A5020455985- SARS-CoV-2 and COVID-19 Research
- COVID-19 Clinical Research Studies
- Cytomegalovirus and herpesvirus research
- Influenza Virus Research Studies
- Herpesvirus Infections and Treatments
- HIV Research and Treatment
- Reproductive System and Pregnancy
- Immunotherapy and Immune Responses
- Polyomavirus and related diseases
- Transplantation: Methods and Outcomes
- Respiratory viral infections research
- Animal Virus Infections Studies
- Immune Cell Function and Interaction
- Immune Response and Inflammation
- SARS-CoV-2 detection and testing
- Reproductive tract infections research
- HIV/AIDS Research and Interventions
- Viral-associated cancers and disorders
- Long-Term Effects of COVID-19
- Toxoplasma gondii Research Studies
- COVID-19 Impact on Reproduction
- COVID-19 diagnosis using AI
- Hematopoietic Stem Cell Transplantation
- Drug-Induced Adverse Reactions
- Viral Infections and Immunology Research
University Health Network
2016-2025
University of Toronto
2016-2025
Toronto General Hospital
2024-2025
Toronto General Hospital Research Institute
2025
Centre Hospitalier de l’Université de Montréal
2019-2021
Université de Montréal
2019
McMaster University
2010-2018
McMaster University Medical Centre
2014-2015
Discovery Centre
2011
Solid organ transplant recipients are at high risk of severe disease from COVID-19. We assessed the immunogenicity mRNA-1273 vaccine using a combination antibody testing, surrogate neutralization assays, and T cell assays. Patients were immunized with two doses after each dose above tests. CD4+ CD8+ responses in subset flow-cytometry. A total 127 patients enrolled which 110 provided serum all time points. positive anti-RBD was seen 5.0% one 34.5% doses. Neutralizing present 26.9%. Of note,...
The annual standard-dose (SD) influenza vaccine has suboptimal immunogenicity in solid organ transplant recipients (SOTRs). Influenza that contains higher doses of antigens may lead to greater this population.We conducted a randomized, double-blind trial compare the safety and 2016-2017 high-dose (HD; FluzoneHD, Sanofi) vs SD (Fluviral, GSK) adult SOTRs. Preimmunization 4-week postimmunization sera underwent strain-specific hemagglutination inhibition assay.We enrolled 172 patients who...
Seasonal influenza infection may cause significant morbidity and mortality in transplant recipients. The purpose of this study was to assess the epidemiology symptomatic posttransplant determine risk factors for severe disease.Twenty centers United States, Canada, Spain prospectively enrolled solid organ (SOT) or hematopoietic stem cell (HSCT) recipients with microbiologically confirmed influenza over 5 consecutive years (2010-2015). Demographics, microbiology data, outcomes were collected....
Although women constitute half of all HIV-1-infected people worldwide (UNAIDS World AIDS Day Report, 2011), the earliest events in female reproductive tract (FRT) during heterosexual HIV-1 transmission are poorly understood. Recently, we demonstrated that could directly impair mucosal epithelial barrier FRT. This suggested envelope glycoprotein gp120 was being recognized by a membrane receptor on genital cells, leading to innate immune activation. In this study, report pattern-recognition...
Inflammation is a known mechanism that facilitates HIV acquisition and the spread of infection. In this study, we evaluated whether curcumin, potent safe anti-inflammatory compound, could be used to abrogate inflammatory processes facilitate HIV-1 in female genital tract (FGT) contribute amplification. Primary, human epithelial cells (GECs) were pretreated with curcumin exposed or glycoprotein 120 (gp120), both which have been shown disrupt tight junction proteins, including ZO-1 occludin....
The SARS-CoV-2 virus Omicron variant has now supplanted wild-type as the dominant circulating strain globally. Three doses of mRNA COVID-19 vaccine are recommended for transplant recipients their primary series. However, immunogenicity vaccines they specifically relate to not well studied. We analyzed Omicron-specific neutralization in after three-doses mRNA-1273 vaccine. Neutralization was determined using a spike pseudotyped lentivirus assay with constructs and Delta variants. A total 60...
