Salma Sheikh‐Mohamed
A5010918864- SARS-CoV-2 and COVID-19 Research
- COVID-19 Clinical Research Studies
- Neuroinflammation and Neurodegeneration Mechanisms
- Respiratory viral infections research
- SARS-CoV-2 detection and testing
- Single-cell and spatial transcriptomics
- Multiple Sclerosis Research Studies
- HIV Research and Treatment
- Bacterial Infections and Vaccines
- 14-3-3 protein interactions
- Animal Virus Infections Studies
- Immune cells in cancer
- COVID-19 Impact on Reproduction
- Vaccine Coverage and Hesitancy
- Long-Term Effects of COVID-19
- Hepatitis C virus research
- Sphingolipid Metabolism and Signaling
- Complement system in diseases
University of Toronto
2019-2025
Although SARS-CoV-2 infects the upper respiratory tract, we know little about amount, type, and kinetics of antibodies (Ab) generated in oral cavity response to COVID-19 vaccination. We collected serum saliva samples from participants receiving two doses mRNA vaccines measured level anti-SARS-CoV-2 Ab. detected anti-Spike anti-Receptor Binding Domain (RBD) IgG IgA, as well anti-Spike/RBD associated secretory component most after dose 1. Administration a second boosted but not IgA response,...
Multiple sclerosis (MS) is characterized by demyelinated and inflammatory lesions in the brain spinal cord that are highly variable terms of cellular content. Here, we used imaging mass cytometry (IMC) to enable simultaneous 15+ proteins within staged MS lesions. To test potential for IMC discriminate between different types lesions, selected a case with severe rebound disease activity after natalizumab cessation. With post-acquisition analysis pipelines were able to: (1) Discriminate...
Abstract Prioritizing Ontario’s long-term care home (LTCH) residents for vaccination against severe acute respiratory syndrome coronavirus 2 has drastically reduced their disease burden; however, recent LTCH outbreaks of variants concern (VOCs) have raised questions regarding immune responses. In 198 residents, mRNA vaccine dose 1 elicited partial spike and receptor binding domain antibody responses, while the second a response at least equivalent to convalescent individuals in most...
Older individuals and people with HIV (PWH) were prioritized for COVID-19 vaccination, yet comprehensive studies of the immunogenicity these vaccines their effects on reservoirs are not available. Our study 68 PWH 23 HIV-negative participants aged 55 older post-three vaccine doses showed equally strong anti-spike IgG responses in serum saliva through week 48 from baseline, while salivary IgA low. had diminished live-virus neutralization after two doses, which 'rescued' post-booster....
The contributions of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-specific T cells to vaccine efficacy and durability are unclear. We investigated relationships between mRNA vaccine-induced spike-specific interferon- gamma (IFN-γ) interleukin-2 (IL-2) T-cell responses neutralizing antibody development in long-term care home staff doubly vaccinated with BNT162b2 or mRNA-1273. impacts pre-existing cross-reactive immunity on cellular humoral vaccination were additionally...
ABSTRACT Vaccination induced antibody and T-cell immune responses are important for systemic protection from COVID-19. Because SARS-CoV-2 infects is transmitted by oral-pharyngeal mucosa, we wished to test mucosal antibodies elicited natural infection or intramuscular vaccine injection. In a non-randomized observational study, measured against the RBD in plasma saliva convalescent vaccinated individuals tested their neutralizing potential using replication competent rVSV-eGFP-SARS-CoV-2. We...
Abstract Although SARS-CoV-2 infects the upper respiratory tract, we know little about amount, type, and kinetics of antibodies (Ab) generated at this site in response to intramuscular COVID-19 vaccination, whether these Ab protect against subsequent “breakthrough” infections. We collected longitudinal serum saliva samples from participants receiving two doses mRNA vaccines over a 6-month period measured relative level anti-Spike anti-Receptor Binding Domain (RBD) Ab. detected anti-Spike/RBD...
