Bachelors degree in Biomedical Sciences from the Ribeirão Preto Medical School, University of São Paulo (FMRP-USP, 2024). Direct PhD student (since 2025) in the Graduate Program in Cell and Molecular Biology, supported by a FAPESP doctoral fellowship, developing the project Evaluation of the role of the Legionella longbeachae capsule in immunomodulation and in the pathophysiology of lethal infection in murine models. Has experience in hostpathogen interactions, pulmonary infection models, mammalian cell and bacterial culture, animal handling, immunological assays (ELISA), and immunofluorescence.
RESEARCH, TEACHING, or OTHER INTERESTS
Immunology and Microbiology, Biochemistry, Genetics and Molecular Biology
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Scopus Publications
Scopus Publications
The unique Legionella longbeachae capsule favors intracellular replication and immune evasion Silke Schmidt, Sonia Mondino, Laura Gomez-Valero, Pedro Escoll, Danielle P. A. Mascarenhas, Augusto Gonçalves, Pedro H. M. Camara, Francisco J. Garcia Rodriguez, Christophe Rusniok, Martin Sachse, Maryse Moya-Nilges, Thierry Fontaine, Dario S. Zamboni, Carmen Buchrieser Plos Pathogens, 2024 Legionella longbeachae and Legionella pneumophila are the most common causative agents of Legionnaires’ disease. While the clinical manifestations caused by both species are similar, species-specific differences exist in environmental niches, disease epidemiology, and genomic content. One such difference is the presence of a genomic locus predicted to encode a capsule. Here, we show that L. longbeachae indeed expresses a capsule in post-exponential growth phase as evidenced by electron microscopy analyses, and that capsule expression is abrogated when deleting a capsule transporter gene. Capsule purification and its analysis via HLPC revealed the presence of a highly anionic polysaccharide that is absent in the capsule mutant. The capsule is important for replication and virulence in vivo in a mouse model of infection and in the natural host Acanthamoeba castellanii. It has anti-phagocytic function when encountering innate immune cells such as human macrophages and it is involved in the low cytokine responses in mice and in human monocyte derived macrophages, thus dampening the innate immune response. Thus, the here characterized L. longbeachae capsule is a novel virulence factor, unique among the known Legionella species, which may aid L. longbeachae to survive in its specific niches and which partly confers L. longbeachae its unique infection characteristics.