COVID-19 is more severe in transplant recipients. Variants of concern have supplanted wild-type virus. In recipients, data are limited on 2-dose or 3-dose vaccine immunogenicity against variant viruses.To assess neutralizing antibody responses SARS-CoV-2 variants recipients after 2 and 3 doses.Secondary analysis a randomized, double-blind, controlled trial third dose mRNA-1273 versus placebo. (ClinicalTrials.gov: NCT04885907).Single-center program.Organ recipients.Third placebo.Sera were...
In allogeneic stem cell transplant (Allo-SCT) recipients, the cell-mediated and humoral immunogenicity of 3-dose SARS-CoV-2 vaccination schedule has not been investigated in prospective studies. a cohort, we recruited 122 Allo-SCT recipients since August 2021, when Ontario began offering vaccine for recipients. We determined immunity adverse effects SARS-COV-2 analysis (n = 95), median (interquartile range [IQR]) antibody titer against receptor-binding domain (RBD) spike (S) protein after...
Solid organ transplant recipients (SOTRs) are predisposed to infection due the need for lifelong immunosuppression, although tools measure overall degree of immunosuppression limited. In this study, we used a novel global cell-mediated immunity (CMI) assay quantify and predict subsequent infections. Consecutive SOTRs were enrolled provided whole blood conduct CMI (QuantiFERON Monitor) at 1, 3, 6 months posttransplant. The measures plasma interferon gamma (IFN-γ) levels after stimulation with...
Background. Letermovir, a new viral terminase complex inhibitor, has been approved for the prevention of cytomegalovirus (CMV) infection in hematopoietic stem cell transplant patients. However, data on efficacy and safety letermovir treatment CMV recipients remain scarce. Methods. We performed single-center retrospective study organ who received from November 2017 to October 2018. Results. Six patients were included, 5 evaluable. All context refractory or resistant including asymptomatic...
Immunization of varicella-zoster virus (VZV)-seronegative solid organ transplant (SOT) patients using the live-attenuated varicella vaccine is generally contraindicated, leaving no widely applicable immunization option. The recombinant subunit herpes zoster (RZV) indicated for VZV-seropositive persons to prevent shingles but could potentially also protect VZV-seronegative against varicella. We performed a safety and immunogenicity evaluation RZV in SOT recipients as an option...
Abstract Little is known about cell-mediated immune responses to natural influenza infection in solid organ transplant (SOT) patients. The aim of our study was evaluate the CD4 + and CD8 A B a cohort SOT We collected peripheral blood mononuclear cells at diagnosis four weeks later from 31 patients during 2017–2018 season. Infection-elicited influenza-specific T-cell were measured using flow cytometry intracellular cytokine staining compared following vaccine Natural associated with...
Abstract Immunocompromised patients are predisposed to severe COVID-19. Here we compare homotypic and heterotypic humoral cellular immune responses Omicron BA.1 in organ transplant across a diverse clinical spectrum. We perform variant-specific pseudovirus neutralization assays for D614G, Omicron-BA.1, -BA.2, Delta variants. also measure poly-and monofunctional T-cell ancestral SARS-CoV-2 peptide pools. identify that partially or fully-vaccinated recipients after infection with have the...
Solid organ transplant (SOT) recipients are at risk for severe coronavirus disease 2019 (COVID-19), despite vaccination. Our study aimed to elucidate COVID-19 vaccine immunogenicity and evaluate adverse events such as hospitalization, rejection, breakthrough infection in a SOT cohort.We performed prospective, observational on 539 adult (age ≥18 years old) recruited from 7 Canadian centers. Demographics including characteristics, types, immunosuppression infection, rejection were recorded....
Although clinical and experimental evidence indicates that female sex hormones hormonal contraceptives regulate susceptibility to human immunodeficiency virus type 1 (HIV-1) infection, the underlying mechanism remains unknown. Genital epithelial cells (GECs) are first encounter HIV during sexual transmission their interaction with may determine outcome of exposure. This is report uptake by GECs increased significantly in presence contraceptive medroxyprogesterone acetate (MPA) progesterone...
Abstract Background In solid organ transplant (SOT) recipients, the primary vaccination series against Coronavirus Disease 2019 is 3 doses followed by boosters. We determined whether a fourth dose booster induced Omicron BA.4/5 neutralizing antibodies (nAbs) and T cells in large multicenter cohort study. Methods Serum was collected 4–6 weeks post-third post-fourth of messenger RNA vaccine 222 SOT recipients. nAbs were measured using pseudovirus neutralization assay that targeted spike...