# The efficacy of Liposomal Encapsulation of Polysaccharides pneumococcal vaccine in protecting aged hosts against invasive Streptococcus pneumoniae infections in murine models

> **NIH NIH R21** · STATE UNIVERSITY OF NEW YORK AT BUFFALO · 2020 · $198,206

## Abstract

PROJECT SUMMARY
 Despite current vaccines, Streptococcus pneumoniae (pneumococcus) remains the leading cause of
community-acquired pneumonia in the elderly. As this vulnerable population is projected to reach two billion
worldwide by 2050, novel preventative approaches that boost resistance to pneumococcal infections are
needed. Background: The Pfeifer group engineered a novel vaccine formulation, termed Liposomal
Encapsulation of Polysaccharides (LEPS) designed to account for both the breadth of bacterial serotypes and
the unique progression profiles that complicate treatment options for pneumococcal disease. This vaccine
candidate has matched and exceeded the capabilities of Prevnar-13 in young mice, prompting the Hypothesis
that vaccination of elderly mice with the LEPS particle will induce robust immune responses relative to current
pneumococcal vaccine formulations. This hypothesis will be addressed through two specific Aims: 1) Test the
effect of LEPS vaccination on immune responses in young versus elderly mice where anti-pneumococcal
antibody levels and function will be assessed; and 2) Test the protective efficacy of LEPS vaccination against
invasive pneumococcal infections in young versus elderly mice in models of primary pneumonia, systemic
infection, and secondary pneumonia following influenza co-infection. Host survival, clinical disease score,
organ-specific bacterial burden, and other indicators of infection severity (organ pathology) will be measured
over time across vaccine and non-vaccine pneumococcal strains to assess serotype-specific protection as well
as cross protection. Significance/Innovation: The LEPS formulation combines both polysaccharides and
protein antigens within the same vaccine, which by itself is innovative and able to provide capsule specific
immunity as well as cross protection against other serotypes and stages of disease progression. From a
manufacturing standpoint, in contrast to current formulations, the LEPS construct is cost effective and easy to
generate. Here, we will test for the first time the effectiveness of the LEPS vaccine within aged animal models.
Potential outcomes include treatment effectiveness beyond current vaccine formulations (i.e., PPSV and PCV),
in which case, we are in an ideal situation for more extensive assessment of the LEPS platform in subsequent
clinical settings. Alternatively, if the current LEPS design does not provide extended protection in the elderly,
with assessment provided through the Bou Ghanem group's expertise, immunological profiling and comparison
will provide the insight needed to refine the LEPS vehicle for subsequent improvements in effectiveness. Under
either scenario, data from the exploratory plans outlined in this R21 application will provide the foundation to
advance the LEPS vehicle (in future collaborative work between the Bou Ghanem and Pfeifer groups) as a
new option for pneumococcal disease in aged populations.

## Key facts

- **NIH application ID:** 9999998
- **Project number:** 5R21AG064215-02
- **Recipient organization:** STATE UNIVERSITY OF NEW YORK AT BUFFALO
- **Principal Investigator:** Elsa Bou Ghanem
- **Activity code:** R21 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $198,206
- **Award type:** 5
- **Project period:** 2019-09-01 → 2022-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9999998

## Citation

> US National Institutes of Health, RePORTER application 9999998, The efficacy of Liposomal Encapsulation of Polysaccharides pneumococcal vaccine in protecting aged hosts against invasive Streptococcus pneumoniae infections in murine models (5R21AG064215-02). Retrieved via AI Analytics 2026-05-21 from https://api.ai-analytics.org/grant/nih/9999998. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*