Biology subjects

Mohamath, R.

Publications and source records attributed to Mohamath, R..

3 recordsLinked to original sources

bioRxiv2025

The ID93 + GLA-3M-052-LS vaccine candidate elicits mucosal and systemic immunogenicity and protective efficacy against Mycobacterium tuberculosis challenge in BCG-primed Collaborative Cross inbred mice

New vaccine approaches are needed against tuberculosis (TB). We sought to optimize mucosal immunogenicity and protective efficacy by modulating the adjuvant component and route of immunization of a next-generation TB vaccine using the recombinant TB vaccine antigen (Ag) ID93. ID93-specific mucosal and systemic immunogenicity and protective efficacy were assessed in the Collaborative Cross 004 mouse strain, a mouse strain susceptible to Mycobacterium tuberculosis (Mtb) infection, as a suitable model of Mtb susceptible populations. Immunogenicity data from various vaccine candidates were used to select lead vaccine candidates with the most preferred immunostimulatory profiles using a pre-determined desirability index. A liposomal adjuvant system containing synthetic TLR4 and TLR7/8 ligands (GLA-3M-052-LS), administered by a heterologous intramuscular-intranasal regimen, induced an optimal comprehensive immune response profile including high levels of mucosal antibody and Th1 CD4+ T cells in the lungs. In BCG-primed mice, immunization with intramuscular followed by intranasal ID93 + GLA-3M-052-LS boosts significantly reduced Mtb burden in the lungs after challenge vs. BCG vaccinated mice alone. Thus, ID93 + GLA-3M-052-LS represents a promising next-generation TB vaccine candidate suitable for testing in additional preclinical models.

immunology↗

bioRxiv2022

An intranasal self-amplifying RNA SARS-CoV-2 vaccine produces durable respiratory and systemic immunity

While mRNA vaccines have been effective in combating SARS-CoV-2, waning of vaccine-induced antibody responses and lack of vaccine-induced respiratory tract immunity contribute to ongoing infection and transmission. In this work, we compare and contrast intranasal (i.n.) and intramuscular (i.m.) administration of a SARS-CoV-2 self-amplifying RNA (saRNA) vaccine delivered by a nanostructured lipid carrier (NLC). Both i.m. and i.n. vaccines induce potent systemic serum neutralizing antibodies, bone marrow-resident IgG-secreting cells, and splenic T cell responses. The i.n. vaccine additionally induces robust respiratory mucosal immune responses, including SARS-CoV-2-reactive lung-resident memory and lung-homing T cell populations. As a booster following previous i.m. vaccination, the i.n. vaccine also elicits the development of mucosal virus-specific T cells. Both the i.m. and i.n. administered vaccines durably protect hamsters from infection-associated morbidity upon viral challenge, significantly reducing viral loads and preventing challenged hamsters from transmitting virus to naive cagemates. This saRNA-NLC vaccines potent systemic immunogenicity, and additional mucosal immunogenicity when delivered i.n., may be key for combating SARS-CoV-2 and other respiratory pathogens.

immunology↗

bioRxiv2022

A self-amplifying RNA vaccine against COVID-19 with long-term room-temperature stability

mRNA vaccines were the first to be authorized for use against SARS-CoV-2 and have since demonstrated high efficacy against serious illness and death. However, limitations in these vaccines have been recognized due to their requirement for cold storage, short durability of protection, and lack of access in low-resource regions. We have developed an easily-manufactured, potent self-amplifying RNA (saRNA) vaccine against SARS-CoV-2 that is stable at room temperature. This saRNA vaccine is formulated with a nanostructured lipid carrier (NLC), providing enhanced stability, improved manufacturability, and protection against degradation. In preclinical studies, this saRNA/NLC vaccine induced strong humoral immunity, as demonstrated by high pseudovirus neutralization titers to the Alpha, Beta, and Delta variants of concern and induction of long-lived bone marrow-resident antibody secreting cells. Robust Th1-biased T-cell responses were also observed after prime or homologous prime-boost in mice. Notably, the saRNA/NLC platform demonstrated thermostability at room temperature for at least 6 months when lyophilized. Taken together, this saRNA delivered by NLC represents a potential improvement in RNA technology that could allow wider access to RNA vaccines for the current COVID-19 and future pandemics.

immunology↗