26 research outputs found

    IGG3 Subclass Antibodies Recognize Antigenically Drifted Influenza Viruses and SARS-CoV-2 Variants Through Efficient Bivalent Binding

    Get PDF
    The constant domains of antibodies are important for effector functions, but less is known about how they can affect binding and neutralization of viruses. Here, we evaluated a panel of human influenza virus monoclonal antibodies (mAbs) expressed as IgG1, IgG2, or IgG3. We found that many influenza virus-specific mAbs have altered binding and neutralization capacity depending on the IgG subclass encoded and that these differences result from unique bivalency capacities of the subclasses. Importantly, subclass differences in antibody binding and neutralization were greatest when the affinity for the target antigen was reduced through antigenic mismatch. We found that antibodies expressed as IgG3 bound and neutralized antigenically drifted influenza viruses more effectively. We obtained similar results using a panel of SARS-CoV-2-specific mAbs and the antigenically advanced B.1.351 and BA.1 strains of SARS-CoV-2. We found that a licensed therapeutic mAb retained neutralization breadth against SARS-CoV-2 variants when expressed as IgG3, but not IgG1. These data highlight that IgG subclasses are not only important for fine-tuning effector functionality but also for binding and neutralization of antigenically drifted viruses

    Risk of sepsis and pneumonia in patients initiated on SGLT2 inhibitors and DPP-4 inhibitors

    Get PDF
    Aim: The organ protective effects of sodium-glucose cotransporter 2 (SGLT2) inhibitors may be beneficial against infectious complications. This real-world study aims to compare the risk of pneumonia and sepsis between SGLT2 inhibitors and dipeptidyl peptidase 4 (DPP-4) inhibitors in patients with type 2 diabetes. Methods: Using a territory-wide clinical registry in Hong Kong (Clinical Data Analysis and Reporting System [CDARS]), we included patients initiated on SGLT2 inhibitors or DPP-4 inhibitors between January 01, 2015 and December 31, 2019 through 1:2 propensity score matching. The primary outcomes were incident events of pneumonia, sepsis and the related mortality. Cox proportional hazards analysis was used to compare the risk of incident pneumonia and sepsis for SGLT2 inhibitors versus DPP-4 inhibitors. Results: After propensity score matching, 10,706 new users of SGLT2 inhibitors and 18,281 new users of DPP-4 inhibitors were included. The mean age of all eligible subjects were 60 years (SD 11.07) and 61.1% were male. There were 309 pneumonia events [incidence rate per 1000 person-years (IR) = 11.38] among SGLT2 inhibitors users and 961 events (IR = 20.45) among DPP-4 inhibitors users, with lower risk of pneumonia among SGLT2 inhibitors users (adjusted HR 0.63 [95%CI 0.55–0.72], p<0.001). Similarly, SGLT2 inhibitors users had lower incidence of sepsis [164 (IR=6.00) vs. 610 (IR=12.88) events] as well as associated risk of incident sepsis (HR 0.52 [95% CI 0.44–0.62], p<0.001), compared to DPP-4 inhibitors users. Outcome analyses showed that SGLT2 inhibitors were associated with lower risk of pneumonia-related death (HR 0.41 [95%CI 0.29–0.58], p<0.001), sepsis-related death (HR 0.39 [95%CI 0.18–0.84], p<0.05), and infection-related death (HR 0.43 [95%CI 0.32–0.57], p<0.001), compared to DPP-4 inhibitors users. Results were consistent when stratified by age, sex, pre-existing cardiovascular disease, and type of SGLT2 inhibitors. Conclusion: We provide real-world evidence that irrespective of age, sex, prior-existing cardiovascular disease, or type of SGLT2 inhibitors used, patients with type 2 diabetes initiated on SGLT2 inhibitors have lower incidence of pneumonia and sepsis as well as mortality risk associated with pneumonia, sepsis, and infectious diseases, compared with those initiated on DPP-4 inhibitors

    Randomized controlled trial of transcutaneous electrical nerve stimulation for pain relief during transvaginal oocyte retrieval using conscious sedation: study protocol for a randomized controlled trial

    No full text
    Abstract Background Transvaginal oocytes retrieval is an essential step in in-vitro fertilization treatment. There are different pain relief methods, but none has been shown to be superior than the others. Transcutaneous electrical nerve stimulation (TENS) is a non-pharmacological and non-invasive pain relief method. This study aims to compare the pain levels experienced by the women using the conscious sedation and those who had TENS in addition to conscious sedation. Methods and analysis This is a double-blinded randomized trial that will be carried out in a university-assisted conception unit. Women who will undergo oocyte retrieval under conscious sedation will be recruited. After randomization, women will be allocated to either the active TENS group or placebo TENS group (the TENS machine will not emit active impulse), in addition to the paracervical block and conscious sedation. The primary outcome is pain levels of women during the retrieval assessed by the visual analog scale. Secondary outcomes include satisfaction of women and postoperative side effects. Discussion TENS is an effective non-pharmacological and non-invasive method for pain relief in a number of clinical conditions. Both women and assisted conception unit can benefit if the addition of non-invasive, simple, and low-cost TENS application is proven to be superior than using conscious sedation and paracervical block alone. Trial registration ClinicalTrials.gov, NCT03472430. Registered on 3 May 2018

    Frequent Development of Broadly Neutralizing Antibodies in Early Life in a Large Cohort of Children With Human Immunodeficiency Virus