Abstract Although high titers of neutralizing Abs in human serum are associated with protection from reinfection by SARS-CoV-2, there is considerable heterogeneity serum-neutralizing against SARS-CoV-2 during convalescence between individuals. Standard live virus neutralization assays require inactivation serum/plasma prior to testing. In this study, we report that the convalescent sera were relatively consistent across all disease states except for severe COVID-19, which yielded...
Older individuals and people with HIV (PWH) were prioritized for COVID-19 vaccination, yet comprehensive studies of the immunogenicity these vaccines their effects on reservoirs are not available. We followed 68 PWH aged 55 older 23 age-matched HIV-negative 48 weeks from first vaccine dose, after total three doses. All antiretroviral therapy (cART) had different immune status, including responders (IR), non-responders (INR), low-level viremia (LLV). measured neutralizing Ab responses to...
ABSTRACT Our understanding of the quality cellular and humoral immunity conferred by COVID-19 vaccination alone versus plus SARS-CoV-2 breakthrough (BT) infection remains incomplete. While current (2023) immune landscape Canadians is complex, in late 2021 most had either just received a third dose vaccine, or their two primary series then experienced an Omicron BT. Herein we took advantage this coincident timing to contrast three doses vaccine results show that mild BT induces cell-mediated...
ABSTRACT Multiple Sclerosis (MS) is characterized by demyelinated and inflammatory lesions in the brain spinal cord. Lesions contain immune cells with variable phenotypes functions. Here we use imaging mass cytometry (IMC) to enable simultaneous of 15+ proteins within 11 staged MS lesions. Using this approach, demonstrated that majority demyelinating macrophage-like active were derived from resident microglial pool. Although CD8 + T predominantly infiltrated lesions, CD4 also abundant but...
Older individuals and people with HIV (PWH) were prioritized for COVID-19 vaccination, yet comprehensive studies of the immunogenicity these vaccines their effects on reservoirs are not available. Our study 68 PWH 23 HIV-negative participants aged 55 older post-three vaccine doses showed equally strong anti-spike IgG responses in serum saliva through week 48 from baseline, while salivary IgA low. had diminished live-virus neutralization after two doses, which ‘rescued’ post-booster....
Abstract In light of ongoing booster vaccination campaigns, one recurring question is whether individuals infected with SARS-CoV-2 should still receive a dose if they were after completing their primary series. We aimed to assess the intensity functional humoral and cellular immune responses induced by breakthrough infections during B.1.1.529 wave in Canada compared who received three doses vaccine. Because hybrid immunity has been shown induce particularly potent immunity, we hypothesized...
Sunday, April 26April 14, 2020Free AccessMultiplex Imaging of Immune Cells in the Multiple Sclerosis Brain (4485)Valeria Ramaglia, Salma Sheikh-Mohamed, Karen Legg, Calvin Park, Olga Rojas, Stephanie Zandee, Fred Fu, … Show All , Ornatsky, Eric Swanson, David Pitt, Alexandre Prat, Trevor McKee, and Jennifer Gommerman FewerAuthors Info & AffiliationsApril 2020 issue94 (15_supplement)https://doi.org/10.1212/WNL.94.15_supplement.4485 Letters to Editor
Abstract Neutralizing activity found in the blood following intramuscular vaccination protects against systemic disease from SARS-CoV-2 infection. Mild breakthrough mucosal infections vaccinated individuals can contribute to transmission chains of infection, and as such contribution immunity is important understand. We assessed vesicular stomatitis virus (VSV) SPIKE protein neutralization activities well anti-viral spike RBD IgG IgA isotype antibody binding, saliva who had recovered...
Abstract SARS-CoV-2 is a novel respiratory virus that has quickly spread across the globe. The uses protein called Spike and its associated receptor binding domain (RBD) to interact with angiotensin converting enzyme-2 (ACE-2) on surface of epithelial cells in tract. Although definite correlate protection against COVID-19 yet emerge, many studies have quantified anti-Spike anti-RBD IgG antibody (Ab) levels, as well neutralizing Ab blood ascertain immunity. This approach misses out are...