according to HCMV serostatus. Our data demonstrate a reshaping of the NK cell pool in HIV-1 infection of HCMV-seropositive individuals, with an accentuated peripheral transition of CD56dim NK cells toward a mature CD57+ CD85j+ NKG2C+ NKG2A− phenotype. Lack of PLZF further distinguishes adaptive NK cells from other NK cells expressing CD57 or NKG2C. PLZF− NK cells from HIV-infected individuals had high expression of CD2, were Siglec-7 negative and exhibited downregulation of key signaling molecules, SYK and FcεRI-γ, overwhelmingly displaying features of adaptive NK cells that correlated with HCMV serum Ab levels. Notably this adaptive-like signature was detected during early HIV-1 infection and persisted during treatment. Adaptive-like NK cell subsets in HIV-1-infected individuals displayed enhanced IFN-γ production following Fc receptor triggering compared with their conventional NK cell counterparts, and their ability to produce TNF-α and degranulate was preserved. Together, these data suggest that HMCV infection/reactivation, a hallmark of HIV-1 infection, plays a role in driving a relative expansion of NK cells with adaptive features during HIV-1 infection. The identification of selective NK subsets with retained effector activity in HIV-1-infected subjects raises the possibility of developing therapeutic strategies that exploit specific NK subpopulations to achieve better HIV-1 control

Birth prevalence of anorectal malformations in England and 5-year survival: a national birth cohort study

OBJECTIVE: To determine the birth prevalence, maternal risk factors and 5-year survival for isolated and complex anorectal malformations. DESIGN: National birth cohort using hospital admission data and death records. SETTING: All National Health Service England hospitals. PATIENTS: Live-born singletons delivered from 2002 through 2018, with evidence in the first year of life of a diagnosis of an anorectal malformation and repair during a hospital admission, or anorectal malformation recorded on the death certificate. Cases were further classified as isolated or complex depending on the presence of additional anomalies. MAIN OUTCOME MEASURES: Birth prevalence of anorectal malformations per 10 000 live births, risk ratios for isolated and complex anorectal malformation by maternal, infant and birth characteristics, and 5-year survival. RESULTS: We identified 3325 infants with anorectal malformations among 9 474 147 live-born singletons; 61.7% (n=2050) of cases were complex. Birth prevalence was 3.5 per 10 000 live births (95% CI 3.4 to 3.6). Complex anorectal malformations were associated with maternal age extremes after accounting for other sociodemographic factors. Compared with maternal ages 25-34 years, the risk of complex anorectal malformations was 31% higher for ≥35 years (95% CI 17 to 48) and 13% higher for ≤24 years (95% CI 0 to 27). Among 2376 anorectal malformation cases (n=1450 complex) born from 2002 through 2014, 5-year survival was lower for complex (86.9%; 95% CI 85.1% to 88.5%) than isolated anorectal malformations (98.2%; 95% CI 97.1% to 98.9%). Preterm infants with complex anorectal malformations had the lowest survival (73.4%; 95% CI 68.1% to 78.0%). CONCLUSIONS: Differences in maternal risk factors for isolated and complex anorectal malformations may reflect different underlying mechanisms for occurrence. Five-year survival is high but lowest for preterm children with complex anorectal malformations

Interferon Alpha Induces Sustained Changes in NK Cell Responsiveness to Hepatitis B Viral Load Suppression In Vivo

This work was supported by funding from The NIHR Academic Clinical Fellowship scheme and a Wellcome Trust Clinical Research Training fellowship (107389/Z/15/Z) awarded to USG; a Wellcome Trust Senior Investigator award (101848/Z/ 13/Z) to MKM and a Barts and The London Charity award (No. 723/1795) to PTFK

TRAIL regulatory receptors constrain human hepatic stellate cell apoptosis

This work was funded by UCLH NIHR BRC (sample collection), Wellcome Trust Investigator award (MKM) and Clinical Research Training Fellowship (USG); Medical Research Council grant (MKM) and Clinician Scientist Fellowship (DP); EASL fellowship (IO); National Health and Medical Research Council Australia (KPS)

Subordinate Effect of -21M HLA-B Dimorphism on NK Cell Repertoire Diversity and Function in HIV-1 Infected Individuals of African Origin