    No full text
    BackgroundRecent studies have indicated that broadly neutralizing antibodies (bnAbs) in children may develop earlier after human immunodeficiency virus (HIV) infection compared to adults.MethodsWe evaluated plasma from 212 antiretroviral therapy-naive children with HIV (1-3 years old). Neutralization breadth and potency was assessed using a panel of 10 viruses and compared to adults with chronic HIV. The magnitude, epitope specificity, and immunoglobulin (Ig)G subclass distribution of Env-specific antibodies were assessed using a binding antibody multiplex assay.ResultsOne-year-old children demonstrated neutralization breadth comparable to chronically infected adults, whereas 2- and 3-year-olds exhibited significantly greater neutralization breadth (P = .014). Likewise, binding antibody responses increased with age, with levels in 2- and 3-year-old children comparable to adults. Overall, there was no significant difference in antibody specificities or IgG subclass distribution between the pediatric and adult cohorts. It is interesting to note that the neutralization activity was mapped to a single epitope (CD4 binding site, V2 or V3 glycans) in only 5 of 38 pediatric broadly neutralizing samples, which suggests that most children may develop a polyclonal neutralization response.ConclusionsThese results contribute to a growing body of evidence suggesting that initiating HIV immunization early in life may present advantages for the development of broadly neutralizing antibody responses

    ISIS: A multilingual spoken dialog system developed with CORBA and KQML agents

    No full text
    ISIS, which abbreviates Intelligent Speech for Information Systems, is a trilingual spoken dialog system (SDS) for the financial domain. It handles two dialects of Chinese (Cantonese and Putonghua), as well as English the predominant languages in our region. The system supports spoken language queries regarding stock market information and simulated personal portfolios. Real-time information is retrieved directly from a dedicated Reuters satellite feed. ISIS provides a system test-bed for our work in multilingual speech recognition and generation, speaker authentication, language understanding and dialog modeling. Furthermore, ISIS supports our initial explorations in: (i) CORBA&apos;s interoperability and scalability for SDS development; in conjunction with (ii) asynchronous human-computer interaction by delegation to KQML software agents..

    Donor-Derived Genotype 4 Hepatitis E Virus Infection, Hong Kong, China, 2018

    No full text
    Hepatitis E virus (HEV) genotype 4 (HEV-4) is an emerging cause of acute hepatitis in China. Less is known about the clinical characteristics and natural history of HEV-4 than HEV genotype 3 infections in immunocompromised patients. We report transmission of HEV-4 from a deceased organ donor to 5 transplant recipients. The donor had been viremic but HEV IgM and IgG seronegative, and liver function test results were within reference ranges. After a mean of 52 days after transplantation, hepatitis developed in all 5 recipients; in the liver graft recipient, disease was severe and with progressive portal hypertension. Despite reduced immunosuppression, all HEV-4 infections progressed to persistent hepatitis. Four patients received ribavirin and showed evidence of response after 2 months. This study highlights the role of organ donation in HEV transmission, provides additional data on the natural history of HEV-4 infection, and points out differences between genotype 3 and 4 infections in immunocompromised patients

    Conjugation of HIV-1 envelope to hepatitis B surface antigen alters vaccine responses in rhesus macaques

    No full text
    Abstract An effective HIV-1 vaccine remains a critical unmet need for ending the AIDS epidemic. Vaccine trials conducted to date have suggested the need to increase the durability and functionality of vaccine-elicited antibodies to improve efficacy. We hypothesized that a conjugate vaccine based on the learned response to immunization with hepatitis B virus could be utilized to expand T cell help and improve antibody production against HIV-1. To test this, we developed an innovative conjugate vaccine regimen that used a modified vaccinia virus Ankara (MVA) co-expressing HIV-1 envelope (Env) and the hepatitis B virus surface antigen (HBsAg) as a prime, followed by two Env–HBsAg conjugate protein boosts. We compared the immunogenicity of this conjugate regimen to matched HIV-1 Env-only vaccines in two groups of 5 juvenile rhesus macaques previously immunized with hepatitis B vaccines in infancy. We found expansion of both HIV-1 and HBsAg-specific circulating T follicular helper cells and elevated serum levels of CXCL13, a marker for germinal center activity, after boosting with HBsAg–Env conjugate antigens in comparison to Env alone. The conjugate vaccine elicited higher levels of antibodies binding to select HIV Env antigens, but we did not observe significant improvement in antibody functionality, durability, maturation, or B cell clonal expansion. These data suggests that conjugate vaccination can engage both HIV-1 Env and HBsAg specific T cell help and modify antibody responses at early time points, but more research is needed to understand how to leverage this strategy to improve the durability and efficacy of next-generation HIV vaccines

    Clinical characteristics of different groups.

    No full text
    AimsA subset of IgA nephropathy (IgAN) patients exhibiting minimal change disease (MCD) like features present with nephrotic-range proteinuria and warrants immunosuppressive therapy (IST). However, the diagnosis of MCD-like IgAN varied by reports. We aimed to identify the key pathological features of MCD-like IgAN.MethodsIn this cohort, 228 patients had biopsy-proven IgAN from 2009 to 2021, of which 44 without segmental sclerosis were enrolled. Patients were classified into segmental ( 50%) foot process effacement (FPE) groups. We further stratified them according to the usage of immunosuppressant therapy after biopsy. Clinical manifestations, treatment response, and renal outcome were compared.Results26 cases (59.1%) were classified as segmental FPE group and 18 cases (40.9%) as global FPE group. The global FPE group had more severe proteinuria (11.48 [2.60, 15.29] vs. 0.97 [0.14, 1.67] g/g, p = 0.001) and had a higher proportion of complete remission (81.8% vs. 20%, p = 0.018). In the global FPE group, patients without IST experienced more rapid downward eGFR change than the IST-treated population (-0.38 [-1.24, 0.06] vs. 1.26 [-0.17, 3.20]mL/min/1.73 m2/month, p = 0.004).ConclusionsThe absence of segmental sclerosis and the presence of global FPE are valuable pathological features that assist in identifying MCD-like IgAN.</div
    corecore