Protective antibodies target cryptic epitope unmasked by cleavage of malaria sporozoite protein.

The most advanced monoclonal antibodies (mAbs) and vaccines against malaria target the central repeat region or closely related sequences within the circumsporozoite protein (PfCSP). Here, using an antigen-agnostic strategy to investigate human antibody responses to whole sporozoites, we identified a class of mAbs that target a cryptic PfCSP epitope that is only exposed after cleavage and subsequent pyroglutamylation (pGlu) of the newly formed N terminus. This pGlu-CSP epitope is not targeted by current anti-PfCSP mAbs and is not included in the licensed malaria vaccines.

High-dose intravenous BCG vaccination induces enhanced immune signaling in the airways.

Intradermal Bacillus Calmette-Guérin (BCG) is the most widely administered vaccine, but it does not sufficiently protect adults against pulmonary tuberculosis. Recent studies in nonhuman primates show that intravenous BCG administration offers superior protection against (). We used single-cell analysis of bronchoalveolar lavage cells from rhesus macaques vaccinated via different routes and doses of BCG to identify alterations in the immune ecosystem in the airway following vaccination.

Structural serology of polyclonal antibody responses to mRNA-1273 and NVX-CoV2373 COVID-19 vaccines.

Current COVID-19 vaccines are largely limited in their ability to induce broad, durable immunity against emerging viral variants. Design and development of improved vaccines utilizing existing platforms requires an in-depth understanding of the antigenic and immunogenic properties of available vaccines. Here we examined the antigenicity of two of the original COVID-19 vaccines, mRNA-1273 and NVX-CoV2373, by electron microscopy-based polyclonal epitope mapping (EMPEM) of serum from immunized non-human primates (NHPs) and clinical trial donors.

Humoral correlate of vaccine-mediated protection from tuberculosis identified in humans and non-human primates.

Development of an effective tuberculosis (TB) vaccine has been challenged by incomplete understanding of specific factors that provide protection against (Mtb) and the lack of a known correlate of protection (CoP). Using a combination of samples from a vaccine showing efficacy (DarDar [NCT00052195]) and Bacille Calmette-Guerin (BCG)-immunized humans and nonhuman primates (NHP), we identify a humoral CoP that translates across species and vaccine regimens. Antibodies specific to the DarDar vaccine strain () sonicate (MOS) correlate with protection from the efficacy endpoint of definite TB.

Humoral correlates of protection against following intravenous BCG vaccination in rhesus macaques.

Altering Bacille Calmette-Guérin (BCG) immunization from low-dose intradermal (i.d.) to high-dose intravenous (i.