Natural Killer (NK) cells play an important role in antiviral defense and their potent effector function identifies them as key candidates for immunotherapeutic interventions in chronic viral infections. Their remarkable functional agility is achieved by virtue of a wide array of germline-encoded inhibitory and activating receptors ensuring a self-tolerant and tunable repertoire. NK cell diversity is generated by a combination of factors including genetic determinants and infections/environmental factors, which together shape the NK cell pool and functional potential. Recently a genetic polymorphism at position -21 of HLA-B, which influences the supply of HLA-E binding peptides and availability of HLA-E for recognition by the inhibitory NK cell receptor NKG2A, was shown to have a marked influence on NK cell functionality in healthy human cytomegalovirus (HCMV) seronegative Caucasian individuals. In this study, -21 methionine (M)-expressing alleles supplying HLA-E binding peptides were largely poor ligands for inhibitory killer immunoglobulin-like receptors (KIRs), and a bias to NKG2A-mediated education of functionally-potent NK cells was observed. Here, we investigated the effect of this polymorphism on the phenotype and functional capacity of peripheral blood NK cells in a cohort of 36 African individuals with human immunodeficiency virus type 1 (HIV-1)/HCMV co-infection. A similarly profound influence of dimorphism at position -21 of HLA-B on NK cells was not evident in these subjects. They predominantly expressed African specific HLA-B and -C alleles that contribute a distinct supply of NKG2A and KIR ligands, and these genetic differences were compounded by the marked effect of HIV-1/HCMV co-infection on NK cell differentiation. Together, these factors resulted in a lack of correlation of the HLA-B -21 polymorphism with surface abundance of HLA-E and loss of the NK cell functional advantage in subjects with -21M HLA-B alleles. Instead, our data suggest that during HIV/HCMV co-infection exposure of NK cells to an environment that displays altered HLA-E ligands drives adaptive NKG2C+ NK cell expansions influencing effector responses. Increased efforts to understand how NK cells are functionally calibrated to self-HLA during chronic viral infections will pave the way to developing targeted therapeutic interventions to overcome the current barriers to enhancing immune-based antiviral control

Effect of Advanced Glycation End Products on Human Thyroglobulin's Antigenicity as Identified by the Use of Sera from Patients with Hashimoto's Thyroiditis and Gestational Diabetes Mellitus

Advanced glycation end products (AGEs) are formed on proteins after exposure to high concentrations of glucose and modify protein's immunogenicity. Herein, we investigated whether the modification of thyroglobulin (Tg) by AGEs influences its antigenicity and immunogenicity. Human Tg was incubated in vitro with increasing concentrations of D-glucose-6-phosphate in order to produce Tgs with different AGE content (AGE-Tg). Native Tg and AGE-Tgs were used in ELISA to assess the serum antibody reactivity of two patient groups, pregnant women with gestational diabetes (GDM), and patients with Hashimoto's thyroiditis (HT). We produced in vitro AGE-Tg with low and high AGE content, 13 and 49 AGE units/mg Tg, respectively. All HT patients' sera presented the same antibody reactivity profile against native Tg and AGE-Tgs, indicating that the modification of Tg by AGEs did not alter its antigenicity. Similarly, the GDM patients' sera did not discriminate among the two forms of Tg, native or artificially glycated, suggesting that the modification of Tg by AGEs might not alter its immunogenicity. The modification of Tg by AGEs has no obvious effect on neither its antigenicity nor, most likely, its immunogenicity. It seems that other Tg modifications might account for the production of aTgAbs in patients with GDM

Prevalence of COVID-19-related risk factors and risk of severe influenza outcomes in cancer survivors: A matched cohort study using linked English electronic health records data.

BACKGROUND: People with active cancer are recognised as at risk of COVID-19 complications, but it is unclear whether the much larger population of cancer survivors is at elevated risk. We aimed to address this by comparing cancer survivors and cancer-free controls for (i) prevalence of comorbidities considered risk factors for COVID-19; and (ii) risk of severe influenza, as a marker of susceptibility to severe outcomes from epidemic respiratory viruses. METHODS: We included survivors (≥1 year) of the 20 most common cancers, and age, sex and general practice-matched cancer-free controls, derived from English primary care data linked to cancer registrations, hospital admissions and death registrations. Comorbidity prevalences were calculated 1 and 5 years from cancer diagnosis. Risk of hospitalisation or death due to influenza was compared using Cox models adjusted for baseline demographics and comorbidities. FINDINGS: 108,215 cancer survivors and 523,541 cancer-free controls were included. Cancer survivors had more diabetes, asthma, other respiratory, cardiac, neurological, renal, and liver diseases, and less obesity, compared with controls, but there was variation by cancer site. There were 205 influenza hospitalisations/deaths, with cancer survivors at higher risk than controls (adjusted HR 2.78, 95% CI 2.04-3.80). Haematological cancer survivors had large elevated risks persisting for >10 years (HR overall 15.17, 7.84-29.35; HR >10 years from cancer diagnosis 10.06, 2.47-40.93). Survivors of other cancers had evidence of raised risk up to 5 years from cancer diagnosis only (HR >5 years 2.22, 1.31-3.74). INTERPRETATION: Risks of severe COVID-19 outcomes are likely to be elevated in cancer survivors. This should be taken into account in policies targeted at clinical risk groups, and vaccination for both influenza, and, when available, COVID-19, should be encouraged in cancer survivors