Jeroen P.J. Saeij

Jeroen Saeij

Position Title
Associate Professor

Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine

VM3A 3325

Research Interests

We study host-parasite interactions between the obligate intracellular eukaryotic parasite Toxoplasma gondii and its hosts.

Apicomplexan parasites are a major cause of mortality and morbidity in humans and livestock. These parasites secrete effector proteins that are involved in acquiring nutrients from the host cell, manipulation of host cell signaling pathways, or blocking the host immune response. These secreted proteins together manipulate the host cell in such a way that it becomes a niche in which these parasites can replicate. In turn, host cells have intricate mechanisms to detect and combat these parasites. As a consequence, these parasites and their hosts co-evolve, leading to variation in both host and parasite genomes and to the emergence of differences in parasite virulence and host resistance. The Saeij lab is interested in how the interactions between parasite and host can lead to disease with a special interest in the genetic basis for individual host differences in resistance and parasite differences in virulence. A major effort of the Saeij lab is to identify genes from a model apicomplexan, Toxoplasma gondii, that mediate the modulation of the host cell and to characterize the proteins encoded by these Toxoplasma genes, their host cell interaction partners, and their role in virulence and co-option of the host cell. We also study host genetic factors involved in resistance to Toxoplasma. Thus, the overarching goal of the lab is to understand Toxoplasma-host interactions. To achieve our goals, we use a combination of genomics, biochemistry, genetics, microscopy, immunology and computational tools.

Grad Group Affiliations

  • Biochemistry, Molecular, Cellular and Developmental Biology
  • Microbiology
  • Immunology
  • Integrative pathobiology

Specialties / Focus

  • Biochemistry
  • Cell Biology
  • Genomics, Proteomics, and Metabolomics
  • Molecular Genetics
  • Molecular Microbiology
  • Signal Transduction
  • Innate Immunity


  • PMI127
  • PMI270
  • PMI202
  • Vet413

Honors and Awards

  • 2010 Pew Scholar in the Biomedical Sciences

    Professional Societies

    • American Society for Microbiology


    • Ph.D Wageningen University, The Netherlands